Why are my Raycaster Sprites blinking and how can I fix it? - javascript

My raycaster's sprites keep blinking, and I think it has to do with ZBuffer.
Using this for reference: https://lodev.org/cgtutor/index.html
I have done plenty of research and can't find any JS raycasters that answer my problem. By sprites, I mean billboarded images, and when you move they blink like an atari game that is being pushed to its limits.
Here is the project on JSFiddle: https://jsfiddle.net/Vakore/bsvx1m26/
Here is where I am using ZBuffer:
for (var stripe = drawStartX; stripe < drawEndX; stripe++) {
var texX =
floor((256 * (stripe - (-spriteWidth / 2 + spriteScreenX)) * texWidth) / spriteWidth) / 256;
// the conditions in the if are:
// 1) it's in front of camera plane so you don't see things behind you
// 2) it's on the screen (left)
// 3) it's on the screen (right)
// 4) ZBuffer, with perpendicular distance
var ruffer = 0;
if (sprite[i][2] == "barrel") {
ruffer = 576 - 64;
}
if (sprite[i][2] == "pillar") {
ruffer = 576;
}
if (sprite[i][2] == "greenlight") {
ruffer = 576 + 64;
}
if (
transformY > 0 &&
stripe > 0 &&
stripe < w &&
transformY < ZBuffer[stripe]
) {
can.drawImage(
document.getElementById(sprite[i][2]),
texX + ruffer, 0, 1, texHeight, stripe, drawStartY, 1, drawEndY - drawStartY
);
}
}
ZBuffer was declared and assigned an array value earlier in the code.
var keys = {
"a": false,
"s": false,
"d": false,
"A": false,
"S": false,
"D": false,
"W": false,
"Z": false,
"X": false,
"C": false,
"ENTER": false
};
document.addEventListener("keydown", function(e) {
e.preventDefault();
if (e.keyCode === 16)
keys["SHIFT"] = true;
if (e.keyCode === 37)
keys["a"] = true;
if (e.keyCode === 39)
keys["d"] = true;
if (e.keyCode === 65)
keys["A"] = true;
if (e.keyCode === 68)
keys["D"] = true;
if (e.keyCode === 83)
keys["S"] = true;
if (e.keyCode === 87)
keys["W"] = true;
if (e.keyCode === 40)
keys["S"] = true;
if (e.keyCode === 38)
keys["W"] = true;
if (e.keyCode === 67)
keys["C"] = true;
if (e.keyCode === 88)
keys["X"] = true;
if (e.keyCode === 90)
keys["Z"] = true;
if (e.keyCode === 13)
keys["ENTER"] = true;
})
document.addEventListener("keyup", function(e) {
e.preventDefault();
if (e.keyCode === 16)
keys["SHIFT"] = false;
if (e.keyCode === 37)
keys["a"] = false;
if (e.keyCode === 39)
keys["d"] = false;
if (e.keyCode === 65)
keys["A"] = false;
if (e.keyCode === 68)
keys["D"] = false;
if (e.keyCode === 83)
keys["S"] = false;
if (e.keyCode === 87)
keys["W"] = false;
if (e.keyCode === 40)
keys["S"] = false;
if (e.keyCode === 38)
keys["W"] = false;
if (e.keyCode === 67)
keys["C"] = false;
if (e.keyCode === 88)
keys["X"] = false;
if (e.keyCode === 90)
keys["Z"] = false;
})
/*
Basic functions(ease of access)
*/
var canvas = document.getElementById("canva");
var can = canvas.getContext("2d");
canvas.requestPointerLock = canvas.requestPointerLock || canvas.mozRequestPointerLock;
document.exitPointerLock = document.exitPointerLock || document.mozExitPointerLock;
canvas.onclick = function() {
canvas.requestPointerLock();
clicked = true;
};
var mouseX = 0;
var mouseMove = function(e) {
mouseX += e.movementX;
};
var rect = function(x, y, w, h) {
can.fillRect(x, y, w, h);
};
var arc = function(x, y, r, start, stop) {
can.beginPath();
can.arc(x, y, r, start, stop);
can.fill();
};
var circle = function(x, y, r) {
arc(x, y, r, 0, 360);
};
var fill = function(r, g, b, a) {
if (a === undefined) {
a = 1;
}
can.fillStyle = "rgb(" + r + "," + g + "," + b + "," + a + ")";
};
var font = function(siz) {
can.font = siz;
};
var textAlign = function(ali) {
can.textAlign = ali;
};
var text = function(txt, x, y, w, h) {
can.fillText(txt, x, y, w, h);
};
var quad = function(x1, y1, x2, y2, x3, y3, x4, y4) {
can.beginPath();
can.moveTo(x1, y1);
can.lineTo(x2, y2);
can.lineTo(x3, y3);
can.lineTo(x4, y4);
can.closePath();
can.fill();
};
var random = function(min, max) {
return round(Math.random() * (max - min)) + min;
};
var translate = function(x, y) {
can.save();
can.translate(x, y);
};
var scale = function(w, h) {
can.scale(w, h);
}
var trestore = function() {
can.restore();
};
var floor = function(num) {
return Math.floor(num);
};
var sqrt = function(num) {
return Math.sqrt(num);
};
var abs = function(num) {
return Math.abs(num);
};
var color = function(r, g, b, a) {
return [r, g, b, a];
};
var dist = function() {
return true;
};
var cos = function(num) {
return Math.cos(num);
}
var sin = function(num) {
return Math.sin(num);
}
var dist = function(x1, y1, x2, y2) {
dx = x1 - x2;
dy = y1 - y2;
return Math.sqrt(dx * dx + dy * dy);
};
//Begin the raycaster
var scaler = 3; //This reduces the resolution so that it can display large rooms without lagging
var w = 640 / scaler;
var h = 480 / scaler;
var texWidth = 64;
var texHeight = 64;
var rotSpeed = 0.1;
var moveSpeed = 0.1;
var worldMap = [
"1111111111111111111111111111111111111111",
"1001000001234567800000000000000000000001",
"1001000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1001000000000000000000000000000000000001",
"1001000000000000000000000000222200000001",
"1001000000000000000000000000200200000001",
"1111000000000000000000000000200200000001",
"1000000000000000000000000033300333000001",
"8008000000000000000000000000000000000001",
"8000800000000000000000000033300333000001",
"8000080000000000000000000000300300000001",
"8000008000000000000000000000333300000001",
"8888888000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1666006660000000000000000000000000000001",
"1000000060000000000000000000000000000001",
"1000000060000000000000000000000000000001",
"1000000060000000000000000000000000000001",
"1000000060000000000000000000000000000001",
"1666666660000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000000000000000000000000000001",
"1000000040444444444444400000000000000001",
"1000000040000000000000400000000000000001",
"1000000040000000000000400000000000000001",
"1000000040000000000000400000000000000001",
"1000000044444444444444400000000000000001",
"1000000000000000000000000000000000000001",
"1000000000000007775777000000000000000001",
"1000000000000007000007000000000000000001",
"1000000000000005000005000000000000000001",
"1000000000000007000007000000000000000001",
"1000000000000000000007000000000000000001",
"1111111111111117775777111111111111111111",
];
try {
var ZBuffer = [];
var sprite = [
[5, 5, "barrel", 0], //Y and X are reversed
[6.5, 2.5, "pillar", 1],
[6.5, 1.5, "pillar", 1.5],
[8, 6, "greenlight", 2],
];
var posX = 2,
posY = 2,
dirX = -1,
dirY = 0,
planeX = 0,
planeY = 0.66; //The 2d raycaster version of the camera plane
} catch (e) {
alert(e);
}
var castRays = function() {
for (var x = 0; x < w; x++) {
var cameraX = 2 * x / (w) - 1; //x-coordinate in camera space
var rayDirX = dirX + planeX * cameraX;
var rayDirY = dirY + planeY * cameraX;
//which box of the map we're in
var mapX = floor(posX);
var mapY = floor(posY);
//length of ray from current position to next x or y-side
var sideDistX;
var sideDistY;
//length of ray from one x or y-side to next x or y-side
var deltaDistX = sqrt(1 + (rayDirY * rayDirY) / (rayDirX * rayDirX));
var deltaDistY = sqrt(1 + (rayDirX * rayDirX) / (rayDirY * rayDirY));
var perpWallDist = 0;
//what direction to step in x or y-direction (either +1 or -1)
var stepX = 0;
var stepY = 0;
var hit = 0; //was there a wall hit?
var side = 0; //was a NS or a EW wall hit?
//calculate step and initial sideDist
if (rayDirX < 0) {
stepX = -1;
sideDistX = (posX - mapX) * deltaDistX;
} else {
stepX = 1;
sideDistX = (mapX + 1.0 - posX) * deltaDistX;
}
if (rayDirY < 0) {
stepY = -1;
sideDistY = (posY - mapY) * deltaDistY;
} else {
stepY = 1;
sideDistY = (mapY + 1.0 - posY) * deltaDistY;
}
while (hit == 0) {
//jump to next map square, OR in x-direction, OR in y-direction
if (sideDistX < sideDistY) {
sideDistX += deltaDistX;
mapX += stepX;
side = 0;
} else {
sideDistY += deltaDistY;
mapY += stepY;
side = 1;
}
//Check if ray has hit a wall
if (worldMap[mapX][mapY] == 0) {}
if (worldMap[mapX][mapY] != 0) {
hit = 1;
}
} //end of while loop
//Calculate distance of perpendicular ray (Euclidean distance will give fisheye effect!)
if (side == 0) {
perpWallDist = (mapX - posX + (1 - stepX) / 2) / rayDirX;
} else {
perpWallDist = (mapY - posY + (1 - stepY) / 2) / rayDirY;
}
//Calculate height of line to draw on screen
var lineHeight = abs(floor(h / perpWallDist));
//calculate lowest and highest pixel to fill in current stripe
var drawStart = -lineHeight / 2 + h / 2;
//if(drawStart < 0) {drawStart = 0;}
var drawEnd = lineHeight / 2 + h / 2;
//if(drawEnd >= h) {drawEnd = h - 1;}
//texturing calculations
//var texNum = worldMap[mapX][mapY] - 1; //1 subtracted from it so that texture 0 can be used!
