Ocean simulation part two: using the fast Fourier transform

In this post we will analyze the equations for the statistical wave model presented in Tessendorf's paper[1] on simulating ocean water. In the previous post we used the discrete Fourier transform to generate our wave height field. We will proceed with the analysis in order to implement our own fast Fourier transform. With this implementation at our disposal we will be able to achieve interactive frame rates. Below are two screen captures of our result. The first uses a version of the shader Read more [...]

Ocean simulation part one: using the discrete Fourier transform

In this post we will implement the statistical wave model from the equations in Tessendorf's paper[1] on simulating ocean water. We will implement this model using a discrete Fourier transform. In part two we will begin with the same equations but provide a deeper analysis in order to implement our own fast Fourier transform. Using the fast Fourier transform, we will be able to achieve interactive frame rates. Below are two screen captures. The first is a rendering of the surface using some Read more [...]

Tangent space normal mapping with GLSL

In the previous post we discussed lighting and environment mapping, and our evaluation of the lighting contribution was performed in view space. Here we will discuss lighting in tangent space and extend our lighting model to include a normal map. If we apply a texture to a surface, then for every point in the texture we can define a set of vectors that are tangent to that point. Once we transform our light vector, halfway vector, and normal vector into tangent space, we can use the normal map Read more [...]

Lighting and environment mapping with GLSL

In this post we will expand on our skybox project by adding an object to our scene for which we will evaluate lighting contributions and environment mapping. We will first make a quick edit to our Wavefront OBJ loader to utilize OpenGL's Vertex Buffer Object. Once we can render an object we will create a shader program to evaluate the lighting and reflections. Below are a couple of screen grabs of the final result. A couple of video captures are below. Read more [...]

Rendering a skybox using a cube map with OpenGL and GLSL

I realized in my previous posts the use of OpenGL wasn't up to spec. This post will attempt to implement skybox functionality using the more recent specifications. We'll use GLSL to implement a couple simple shaders. We will create an OpenGL program object to which we will bind our vertex and fragment shaders. A Vertex Buffer Object will be used to store our cube vertices and another to store the indices for the faces. Using a cube map texture will allow our vertices to double as texture coordinates. Read more [...]