Pong VS open-builder

Another method I think I noticed (probably not, not really sure what I'm talking about) is from Hopson97's open-builder game open-builder/chunk_vertex.glsl at master · Hopson97/open-builder · GitHub where texture coords are stored in the vertex shader. Would the idea for other block types for the above method to have a 2d array of the other block types textures like doors etc? Not sure about this method cause doesn't this require a vertex buffer which the "figured out an optimization" guy says is slow. If so that doesn't seem very sustainable.

For example, in this Notch article, he discussed using trilinear interpolation to speed up noise evaluation as well as to smooth out rough parts. But I tested, and both of his problems actually came mostly from using too many noise octaves. Minecraft used 16 octaves for each noise channel, and 8 octaves for the blending noise, when just 5-6 and 2-3 would be enough. The rest of the speed problems could be solved by implementing something to skip noise evaluations when they wouldn't matter, at least above/below max/min biome height if not dynamic octave skipping. See this screenshot difference.