//calculate value of wallX
var wallX = 0; //where exactly the wall was hit
if (side == 0) {
wallX = posY + perpWallDist * rayDirY;
} else {
wallX = posX + perpWallDist * rayDirX;
}
wallX -= floor((wallX));
//x coordinate on the texture
var texX = floor(wallX * (texWidth));
if (side == 0 && rayDirX > 0) {
texX = texWidth - texX - 1;
}
if (side == 1 && rayDirY < 0) {
texX = texWidth - texX - 1;
}
//Untextured variant
/*var currentColor = color(255, 255, 255);
if (worldMap[mapX][mapY] == "1") {currentColor = color(150, 150, 150);}
if (worldMap[mapX][mapY] == "2") {currentColor = color(255, 255, 255);}
if (worldMap[mapX][mapY] == "3") {currentColor = color(255,0,0);}
if (worldMap[mapX][mapY] == "4") {currentColor = color(0,0,255);}
if (worldMap[mapX][mapY] == "5") {currentColor = color(0,255,0);}
if (worldMap[mapX][mapY] == "6") {currentColor = color(255,0,255);}
if (worldMap[mapX][mapY]=="7") {currentColor = color(0,255,255);}
if (side === 1) {currentColor = [currentColor[0] - 40, currentColor[1] - 40, currentColor[2] - 40];}
//if (dist(mapX, mapY, px, pz) > 10) {continue;}
fill(currentColor[0],currentColor[1],currentColor[2]);
rect(x, drawStart, 1, drawEnd - drawStart);*/
var currentImg = "bluestone";
if (worldMap[mapX][mapY] == "1") {
currentImg = "bluestone";
}
if (worldMap[mapX][mapY] == "2") {
currentImg = "greystone";
}
if (worldMap[mapX][mapY] == "3") {
currentImg = "wood";
}
if (worldMap[mapX][mapY] == "4") {
currentImg = "colorstone";
}
if (worldMap[mapX][mapY] == "5") {
currentImg = "eagle";
}
if (worldMap[mapX][mapY] == "6") {
currentImg = "mossy";
}
if (worldMap[mapX][mapY] == "7") {
currentImg = "redbrick";
}
if (worldMap[mapX][mapY] == "8") {
currentImg = "purplestone";
}
//if (worldMap[mapX][mapY] =="a") {currentImg = "barrel";}
//if (dist(mapX, mapY, posX, posY) > 20) {continue;}
can.drawImage(document.getElementById(currentImg), texX + ((worldMap[mapX][mapY] - 1) * 64), 0, 1, texHeight, x, drawStart, 1, drawEnd - drawStart);
//fill(255, 0, 0);rect(x, drawStart, 1, drawEnd - drawStart);
if (side === 1) {
fill(0, 0, 0, 0.3);
rect(x, drawStart, 1, drawEnd - drawStart);
}
//Set the ZBuffer
ZBuffer[x] = perpWallDist;
//FLOOR CASTING(not using till figure out how to do without lag)
var floorXWall = 0,
floorYWall = 0;
if (side == 0 && rayDirX > 0) {
floorXWall = mapX;
floorYWall = mapY + wallX;
} else if (side == 0 && rayDirX < 0) {
floorXWall = mapX + 1.0;
floorYWall = mapY + wallX;
} else if (side == 1 && rayDirY > 0) {
floorXWall = mapX + wallX;
floorYWall = mapY;
} else {
floorXWall = mapX + wallX;
floorYWall = mapY + 1.0;
}
var distWall, distPlayer, currentDist;
distWall = perpWallDist;
distPlayer = 0.0;
for (var y = drawEnd + 1; y < h; y++) {
//if (dist(mapX, mapY, posX, posY) > 5) {continue;}
currentDist = h / (2.0 * y - h); //you could make a small lookup table for this instead
var weight = (currentDist - distPlayer) / (distWall - distPlayer);
var currentFloorX = weight * floorXWall + (1.0 - weight) * posX;
var currentFloorY = weight * floorYWall + (1.0 - weight) * posY;
var floorTexX, floorTexY;
floorTexX = floor(currentFloorX * texWidth) % texWidth;
floorTexY = floor(currentFloorY * texHeight) % texHeight;
//OPTIMIZE FOR LESS LAG!!!!!!!!!! (search
//FLOOR
//can.drawImage(document.getElementById("greystone"), floorTexX, floorTexY, texWidth, texHeight, x, y, texWidth, texHeight);
//CEILING
//can.drawImage(document.getElementById("wood"), floorTexX, floorTexY, texWidth, 1, x, h - y, texWidth, 1);
} //End of the 'y' loop
} //end the loop
//SPRITE CASTING
//Sort sprites
sprite.sort(function(a, b) {
return b[3] - a[3];
}); //Sort the depth of each sprite
//Draw sprites
for (var i = 0; i < sprite.length; i++) {
var spriteX = sprite[i][0] - posX;
var spriteY = sprite[i][1] - posY;
sprite[i][3] = abs((posX - sprite[i][0]) - (posY - sprite[i][1]));
var invDet = 1.0 / (planeX * dirY - dirX * planeY);
var transformX = invDet * (dirY * spriteX - dirX * spriteY);
var transformY = invDet * (-planeY * spriteX + planeX * spriteY); //this is actually the depth inside the screen, that what Z is in 3D(Thanks lodev.org for explanation!)
var spriteScreenX = floor((w / 2) * (1 + transformX / transformY));
//calculate height of the sprite on screen
var spriteHeight = abs(floor(h / (transformY))); //using "transformY" instead of the real distance prevents fisheye
//calculate lowest and highest pixel to fill in current stripe
var drawStartY = -spriteHeight / 2 + h / 2;
//if (drawStartY < 0) {drawStartY = 0;} Don't need THIS
var drawEndY = spriteHeight / 2 + h / 2;
//if (drawEndY >= h) {drawEndY = h - 1;} Or THIS
//calculate width of the sprite
var spriteWidth = abs(floor(h / (transformY)));
var drawStartX = -spriteWidth / 2 + spriteScreenX;
//if (drawStartX < 0) {drawStartX = 0;} Nor this
var drawEndX = spriteWidth / 2 + spriteScreenX;
//if (drawEndX >= w) {drawEndX = w - 1;} Nor dis
//loop through every vertical stripe of the sprite on screen
for (var stripe = drawStartX; stripe < drawEndX; stripe++) {
var texX = floor(256 * (stripe - (-spriteWidth / 2 + spriteScreenX)) * texWidth / spriteWidth) / 256;
//the conditions in the if are:
//1) it's in front of camera plane so you don't see things behind you
//2) it's on the screen (left)
//3) it's on the screen (right)
//4) ZBuffer, with perpendicular distance
var ruffer = 0;
if (sprite[i][2] == "barrel") {
ruffer = 576 - 64;
}
if (sprite[i][2] == "pillar") {
ruffer = 576;
}
if (sprite[i][2] == "greenlight") {
ruffer = 576 + 64;
}
if (transformY > 0 && stripe > 0 && stripe < w && transformY < ZBuffer[stripe]) {
can.drawImage(document.getElementById(sprite[i][2]), texX + ruffer, 0, 1, texHeight, stripe, drawStartY, 1, drawEndY - drawStartY);
}
}
} //End of 'i' loop
//Bottom of dat
if (keys["W"]) {
if (worldMap[floor(posX + dirX * moveSpeed)][floor(posY)] == false) {
posX += dirX * moveSpeed
};
if (worldMap[floor(posX)][floor(posY + dirY * moveSpeed)] == false) {
posY += dirY * moveSpeed
};
}
//move backwards if no wall behind you
if (keys["S"]) {
if (worldMap[floor(posX - dirX * moveSpeed)][floor(posY)] == false) {
posX -= dirX * moveSpeed;
}
if (worldMap[floor(posX)][floor(posY - dirY * moveSpeed)] == false) {
posY -= dirY * moveSpeed;
}
}
if (keys["D"]) {
if (worldMap[floor(posX + planeX * moveSpeed)][floor(posY)] == false) {
posX += planeX * moveSpeed
};
if (worldMap[floor(posX)][floor(posY + planeY * moveSpeed)] == false) {
posY += planeY * moveSpeed
};
}
if (keys["A"]) {
if (worldMap[floor(posX - planeX * moveSpeed)][floor(posY)] == false) {
posX -= planeX * moveSpeed;
}
if (worldMap[floor(posX)][floor(posY - planeY * moveSpeed)] == false) {
posY -= planeY * moveSpeed;
}
}
//rotate to the right
mouseX = -mouseX / 75;
var oldDirX = dirX;
dirX = dirX * cos(mouseX) - dirY * sin(mouseX);
dirY = oldDirX * sin(mouseX) + dirY * cos(mouseX);
var oldPlaneX = planeX;
planeX = planeX * cos(mouseX) - planeY * sin(mouseX);
planeY = oldPlaneX * sin(mouseX) + planeY * cos(mouseX);
mouseX = 0;
if (keys["d"]) {
//both camera direction and camera plane must be rotated
var oldDirX = dirX;
dirX = dirX * cos(-rotSpeed) - dirY * sin(-rotSpeed);
dirY = oldDirX * sin(-rotSpeed) + dirY * cos(-rotSpeed);
var oldPlaneX = planeX;
planeX = planeX * cos(-rotSpeed) - planeY * sin(-rotSpeed);
planeY = oldPlaneX * sin(-rotSpeed) + planeY * cos(-rotSpeed);
}
//rotate to the left
if (keys["a"]) {
//both camera direction and camera plane must be rotated
var oldDirX = dirX;
dirX = dirX * cos(rotSpeed) - dirY * sin(rotSpeed);
dirY = oldDirX * sin(rotSpeed) + dirY * cos(rotSpeed);
var oldPlaneX = planeX;
planeX = planeX * cos(rotSpeed) - planeY * sin(rotSpeed);
planeY = oldPlaneX * sin(rotSpeed) + planeY * cos(rotSpeed);
}
};
var run = function() {
try {
if (document.pointerLockElement === canvas || document.mozPointerLockElement === canvas) {
document.addEventListener("mousemove", mouseMove, false);
} else {
document.removeEventListener("mousemove", mouseMove, false);
} //Mouse stuff
translate(0, 0);
scale(scaler, scaler);
fill(40, 40, 40);
rect(0, 0, w, h / 2);
fill(80, 80, 80);
rect(0, h / 2, w, h / 2);
if (keys["C"]) {
rotSpeed = 0.04;
} else {
rotSpeed = 0.1;
}
/*if (keys["W"]) {fill(255, 0, 0);}
if (keys["A"]) {fill(0, 255, 0);}
if (keys["S"]) {fill(0, 0, 255);}
if (keys["D"]) {fill(255, 0, 255);}
if (keys["X"]) {fill(255, 255, 0);}
if (keys["Z"]) {fill(0, 255, 255);}*/
castRays();
trestore();
requestAnimationFrame(run);
} catch (e) {
alert(e);
}
};
run();
<html>
<title>Jailbreak</title>
<div class="center">
<canvas width="640" height="480" id="canva"></canvas>
<br>
<img id="barrel" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="pillar" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="greenlight" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="bluestone" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="greystone" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="wood" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="colorstone" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="eagle" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="mossy" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="redbrick" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
<img id="purplestone" src="https://lodev.org/cgtutor/images/wolftexturesobj.gif">
</div>
</html>
UPDATE: I tried changing
if (
transformY > 0 &&
stripe > 0 &&
stripe < w &&
transformY < ZBuffer[stripe]//Pay attention to this line
) {
to:
if (
transformY > 0 &&
stripe > 0 &&
stripe < w &&
transformY > ZBuffer[stripe]//Now look
) {
Which basically reverses the check to see if it is behind a wall. Surprisingly, the blinking continues.

The answer was pretty simple. It was because stripe is not an even value, and if you were to have an array like this: var thisArray = [1, 2, 3, 4]; and you were to try and grab var money = thisArray[1.5]; the value undefined would be returned.
So I changed this:
if (
transformY > 0 &&
stripe > 0 &&
stripe < w &&
transformY < ZBuffer[stripe]
) {
To this:
if (
transformY > 0 &&
stripe > 0 &&
stripe < w &&
transformY < ZBuffer[Math.round(stripe)]
) {
Math.floor also works, since it also returns an integer value.

Related

how to fix bugs in snake game?

I have been making a snake game for a few days to improve my js skills.
