Hi...

I think i can answer 2.

There are two ways to see it.
In the NV_texture_shader world (ps1.0 - ps1.3), dudv maps store an offset vector for adding it to a texture coordinate per-pixel in case to read an other texture. It's something like this :

float2 dudv = tex2D(dudvMap, texCoord);float2 newTexCoord = texCoord + dudv;float4 texSample = tex2D(diffuseTex, newTexCoord);

The above thing happens automatically with texture shaders.

On the other hand, in the ARB_fragment_program world (ps2.0 and ps3.0) dudv is just a texture with 2 16-bit channels. You can store whatever you like in it, and use it however you like.

Hope that helps.

HellRaiZer

I'm not sure what may be wrong but i don't think that dudv texture is the problem. There may be a problem with the matrix you are using for projecting the reflection. I say that because as long as you get the disturbance on the surface, the dudv texture is ok.

Sorry but i haven't implemented planar texture reflection yet so i can't help you with the details of the projection. I'm sure someone else can help you more.

HellRaiZer

EDIT :
Or there maybe a problem with the quad's tesselation. How many quads are there? If it's only one, try to subdivide it more to see what will happen.