Globalcomposite are available in html5 canvas. Is it available in threejs? How to implement the destination out composite operation in three.js?
Thank you.
If you are using three.js ' CanvasRenderers you can use globalCompositeOperation as they are for 2d contexts.
If you are using a webgl context, basically everything is possible with shaders. As Shiladittya's comment states, three.js also provides blending modes (see this example). They are available in the material property blending.
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I'm new to three js but i have managed to make polyhedron with one texture. but with multiple and with caption is somewhat advanced
Applying multiple diffuse textures in three.js requires the usage of multiple materials. THREE.DodecahedronGeometry as well as all other geometry classes derived from THREE.PolyhedronGeometry do no support multiple materials.
If you still want to use such a geometry with multiple materials, you need to define so called group data. But since you are a beginner in three.js, it might be easier to create your mesh in a DCC tool like Blender, export it to glTF and then import it into your application via THREE.GLTFLoader.
three.js R107
I'd like to have a dynamic GLSL shader texture to be used as a reference map (for displacement and other stuff) on multiple, different materials on different Meshes.
My approach would be to do the computation one time, using a THREE.WebGLRenderTarget, setup a ortho cam, a 1X1 plane with a THREE.ShaderMaterial, and access the WebGLRenderTarget.texture, that I'd embed in a "master" object, whenever and wherever I need.
Is there any "official" object I can / may use for this? I seen the postprocessing objects are pretty similar (EG ShaderPass) but I'm unsure if and how to use them.
Thank you.
How do I create a three.js material/geometry which uses part of a texture?
I am first rendering a scene to a texture. This texture is used for a Mesh with a CubeGeometry and a MeshLambertMaterial. What I would like to do now is have only a part of the texture displayed on the cube face (like a window into the texture).
I've done this before using OpenGL ES directly, with shaders, but I don't see what parameters might make it possible using the standard three.js library.
That is what texture coordinates are for. See this question and answer:
http://stackoverflow.com/questions/19366991/drawing-part-of-open-gl-texture/19367844#19367844
Coming from ActionScript + Papervision I am familiar with "AS3DMod" a library that modifies 3D meshes to bend, twist,etc. Now I am working with THREE.js and found this:"#MOD3 As3dMod 3D Modifier Library port for Javascript and Three.js, Pre3d and J3D and Copperlicht" but the code is outmoded for any remotely current versions of THREE.js (and also is written for canvas rendering, NOT webGL). The creator has not been able to update. Does anyone know of any similar 3D libs that can "bend ,twist, bloat" 3D meshes in webGL? I am not sufficiently skilled to update this myself.
Thanks for any suggestions.
Not that I know of, but depending on what modifiers you are utilize, it may not be too difficult to write a modifier yourself. Typically you can reuse the logic in js for Canvas renderer, and as for WebGLRenderer, you can implement it in the Vertex shaders.
I'm struggling with a visualization I'm working on that involves a stream of repeated images. I have it working with a single sprite with a ParticleSystem, but I can only apply a single material to the system. Since I want to choose between textures I tried creating a pool of Particle objects so that I could choose the materials individually, but I can't get an individual Particle to show up with the WebGL renderer.
This is my first foray into WebGL/Three.js, so I'm probably doing something bone-headed, but I thought it would be worth asking what the proper way to go about this is. I'm seeing three possibilities:
I'm using Particle wrong (initializing with a mapped material, adding to the scene, setting position) and I need to fix what I'm doing.
I need a ParticleSystem for each sprite I want to display.
What I'm doing doesn't fit into particles at all and I really should be using another object type.
All the examples I see using the canvas renderer use Particle directly, but I can't find an example using the WebGL renderer that doesn't use ParticleSystem. Any hints?
Ok, I am going from what I have read elsewhere on this github issues page. You should start by reading it. It seems that the Particle is simply for the Canvas Renderer, and it will become Sprite in a further edition of Three.JS. ParticleSystem, however is not going to fulfill your needs either it seems. I don't think these classes are going to help you accomplish this in WebGL in 3D. Depending on what you are doing you might be better off with the CanvasRenderer anyway. ParticleSystem will only allow you to apply a single material which will serve as the material for each particle in the system as you suggested.
Short answer:
You can render THREE.Particle using THREE.CanvasRenderer only.