shader

I'm working on creating a shader to generate terrain with shadows. My starting point is to clone the lambert shader and use a ShaderMaterial to eventually customise it with my own script. The standard method works well: var material = new MeshLambertMaterial({map:THREE.ImageUtils.loadTexture('images/texture.jpg')}); var mesh = new THREE.Mesh(geometry, material); etc The result: However I'd like to use the lambert material as a base and work on top of it, so I tried this: var lambertShader = THREE.ShaderLib['lambert']; var uniforms = THREE.UniformsUtils.clone(lambertShader.uniforms); var

I need to implement a custom shader node using SpriteKit. In simulator everything is ok. On a device (iPad 3rd gen) shader animation is smooth just for first ~30 seconds, after that shader's fps are gradually falling down until it looks like a slideshow (1 fps or even less) It is worth noting, that SpriteKit shows 60 fps, so does Xcode. CPU is ~75% busy, but shader itself shows ~1fps. I own only 3rd generation iPad and I currently don't have an opportunity to test it on other devices Shader code is taken from wwdc session, but the issue is reproduced with any animated shaders I've tried.

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I want to have two light sources: a directional one and a spotlight. I cannot seem to get what I am doing wrong -- probably not understanding how shaders work! I get the first light fine but no sign of the effects of the second one (aka spotlight). Here is the fragement shader that I came up with: varying vec4 diffuse,ambientGlobal, ambient; varying vec3 normal,lightDir,halfVector; varying float dist; void main() { vec3 n, halfV, viewV, ldir; float NdotL, NdotHV; vec4 color = ambientGlobal; float att, spotEffect; n = normalize(normal); NdotL

I am writing a shader according to the Phong Model . I am trying to implement this equation: where n is the normal, l is direction to light, v is the direction to the camera, and r is the light reflection. The equations are described in more detail in the Wikipedia article. As of right now, I am only testing on directional light sources so there is no r^2 falloff. The ambient term is added outside the below function and it works well. The function maxDot3 returns 0 if the dot product is negative, as it usually done in the Phong model. Here's my code implementing the above equation: #include

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: I am trying to learn OpenGL and following this: http://www.opengl-tutorial.org/beginners-tutorials/tutorial-3-matrices/ Up until the point where they started passing matrices to the vertex shader to translate the triangle they where drawing I was following along. This is the shader program where it starts to go wrong: #version 330 core layout ( location = 0 ) in vec3 vertexPosition_modelspace ; uniform mat4 MVP ; void main (){ vec4 v = vec4 ( vertexPosition_modelspace , 1 ); // Transform an homogeneous 4D vector gl_Position = MVP *

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have a problem with the glsl's version on my mac os X 10.9.2. I'm making a program in c++ with OpenGL and SDL2 I can't upgrade from my version 120 to any version higher. How I can upgrade please ? I compile like this : g++ and my flag is : -framework SDL2 -lSDLmain -framework OpenGL -framework SDL2_image -framework cocoa ERROR: 0:3: '' : version '330' is not supported 回答1: On OS/X 10.9 to create an OpenGL 3.3/4.1 context you need to add the following snippet before SDL_CreateWindow . A full example is available here: https://gist.github

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: So to implement a tilemap using Threejs and Brandon Jone's tilemap method ( found here ) I am using a THREE.Plane geometry for each layer, and painting the face with the following custom shaders: Vertex Shader: var tilemapVS = [ "varying vec2 pixelCoord;", "varying vec2 texCoord;", "uniform vec2 mapSize;", "uniform vec2 inverseTileTextureSize;", "uniform float inverseTileSize;", "void main(void) {", " pixelCoord = (uv * mapSize);", " texCoord = pixelCoord * inverseTileTextureSize * inverseTileSize;", " gl_Position = projectionMatrix *

https://www.cnblogs.com/fuckgiser/p/5975274.html 在介绍Renderer的第一篇，我就提到WebGL1.0对应的是OpenGL ES2.0，也就是可编程渲染管线。之所以单独强调这一点，算是为本篇埋下一个伏笔。通过前两篇，我们介绍了VBO和Texture两个比较核心的WebGL概念。假设生产一辆汽车，VBO就相当于这个车的骨架，纹理相当这个车漆，但有了骨架和车漆还不够，还需要一台机器人来加工，最终才能成产出这辆汽车。而Shader模块就是负责这个生产的过程，加工参数（VBO，Texture），执行渲染任务。 这里假设大家对Shader有一个基本的了解，这一块内容也很多，不可能简单两句轻描淡写就豁然开朗，而且我也没有进行过系统的学习，所以就不班门弄斧了。进入主题，来看看Cesium对Shader的封装。 图1：ES2.0可编程渲染管线 上图是可编程渲染管线的一个大概流程，我们关注的两个橙色的圆角矩形部分，分别是顶点着色器和片源着色器。既然是可编程渲染管线，面向Shader的开发者提供了一种称为GLSL的语言，如果你懂C的话，两者语法是相当的，所以从语法层面学习成本不大。 ShaderSource创建 首先，Cesium提供了ShaderSource类来加载GLSL代码，我们来看一下它对应的拷贝构造函数： ShaderSource