Projected Shadow Mapping with Cg and OpenGL

Projective Shadow Mapping

Projective Shadow Mapping

In this article, I will show how to implement projective shadow mapping in OpenGL using Cg shaders.
The basis of this post comes from the article titled [Transformation and Lighting in Cg]. I will assume the reader has a basic understanding of OpenGL and already knows how to setup an application that uses OpenGL. If you require a refresher on setting up an application using OpenGL, you can refer to my previous article titled [Introduction to OpenGL for Game Programmers].

I will take advantage of a few OpenGL extensions such as GL_ARB_framebuffer_object to create a offscreen framebuffer to render to and and GL_ARB_texture_border_clamp for clamping to the border color of the projective textures.

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Environment Mapping with Cg and OpenGL

Environment Mapping with Cg

Environment Mapping

In this article I will demonstrate an effect called Environment Mapping. Environment mapping attempts to simulate the effect of reflective or refractive surfaces in a shader rasterizer. I assume the reader has a basic understanding of OpenGL and Cg. If you require an introduction in OpenGL, you can refer to my article titled [Introduction to OpenGL for Game Programmers]. And for an introduction to Cg, you can refer to my article titled [Introduction to Cg Runtime with OpenGL].
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Introduction to Cg Runtime with OpenGL

Cg Runtime - Example 2

Cg Runtime - Example 2

In this article I will provide a brief introduction to the Cg runtime and I will show a very simple example that uses the Cg shader language.

I will assume that the reader has some basic knowledge of OpenGL and how to create an application that uses OpenGL to render graphics to the screen. If you need a brief introduction to OpenGL, you can refer to my article [Introduction to OpenGL for Game Programmers]

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