My I am trying to do a click to zoom feature with Three.js, I have a canvas and an object loaded in the canvas.On click I am trying to place the camera near the point of intersection(Actually like zooming that point).
Here is what I have done, but doesn't work as I wanted, on click camera positions changes but kind of works partially sometimes camera is placed near the point of intersection, some times not.
onmousedown = function (event) {
var raycaster = new THREE.Raycaster();
var mouse = new THREE.Vector2();
event.preventDefault();
mouse.x = (event.clientX / self.renderer.domElement.clientWidth) * 2 - 1;
mouse.y = -(event.clientY / self.renderer.domElement.clientHeight) * 2 + 1;
raycaster.setFromCamera(mouse, self.camera);
var objects = [];
for (var i = 0; i < self.scene.children.length; i++) {
if (self.scene.children[i] instanceof THREE.Group) {
objects.push(self.scene.children[i]);
}
}
console.log(objects);
var intersects = raycaster.intersectObjects( objects,true );
console.log(intersects.length);
if (intersects.length > 0) {
self.camera.up = new THREE.Vector3(0, 0, 1);
self.camera.lookAt(new THREE.Vector3(0, 0, 0));
self.camera.position.z = intersects[0].point.z * .9;
self.camera.position.x = intersects[0].point.x * .9;
self.camera.position.y = intersects[0].point.y * .9;
}
};
Here self is a global viewer object which holds camera, canvas, different objects etc.
0.9 is just a number used to place camera just near the point of intersection.
camera used is PerspectiveCamera and controls is TrackballControls
new THREE.PerspectiveCamera(90, this.width / this.height, 1, 1000);
The objects loaded are from .obj or .dae files ,I expect this to work like click on any point on the object and place the camera near that point. But camera is moving but sometimes not near the point I clicked.
Does intersects[0] gives the nearest intersection point? or nearest in the direction of camera ?
What is my mistake here ?
I am new to three js , just started learning it.If something or some logic is wrong help me with that.
The position is a bit complicated to calculate; you have to find the segment between camera and intersection and than place the camera at specific distance from intersection along the segment looking to the intersection point.
try this:
var length=[the desiderated distance camera-intersection]
var dir = camera.position.clone().sub(intersects[0].point).normalize().multiplyScalar(length);
camera.position = intersects[0].point.clone().add(dir);
camera.lookAt(intersects[0].point);
I have created a fiddle: http://jsfiddle.net/h5my29aL/
It's not so difficult. Think of your object as a planet, and your camera as a satellite. You need to position the camera somewhere in an orbit near your object. Three contains a distanceTo function that makes it simple. The example uses a sphere, but it will work with an arbitrary mesh. It measures the distance from the center point to the desired vector3. In your case the vector3 is likely the face position returned by a picker ray. But anyhow, the lookAt is set to the mesh, and then a distance from the vertex is calculated so that the camera is always the same altitude regardless of a vertex's or face's distance from the object center.
var point = THREE.GeometryUtils.randomPointsInGeometry( geometry, 1 );
var altitude = 100;
var rad = mesh.position.distanceTo( point[0] );
var coeff = 1+ altitude/rad;
camera.position.x = point[0].x * coeff;
camera.position.y = point[0].y * coeff;
camera.position.z = point[0].z * coeff;
camera.lookAt(mesh.position);
I've came somewhat close to what I want with an example from Three js.
Three JS webgl_decals
this is what I have done.
function zoomCam(event) {
var point_mouse = new THREE.Vector2(),
var point_x = null;
var point_y = null;
if (event.changedTouches) {
point_x = event.changedTouches[ 0 ].pageX;
point_y = event.changedTouches[ 0 ].pageY;
} else {
point_x = event.clientX;
point_y = event.clientY;
}
point_mouse.x = (point_x / window.innerWidth) * 2 - 1;
point_mouse.y = -(point_y / window.innerHeight) * 2 + 1;
if (sceneObjects.length > 0) {
var raycaster = new THREE.Raycaster();
raycaster.setFromCamera(point_mouse, camera);
var intersects = raycaster.intersectObjects(sceneObjects, true);
if (intersects.length > 0) {
var p = intersects[ 0 ].point;
var n = intersects[ 0 ].face.normal.clone();
n.multiplyScalar(10);
n.add(intersects[ 0 ].point);
camera.position.copy(n);
camera.lookAt(p);
}
}
There might be some minor issues as I formatted/changed the code for answering here. Check the code before implementing.
