OpenGL Extensions

OpenGL Extensions

OpenGL Extensions

In this article I will talk about OpenGL extensions. Every extension is defined by an extension specification. I will explain how to read the extension specification so that you will know how to use the extensions. I will also show how you can check for the existence of extensions and how to initialize extensions in your own source code. I will show how you can use GLEW to query and use extensions with very little extra effort.
I assume the reader is familiar with the C++ programming language. If you want to know how to start programming in OpenGL, refer to my previous article titled Introduction to OpenGL.

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Introduction to OpenCL

OpenCL

OpenCL

In this article I will provide a brief introduction to OpenCL. OpenCL is a open standard for general purpose parallel programming across CPUs, GPUs, and other programmable parallel devices. I assume that the reader is familiar with the C/C++ programming languages. I will use Microsoft Visual Studio 2008 to show how you can setup a project that is compiled with the OpenCL API.

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OpenGL Interoperability with CUDA

Postprocess Effect

Postprocess Effect

In this article I will discuss how you can use OpenGL textures and buffers in a CUDA kernel. I will demonstrate a simple post-process effect that can be applied to off-screen textures and then rendered to the screen using a full-screen quad. I will assume the reader has some basic knowledge of C/C++ programming, OpenGL, and CUDA. If you lack OpenGL knowledge, you can refer to my previous article titled Introduction to OpenGL or if you have never done anything with CUDA, you can follow my previous article titled Introduction to CUDA.

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CUDA Memory Model

CUDA Memory Model

CUDA Memory Model

In this article, I will introduce the different types of memory your CUDA program has access to. I will talk about the pros and cons for using each type of memory and I will also introduce a method to maximize your performance by taking advantage of the different kinds of memory.
I will assume that the reader already knows how to setup a project in Microsoft Visual Studio that takes advantage of the CUDA programming API. If you don’t know how to setup a project in Visual Studio that uses CUDA, I recommend you follow my previous article titled [Introduction to CUDA]
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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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Normal Mapping with Cg and OpenGL

NormalMapping

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].

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GPU Skinning of MD5 Models in OpenGL and Cg

Bob with Lamp (GPU Skinning)

Bob with Lamp (GPU Skinning)

This tutorial builds upon the previous article titled [Loading and Animating MD5 Models with OpenGL]. It is highly recommended that you read the previous article before following this one. In this tutorial, I will extend the MD5 model rendering to provide support for GPU skinning. I will also provide an example shader that will perform the vertex skinning in the vertex shader and do per-fragment lighting on the model using a single point light. For a complete discussion on lighting in CgFX, you can refer to my previous article titled [Transformation and Lighting in Cg].
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Transformation and Lighting in Cg

Spotlight Shader Effect

Spotlight Shader Effect

In this article I will demonstrate how to implement a basic lighting model using the Cg shader language. In this article, I assume the reader is familiar with the OpenGL graphics API and how to setup an application that uses OpenGL. If you want to see how you can setup an application that can be used to do OpenGL graphics rendering, you can refer to my previous article titled [Introduction to OpenGL for Game Programmers].

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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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Multi-textured Terrain in OpenGL


Terrain Sample

Terrain Sample

In this article I will demonstrate one possible way to generate multi-textured terrain using only the OpenGL rendering pipeline. This demo uses the GL_ARB_multitexture and GL_ARB_texture_env_combine OpenGL extensions to do the multi-textured blending based on the height of the vertex in the terrain.  I will also use the GL_ARB_vertex_buffer_object extension to store the terrain’s vertex information in the GPU memory for optimized rendering.

I will not show how to setup an application that uses OpenGL.  If you would like to review how to setup an OpenGL application you can refer to my previous article titled “Introduction to OpenGL for Game Programmers“.

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