Latest days I've been working on the latest hype (or not) of 3d engine : megatexture ! However, I didn't want it to alter the toolchain with specific texturing tools.

After some thinking, I think I came up with an interesting idea :

• Mega texture (including atlas) is built on the fly, with a given texture block granularity (let's say 32 * 32 texels).
• To avoid wasting resource, tiling is detected via a simple CRC check of texture blocks when a texture is uploaded.
• Texture could also be checked for duplication before uploading (not sure of that, still to be determined).
• UV mapping of objects get remapped at loading.

My hope is to end with a system where you could paint in the middle of a very big tiled texture very easily while consuming minimum texture size. In fact, megatexture, or the idea of virtualizing textures is a neat idea, but some care should be taken (i.e. still use of tiling/texture reuse), because a 32k*32k seems a lot, but stretched over a very big terrain, it could end up with a very bad resolution.

My hope is it will be merged in the source within few days.

Update : After some prototyping, seems to behave fine (no artifact). I gonna take a look at perfhud to check if it's not too heavy (on pixel-shader side). In fact, with bilinear filtering, 8 texture lookups are needed.

Update 2 : Pixel shader complexity was increasing too much. As a result, I switched the way to do it and I ended up with border uploaded. Now pixel shader is basically two tex2D lookup, a frac and few additions/multiplications. It was a bit painful to get perfect mipmaps (including border) without any shifting artifact.

Latest days I've been rewriting the render layer of the project to match D3D10 and upcoming OpenGL Longs Peak.
Sometimes it's hard to keep D3D9 compatibility (especially about index buffer indice size fixed at creation time and stuff like that).

Nevertheless it should end up in an API very optimized toward next-gen hardware. Even if it took some time, it should give me a render framework way more clean to start from.

By the way, I've also written the base of a software depth renderer to use with HOM (Hierarchical Occlusion Culling).