
Category Archives: OpenGL
(Demo) Fire Shader
(Demo) Heightmap Normal Computing
(Shadertoy to GeeXLab) Heeelix
Smoothstep-based Vertical Image Separator in GLSL
GeeXLab 0.15.0.1 and Two Sided Lighting
How to Check the Availability of an OpenGL Extension

It may be useful to know if the current OpenGL implementation supports a particular OpenGL extension. For example you have coded a cool OpenGL 4.0 demo based on tessellation shaders. It would be nice to display a different scene (actually an error scene) if the demo runs on a system that is limited to OpenGL 3.0.
How to Check OpenGL Errors

I didn’t checked all possible use cases of GLSL Hacker (a huge and actually impossible task) and some sequences of drawing instructions (render calls) can generate OpenGL errors. So if you suspect something dodgy because the rendering is not what you expect, you can check the OpenGL errors after some particular instructions.
GLSL Uniform Structures

Do you know that you can use data structures as uniform variables in GLSL?
GL-Z 0.1.0: Some Coding Details

GL-Z has just been released on Geeks3D’s main blog. It’s a simple OpenGL tool that displays GL_VERSION, GL_RENDERER as well as extensions list.
How To Pass Variables to a GPU Program

In this article, we saw how to use a GPU program with GLSL Hacker. Now we’re going to see how we can pass information (variables) to a GPU program.
Polygon Rendering Modes

OpenGL defines 3 modes for rendering a polygon: point (GL_POINT), line (GL_LINE) and solid (GL_FILL). The default polygon rendering mode is solid.