Related
I'm making a 2D scatterplot with a tooltip, and currently the raycaster to detect when a point is being hovered over is broken. The tooltip only activates when touching an object, which is correct behavior, but it shows completely random data from points that aren't even close on the x/y plane, and changes information even when there are no other points close to the one being hovered over. Can anyone help me debug this behavior? Here is some relevant code (the rest can be found in the link above):
...loading in points (stored in data_points array), creating scene, etc.
raycaster = new THREE.Raycaster();
raycaster.params.Mesh.threshold = 20;
view.on("mousemove", () => {
let [mouseX, mouseY] = d3.mouse(view.node());
let mouse_position = [mouseX, mouseY];
checkIntersects(mouse_position);
});
function mouseToThree(mouseX, mouseY) {
return new THREE.Vector3(
mouseX / viz_width * 2 - 1,
-(mouseY / height) * 2 + 1,
1
);
}
function checkIntersects(mouse_position) {
let mouse_vector = mouseToThree(...mouse_position);
raycaster.setFromCamera(mouse_vector, camera);
let intersects = raycaster.intersectObjects(scene.children, true);
if (intersects[0]) {
let sorted_intersects = sortIntersectsByDistanceToRay(intersects);
let intersect = sorted_intersects[0];
let index = intersect.faceIndex;
let datum = data_points[index];
showTooltip(mouse_position, datum);
} else {
hideTooltip();
}
}
function sortIntersectsByDistanceToRay(intersects) {
return _.sortBy(intersects, "distanceToRay");
}
...tooltip functions, details
Any help would be greatly appreciated. Thank you!
Why are you using d3.mouse(view.node()); to get the mouse position? It looks like that's giving you wild results. When moving the pointer in a tiny space, I get an X range from 2200 to -97, when it should be a few pixels apart.
I recommend that on mousemove you get the exact XY screen position by using the default JavaScript method of event.clientX and event.clientY
See this example, taken directly from a Three.js Raycasting example
function onMouseMove( event ) {
mouse.x = ( event.clientX / renderer.domElement.clientWidth ) * 2 - 1;
mouse.y = - ( event.clientY / renderer.domElement.clientHeight ) * 2 + 1;
raycaster.setFromCamera( mouse, camera );
}
Also, I recommend removing document margins via CSS so your measurements aren't off by a few pixels.
Figured out the answer. There was not a proper "index" variable for my datapoints (THREE.Group consisting of [THREE.Mesh, THREE.LineLoop]), which is why the raycasting worked but not point selection (DON'T use faceIndex). So I created one under the userData field of the mesh.
// Create circle geometries
for (var i=0; i<data_points.length; i++) {
// Circle
let geo = new THREE.CircleBufferGeometry(data_points[i].radius, 32);
let mat = new THREE.MeshBasicMaterial( {color: color_array[data_points[i].label] } );
let mesh = new THREE.Mesh(geo, mat);
mesh.userData.id = i;
...lineLoop and Group code
}
...more code
function onMouseMove(event) {
mouseRay.x = ( event.clientX / renderer.domElement.clientWidth ) * 2 - 1;
mouseRay.y = - ( event.clientY / renderer.domElement.clientHeight ) * 2 + 1;
mouseRay.z = 1;
let mouse = [event.clientX, event.clientY];
raycaster.setFromCamera(mouseRay, camera);
let intersects = raycaster.intersectObjects(scene.children, true);
if (intersects[0]) {
let sorted_intersects = sortIntersectsByDistanceToRay(intersects);
console.log(sorted_intersects);
let intersect = sorted_intersects[0];
// Here is the change I made!!!
let index = intersect.object.userData.id;
let datum = data_points[index];
highlightPoint(datum);
showTooltip(mouse, datum);
} else {
removeHighlights();
hideTooltip();
}
}
I've looked at this question:
Mouse / Canvas X, Y to Three.js World X, Y, Z
and have implemented it in my code, the problem is that I can't seem to get it to work as others have stated.
I need to place an object in front of the camera via X and Y screen coords, not necessarily from the mouse.
This object will be at a specified distance in front of the camera, either from a pre-defined maximum distance or a calculated object distance.
