glsl

问题 I'm looking at this example: http://threejs.org/examples/webgl_custom_attributes.html and notice that the custom displacement attribute gets filled by vertices.length for ( var v = 0; v < vertices.length; v++ ) { values[ v ] = 0; noise[ v ] = Math.random() * 5; } My question is, how does this relate to the number of normals, uvs and tangents? When i export my model from 3ds max, i have more UVs than vertices. I need to assign tangents per this UV number because they are different at seams. I

问题 i have issues reconstructing world positions from previously stored linear depth in glsl. I read lots of info online, but can't find my problem... So this is what I got: VS (storing depth to 32F): float linDepth(float z) { return (-z-zNear)/(zFar-zNear); } void main() { vec4 position = uViewMatrix * uModelMatrix * vec4(aPosition, 1); depth = linDepth(position.z); //store linear view-depth } FS (reconstuction): void main() { vec3 vUV = vec2(0..1, 0..1); (from screen aligned quad) vec3 ndc =

问题 I've read all recommended posts, I've tried those solutions, but non of them helped. In short problem lies in the third argument of glShaderSource(vertexShader, 1, &vertexShaderSource, NULL); This code work: const char *vertexShaderSource = "#version 120 \n" "attribute vec3 pos;\n" "attribute vec2 texCoord;\n" "varying vec2 texCoord0;\n" "uniform mat4 transform;\n" "void main()\n" "{\n" " gl_Position = transform * vec4(pos, 1.0);\n" " texCoord0 = texCoord;\n" "}\0"; But I want to read it from

问题 I have a C++ class Matrix4x4 which has an array of 16 floats and no virtual methods: class Matrix4x4 { public: float values[16]; Matrix4x4(); Matrix4x4(float v0, float v1, float v2, float v3, float v4, float v5, float v6, float v7, float v8, float v9, float v10, float v11, float v12, float v13, float v14, float v15); Matrix4x4(const Quaternion &quat, const Vector3 &pos); void convertToQuatPos(Quaternion &quat, Vector3 &pos); void loadIdentity(); void setValues(float v0, float v1, float v2,

问题 I'm trying to write a blur filter in GLSL ES 2.0 and I'm getting an Error with the line assigning gl_FragColor. I've not been able to figure out why #extension GL_OES_EGL_image_external : require precision mediump float; varying vec2 textureCoordinate; uniform samplerExternalOES s_texture; void main() { float gaus[25] = float[25](0.01739, 0.03478, 0.04347, 0.03478, 0.01739, 0.03478, 0.07282, 0.10434, 0.07282, 0.03478, 0.04347, 0.10434, 0.13043, 0.10434, 0.04347, 0.03478, 0.07282, 0.10434, 0

问题 Before I used a samplerCube to render the cube This is my previous fragmentShader code "uniform samplerCube tCubeTgt;", "varying vec3 posTgt;", "void main() {", "vec4 reflectedColorTgt = textureCube( tCubeTgt, vec3( -posTgt.x, posTgt.yz ) );", "gl_FragColor = reflectedColorTgt ;", "}" Now I want to use 6 sampler2D to render a cube. what should I do 回答1: Why? In any case looking up how cube mapping works there's a function and table in the OpenGL ES 2.0 spec showing how cube mapping works

问题 I'm trying to draw a sphere with just a diffuse color, but nothing shows up. All the OpenGL code should be correct, because if I swap the "color" shader with "textured" shader, everything shows up nicely. This is the shader selection code. The if-branch is for the textured objects, and the else-branch is for color-only objects. GL.Disable(EnableCap.Blend); if (phong.diffuseTexture != 0) { texturedShader.Enable(); GL.UniformMatrix4(texturedShader.GetUniformLocation("view"), false, ref camView)

问题 EDIT I've read all recommended posts, I've tried those solutions, but non of them helped. In short problem lies in the third argument of glShaderSource(vertexShader, 1, &vertexShaderSource, NULL); This code work: const char *vertexShaderSource = "#version 120 \n" "attribute vec3 pos;\n" "attribute vec2 texCoord;\n" "varying vec2 texCoord0;\n" "uniform mat4 transform;\n" "void main()\n" "{\n" " gl_Position = transform * vec4(pos, 1.0);\n" " texCoord0 = texCoord;\n" "}\0"; But I want to read it

问题 I have a vertex shader as such void main (){ vec4 wPos = modelMatrix * vec4( position , 1. ); vWorldPosition = wPos.xyz; float mask = step( 0., dot( cameraDir, normalize(normalMatrix * aNormal) ) ); gl_PointSize = mask * uPointSize; gl_Position = projectionMatrix * viewMatrix * wPos; } I'm not entirely sure how to test the performance of the shader, and exclude other factors like overdraw. I imagine a point of size 1, arranged in a grid in screen space without any overlap would work?

问题 I'm new to OpenGL and GLSL Programming. Recently I need to do freehand masking on an image like below Image. How could I achieve this using Fragment Shader? Currently, I am trying this with below fragment shader but Nothing Change on Image. precision mediump float; varying vec2 v_TexCoordinate; varying vec2 v_TexCoordinate2; uniform sampler2D u_Texture; uniform sampler2D u_Texture2; uniform bool u_alpha_test_enable; void main() { float mask = texture2D(u_Texture, v_TexCoordinate).a; // if (u