And I released the first beta test of my mini-game. And you actually know that there are always a lot of bugs in beta tests. And I noticed them. First I notice that if the snake.x position < 0, then the snake appears from a different corner, but in front of one block, and not from the zero coordinate. This also applies to snake.y<0.
here is the code:
var canvas = document.getElementById("game");
var ctx = canvas.getContext("2d");
var box = 10;
//Snake
var snake = [];
var dir = "right";
var maxCell = 10;
var can = canvas.getBoundingClientRect();
var px = Math.floor(canvas.width / 2 / 10) * 10;
var py = Math.floor(canvas.height / 2 / 10) * 10;
//Apple
var ax = Math.floor((Math.random() * ~~(canvas.width / box)) / 10) * 10;
var ay = Math.floor((Math.random() * ~~(canvas.height / box)) / 10) * 10;
var loop = setInterval(() => {
ctx.clearRect(0, 0, canvas.width, canvas.height);
Elems();
}, 1000 / 40);
document.addEventListener("keydown", function (e) {
if (e.keyCode === 37 && dir !== "right") {
dir = "left";
//console.log('left')
} else if (e.keyCode === 38 && dir !== "down") {
dir = "up";
//console.log('up')
} else if (e.keyCode === 39 && dir !== "left") {
dir = "right";
//console.log('right')
} else if (e.keyCode === 40 && dir !== "up") {
dir = "down";
//console.log('down')
}
});
function direction() {
if (dir == "right") {
px += box;
} else if (dir == "left") {
px -= box;
} else if (dir == "up") {
py -= box;
} else if (dir == "down") {
py += box;
}
}
//Closure )))
function Elems() {
function Apple() {
ctx.fillStyle = "green";
ctx.fillRect(ax, ay, box, box);
}
//! Spawn snake
function Snake() {
direction();
var head = {
x: px,
y: py,
};
snake.unshift(head);
//-------------BUG---------------
if (px >= canvas.width) {
px = 0;
}
if (px + box < 0) {
px = canvas.width;
}
if (py >= canvas.height) {
py = 0;
}
if (py + box < 0) {
py = canvas.height;
}
//-------------------------------
snake.forEach(function (elem, index) {
ctx.fillStyle = `red`;
ctx.fillRect(elem.x, elem.y, box, box);
});
if (head.x == ax && head.y == ay) {
maxCell += 1;
ax = Math.floor(Math.random() * ~~(canvas.width / box)) * 10;
ay = Math.floor(Math.random() * ~~(canvas.height / box)) * 10;
}
for (let i = 1; i < snake.length; i++) {
if (head.x === snake[i].x && head.y === snake[i].y) {
maxCell = 10;
px = Math.floor(canvas.width / 2 / 10) * 10;
py = Math.floor(canvas.height / 2 / 10) * 10;
clearInterval(loop);
alert("Game Over:(")
}
}
if (snake.length < maxCell) {
snake.push({ x: px, y: py });
}
snake.pop();
}
Snake();
Apple();
}
I tried changing the canvas dimensions and box value. But it didn't help x((((
You'd have to rearrange your code a good bit to get it working right.
The Snake function should not happen in a loop, the loop related stuff inside of Snake should be inside the Elems function instead. And the loop being set should happen last.
The following is a basic rework of your code with an added method, and I've included the grid that angel.bonev suggested so it works like a traditional snake game now and with the apple getting eaten to increase the snake size. The testForPointInArea method makes it such that the snake does not have to be exactly over the apple spot, but just overlapping.
Also the opposite direction restrictions in the keydown listener were removed;
&& dir !== "right" && dir !== "down" && dir !== "left" && dir !== "up"
If the snake is a small size or not big enough to bank corners,
then game over would not happen with the above backwards restrictions.
var canvas = document.getElementById("game");
var ctx = canvas.getContext("2d");
var box = 10;
//Snake body Array
var snake = [];
var dir = "right";
var maxCell = 2;
var can = canvas.getBoundingClientRect();
var grid = {
x: Math.floor(canvas.width / box),
y: Math.floor(canvas.height / box)
};
var px = Math.floor(grid.x / 2) * 10;
var py = Math.floor(grid.y / 2) * 10;
//Apple cords
var ax = Math.floor( Math.random() * grid.y ) * box;
var ay = Math.floor( Math.random() * grid.x ) * box;
var theSnake;
document.addEventListener("keydown", function(e) {
e.preventDefault();
if (e.keyCode === 37 ) {
dir = "left";
//console.log('left')
} else if (e.keyCode === 38 ) {
dir = "up";
//console.log('up')
} else if (e.keyCode === 39) {
dir = "right";
//console.log('right')
} else if (e.keyCode === 40 ) {
dir = "down";
//console.log('down')
}
});
function direction() {
if (dir == "right") {
px += 2;
} else if (dir == "left") {
px -= 2;
} else if (dir == "up") {
py -= 2;
} else if (dir == "down") {
py += 2;
}
}
function Apple() {
ctx.fillStyle = "green";
ctx.fillRect(ax, ay, box, box);
}
function testForPointInArea(p, left,top,right,bottom) {
return Boolean(!(p.x < left || p.x > right || p.y < top || p.y > bottom));
}
function Elems() {
direction();
theSnake.head.x = px; theSnake.head.y = py;
snake.unshift({x:theSnake.head.x, y:theSnake.head.y});
for (let i = 1; i < snake.length; i++) {
if (theSnake.head.x === snake[i].x && theSnake.head.y === snake[i].y) {
maxCell = 2;
px = Math.floor(grid.x / 2) * 10;
py = Math.floor(grid.y / 2) * 10;
snake = [];
//clearInterval(loop);
alert("Game Over :(");
return;
}
}
if (snake.length < maxCell) {
snake.push({ x: px, y: py });
}
if (px >= canvas.width) {
px = 0;
}
if (px + box < 0) {
px = canvas.width;
}
if (py >= canvas.height) {
py = 0;
}
if (py + box < 0) {
py = canvas.height;
}
theSnake.drawSnake();
Apple();
snake.pop();
if ( testForPointInArea(theSnake.head, ax - 3, ay - 3, ax + box + 3, ay + box + 3) ) {
maxCell += 1;
ax = Math.floor( Math.random() * grid.y ) * box;
ay = Math.floor( Math.random() * grid.x ) * box;
Apple();
}
}
//Snake Class
function Snake() {
this.head = {
x: px,
y: py,
};
this.drawSnake = function() {
snake.forEach(function (elem, index) {
ctx.fillStyle = "red";
ctx.fillRect(elem.x, elem.y, box, box);
});
};
}
theSnake = new Snake();
var loop = setInterval(() => {
ctx.clearRect(0, 0, canvas.width, canvas.height);
Elems();
}, 1000 / 40);
<canvas id="game" width="150px" height="150px"> </canvas>

Trying to add this to my website on sqaurespace

I've been trying to add a (code pen) animation on my website and I'm honestly not sure what I'm missing on this one. I have tried running it in jsfiddle as well and it tells me that delaunay is not defined. https://codepen.io/hduffin1/pen/QOMZJg I'm not too sure what I'm doing wrong since the code works inside of code pen and I have been able to replicate other ones that I've tried using from code pen but for whatever reason, I can't seem to get this one to work.
Html
<canvas id="stars" width="300" height="300"></canvas>
CSS
html,
body {
margin: 0;
padding: 0;
}
body {
background-color: #31102f; //#280B29
background: radial-gradient(
ellipse at center,
rgba(49, 16, 47, 1) 0%,
rgba(40, 11, 41, 1) 100%
);
}
#stars {
display: block;
position: relative;
width: 100%;
height: 16rem;
height: 100vh;
z-index: 1;
}
JS
/**
* Stars
* Inspired by Steve Courtney's poster art for Celsius GS's Drifter - http://celsiusgs.com/drifter/posters.php
* by Cory Hughart - http://coryhughart.com
*/
// Settings
var particleCount = 40,
flareCount = 10,
motion = 0.05,
tilt = 0.05,
color = '#FFEED4',
particleSizeBase = 1,
particleSizeMultiplier = 0.5,
flareSizeBase = 100,
flareSizeMultiplier = 100,
lineWidth = 1,
linkChance = 75, // chance per frame of link, higher = smaller chance
linkLengthMin = 5, // min linked vertices
linkLengthMax = 7, // max linked vertices
linkOpacity = 0.25; // number between 0 & 1
linkFade = 90, // link fade-out frames
linkSpeed = 1, // distance a link travels in 1 frame
glareAngle = -60,
glareOpacityMultiplier = 0.05,
renderParticles = true,
renderParticleGlare = true,
renderFlares = true,
renderLinks = true,
renderMesh = false,
flicker = true,
flickerSmoothing = 15, // higher = smoother flicker
blurSize = 0,
orbitTilt = true,
randomMotion = true,
noiseLength = 1000,
noiseStrength = 1;
var canvas = document.getElementById('stars'),
//orbits = document.getElementById('orbits'),
context = canvas.getContext('2d'),
mouse = { x: 0, y: 0 },
m = {},
r = 0,
c = 1000, // multiplier for delaunay points, since floats too small can mess up the algorithm
n = 0,
nAngle = (Math.PI * 2) / noiseLength,
nRad = 100,
nScale = 0.5,
nPos = {x: 0, y: 0},
points = [],
vertices = [],
triangles = [],
links = [],
particles = [],
flares = [];
function init() {
var i, j, k;
// requestAnimFrame polyfill
window.requestAnimFrame = (function(){
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
function( callback ){
window.setTimeout(callback, 1000 / 60);
};
})();
// Fade in background
/*
var background = document.getElementById('background'),
bgImg = new Image(),
bgURL = '/img/background.jpg';
bgImg.onload = function() {
//console.log('background loaded');
background.style.backgroundImage = 'url("'+bgURL+'")';
background.className += ' loaded';
}
bgImg.src = bgURL;
*/
// Size canvas
resize();
mouse.x = canvas.clientWidth / 2;
mouse.y = canvas.clientHeight / 2;
// Create particle positions
for (i = 0; i < particleCount; i++) {
var p = new Particle();
particles.push(p);
points.push([p.x*c, p.y*c]);
}
//console.log(JSON.stringify(points));
// Delaunay triangulation
//var Delaunay = require('delaunay-fast');
vertices = Delaunay.triangulate(points);
//console.log(JSON.stringify(vertices));
// Create an array of "triangles" (groups of 3 indices)
var tri = [];
for (i = 0; i < vertices.length; i++) {
if (tri.length == 3) {
triangles.push(tri);
tri = [];
}
tri.push(vertices[i]);
}
//console.log(JSON.stringify(triangles));
// Tell all the particles who their neighbors are
for (i = 0; i < particles.length; i++) {
// Loop through all tirangles
for (j = 0; j < triangles.length; j++) {
// Check if this particle's index is in this triangle
k = triangles[j].indexOf(i);
// If it is, add its neighbors to the particles contacts list
if (k !== -1) {
triangles[j].forEach(function(value, index, array) {
if (value !== i && particles[i].neighbors.indexOf(value) == -1) {
particles[i].neighbors.push(value);
}
});
}
}
}
//console.log(JSON.stringify(particles));
if (renderFlares) {
// Create flare positions
for (i = 0; i < flareCount; i++) {
flares.push(new Flare());
}
}
// Motion mode
//if (Modernizr && Modernizr.deviceorientation) {
if ('ontouchstart' in document.documentElement && window.DeviceOrientationEvent) {
console.log('Using device orientation');
window.addEventListener('deviceorientation', function(e) {