Note: My Camera can be at any position in my scene and facing any direction
Here is my code:
this.reticlePos.x = 500;
this.reticlePos.y = 300;
this.reticlePos.z = 0.5;
this.projector.unprojectVector(this.reticlePos, this.camera);
//check for collisions, if collisions set distance to collision distance
var distance = this.RETICLE_RADIUS;
var direction = new THREE.Vector3( 0, 0, -1 );
direction.applyQuaternion( this.camera.quaternion );
this.rayCaster.set(this.camera.position, direction);
var collisionResults = this.rayCaster.intersectObjects(this.sceneController.obstacles);
if( collisionResults.length !== 0 ) {
// console.log('Ray collides with mesh. Distance :' + collisionResults[0].distance);
distance = collisionResults[0].distance - 20;
}
// set the reticle position
var dir = this.reticlePos.clone().sub( this.camera.position ).normalize();
var pos = this.camera.position.clone().add( dir.multiplyScalar( distance ) );
this.reticleMesh.position.copy( pos );
As you can see is is very similar to the linked question, yet I cannot see the object in front of my camera.
Any insight into this would be greatly appreciated.
I figured out the answer myself for anyone that checks this question later on.
To get my screen coordinates I needed to convert some input data from a gyroscope, and didn't realize that I still needed to do the following to my calculated screen coordinates:
this.reticlePos.x = ( this.reticlePos.x / window.innerWidth ) * 2 - 1;
this.reticlePos.y = - ( this.reticlePos.y / window.innerHeight ) * 2 + 1;
After doing this, everything works as expected.
I'm looking to understand quaternions for three.js, but for all the tutorials, I haven't been able to translate them into the application I need. This is the problem:
Given a sphere centered at (0,0,0), I want to angle an object on the sphere's surface, that acts as the focal point for the camera. This point is to be moved and rotated on the surface with keyboard input.
Setting the focal point into a chosen orbit is easy of course, but maintaining the right rotation perpendicular to the surface escapes me. I know quaternions are neccessary for smooth movement and arbitrary axis rotation, but I don't know where to start.
The second part then is rotating the camera offset with the focal point. The snippet I found for this does not have the desired effect anymore, as the cameraOffset does not inherit the rotation:
var cameraOffset = relativeCameraOffset.clone().applyMatrix4( focalPoint.matrixWorld );
camera.position.copy( focalPoint.position.clone().add(cameraOffset) );
camera.lookAt( focalPoint.position );
Update 1: Tried it with fixed camera on the pole and rotating the planet. But unless I'm missing something important, this fails as well, due to the directions getting skewed completely when going towards the equator. (Left becomes forward). Code in update is:
acceleration.set(0,0,0);
if (keyboard.pressed("w")) acceleration.x = 1 * accelerationSpeed;
if (keyboard.pressed("s")) acceleration.x = -1 * accelerationSpeed;
if (keyboard.pressed("a")) acceleration.z = 1 * accelerationSpeed;
if (keyboard.pressed("d")) acceleration.z = -1 * accelerationSpeed;
if (keyboard.pressed("q")) acceleration.y = 1 * accelerationSpeed;
if (keyboard.pressed("e")) acceleration.y = -1 * accelerationSpeed;
velocity.add(acceleration);
velocity.multiplyScalar(dropOff);
velocity.max(minV);
velocity.min(maxV);
planet.mesh.rotation.x += velocity.x;
planet.mesh.rotation.y += velocity.y;
planet.mesh.rotation.z += velocity.z;
So I'm still open for suggestions.
Finally found the solution from a mixture of matrices and quaternions:
//Setup
var ux = new THREE.Vector3(1,0,0);
var uy = new THREE.Vector3(0,1,0);
var uz = new THREE.Vector3(0,0,1);
var direction = ux.clone();
var m4 = new THREE.Matrix4();
var dq = new THREE.Quaternion(); //direction quad base
var dqq; //final direction quad
var dq2 = new THREE.Quaternion();
dq2.setFromAxisAngle(uz,Math.PI/2); //direction perpendicular rot
//Update
if (velocity.length() < 0.1) return;
if (velocity.x) { focalPoint.translateY( velocity.x ); }
if (velocity.y) { focalPoint.translateX( velocity.y ); }
//create new direction from focalPoint quat, but perpendicular
dqq = dq.clone().multiply(focalPoint.quaternion).multiply(dq2);
velocity.multiplyScalar(dropOff);
//forward direction vector
direction = ux.clone().applyQuaternion(dqq).normalize();
//use Matrix4.lookAt to align focalPoint with the direction
m4.lookAt(focalPoint.position, planet.mesh.position, direction);
focalPoint.quaternion.setFromRotationMatrix(m4);
var cameraOffset = relativeCameraOffset.clone();
cameraOffset.z = cameraDistance;
cameraOffset.applyQuaternion(focalPoint.quaternion);
camera.position = focalPoint.position.clone().add(cameraOffset) ;
//use direction for camera rotation as well
camera.up = direction;
camera.lookAt( focalPoint.position );
This is the hard core of it. It pans (and with some extension rotates) around the planet without the poles being an issue.
