The Plan
I decided to treat the procedural pattern generation as the generation of a "texture," and thus created a Texture class. A Texture object is created with a width and height and stores an array of unsigned chars, it's length being width * height * 3 (it stores the RGB values for every "pixel" of the "texture").When the ray is cast out from the camera and intersects with a surface, we translate that point of intersection into local coordinates (u, v) relative to some origin on the surface. The easiest case for this is a Polygon which is why it was the focus of this checkpoint. Determining relative (u, v) coordinates shouldn't be too difficult for other objects, however, and I plan on doing so in a later release.
The local (u, v) coordinates then can be used to easily determine the corresponding color from the Texture object. The (u, v) coordinates lying outside the dimensions of the array can be easily handled in a manner similar to actual texture mapping; either repeat the image or stretch the nearest legitimate pixel.
The biggest benefit of using this setup, however, is that it can easily be extended to allow for actual textures to be loaded in. All you have to do is convert a texture into an array of RGB values, which the Simple OpenGL Image Library can actually do for us.
Known Problems
- Shadows are finally casting correctly (WOO!), but ambient light does not work as expected. Illuminating scene fully with ambient light should eliminate all shadows; currently does not.
- Objects are still one-sided and I'm still not sure if I like this or not.
- Loading in textures and converting to RGB values is surprisingly slow using SOIL. Need to figure out why or find a better method.
- There's no real concept of "texture mapping" yet, so when textures are loaded in they're stretched almost unrecognizably.
Results
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| Basic - Procedural Shaded Polygon |
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