I have a CSM which worked with forwrard shading, but now, I have deferred shading, but I'm in troubles with it.
In the CSM class, I have a Final Matrix each split:
[source]
float texOffset = 0.5f + (0.5f / (float)m_ShadowSize);
m_TextureMatrix = Matrix(0.5f, 0, 0, 0, 0, -0.5f,0, 0, 0, 0, 1, 0, texOffset, texOffset, -(2.5f / (float)m_ShadowSize), 1);
m_FinalMatrices = new Matrix[m_NumSplits];
[/source]
[source]
m_FinalMatrices[p_CurrSplit] = m_ViewProj * m_TextureMatrix;
[/source]
This matrices were correct with forward shading so I think the matrices are good.
The shadow map stored in a texture atlas (now 1024x1024) 4 * 512x512 maps.
Ofc, I pass the values to the shader.
In the shader, I have an exponential depth from the cam's eye position: (the stored depth map)
[source]float depthText = tex2D(samplerDepth, Texcoord);[/source]
and recompute the world position:
[source]float4 position;
position.x = Texcoord.x * 2.0f - 1.0f;
position.y = -(Texcoord.y * 2.0f - 1.0f);
position.z = depthText;
position.w = 1.0f;
position = mul(position, invViewProj);
position /= position.w;[/source]
Then, I compute the [0;camFar] linear depth
[source]float linearZ = (2.0f * camNear) / (camFar + camNear - depthText * (camFar - camNear));
linearZ *= camFar;[/source]
Now, I try to select the split:
[source]int id = 0;
if (Depth <= splitDistances[0])
{
}
else if (Depth <= splitDistances[1])
{
id = 1;
}
else if (Depth <= splitDistances[2])
{
id = 2;
}
else if (Depth <= splitDistances[3])
{
id = 3;
}
else
{
return 1.0f;
}[/source]
I think it works fine, because when I put an return value inside the statements, I saw the splits correctly.
From the last version of CSM shader, I compute a float4 value, which should be my texcoord for the shadow map
[source]float4 Shadow = mul(WorldPos, shadowMatrix[id]);
Shadow.xy /= Shadow.w;
return Shadow.z < tex2D(samplerShadow, Shadow);[/source]
It should work, but everyting is black.
Can anyone help me?
PS: sorry for my bad english