mouse.x = (canvas.clientWidth / 2) - ((e.gamma / 90) * (canvas.clientWidth / 2) * 2);
mouse.y = (canvas.clientHeight / 2) - ((e.beta / 90) * (canvas.clientHeight / 2) * 2);
//console.log('Center: x:'+(canvas.clientWidth/2)+' y:'+(canvas.clientHeight/2));
//console.log('Orientation: x:'+mouse.x+' ('+e.gamma+') y:'+mouse.y+' ('+e.beta+')');
}, true);
}
else {
// Mouse move listener
console.log('Using mouse movement');
document.body.addEventListener('mousemove', function(e) {
//console.log('moved');
mouse.x = e.clientX;
mouse.y = e.clientY;
});
}
// Random motion
if (randomMotion) {
//var SimplexNoise = require('simplex-noise');
//var simplex = new SimplexNoise();
}
// Animation loop
(function animloop(){
requestAnimFrame(animloop);
resize();
render();
})();
}
function render() {
if (randomMotion) {
n++;
if (n >= noiseLength) {
n = 0;
}
nPos = noisePoint(n);
//console.log('NOISE x:'+nPos.x+' y:'+nPos.y);
}
// Clear
context.clearRect(0, 0, canvas.width, canvas.height);
if (blurSize > 0) {
context.shadowBlur = blurSize;
context.shadowColor = color;
}
if (renderParticles) {
// Render particles
for (var i = 0; i < particleCount; i++) {
particles[i].render();
}
}
if (renderMesh) {
// Render all lines
context.beginPath();
for (var v = 0; v < vertices.length-1; v++) {
// Splits the array into triplets
if ((v + 1) % 3 === 0) { continue; }
var p1 = particles[vertices[v]],
p2 = particles[vertices[v+1]];
//console.log('Line: '+p1.x+','+p1.y+'->'+p2.x+','+p2.y);
var pos1 = position(p1.x, p1.y, p1.z),
pos2 = position(p2.x, p2.y, p2.z);
context.moveTo(pos1.x, pos1.y);
context.lineTo(pos2.x, pos2.y);
}
context.strokeStyle = color;
context.lineWidth = lineWidth;
context.stroke();
context.closePath();
}
if (renderLinks) {
// Possibly start a new link
if (random(0, linkChance) == linkChance) {
var length = random(linkLengthMin, linkLengthMax);
var start = random(0, particles.length-1);
startLink(start, length);
}
// Render existing links
// Iterate in reverse so that removing items doesn't affect the loop
for (var l = links.length-1; l >= 0; l--) {
if (links[l] && !links[l].finished) {
links[l].render();
}
else {
delete links[l];
}
}
}
if (renderFlares) {
// Render flares
for (var j = 0; j < flareCount; j++) {
flares[j].render();
}
}
/*
if (orbitTilt) {
var tiltX = -(((canvas.clientWidth / 2) - mouse.x + ((nPos.x - 0.5) * noiseStrength)) * tilt),
tiltY = (((canvas.clientHeight / 2) - mouse.y + ((nPos.y - 0.5) * noiseStrength)) * tilt);
orbits.style.transform = 'rotateY('+tiltX+'deg) rotateX('+tiltY+'deg)';
}
*/
}
function resize() {
canvas.width = window.innerWidth * (window.devicePixelRatio || 1);
canvas.height = canvas.width * (canvas.clientHeight / canvas.clientWidth);
}
function startLink(vertex, length) {
//console.log('LINK from '+vertex+' (length '+length+')');
links.push(new Link(vertex, length));
}
// Particle class
var Particle = function() {
this.x = random(-0.1, 1.1, true);
this.y = random(-0.1, 1.1, true);
this.z = random(0,4);
this.color = color;
this.opacity = random(0.1,1,true);
this.flicker = 0;
this.neighbors = []; // placeholder for neighbors
};
Particle.prototype.render = function() {
var pos = position(this.x, this.y, this.z),
r = ((this.z * particleSizeMultiplier) + particleSizeBase) * (sizeRatio() / 1000),
o = this.opacity;
if (flicker) {
var newVal = random(-0.5, 0.5, true);
this.flicker += (newVal - this.flicker) / flickerSmoothing;
if (this.flicker > 0.5) this.flicker = 0.5;
if (this.flicker < -0.5) this.flicker = -0.5;
o += this.flicker;
if (o > 1) o = 1;
if (o < 0) o = 0;
}
context.fillStyle = this.color;
context.globalAlpha = o;
context.beginPath();
context.arc(pos.x, pos.y, r, 0, 2 * Math.PI, false);
context.fill();
context.closePath();
if (renderParticleGlare) {
context.globalAlpha = o * glareOpacityMultiplier;
/*
context.ellipse(pos.x, pos.y, r * 30, r, 90 * (Math.PI / 180), 0, 2 * Math.PI, false);
context.fill();
context.closePath();
*/
context.ellipse(pos.x, pos.y, r * 100, r, (glareAngle - ((nPos.x - 0.5) * noiseStrength * motion)) * (Math.PI / 180), 0, 2 * Math.PI, false);
context.fill();
context.closePath();
}
context.globalAlpha = 1;
};
// Flare class
var Flare = function() {
this.x = random(-0.25, 1.25, true);
this.y = random(-0.25, 1.25, true);
this.z = random(0,2);
this.color = color;
this.opacity = random(0.001, 0.01, true);
};
Flare.prototype.render = function() {
var pos = position(this.x, this.y, this.z),
r = ((this.z * flareSizeMultiplier) + flareSizeBase) * (sizeRatio() / 1000);
// Feathered circles
/*
var grad = context.createRadialGradient(x+r,y+r,0,x+r,y+r,r);
grad.addColorStop(0, 'rgba(255,255,255,'+f.o+')');
grad.addColorStop(0.8, 'rgba(255,255,255,'+f.o+')');
grad.addColorStop(1, 'rgba(255,255,255,0)');
context.fillStyle = grad;
context.beginPath();
context.fillRect(x, y, r*2, r*2);
context.closePath();
*/
context.beginPath();
context.globalAlpha = this.opacity;
context.arc(pos.x, pos.y, r, 0, 2 * Math.PI, false);
context.fillStyle = this.color;
context.fill();
context.closePath();
context.globalAlpha = 1;
};
// Link class
var Link = function(startVertex, numPoints) {
this.length = numPoints;
this.verts = [startVertex];
this.stage = 0;
this.linked = [startVertex];
this.distances = [];
this.traveled = 0;
this.fade = 0;
this.finished = false;
};
Link.prototype.render = function() {
// Stages:
// 0. Vertex collection
// 1. Render line reaching from vertex to vertex
// 2. Fade out
// 3. Finished (delete me)
var i, p, pos, points;
switch (this.stage) {
// VERTEX COLLECTION STAGE
case 0:
// Grab the last member of the link
var last = particles[this.verts[this.verts.length-1]];
//console.log(JSON.stringify(last));
if (last && last.neighbors && last.neighbors.length > 0) {
// Grab a random neighbor
var neighbor = last.neighbors[random(0, last.neighbors.length-1)];
// If we haven't seen that particle before, add it to the link
if (this.verts.indexOf(neighbor) == -1) {
this.verts.push(neighbor);
}
// If we have seen that article before, we'll just wait for the next frame
}
else {
//console.log(this.verts[0]+' prematurely moving to stage 3 (0)');
this.stage = 3;
this.finished = true;
}
if (this.verts.length >= this.length) {
// Calculate all distances at once
for (i = 0; i < this.verts.length-1; i++) {
var p1 = particles[this.verts[i]],
p2 = particles[this.verts[i+1]],
dx = p1.x - p2.x,
dy = p1.y - p2.y,
dist = Math.sqrt(dx*dx + dy*dy);
this.distances.push(dist);
}
//console.log('Distances: '+JSON.stringify(this.distances));
//console.log('verts: '+this.verts.length+' distances: '+this.distances.length);
//console.log(this.verts[0]+' moving to stage 1');
this.stage = 1;
}
break;
// RENDER LINE ANIMATION STAGE
case 1:
if (this.distances.length > 0) {
points = [];
//var a = 1;
// Gather all points already linked
for (i = 0; i < this.linked.length; i++) {
p = particles[this.linked[i]];
pos = position(p.x, p.y, p.z);
points.push([pos.x, pos.y]);
}
var linkSpeedRel = linkSpeed * 0.00001 * canvas.width;
this.traveled += linkSpeedRel;
var d = this.distances[this.linked.length-1];
// Calculate last point based on linkSpeed and distance travelled to next point
if (this.traveled >= d) {
this.traveled = 0;
// We've reached the next point, add coordinates to array
//console.log(this.verts[0]+' reached vertex '+(this.linked.length+1)+' of '+this.verts.length);
this.linked.push(this.verts[this.linked.length]);
p = particles[this.linked[this.linked.length-1]];
pos = position(p.x, p.y, p.z);
points.push([pos.x, pos.y]);
if (this.linked.length >= this.verts.length) {
//console.log(this.verts[0]+' moving to stage 2 (1)');
this.stage = 2;
}
}
else {
// We're still travelling to the next point, get coordinates at travel distance
// http://math.stackexchange.com/a/85582
var a = particles[this.linked[this.linked.length-1]],
b = particles[this.verts[this.linked.length]],
t = d - this.traveled,
x = ((this.traveled * b.x) + (t * a.x)) / d,
y = ((this.traveled * b.y) + (t * a.y)) / d,
z = ((this.traveled * b.z) + (t * a.z)) / d;
pos = position(x, y, z);
//console.log(this.verts[0]+' traveling to vertex '+(this.linked.length+1)+' of '+this.verts.length+' ('+this.traveled+' of '+this.distances[this.linked.length]+')');
points.push([pos.x, pos.y]);
}
this.drawLine(points);
}
else {
//console.log(this.verts[0]+' prematurely moving to stage 3 (1)');
this.stage = 3;
this.finished = true;
}
break;
// FADE OUT STAGE
case 2:
if (this.verts.length > 1) {
if (this.fade < linkFade) {
this.fade++;
// Render full link between all vertices and fade over time
points = [];
var alpha = (1 - (this.fade / linkFade)) * linkOpacity;
for (i = 0; i < this.verts.length; i++) {
p = particles[this.verts[i]];
pos = position(p.x, p.y, p.z);
points.push([pos.x, pos.y]);
}
this.drawLine(points, alpha);
}
else {
//console.log(this.verts[0]+' moving to stage 3 (2a)');
this.stage = 3;
this.finished = true;
}
}
else {
//console.log(this.verts[0]+' prematurely moving to stage 3 (2b)');
this.stage = 3;
this.finished = true;
}
break;
// FINISHED STAGE
case 3:
default:
this.finished = true;
break;
}
};
Link.prototype.drawLine = function(points, alpha) {
if (typeof alpha !== 'number') alpha = linkOpacity;
if (points.length > 1 && alpha > 0) {
//console.log(this.verts[0]+': Drawing line '+alpha);
context.globalAlpha = alpha;
context.beginPath();
for (var i = 0; i < points.length-1; i++) {
context.moveTo(points[i][0], points[i][1]);
context.lineTo(points[i+1][0], points[i+1][1]);
}
context.strokeStyle = color;
context.lineWidth = lineWidth;
context.stroke();
context.closePath();
context.globalAlpha = 1;
}
};
// Utils
function noisePoint(i) {
var a = nAngle * i,
cosA = Math.cos(a),
sinA = Math.sin(a),
//value = simplex.noise2D(nScale * cosA + nScale, nScale * sinA + nScale),
//rad = nRad + value;
rad = nRad;
return {
x: rad * cosA,
y: rad * sinA
};
}
function position(x, y, z) {
return {
x: (x * canvas.width) + ((((canvas.width / 2) - mouse.x + ((nPos.x - 0.5) * noiseStrength)) * z) * motion),
y: (y * canvas.height) + ((((canvas.height / 2) - mouse.y + ((nPos.y - 0.5) * noiseStrength)) * z) * motion)
};
}
function sizeRatio() {
return canvas.width >= canvas.height ? canvas.width : canvas.height;
}
function random(min, max, float) {
return float ?
Math.random() * (max - min) + min :
Math.floor(Math.random() * (max - min + 1)) + min;
}
// init
if (canvas) init();
When I entered 'https://codepen.io/hduffin1/pen/QOMZJg', 'delaunay.js' is included in the setting.
