Screenshots029

From CSP

Using the very basic mulitexturing extension of OpenGL it is easy to add a detail texture to the terrain. The resulting texturelooks quite similar to the that produced by Demeter. This helps with the sense of speed down low, and will serve as a temporarysolution until we get more fancy multitexturing implemented. The detail texture in the shot below is rather strong, which looksgood at long range here but shows obvious repetition in flat areas at high altitude.

Wrapping the multitexturing up in a simple class, it's now easy to add as many detail textures as your graphics card has textureunits. On a !GeForce4 that's four texture units, which means the basic color/shadow map plus three detail textures. The screenshot below combines a 4 km arial photo of fields/forest with a 512 m bump-mapped plasma texture, and a 128 m plasma texture. Allthese textures are 512x512 and are rendered single pass. The final color is the product of the various textures, so it comes out a bit dark currently. To make the details easier to see I've brightened the image and stretched the contrast a bit:

The 4 km texture is subtle and large enough to fade into the distance at med-high altitude without being noticibly repetitive, while the finer details give a reasonably good sense of speed down low. Seeing the same texture wrapping everything is far from ideal, however.