glsl

I'm rendering circles using regl, and have three goals: The canvas should be transparent, showing HTML content behind it. Circles should be antialiased smoothly. Overlapping circles should look reasonable (blend colors, no corners showing) So far, I have this: Glitch code and demo . UPDATE: The demo links now reflect the working, accepted answer. Code below is unchanged. index.js const regl = require('regl'); const glsl = require('glslify'); const vertexShader = glsl.file('../shaders/vertex.glsl'); const fragmentShader = glsl.file('../shaders/fragment.glsl'); // Create webgl context and clear.

First - Does subroutines require GLSL 4.0+? So it unavailable in GLSL version of OpenGL ES 2.0? I quite understand what multi-pass shaders are. Well what is my picture: Draw group of something (e.g. sprites) to FBO using some shader. Think of FBO as big texture for big screen sized quad and use another shader, which, for example, turn texture colors to grayscale. Draw FBO textured quad to screen with grayscaled colors. Or is this called else? So multi-pass = use another shader output to another shader input? So we render one object twice or more? How shader output get to another shader input?

I'm curious about the *BlockBinding argument used in several of OpenGLs buffer object related functions. For example the uniformBlockBinding parameter in glUniformBlockBinding , storageBlockBinding​ in glShaderStorageBlockBinding , and the corresponding index parameter in glBindBufferRange and glBindBufferBase . I know that calls to glUniformBlockBinding and glShaderStorageBlockBinding aren't necessary if binding points are set in the shaders using layout qualifiers such as: layout (binding = 0) blockName {...} and from testing around on my machine I've noticed three things: 1) setting binding

I have a scene with several models with individual positions and rotations. Given normals, the shaders apply simple bidirectional lighting to each pixel. That is my vertex shader. #version 150 in vec3 position; in vec3 normal; in vec2 texcoord; out vec3 f_normal; out vec2 f_texcoord; uniform mat4 model; uniform mat4 view; uniform mat4 proj; void main() { mat4 mvp = proj * view * model; f_normal = normal; f_texcoord = texcoord; gl_Position = mvp * vec4(position, 1.0); } And here is the fragment shader. #version 150 in vec3 f_normal; in vec2 f_texcoord; uniform sampler2D tex; vec3 sun = vec3(0.5

I'm working on a project that uses OpenGL 4.0 shaders. I have to supply the call to glShaderSource() with an array of char arrays, which represents the source of the shader. The shader compilation is failing, with the following errors: (0) : error C0206: invalid token "<null atom>" in version line (0) : error C0000: syntax error, unexpected $end at token "<EOF>" Here's my (hello world) shader - straight from OpenGL 4.0 shading language cookbook #version 400 in vec3 VertexPosition; in vec3 VertexColor; out vec3 Color; void main() { Color = VertexColor; gl_Position = vec4( VertexColor, 1.0 ); }

Is there a way to access the shaders attached to a program? That is, given a program, can I do something like: vertexShader = getVertexShaderFromProgram(program); (I would like to log shader compilation status within my function that validates my program, but I only keep a reference to the program, not the shaders.) glGetAttachedShaders() to get the names of the shaders attached to the given program object. glGetShaderiv( ..., GL_SHADER_TYPE, ... ) to get the type (vertex, geometry, fragment) of shader. glGetShaderiv( ..., GL_SHADER_SOURCE_LENGTH, ... ) on each shader name to figure out how