Add the following script and it should work.
<script src="https://rawgit.com/ironwallaby/delaunay/master/delaunay.js"></script>
/**
* Stars
* Inspired by Steve Courtney's poster art for Celsius GS's Drifter - http://celsiusgs.com/drifter/posters.php
* by Cory Hughart - http://coryhughart.com
*/
// Settings
var particleCount = 40,
flareCount = 10,
motion = 0.05,
tilt = 0.05,
color = '#FFEED4',
particleSizeBase = 1,
particleSizeMultiplier = 0.5,
flareSizeBase = 100,
flareSizeMultiplier = 100,
lineWidth = 1,
linkChance = 75, // chance per frame of link, higher = smaller chance
linkLengthMin = 5, // min linked vertices
linkLengthMax = 7, // max linked vertices
linkOpacity = 0.25; // number between 0 & 1
linkFade = 90, // link fade-out frames
linkSpeed = 1, // distance a link travels in 1 frame
glareAngle = -60,
glareOpacityMultiplier = 0.05,
renderParticles = true,
renderParticleGlare = true,
renderFlares = true,
renderLinks = true,
renderMesh = false,
flicker = true,
flickerSmoothing = 15, // higher = smoother flicker
blurSize = 0,
orbitTilt = true,
randomMotion = true,
noiseLength = 1000,
noiseStrength = 1;
var canvas = document.getElementById('stars'),
//orbits = document.getElementById('orbits'),
context = canvas.getContext('2d'),
mouse = { x: 0, y: 0 },
m = {},
r = 0,
c = 1000, // multiplier for delaunay points, since floats too small can mess up the algorithm
n = 0,
nAngle = (Math.PI * 2) / noiseLength,
nRad = 100,
nScale = 0.5,
nPos = {x: 0, y: 0},
points = [],
vertices = [],
triangles = [],
links = [],
particles = [],
flares = [];
function init() {
var i, j, k;
// requestAnimFrame polyfill
window.requestAnimFrame = (function(){
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
function( callback ){
window.setTimeout(callback, 1000 / 60);
};
})();
// Fade in background
/*
var background = document.getElementById('background'),
bgImg = new Image(),
bgURL = '/img/background.jpg';
bgImg.onload = function() {
//console.log('background loaded');
background.style.backgroundImage = 'url("'+bgURL+'")';
background.className += ' loaded';
}
bgImg.src = bgURL;
*/
// Size canvas
resize();
mouse.x = canvas.clientWidth / 2;
mouse.y = canvas.clientHeight / 2;
// Create particle positions
for (i = 0; i < particleCount; i++) {
var p = new Particle();
particles.push(p);
points.push([p.x*c, p.y*c]);
}
//console.log(JSON.stringify(points));
// Delaunay triangulation
//var Delaunay = require('delaunay-fast');
vertices = Delaunay.triangulate(points);
//console.log(JSON.stringify(vertices));
// Create an array of "triangles" (groups of 3 indices)
var tri = [];
for (i = 0; i < vertices.length; i++) {
if (tri.length == 3) {
triangles.push(tri);
tri = [];
}
tri.push(vertices[i]);
}
//console.log(JSON.stringify(triangles));
// Tell all the particles who their neighbors are
for (i = 0; i < particles.length; i++) {
// Loop through all tirangles
for (j = 0; j < triangles.length; j++) {
// Check if this particle's index is in this triangle
k = triangles[j].indexOf(i);
// If it is, add its neighbors to the particles contacts list
if (k !== -1) {
triangles[j].forEach(function(value, index, array) {
if (value !== i && particles[i].neighbors.indexOf(value) == -1) {
particles[i].neighbors.push(value);
}
});
}
}
}
//console.log(JSON.stringify(particles));
if (renderFlares) {
// Create flare positions
for (i = 0; i < flareCount; i++) {
flares.push(new Flare());
}
}
// Motion mode
//if (Modernizr && Modernizr.deviceorientation) {
if ('ontouchstart' in document.documentElement && window.DeviceOrientationEvent) {
console.log('Using device orientation');
window.addEventListener('deviceorientation', function(e) {
mouse.x = (canvas.clientWidth / 2) - ((e.gamma / 90) * (canvas.clientWidth / 2) * 2);
mouse.y = (canvas.clientHeight / 2) - ((e.beta / 90) * (canvas.clientHeight / 2) * 2);
//console.log('Center: x:'+(canvas.clientWidth/2)+' y:'+(canvas.clientHeight/2));
//console.log('Orientation: x:'+mouse.x+' ('+e.gamma+') y:'+mouse.y+' ('+e.beta+')');
}, true);
}
else {
// Mouse move listener
console.log('Using mouse movement');
document.body.addEventListener('mousemove', function(e) {
//console.log('moved');
mouse.x = e.clientX;
mouse.y = e.clientY;
});
}
// Random motion
if (randomMotion) {
//var SimplexNoise = require('simplex-noise');
//var simplex = new SimplexNoise();
}
// Animation loop
(function animloop(){
requestAnimFrame(animloop);
resize();
render();
})();
}
function render() {
if (randomMotion) {
n++;
if (n >= noiseLength) {
n = 0;
}
nPos = noisePoint(n);
//console.log('NOISE x:'+nPos.x+' y:'+nPos.y);
}
// Clear
context.clearRect(0, 0, canvas.width, canvas.height);
if (blurSize > 0) {
context.shadowBlur = blurSize;
context.shadowColor = color;
}
if (renderParticles) {
// Render particles
for (var i = 0; i < particleCount; i++) {
particles[i].render();
}
}
if (renderMesh) {
// Render all lines
context.beginPath();
for (var v = 0; v < vertices.length-1; v++) {
// Splits the array into triplets
if ((v + 1) % 3 === 0) { continue; }
var p1 = particles[vertices[v]],
p2 = particles[vertices[v+1]];
//console.log('Line: '+p1.x+','+p1.y+'->'+p2.x+','+p2.y);
var pos1 = position(p1.x, p1.y, p1.z),
pos2 = position(p2.x, p2.y, p2.z);
context.moveTo(pos1.x, pos1.y);
context.lineTo(pos2.x, pos2.y);
}
context.strokeStyle = color;
context.lineWidth = lineWidth;
context.stroke();
context.closePath();
}
if (renderLinks) {
// Possibly start a new link
if (random(0, linkChance) == linkChance) {
var length = random(linkLengthMin, linkLengthMax);
var start = random(0, particles.length-1);
startLink(start, length);
}
// Render existing links
// Iterate in reverse so that removing items doesn't affect the loop
for (var l = links.length-1; l >= 0; l--) {
if (links[l] && !links[l].finished) {
links[l].render();
}
else {
delete links[l];
}
}
}
if (renderFlares) {
// Render flares
for (var j = 0; j < flareCount; j++) {
flares[j].render();
}
}
/*
if (orbitTilt) {
var tiltX = -(((canvas.clientWidth / 2) - mouse.x + ((nPos.x - 0.5) * noiseStrength)) * tilt),
tiltY = (((canvas.clientHeight / 2) - mouse.y + ((nPos.y - 0.5) * noiseStrength)) * tilt);
orbits.style.transform = 'rotateY('+tiltX+'deg) rotateX('+tiltY+'deg)';
}
*/
}
function resize() {
canvas.width = window.innerWidth * (window.devicePixelRatio || 1);
canvas.height = canvas.width * (canvas.clientHeight / canvas.clientWidth);
}
function startLink(vertex, length) {
//console.log('LINK from '+vertex+' (length '+length+')');
links.push(new Link(vertex, length));
}
// Particle class
var Particle = function() {
this.x = random(-0.1, 1.1, true);
this.y = random(-0.1, 1.1, true);
this.z = random(0,4);
this.color = color;
this.opacity = random(0.1,1,true);
this.flicker = 0;
this.neighbors = []; // placeholder for neighbors
};
Particle.prototype.render = function() {
var pos = position(this.x, this.y, this.z),
r = ((this.z * particleSizeMultiplier) + particleSizeBase) * (sizeRatio() / 1000),
o = this.opacity;
if (flicker) {
var newVal = random(-0.5, 0.5, true);
this.flicker += (newVal - this.flicker) / flickerSmoothing;
if (this.flicker > 0.5) this.flicker = 0.5;
if (this.flicker < -0.5) this.flicker = -0.5;
o += this.flicker;
if (o > 1) o = 1;
if (o < 0) o = 0;
}
context.fillStyle = this.color;
context.globalAlpha = o;
context.beginPath();
context.arc(pos.x, pos.y, r, 0, 2 * Math.PI, false);
context.fill();
context.closePath();
if (renderParticleGlare) {
context.globalAlpha = o * glareOpacityMultiplier;
/*
context.ellipse(pos.x, pos.y, r * 30, r, 90 * (Math.PI / 180), 0, 2 * Math.PI, false);
context.fill();
context.closePath();
*/
context.ellipse(pos.x, pos.y, r * 100, r, (glareAngle - ((nPos.x - 0.5) * noiseStrength * motion)) * (Math.PI / 180), 0, 2 * Math.PI, false);
context.fill();
context.closePath();
}
context.globalAlpha = 1;
};
// Flare class
var Flare = function() {
this.x = random(-0.25, 1.25, true);
this.y = random(-0.25, 1.25, true);
this.z = random(0,2);
this.color = color;
this.opacity = random(0.001, 0.01, true);
};
Flare.prototype.render = function() {
var pos = position(this.x, this.y, this.z),
r = ((this.z * flareSizeMultiplier) + flareSizeBase) * (sizeRatio() / 1000);
// Feathered circles
/*
var grad = context.createRadialGradient(x+r,y+r,0,x+r,y+r,r);
grad.addColorStop(0, 'rgba(255,255,255,'+f.o+')');
grad.addColorStop(0.8, 'rgba(255,255,255,'+f.o+')');
grad.addColorStop(1, 'rgba(255,255,255,0)');
context.fillStyle = grad;
context.beginPath();
context.fillRect(x, y, r*2, r*2);
context.closePath();
*/
context.beginPath();
context.globalAlpha = this.opacity;
context.arc(pos.x, pos.y, r, 0, 2 * Math.PI, false);
context.fillStyle = this.color;
context.fill();
context.closePath();
context.globalAlpha = 1;
};
// Link class
var Link = function(startVertex, numPoints) {
this.length = numPoints;
this.verts = [startVertex];
this.stage = 0;
this.linked = [startVertex];
this.distances = [];
this.traveled = 0;
this.fade = 0;
this.finished = false;
};
Link.prototype.render = function() {
// Stages:
// 0. Vertex collection
// 1. Render line reaching from vertex to vertex
// 2. Fade out
// 3. Finished (delete me)
var i, p, pos, points;
switch (this.stage) {
// VERTEX COLLECTION STAGE
case 0:
// Grab the last member of the link
var last = particles[this.verts[this.verts.length-1]];
//console.log(JSON.stringify(last));
if (last && last.neighbors && last.neighbors.length > 0) {
// Grab a random neighbor
var neighbor = last.neighbors[random(0, last.neighbors.length-1)];
// If we haven't seen that particle before, add it to the link
if (this.verts.indexOf(neighbor) == -1) {
this.verts.push(neighbor);
}
// If we have seen that particle before, we'll just wait for the next frame
}
else {
//console.log(this.verts[0]+' prematurely moving to stage 3 (0)');
this.stage = 3;
this.finished = true;
}
if (this.verts.length >= this.length) {
// Calculate all distances at once
for (i = 0; i < this.verts.length-1; i++) {
var p1 = particles[this.verts[i]],
p2 = particles[this.verts[i+1]],
dx = p1.x - p2.x,
dy = p1.y - p2.y,
dist = Math.sqrt(dx*dx + dy*dy);
this.distances.push(dist);
}
//console.log('Distances: '+JSON.stringify(this.distances));
//console.log('verts: '+this.verts.length+' distances: '+this.distances.length);
//console.log(this.verts[0]+' moving to stage 1');
this.stage = 1;
}
break;
// RENDER LINE ANIMATION STAGE
case 1:
if (this.distances.length > 0) {
points = [];
//var a = 1;
// Gather all points already linked
for (i = 0; i < this.linked.length; i++) {
p = particles[this.linked[i]];
pos = position(p.x, p.y, p.z);
points.push([pos.x, pos.y]);
}
var linkSpeedRel = linkSpeed * 0.00001 * canvas.width;
this.traveled += linkSpeedRel;
var d = this.distances[this.linked.length-1];
// Calculate last point based on linkSpeed and distance travelled to next point
if (this.traveled >= d) {
this.traveled = 0;
// We've reached the next point, add coordinates to array
//console.log(this.verts[0]+' reached vertex '+(this.linked.length+1)+' of '+this.verts.length);
this.linked.push(this.verts[this.linked.length]);
p = particles[this.linked[this.linked.length-1]];
pos = position(p.x, p.y, p.z);
points.push([pos.x, pos.y]);
if (this.linked.length >= this.verts.length) {
//console.log(this.verts[0]+' moving to stage 2 (1)');
this.stage = 2;
}
}
else {
// We're still travelling to the next point, get coordinates at travel distance
// http://math.stackexchange.com/a/85582
var a = particles[this.linked[this.linked.length-1]],
b = particles[this.verts[this.linked.length]],
t = d - this.traveled,
x = ((this.traveled * b.x) + (t * a.x)) / d,
y = ((this.traveled * b.y) + (t * a.y)) / d,
z = ((this.traveled * b.z) + (t * a.z)) / d;
pos = position(x, y, z);
//console.log(this.verts[0]+' traveling to vertex '+(this.linked.length+1)+' of '+this.verts.length+' ('+this.traveled+' of '+this.distances[this.linked.length]+')');
points.push([pos.x, pos.y]);
}
this.drawLine(points);
}
else {
//console.log(this.verts[0]+' prematurely moving to stage 3 (1)');
this.stage = 3;
this.finished = true;
}
break;
// FADE OUT STAGE
case 2:
if (this.verts.length > 1) {
if (this.fade < linkFade) {
this.fade++;
// Render full link between all vertices and fade over time
points = [];
var alpha = (1 - (this.fade / linkFade)) * linkOpacity;
for (i = 0; i < this.verts.length; i++) {
p = particles[this.verts[i]];
pos = position(p.x, p.y, p.z);
points.push([pos.x, pos.y]);
}
this.drawLine(points, alpha);
}
else {
//console.log(this.verts[0]+' moving to stage 3 (2a)');
this.stage = 3;
this.finished = true;
}
}
else {
//console.log(this.verts[0]+' prematurely moving to stage 3 (2b)');
this.stage = 3;
this.finished = true;
}
break;
// FINISHED STAGE
case 3:
default:
this.finished = true;
break;
}
};
Link.prototype.drawLine = function(points, alpha) {
if (typeof alpha !== 'number') alpha = linkOpacity;
if (points.length > 1 && alpha > 0) {
//console.log(this.verts[0]+': Drawing line '+alpha);
context.globalAlpha = alpha;
context.beginPath();
for (var i = 0; i < points.length-1; i++) {
context.moveTo(points[i][0], points[i][1]);
context.lineTo(points[i+1][0], points[i+1][1]);
}
context.strokeStyle = color;
context.lineWidth = lineWidth;
context.stroke();
context.closePath();
context.globalAlpha = 1;
}
};
// Utils
function noisePoint(i) {
var a = nAngle * i,
cosA = Math.cos(a),
sinA = Math.sin(a),
//value = simplex.noise2D(nScale * cosA + nScale, nScale * sinA + nScale),
//rad = nRad + value;
rad = nRad;
return {
x: rad * cosA,
y: rad * sinA
};
}
function position(x, y, z) {
return {
x: (x * canvas.width) + ((((canvas.width / 2) - mouse.x + ((nPos.x - 0.5) * noiseStrength)) * z) * motion),
y: (y * canvas.height) + ((((canvas.height / 2) - mouse.y + ((nPos.y - 0.5) * noiseStrength)) * z) * motion)
};
}
function sizeRatio() {
return canvas.width >= canvas.height ? canvas.width : canvas.height;
}
function random(min, max, float) {
return float ?
Math.random() * (max - min) + min :
Math.floor(Math.random() * (max - min + 1)) + min;
}
// init
if (canvas) init();
html,
body {
margin: 0;
padding: 0;
}
body {
background-color: #31102F;
background: radial-gradient(ellipse at center, #31102f 0%, #280b29 100%);
}
#stars {
display: block;
position: relative;
width: 100%;
height: 16rem;
height: 100vh;
z-index: 1;
}
<script src="https://rawgit.com/ironwallaby/delaunay/master/delaunay.js"></script>
<canvas id="stars" width="300" height="300"></canvas>

How would I handle sideways collisions in two dimensions?

I've been experimenting with the html element.
I'm trying to make a 2d sidescroller game and I've been having issues with collisions on the sides of objects.
Walking on the top of objects works just fine and hitting the bottom of objects also works but I cannot get colliding with the side of an object to work. I've made dozens of attempts which all end up introducing dozens of new bugs while also not fixing the problem.
Here's the code
<html>
<canvas id="canvas" width="200" height="200" style="border-style:solid; border-width:1px"></canvas>
<script>if (typeof module === 'object') { window.module = module; module = undefined; }</script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script>if (window.module) module = window.module;</script>
<span id="x"></span>
<span id="y"></span>
<br>
<br>
<span id="test"></span>
<script>
let canvas = document.getElementById("canvas");
let ctx = canvas.getContext("2d");
function clear() {
ctx.fillStyle = "#FFFFFF"
ctx.fillRect(0, 0, 200, 200);
ctx.fillStyle = "#000000"
}
let keys = {};
$(document).keydown(function (e) { //Records keystrokes
keys[e.which] = true;
})
$(document).keyup(function (e) {
delete keys[e.which];
});
let worldx = 10;
const x = 90;
let y = 0;
let yVel = 0;
let grounded = false;
let objects = { //I'm representing the game world as an array of boxes
"boxes": [
{ "width": 50, "height": 10, "x": 45, "y": 100 },
{ "width": 75, "height": 20, "x": 60, "y": 150 },
{ "width": 10, "height": 100, "x": 125, "y": 40 }
]
}
let id = window.setInterval(function () { //Lock it at ~60fps
clear();
$("span").empty();
ctx.fillRect(x, y, 10, 20) //Player character
yVel += 9.8 * 0.016 // force of gravity
y += yVel
for (let check = 0; check != objects.boxes.length; check++) { //Loop through objects
if (y >= objects.boxes[check].y - 20 && y <= objects.boxes[check].y + objects.boxes[check].height && x < objects.boxes[check].x + worldx + objects.boxes[check].width && x >= objects.boxes[check].x - 10 + worldx) { //Check if there is a collision.
yVel = 0;
//TODO add something here that will handle side-on collisions
if (y <= objects.boxes[check].y + objects.boxes[check].height / 2) {
y = objects.boxes[check].y - 20
grounded = true
}
else {
y = objects.boxes[check].y + objects.boxes[check].height
}
}
ctx.fillRect(objects.boxes[check].x + worldx, objects.boxes[check].y, objects.boxes[check].width, objects.boxes[check].height) // draw object
}
$("#x").append(Math.floor(x - worldx) + ", ")
$("#y").append(Math.floor(y))
for (i in keys) {
if (!keys.hasOwnProperty(i)) { continue; }
if (i == 32 && grounded) { //Space bar
yVel -= 5;
grounded = false;
}
if (i == 65) { //A
worldx += 3;
}
if (i == 68) { //D
worldx -= 3;
}
}
}, 16)
</script>
</html>
The TODO comment is where I check for collisions.
Here is a good start for you(this code is from scratch, yours is a little tricky for me to understand):
var px = 0;//player's x and y
var py = 0;
var velX = 0;
var velY = 0;
var grounded = false;
var pw = 20;//player's width
var ph = 20;//player's height
var block = function(x, y, w, h) {
if (px + pw > x && px < x + w && py + ph > y && py + ph < y + 5 && velY > 0) {//Top
velY = 0;
grounded = true;
py = y - ph;
}
if (px + pw > x && px < x + w && py < y + h && py > y + h - 5 && velY < 0) {//bottom
velY = 2;//bonk
py = y + h;
}
if (px + pw > x && px < x + 5 && py + ph > y && py < y + h && velX > 0) {//left
velX = 0;
px = x - pw;
}
if (px > x + w - 5 && px < x + w && py + ph > y && py < y + h && velX < 0) {//right
velX = 0;
px = x + w;
}
};

Can't read property 'addEventListener' of null

I am working on a college project that requires me to build a 2D game in javascript. A problem that I'm having at the moment is that it cannot read the 'addEventListener'. This error has caused my game to not work completely.
document.getElementById('restart').addEventListener('click', startGame);
Here is the full code that I have used. The error is down the very bottom.