I'm not sure to understand your problem.
But for help, I draw a boat on a sphere with the code below.
var geometry = new THREE.ShapeGeometry(shape);
var translation = new THREE.Matrix4().makeTranslation(boat.position.x, boat.position.y, boat.position.z);
var rotationZ = new THREE.Matrix4().makeRotationZ(-THREE.Math.degToRad(boat.cap));
var rotationX = new THREE.Matrix4().makeRotationX(-THREE.Math.degToRad(boat.latitude));
var rotationY = new THREE.Matrix4().makeRotationY(Math.PI / 2 + THREE.Math.degToRad(boat.longitude));
var roationXY = rotationY.multiply(rotationX);
geometry.applyMatrix(rotationZ);
geometry.applyMatrix(roationXY );
geometry.applyMatrix(translation);
First, I apply a rotation on Z to define boat cap
Then, I apply
rotation on Y,X to to set the boat perpendicular to the surface of
the sphere
Finally I apply a translation to put the boat on the
surafce of the sphere
The rotations order is important
I'm trying to scale height(y) of a cube as well as raising its y position simultaneously so that its base remains on the same x-z plane even after scaling. The rendering works fine but it is not working as expected. The object position increases rapidly in Y and then it starts disappearing. Can anyone help me out?
I've added an eventListener: mouseMove and its listener function to do the above transformations:
var fHeight = 5, yShift;
function onDocumentMouseMove(event) {
var mouseVector = new THREE.Vector3(2*(event.clientX/window.innerWidth) - 1, 1 - 2*(event.clientY/window.innerHeight));
var projector = new THREE.Projector();
var raycaster = projector.pickingRay(mouseVector.clone(), camera);
var intersects = raycaster.intersectObjects( Object.children );
if(intersects.length > 0) {
intersects[0].object.scale.y += 0.1;
fHeight = fHeight*intersects[0].object.scale.y;
yShift = fHeight/2 - intersects[0].object.position.y - 2.5;
intersects[0].object.position.y = intersects[0].object.position.y + yShift;
}
}
You can place the vertices of your cube so its base sticks to its y=0 plane.
Then object.scale.y will directly modify the cube height only, without displacing the base, and you will not have to reposition the object.
Hope it helps
I'm trying to find the ray collision coordinate relative to the face targeted...
code:
var fMouseX = (iX / oCanvas.width) * 2 - 1;
var fMouseY = -(iY / oCanvas.height) * 2 + 1;
//I Use OrthographicCamera
var vecOrigin = new THREE.Vector3( fMouseX, fMouseY, - 1 );
var vecTarget = new THREE.Vector3( fMouseX, fMouseY, 1 );
oProjector.unprojectVector( vecOrigin, this.__oCamera );
oProjector.unprojectVector( vecTarget, this.__oCamera );
vecTarget.subSelf( vecOrigin ).normalize();
var oRay = new THREE.Ray(vecOrigin, vecTarget);
intersects = oRay.intersectObjects([ oCylinderMesh ]);
With intersects[ 0 ].point, I can have the mouse position in 'screen coordinate', but how can I have it in Cylinder coordinate ?
PS: mesh are not rotate, but camera can change position...
Really nice framework ;)
Here is my solution, just get the Cylinder absolute coordinate (position relative to screen), then, itersects[0].point sub the Cylinder absolute coordinate.
The following code may help:
var relativeTo = function(element, ancestor) {
var offset = element.position.clone();
if (element.parent == ancestor) {
return offset;
}
return offset.addSelf(relativeTo(element.parent, ancestor));
}