So far in the samples of varies box2d js implementation I can find only element defined in shapes (ball/box/etc), is there a way to create an element defined by an image, e.g. a boulder?
You can use the b2PolyDef and b2PolyShape objects to create polygons.
This documentation is meant for AS3 but it is relatively simple to figure out the JavaScript equivalent.
If you wanted to automate the mapping from an image's bounding box to the polygon, you could use canvas and getImageData() to seek through the pixels looking for non transparent (assuming your image has a transparent background). This is probably more effort than it is worth though.
Also see Understanding custom polygons in Box2D.
I was trying to solve a same kind of problem when i came across this brilliant answer. Hope this will help you.
Related
This website has an excellent animated map showing the migration patterns of wildebeest in the Serengeti. Unfortunately, they animated their map using Flash.
I wanted to know whether there were alternatives for doing something similar, perhaps with Javascript. I found a plugin called Two.js however the documentation isn't great and it seems to be a bit overkill for what I need.
Does anyone know of any good resources or examples they could kindly link me to?
I think you have two options:
Using HTML5 canvas and animate your objects using window.requestAnimationFrame();
Animate the dom, here you could use GSAP or Web Animation API.
With HTML5 canvas you work with raster image (pixels) instead using the DOM you could animate any HTML elements including also SVG which is vector.
I am looking to animate an image onto a canvas via a circle 'brush' [Think Photoshop default brush] wherever the circle moves on a path the image is revealed.
The image would be a bitmap, not a vector file.
The brush will not have any additional detail beyond displaying the image its 'painting'
As additional clarification, the circle brush is moving automatically the user does not move the brush. It is just animated along a path.
I am really curious to see how this can be done with Raphael.
Thanks in advance!
If you want to achieve something like that, you better think of using Canvas. Since Raphael is a library oriented exclusively to SVG. You can use non-svg images, but you are going to face lots of limitations.
On the other hand, Canvas is pixel oriented, so what you are trying to do is going to be easier.
Raphael is great when it comes to SVG and user interaction, because the elements you create, are nodes inside the DOM, and you can easily bind them to events.
If you still want to achieve something like that with Raphael, you are going to need to start digging a bit into Raphael's methods. Is to difficult for someone to explain the whole process. You better start trying, and ask some question on more particular problems.
Apart from Raphael's documentation, I recommend this exaggeratedly colorful, but useful site which have some working examples.
Either way I think you should reconsider using Raphale over Canvas!
I hope that helps!!
Hi I'm looking for a way to create a panorama view with a 360 degrees photo. I need a solution to do create something like QTVR. There is a lot flash based software out there (I'm trying to avoid that) and also some javascript/prototype/jquery solutions. But none of the solutions I've found have the behaviour I'm looking for. I want to eanable users to look around (just horizontal). Furniture objects on the pictures should react on mouseover, so that I might have multiple "layers" to distort. Is there a way to manipulate images in pure javascript or with jquery so, that it looks like they where bent cylindrical? Or does anyone know good libraries that support that kind of image manipulation? Might webgl be a good solution? I don't really know how to start. Is there anyone who could give me a hint. I'm just looking for a direction. google didn't bring me usable results.
Check out three.js
http://mrdoob.github.com/three.js/examples/webgl_panorama_equirectangular.html
Also, you could possibly do some of the image manipulation via canvas.
https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API/Tutorial/Pixel_manipulation_with_canvas
It might be easier (with canvas) to just have a fully processed panoramic image, and figure out which pixels represent your interactive object. Then listen for mouseovers on those pixels.
try out http://panorado.com/en/PanoradoJs.php
There you'll find an excellent HTML5/JS based Viewer.
There are lots of tool to do that. Have you tried www.vtility.net ? Im not sure if it had mouse over layering. But it was the only SEO friendly that I have found.
I want to write some animation with html5 canvas element. I found that there are some js libraries that help to leverage canvas functionality. For example KineticJS, FabricJS. But I don't know which library to use.
What is pros and cons when using this libraries? Or may be you know even better implementation?
edit
I'm going to create something similar to static picture, but with piece оf animation. For example floating clouds on the sky, flower where you can tear off a petal and throw it. May be some animation with sun. This is general description, hope this helps.
There is Processing.js, which is a port of Processing for Java. Processing.js is ideal for 2d images.
Raphaël uses svg to draw images, which results in more compatibility.
For 3d there is Three.js, which uses both canvas and webgl.
There are a lot of different libraries around, you should first find out what you want to draw.
http://javascript.open-libraries.com/utilities/drawing/10-best-javascript-drawing-and-canvas-libraries/
cgSceneGraph is a javascript animation framework providing a full animation engine with timelines, animation keys, ...
It also provides helper methods to easily add animations on every attribute of an element.
The example on the home page of the website is exactly what you talk about, so it should fit your need :)
For simple animations forget the canvas and use position: absolute div elements with background image that you can move around with CSS transform translate3d and scale3d.
I'd like to be able to write an application in HTML5 that is similar to the following.
HTML5 Canvas Animals on the Beach Game with KineticJS
The problem with that demo though is the mouse over event is only accurate to the rectangle surrounding the animal. Is there any way to do this with more accuracy, be it in KinectJS or otherwise?
There are generally two ways:
Using custom paths with each image as hitboxes (that you manually define) then using an is-point-in-path algorithm
Using a ghost-canvas (or whatever you like to call it) as I detailed in this old tutorial. Ignore the link to the new tutorial, the old one uses what you'd want.
The first method here is much faster but requires a lot more code and manual work. The second method is pixel-perfect but much slower. Still, if you don't have an enormous amount of objects it may suit your needs.