(function()
{
//Define variables
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
var player, score, stop, ticker;
var ground = [], water = [], enemies = [], environment = [];
//Platform variables
var platformHeight, platformLength, gapLength;
var platformWidth = 32;
var platformBase = canvas.height - platformWidth;
var platformSpacer = 64;
//Randomly generates a number
function random(low, high)
{
return Math.floor(Math.random() * (high - low + 1) + low);
}
//Bounds a number
function bound(num, low, high)
{
return Math.max(Math.min(num, high), low);
}
//Loads all of the assets
var assetLoader = (function()
{
this.imgs = {
'bg' : 'Images/bg.png',
'sky' : 'Images/sky.png',
'backdrop' : 'Images/backdrop.png',
'backdrop2' : 'Images/backdrop_ground.png',
'grass' : 'Images/grass.png',
'avatar_normal' : 'Images/normal_walk.png',
'water' : 'imgs/water.png',
'grass1' : 'imgs/grassMid1.png',
'grass2' : 'imgs/grassMid2.png',
'bridge' : 'imgs/bridge.png',
'plant' : 'imgs/plant.png',
'bush1' : 'imgs/bush1.png',
'bush2' : 'imgs/bush2.png',
'cliff' : 'imgs/grassCliffRight.png',
'spikes' : 'imgs/spikes.png',
'box' : 'imgs/boxCoin.png',
'slime' : 'imgs/slime.png'
};
var assetsLoaded = 0; //How many assets have been loaded
var numImgs = Object.keys(this.imgs).length; //Total number of image assets
this.totalAssest = numImgs; //Total number of assets
function assetLoaded(dic, name)
{
if(this[dic][name].status !== 'loading')
{
return;
}
this[dic][name].status = 'loaded';
assetsLoaded++;
if(assetsLoaded === this.totalAssest && typeof this.finished === 'function')
{
this.finished();
}
}
this.downloadAll = function()
{
var _this = this;
var src;
for (var img in this.imgs)
{
if (this.imgs.hasOwnProperty(img))
{
src = this.imgs[img];
(function(_this, img)
{
_this.imgs[img] = new Image();
_this.imgs[img].status = 'loading';
_this.imgs[img].name = img;
_this.imgs[img].onload = function() {assetLoaded.call(_this, 'imgs', img)};
_this.imgs[img].src = src;
})(_this, img);
}
}
}
return{
imgs: this.imgs,
totalAssest: this.totalAssest,
downloadAll: this.downloadAll
};
})();
assetLoader.finished = function()
{
startGame();
}
function SpriteSheet(path, frameWidth, frameHeight)
{
this.image = new Image();
this.frameWidth = frameWidth;
this.frameHeight = frameHeight;
var self = this;
this.image.onload = function()
{
self.framesPerRow = Math.floor(self.image.width / self.frameWidth);
};
this.image.src = path;
}
function Animation(spritesheet, frameSpeed, startFrame, endFrame)
{
var animationSequence = [];
var currentFrame = 0;
var counter = 0;
for (var frameNumber = startFrame; frameNumber <= endFrame; frameNumber++)
{
animationSequence.push(frameNumber);
}
this.update = function()
{
if (counter == (frameSpeed - 1))
{
currentFrame = (currentFrame + 1) % animationSequence.length;
}
counter = (counter + 1) % frameSpeed;
};
this.draw = function(x, y)
{
var row = Math.floor(animationSequence[currentFrame] / spritesheet.framesPerRow);
var col = Math.floor(animationSequence[currentFrame] % spritesheet.framesPerRow);
ctx.drawImage
(
spritesheet.image,
col * spritesheet.frameWidth, row * spritesheet.frameHeight,
spritesheet.frameWidth, spritesheet.frameHeight,
x, y,
spritesheet.frameWidth, spritesheet.frameHeight);
};
}
var background = (function()
{
var sky = {};
var backdrop = {};
var backdrop2 = {};
this.draw = function()
{
ctx.drawImage(assetLoader.imgs.bg, 0, 0);
sky.x -= sky.speed;
backdrop.x -= backdrop.speed;
backdrop2.x -= backdrop2.speed;
ctx.drawImage(assetLoader.imgs.sky, sky.x, sky.y);
ctx.drawImage(assetLoader.imgs.sky, sky.x + canvas.width, sky.y);
ctx.drawImage(assetLoader.imgs.backdrop, backdrop.x, backdrop.y);
ctx.drawImage(assetLoader.imgs.backdrop, backdrop.x + canvas.width, backdrop.y);
ctx.drawImage(assetLoader.imgs.backdrop2, backdrop2.x, backdrop2.y);
ctx.drawImage(assetLoader.imgs.backdrop2, backdrop2.x + canvas.width, backdrop2.y);
if (sky.x + assetLoader.imgs.sky.width <= 0)
{
sky.x = 0;
}
if (backdrop.x + assetLoader.imgs.backdrop.width <= 0)
{
backdrop.x = 0;
}
if (backdrop2.x + assetLoader.imgs.backdrop2.width <= 0)
{
backdrop2.x = 0;
}
};
this.reset = function()
{
sky.x = 0;
sky.y = 0;
sky.speed = 0.2;
backdrop.x = 0;
backdrop.y = 0;
backdrop.speed = 0.4;
backdrop2.x = 0;
backdrop2.y = 0;
backdrop2.speed = 0.6;
}
return{
draw: this.draw,
reset: this.reset
};
})();
//A vector for 2D space
function Vector(x, y, dx, dy)
{
// position
this.x = x || 0;
this.y = y || 0;
// direction
this.dx = dx || 0;
this.dy = dy || 0;
}
//Advances the vector's position
Vector.prototype.advance = function()
{
this.x += this.dx;
this.y += this.dy;
};
//Gets the minimum distance between two vectors
Vector.prototype.minDist = function(vec)
{
var minDist = Infinity;
var max = Math.max(Math.abs(this.dx), Math.abs(this.dy),Math.abs(vec.dx), Math.abs(vec.dy));
var slice = 1 / max;
var x, y, distSquared;
// get the middle of each vector
var vec1 = {}, vec2 = {};
vec1.x = this.x + this.width/2;
vec1.y = this.y + this.height/2;
vec2.x = vec.x + vec.width/2;
vec2.y = vec.y + vec.height/2;
for(var percent = 0; percent < 1; percent += slice)
{
x = (vec1.x + this.dx * percent) - (vec2.x + vec.dx * percent);
y = (vec1.y + this.dy * percent) - (vec2.y + vec.dy * percent);
distSquared = x * x + y * y;
minDist = Math.min(minDist, distSquared);
}
return Math.sqrt(minDist);
};
//The player object
var player = (function(player)
{
//Player properties
player.width = 60;
player.height = 96;
player.speed = 6;
//Jumping
player.gravity = 1;
player.dy = 0;
player.jumpDy = -10;
player.isFalling = false;
player.isJumping = false;
//Spritesheets
player.sheet = new SpriteSheet('Images/normal_walk.png', player.width, player.height);
player.walkAnim = new Animation(player.sheet, 4, 0, 15);
player.jumpAnim = new Animation(player.sheet, 4, 15, 15);
player.fallAnim = new Animation(player.sheet, 4, 11, 11);
player.anim = player.walkAnim;
Vector.call(player, 0, 0, 0, player.dy);
var jumpCounter = 0;
player.update = function()
{
//Jump if not currently jumping or falling
if(KEY_STATUS.space && player.dy === 0 && !player.isJumping)
{
player.isJumping = true;
player.dy = player.jumpDy;
jumpCounter = 12;
}
//Jump higher if the spacebar is continually pressed
if(KEY_STATUS.space && jumpCounter)
{
player.dy = player.jumpDy;
}
jumpCounter = Math.max(jumpCounter - 1, 0);
this.advance();
//Gravity
if(player.isFalling || player.isJumping)
{
player.dy += player.gravity;
}
//Falling Animation
if(player.dy > 0)
{
player.anim = player.fallAnim;
}
// change animation is jumping
else if(player.dy < 0)
{
player.anim = player.jumpAnim;
}
else
{
player.anim = player.walkAnim;
}
player.anim.update();
};
//Draw the player's current position
player.draw = function()
{
player.anim.draw(player.x, player.y);
};
//Resets the player's position
player.reset = function()
{
player.x = 64;
player.y = 250;
};
return player;
})(Object.create(Vector.prototype));
//Sprites
function Sprite(x, y, type)
{
this.x = x;
this.y = y;
this.width = platformWidth;
this.height = platformWidth;
this.type = type;
Vector.call(this, x, y, 0, 0);
//Updating the sprites
this.update = function()
{
this.dx = -player.speed;
this.advancer();
}
//Drawing the sprites
this.draw = function()
{
ctx.save();
ctx.translate(0.5, 0.5);
ctx.drawImage(assetLoader.imgs[this.type], this.x, this.y);
ctx.restore();
}
}
Sprite.prototype = Object.create(Vector.prototype);
//Platforms
function getType()
{
var type;
switch(platformHeight)
{
case 0:
case 1:
type = Math.random() > 0.5 ? 'grass1' : 'grass2';
break;
case 2:
type = 'grass';
break;
case 3:
type = 'bridge';
break;
case 4:
type = 'box';
break;
}
if (platformLength === 1 && platformHeight < 3 && rand(0, 3) === 0)
{
type = 'cliff';
}
return type;
}
//Update and draw all ground positions
function updateGround()
{
//Animate ground
player.isFalling = true;
for(var i = 0; i < ground.length; i++)
{
ground[i].update();
ground[i].draw();
//Stop the player going through the platforms when landing
var angle;
if(player.minDist(ground[i]) <= player.height/2 + platformWidth/2 && (angle = Math.atan2(player.y - ground[i].y, player.x - ground[i].x) * 180/Math.PI) > -130 &&angle < -50)
{
player.isJumping = false;
player.isFalling = false;
player.y = ground[i].y - player.height + 5;
player.dy = 0;
}
}
//Remove the ground that has gone off screen
if(ground[0] && ground[0].x < -platformWidth)
{
ground.splice(0, 1);
}
}
//Update and draw all water positions
function updateWater()
{
//Animate water
for(var i = 0; i < water.length; i++)
{
water[i].update();
water[i].draw();
}
//Remove water that has gone off screen
if (water[0] && water[0].x < -platformWidth)
{
var w = water.splice(0, 1)[0];
w.x = water[water.length-1].x + platformWidth;
water.push(w);
}
}
//Update and draw all environment positions
function updateEnvironment()
{
//Animate environment
for(var i = 0; i < environment.length; i++)
{
environment[i].update();
environment[i].draw();
}
//R emove environment that have gone off screen
if(environment[0] && environment[0].x < -platformWidth)
{
environment.splice(0, 1);
}
}
//Update and draw all enemies position. Also check for collision against the player.
function updateEnemies()
{
//Animate enemies
for(var i = 0; i < enemies.length; i++)
{
enemies[i].update();
enemies[i].draw();
//Player ran into enemy
if(player.minDist(enemies[i]) <= player.width - platformWidth/2)
{
gameOver();
}
}
//Remove enemies that have gone off screen
if(enemies[0] && enemies[0].x < -platformWidth)
{
enemies.splice(0, 1);
}
}
//Update and draw the players position
function updatePlayer()
{
player.update();
player.draw();
//Game over
if(player.y + player.height >= canvas.height)
{
gameOver();
}
}
//Spawn new sprites off screen
function spawnSprites()
{
//Increase score
score++;
//First create a gap
if(gapLength > 0)
{
gapLength--;
}
//Then create the ground
else if(platformLength > 0)
{
var type = getType();
ground.push(new Sprite(
canvas.width + platformWidth % player.speed,
platformBase - platformHeight * platformSpacer,
type
));
platformLength--;
//Add random environment sprites
spawnEnvironmentSprites();
//Add random enemies
spawnEnemySprites();
}
//Start over
else
{
//Increase gap length every speed increase of 4
gapLength = rand(player.speed - 2, player.speed);
// only allow a ground to increase by 1
platformHeight = bound(rand(0, platformHeight + rand(0, 2)), 0, 4);
platformLength = rand(Math.floor(player.speed/2), player.speed * 4);
}
}
//Spawn new environment sprites off screen
function spawnEnvironmentSprites()
{
if(score > 40 && rand(0, 20) === 0 && platformHeight < 3)
{
if (Math.random() > 0.5)
{
environment.push(new Sprite(canvas.width + platformWidth % player.speed, platformBase - platformHeight * platformSpacer - platformWidth, 'plant'));
}
else if(platformLength > 2)
{
environment.push(new Sprite(canvas.width + platformWidth % player.speed, platformBase - platformHeight * platformSpacer - platformWidth, 'bush1'));
environment.push(new Sprite(canvas.width + platformWidth % player.speed + platformWidth, platformBase - platformHeight * platformSpacer - platformWidth, 'bush2'));
}
}
}
//Spawn new enemy sprites off screen
function spawnEnemySprites()
{
if(score > 100 && Math.random() > 0.96 && enemies.length < 3 && platformLength > 5 && (enemies.length ? canvas.width - enemies[enemies.length-1].x >= platformWidth * 3 || canvas.width - enemies[enemies.length-1].x < platformWidth : true))
{
enemies.push(new Sprite(canvas.width + platformWidth % player.speed, platformBase - platformHeight * platformSpacer - platformWidth, Math.random() > 0.5 ? 'spikes' : 'slime'));
}
}
//Game Loop
function animate()
{
if(!stop)
{
requestAnimFrame(animate);
ctx.clearRect(0, 0, canvas.width, canvas.height);
background.draw();
//Update entities
updateWater();
updateEnvironment();
updatePlayer();
updateGround();
updateEnemies();
//Draw the score
ctx.fillText('Score: ' + score + 'm', canvas.width - 140, 30);
//Spawn a new Sprite
if(ticker % Math.floor(platformWidth / player.speed) === 0)
{
spawnSprites();
}
//Increase player's speed only when player is jumping
if(ticker > (Math.floor(platformWidth / player.speed) * player.speed * 20) && player.dy !== 0)
{
player.speed = bound(++player.speed, 0, 15);
player.walkAnim.frameSpeed = Math.floor(platformWidth / player.speed) - 1;
//Reset ticker
ticker = 0;
//Spawn a platform to fill in gap created by increasing player speed
if(gapLength === 0)
{
var type = getType();
ground.push(new Sprite(canvas.width + platformWidth % player.speed, platformBase - platformHeight * platformSpacer, type));
platformLength--;
}
}
ticker++;
}
}
//Spacebar events
var KEY_CODES = {
32: 'space'
};
var KEY_STATUS = {};
for(var code in KEY_CODES)
{
if(KEY_CODES.hasOwnProperty(code))
{
KEY_STATUS[KEY_CODES[code]] = false;
}
}
document.onkeydown - function(e)
{
var keyCode = (e.keyCode) ? e.keyCode : e.charCode;
if(KEY_CODES[keyCode])
{
e.preventDefault();
KEY_STATUS[KEY_CODES[keyCode]] = true;
}
};
document.onkeydown - function(e)
{
var keyCode = (e.keyCode) ? e.keyCode : e.charCode;
if(KEY_CODES[keyCode])
{
e.preventDefault();
KEY_STATUS[KEY_CODES[keyCode]] = false;
}
};
//Request Animation Polyfill
var requestAnimFrame = (function()
{
return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(callback, element)
{
window.setTimeout(callback, 1000 / 60);
};
})();
//Start the game and resets all variables and entities, spawn ground and water.
