Instancing : Different textures for instances
If all the textures are already in an atlas, aren't all cubes already using the same texture?
Well they all have access to the full atlas which contains all possible textures for a cube, but i still need set UV coordinates for each vertex of my cube.
I'll make things easier (because i am terrible at explaining things) by submitting my atlas and my code.
Here is the old atlas i was using :
And i initialized vertices of my unique cube type like such :
float oneQuarter = (float)1/3;
float twoQuarter = (float)2/3;
Vertex::Basic32 vertices[] =
{
{ XMFLOAT3(-0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(twoQuarter, 1) }, // 0 - front face - bottom left
{ XMFLOAT3(-0.5f, -0.5f, -0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(1, 1) }, // 1 - left face - bottom right
{ XMFLOAT3(-0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(0, 0) }, // 2 - bottom face - top left -> clone
{ XMFLOAT3(-0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(twoQuarter, 0) }, // 3 - front face - top left
{ XMFLOAT3(-0.5f, +0.5f, -0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(1, 0) }, // 4 - left face - top right
{ XMFLOAT3(-0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(oneQuarter, 1) }, // 5 - top face - bottom left
{ XMFLOAT3(+0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(1, 0) }, // 6 - front face - top right
{ XMFLOAT3(+0.5f, +0.5f, -0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(twoQuarter, 0) }, // 7 - right face - top left
{ XMFLOAT3(+0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(twoQuarter, 1) }, // 8 - top face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(1, 1) }, // 9 - front face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, -0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(twoQuarter, 1) }, // 10 - right face - bottom left
{ XMFLOAT3(+0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(oneQuarter, 0) }, // 11 - bottom face - top right
{ XMFLOAT3(-0.5f, -0.5f, +0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(twoQuarter, 1) }, // 12 - left face - bottom left
{ XMFLOAT3(-0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(1, 1) }, // 13 - back face - bottom right
{ XMFLOAT3(-0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(0, 1) }, // 14 - bottom face - bottom left
{ XMFLOAT3(-0.5f, +0.5f, +0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(twoQuarter, 0) }, // 15 - left face - top left
{ XMFLOAT3(-0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(oneQuarter, 0) }, // 16 - top face - top left -> clone
{ XMFLOAT3(-0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(1, 0) }, // 17 - back face - top right
{ XMFLOAT3(+0.5f, +0.5f, +0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(1, 0) }, // 18 - right face - top right
{ XMFLOAT3(+0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(twoQuarter, 0) }, // 19 - top face - top right -> clone
{ XMFLOAT3(+0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(twoQuarter, 0) }, // 20 - back face - top left
{ XMFLOAT3(+0.5f, -0.5f, +0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(1, 1) }, // 21 - right face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(oneQuarter, 1) }, // 22 - bottom face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(twoQuarter, 1) }, // 23 - back face - bottom left
};
Now, i have added a new texture to my atlas :
So, i changed the above code to calculate UV based on texture index in the atlas (maybe that's not the right approach, i don't know :s).
void GeometryBuilder::MakeCube(Geometry& box, int bottomTextureIndex, int topTextureIndex, int sideTextureIndex)
{
int numberOfTextures = 4;
float textureWidth = 1.0f / numberOfTextures;
Vertex::Basic32 vertices[] =
{
{ XMFLOAT3(-0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(textureWidth * sideTextureIndex, 1) }, // 0 - front face - bottom left
{ XMFLOAT3(-0.5f, -0.5f, -0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 1) }, // 1 - left face - bottom right
{ XMFLOAT3(-0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(textureWidth * (bottomTextureIndex), 0) }, // 2 - bottom face - top left -> clone
{ XMFLOAT3(-0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(textureWidth * sideTextureIndex, 0) }, // 3 - front face - top left
{ XMFLOAT3(-0.5f, +0.5f, -0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 0) }, // 4 - left face - top right
{ XMFLOAT3(-0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(textureWidth * (topTextureIndex), 1) }, // 5 - top face - bottom left
{ XMFLOAT3(+0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 0) }, // 6 - front face - top right
{ XMFLOAT3(+0.5f, +0.5f, -0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex), 0) }, // 7 - right face - top left
{ XMFLOAT3(+0.5f, +0.5f, -0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(textureWidth * (topTextureIndex + 1), 1) }, // 8 - top face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, 0.0f, -1.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 1) }, // 9 - front face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, -0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex), 1) }, // 10 - right face - bottom left
{ XMFLOAT3(+0.5f, -0.5f, -0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(textureWidth * (bottomTextureIndex + 1), 0) }, // 11 - bottom face - top right
{ XMFLOAT3(-0.5f, -0.5f, +0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex), 1) }, // 12 - left face - bottom left
{ XMFLOAT3(-0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 1) }, // 13 - back face - bottom right
{ XMFLOAT3(-0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(textureWidth * (bottomTextureIndex), 1) }, // 14 - bottom face - bottom left
{ XMFLOAT3(-0.5f, +0.5f, +0.5f), XMFLOAT3(-1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex), 0) }, // 15 - left face - top left
{ XMFLOAT3(-0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(textureWidth * (topTextureIndex), 0) }, // 16 - top face - top left -> clone
{ XMFLOAT3(-0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 0) }, // 17 - back face - top right
{ XMFLOAT3(+0.5f, +0.5f, +0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 0) }, // 18 - right face - top right
{ XMFLOAT3(+0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, +1.0f, 0.0f), XMFLOAT2(textureWidth * (topTextureIndex + 1), 0) }, // 19 - top face - top right -> clone
{ XMFLOAT3(+0.5f, +0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(textureWidth * (sideTextureIndex), 0) }, // 20 - back face - top left
{ XMFLOAT3(+0.5f, -0.5f, +0.5f), XMFLOAT3(+1.0f, 0.0f, 0.0f), XMFLOAT2(textureWidth * (sideTextureIndex + 1), 1) }, // 21 - right face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, -1.0f, 0.0f), XMFLOAT2(textureWidth * (bottomTextureIndex + 1), 1) }, // 22 - bottom face - bottom right
{ XMFLOAT3(+0.5f, -0.5f, +0.5f), XMFLOAT3(0.0f, 0.0f, +1.0f), XMFLOAT2(textureWidth * (sideTextureIndex), 1) }, // 23 - back face - bottom left
};
// other stuff...
}
This works, but forces me to call MakeCube for each type of cubes, and call DrawIndexedInstanced for each one of those.
- Pass uv-offsets for different cubes as instance-data and add them to the base-uvs in the shader.
- If all cells in the texture are of equal size you can load them into a texture array and pass an array-index as instance data.
The second method has the advantage that all the cutting can be done either offline or during load time and it avoids filtering artifacts around cell borders.
Hi eppo !
Actually i implemented you 1st approach yesterday night and it works fine (but with artefects on edges as you mentionned).
A friend just told me 5 minutes ago about texture arrays which is EXACTLY what i need as you also suggested, so i'll implement that tonight, thank you so much !
- If all cells in the texture are of equal size you can load them into a texture array and pass an array-index as instance data.
+2 for that one!
oh, wait! it won't do it!.....