Lighting with Cg 3.1
In this article I will demonstrate how to implement a basic lighting model using the Cg shader language. If you are unfamiliar with using Cg in your own applications, then please refer to my previous article titled Introduction to Shader Programming with Cg 3.1.
This article is an updated version of the previous article titled Transformation and Lighting in Cg. In this article, I will not use any deprecated features of OpenGL. I will only use the core OpenGL 3.1 API.
NVIDIA Cg
In this article I will introduce the reader to shader programming using the Cg shader programming language. I will use OpenGL graphics API to communicate with the Cg shaders. This article does not explain how use OpenGL. If you require an introduction to OpenGL, you can follow my previous article titled Introduction to OpenGL.
Vertex Buffer Object
OpenGL Extensions
Texturing and Lighting
Rendering Primitives
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.
NormalMapping
In this article, I will discuss a technique called normal mapping. Normal mapping is a shader technique that encodes pre-computed surface normals in a texture that can be used to add extra detail to a surface without the requirement of adding extra geometry. Before reading this article, you should have a basic understanding of OpenGL and you should know how to setup a Cg shader. For a review on OpenGL, you can refer to my previous article titled [Introduction to OpenGL for Game Programmers] and to learn how to incorporate Cg shaders in your own applications, you can refer to my article titled [Introduction to Cg Runtime with OpenGL].
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].
Continue reading