function startGame()
{
document.getElementById('game-over').style.display = 'none';
ground = [];
water = [];
environment = [];
enemies = [];
player.reset();
ticker = 0;
stop = false;
score = 0;
platformHeight = 2;
platformLength = 15;
gapLength = 0;
ctx.font = '16px arial, sans-serif';
for (var i = 0; i < 30; i++)
{
ground.push(new Sprite(i * (platformWidth-3), platformBase - platformHeight * platformSpacer, 'grass'));
}
for (i = 0; i < canvas.width / 32 + 2; i++)
{
water.push(new Sprite(i * platformWidth, platformBase, 'water'));
}
background.reset();
animate();
}
//End the game and restart
function gameOver()
{
stop = true;
document.getElementById('game-over').style.display = 'block';
}
document.getElementById('restart').addEventListener('click', startGame);
assetLoader.downloadAll();
})();

Javascript line and point angle collision

I want to move the balls in correct direction when bat collide with them, like in this example
It doesn't have to be this good though. Working correctly is the goal here.
So far, what I've got can be seen in the following url:
https://jsfiddle.net/qphqvntx/4/
The problem is with the collision, when bat hit the balls. It's behaving very weird.
//Canvas Variable
var mainCanvas = document.getElementById("mainCanvas");
var ctx = mainCanvas.getContext("2d");
var canvasHeight = mainCanvas.height;
var canvasWidth = mainCanvas.width;
var borderRadius = 10;
var bottomRadius = 120;
var gravity = 0.2;
var animate = false;
//Ball Object related variable
var balls = [];
var ballObj = {
x: 0,
y: 0,
velocity: {x: 0, y: 0},
};
var ball = '';
var debugBall = '';
var ballRadius = 10;
var dumping = 0.99;
var ballSpeed = 6;
var force = 1.8;
var setBallTimer = 150;
var updateBallTimer = 0;
var target;
var distanceX;
var distancey;
var j, balls2;
//Bat related variable
var batXPos = 200;
var batYPos = canvasHeight - bottomRadius - 120;
var batHeight = 100;
var batWidth = 10;
var mouse = [0, 0];
var point = [170, 175];
var dx, dy;
//run related variable
var oneRunLine = 60;
var twoRunLine = 90;
var fourRunLine = 100;
var outTopLine = 450;
var oneRunChain = canvasHeight - bottomRadius;
var twoRunChain = canvasHeight - bottomRadius - oneRunLine;
var fourRunChain = canvasHeight - bottomRadius - oneRunLine - twoRunLine;
var sixRunChain = canvasHeight - bottomRadius - oneRunLine - twoRunLine - fourRunLine;
var circleUnderMouse;
var mouse = {
x: 0,
y: 0,
down: false
}
var res;
var previousEvent = false;
function executeFrame() {
if (animate) {
requestAnimFrame(executeFrame);
}
ctx.lineWidth = "3";
ctx.strokeRect(0, 0, mainCanvas.width, mainCanvas.height);
ctx.strokeRect(0, 0, mainCanvas.width, mainCanvas.height - bottomRadius);
ctx.fillStyle = 'rgba(255,255,255,0.3)';
ctx.fillRect(0, 0, mainCanvas.width, mainCanvas.height);
update();
if (balls.length != '0') {
balls.forEach(function (ball, j, i) {
drawBall(ball);
createBat();
});
}
}
initializeGame();
function update() {
if (balls.length != '0') {
balls.forEach(function (ball, balli, ballj) {
ball.addGravity();
ball.velocity.y *= dumping;
ball.velocity.x *= dumping;
ball.y += ball.velocity.y;
ball.x += ball.velocity.x * force;
if (hitGround(ball) == true) {
ball.y = mainCanvas.height - bottomRadius;
ball.velocity.y = -Math.abs(ball.velocity.y);
}
if (hitLeft(ball) == true) {
ball.velocity.x = Math.abs(ball.velocity.x);
}
var hit = linePoint(point[0], point[1], mouse[0], mouse[1], ball.x, ball.y, ball);
if (hit == true) {
//console.log("hit");
} else {
//console.log("not yet");
}
for (j = balli + 1; j < balls.length; j++) {
balls2 = ballj[j];
var dx = balls2.x - ball.x;
var dy = balls2.y - ball.y;
var d = Math.sqrt(dx * dx + dy * dy);
if (d < 2 * ballRadius) {
if (d === 0) {
d = 0.1;
}
var unitX = dx / d;
var unitY = dy / d;
var newForce = -1;
var forceX = unitX * newForce;
var forceY = unitY * newForce;
ball.velocity.x += forceX;
ball.velocity.y += forceY;
balls2.velocity.x -= forceX;
balls2.velocity.y -= forceY;
}
}
});
}
updateBallTimer++;
if (updateBallTimer >= setBallTimer) {
createBall();
updateBallTimer = 0;
}
}
function initializeGame() {
createBall();
createBat();
}
function createBall() {
randomPoint(50, 150);
ball = instantiateBall(canvasWidth, target.y, ballObj);
ball.velocity.x -= getRandomNumber(4, 6);
}
function instantiateBall(xPos, yPos, ball) {
ball = {
x: xPos,
y: yPos,
velocity: {x: 0, y: 0},
addGravity: function () {
return this.velocity.y += gravity;
},
onCanvas: false
};
balls.push(ball);
drawBall(ball);
return ball;
}
function drawBall(ball) {
if (ball != '') {
ctx.beginPath();
ctx.arc(ball.x, ball.y, ballRadius, 0, 2 * Math.PI, false);
ctx.fillStyle = "#000";
ctx.fill();
}
}
function createBat() {
// ctx.clearRect(0, 0, width, height)
dx = mouse[0] - point[0],
dy = mouse[1] - point[1];
rot = Math.atan2(dy, dx);
ctx.fillStyle = 'red';
ctx.fillRect(point[0], point[1], 10, 10);
ctx.fillStyle = 'gray';
ctx.save();
ctx.translate(point[0], point[1]);
ctx.rotate(rot);
ctx.fillRect(0, 0, batHeight, batWidth);
ctx.moveTo(point[0], point[1]);
ctx.lineTo(point[0] + (mouse[0] - point[0]) + 0.5, point[1] + (mouse[1] - point[1]) * 0.5);
//ctx.stroke();
ctx.restore();
}
function linePoint(x1, y1, x2, y2, px, py, ball) {
var d1 = dist(px, py, x1, y1);
var d2 = dist(px, py, x2, y2);
var lineLen = dist(x1, y1, x2, y2);
var buffer = 3;
var batAngle = Math.atan2(d2, d1);
var batAngleX = Math.sin(batAngle);
var batAngleY = -Math.cos(batAngle);
if (d1 + d2 >= lineLen - buffer && d1 + d2 <= lineLen + buffer) {
var d = 2 * (ball.velocity.x * batAngleX + ball.velocity.y * batAngleY);
ball.x -= d * batAngleX;
ball.x -= d * batAngleY;
ball.velocity.x -= d * batAngleX + res;
ball.velocity.y -= d * batAngleY + res;
return true;
}
return false;
}
function dist(x1, y1, x2, y2) {
var xs = x2 - x1,
ys = y2 - y1;
xs *= xs;
ys *= ys;
return Math.sqrt(xs + ys);
}
function getRandomNumber(min, max) {
return Math.random() * (max - min) + min;
}
function randomPoint(min, max) {
var rndNum = Math.random() * (max - min) + min;
target = {
x: canvasWidth,
y: rndNum
};
// ctx.beginPath();
// ctx.arc(rndNum, canvasHeight, ballRadius, 0, 2 * Math.PI, false);
// ctx.fillStyle = "#ff0";
// ctx.fill();
}
function isOnCanvas(obj) {
if (obj.x <= mainCanvas.width && obj.y <= mainCanvas.height - bottomRadius) {
return true;
}
return false;
}
function hitGround(obj) {
if (obj.y >= mainCanvas.height - bottomRadius) {
//console.log("hit the ground");
return true;
}
return false;
}
function hitTop(obj) {
if (obj.y <= borderRadius) {
//console.log("hit the top");
return true;
}
return false;
}
function hitLeft(obj) {
if (obj.x <= borderRadius) {
//console.log("hit the left");
return true;
}
return false;
}
function hitRight(obj) {
if (obj.x >= mainCanvas.width - borderRadius) {
//console.log("hit the left");
return true;
}
return false;
}
function drawLineRandomPoint(moveX, moveY, lineX, lineY, strColor) {
ctx.beginPath();
ctx.moveTo(moveX, moveY);
ctx.lineTo(lineX, lineY);
ctx.strokeStyle = strColor;
ctx.stroke();
}
mainCanvas.addEventListener('mousemove', function (e) {
e.time = Date.now();
res = makeVelocityCalculator(e, previousEvent);
previousEvent = e;
mouse[0] = e.clientX;
mouse[1] = e.clientY;
});
function makeVelocityCalculator(e_init, e) {
var x = e_init.clientX, new_x, new_y, new_t,
x_dist, y_dist, interval, velocity,
y = e_init.clientY,
t;
if (e === false) {
return 0;
}
t = e.time;
new_x = e.clientX;
new_y = e.clientY;
new_t = Date.now();
x_dist = new_x - x;
y_dist = new_y - y;
interval = new_t - t;
// update values:
x = new_x;
y = new_y;
velocity = Math.sqrt(x_dist * x_dist + y_dist * y_dist) / interval;
return velocity;
}
mainCanvas.addEventListener('mouseover', function (e) {
animate = true;
executeFrame();
});
mainCanvas.addEventListener("mouseout", function (e) {
animate = false;
});
executeFrame();
window.requestAnimFrame = (function () {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function (callback) {
window.setTimeout(callback, 1000 / 60);
};
})();
<body>
<canvas id="mainCanvas" height="400" width="600"></canvas>
<script src="main.js" type="text/javascript"></script>
</body>

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