I am trying to implement the Shadow Mapping Technique using DirectX 11.
The Light Depth Buffer is the first pass and the camera is the second. In the first pass I write only the depth information with this vertex shader:
cbuffer CB_PER_INSTANCE : register(b0) {
float4x4 mWorld;
float4x4 mCamView;
float4x4 mCamProj;
float4x4 mNormal;
float4x4 mLightView;
float4x4 mLightProj;
};
void main(in float3 _vLocalPos : POSITION0, out float4 _vOutPos : SV_POSITION) {
_vOutPos = mul(mWorld, float4(_vLocalPos, 1.0f));
_vOutPos = mul(mLightView, _vOutPos);
_vOutPos = mul(mLightProj, _vOutPos);
}In the second pass, I render normally my scene using two shaders:
struct VS_IN {
float3 vLocalPos : POSITION0;
//There is other members here.
};
struct PER_INSTANCE_DATA {
float4x4 mWorld;
float4x4 mCamView;
float4x4 mCamProj;
float4x4 mNormal;
float4x4 mLightView;
float4x4 mLightProj;
};
cbuffer CB_PER_INSTANCE : register(cb0) {
PER_INSTANCE_DATA pidPerInstance;
};
struct VS_OUT {
float4 vViewPos : TEXCOORD0;
float3 vViewNormal : TEXCOORD1;
float2 vTexCoord : TEXCOORD2;
float4 vLightProjPos : TEXCOORD3;
};
void main(in VS_IN _viIn, out VS_OUT _voOut, out float4 _vOutPos : SV_POSITION) {
float4 vWorldPos = mul( pidPerInstance.mWorld, float4(_viIn.vLocalPos, 1.0f) );
//Camera Space.
_voOut.vViewPos = mul(pidPerInstance.mCamView, vWorldPos);
_vOutPos = mul(pidPerInstance.mCamProj, _voOut.vViewPos);
_voOut.vViewNormal = mul( (float3x3)(pidPerInstance.mNormal), _viIn.vLocalNormal );
_voOut.vTexCoord = _viIn.vLocalTexCoord;
//Light Space.
_voOut.vLightProjPos = mul(pidPerInstance.mLightView, vWorldPos);
_voOut.vLightProjPos = mul(pidPerInstance.mLightProj, _voOut.vLightProjPos);
}
struct VS_OUT {
float4 vViewPos : TEXCOORD0;
float3 vViewNormal : TEXCOORD1;
float2 vTexCoord : TEXCOORD2;
float4 vLightProjPos : TEXCOORD3;
};
Texture2D t2dDepthMap : register(t0);
SamplerState ssShadowSampler : register(s0) {
Filter = MIN_MAG_MIP_LINEAR;
AddressU = Wrap;
AddressV = Wrap;
};
void main(in VS_OUT _voOut, out float4 _vOutColor : SV_TARGET) {
float2 vLightProjTexCoord = _voOut.vLightProjPos.xy / _voOut.vLightProjPos.w;
vLightProjTexCoord.x = ( vLightProjTexCoord.x / 2.0f ) + 0.5f;
vLightProjTexCoord.y = ( vLightProjTexCoord.y / 2.0f ) - 0.5f;
float fThisDepthFromLight = _voOut.vLightProjPos.z / _voOut.vLightProjPos.w;
float fShadowMapPixelDepth = t2dDepthMap.Sample(ssShadowSampler, vLightProjTexCoord).r;
if ( fThisDepthFromLight > fShadowMapPixelDepth ) {
_vOutColor = float4(0.0f, 0.0f, 0.0f, 1.0f);
}
else {
_vOutColor = float4(1.0f, 0.0f, 0.0f, 1.0f);
}
}I use Intel GFA to debug one piece of frame. Here's the results:
Camera Z-Buffer:
Actually this doesn't matter since the technique uses only Light Projection for computations.
Light Z-Buffer:
What I got:
The Light is at (0.0, 0.0, 0.0) looking at (0.0, 0.0, 1.0) and uses a Perspective Projection. The last one was just an example of the final colors, but when I navigate to another point of view nothing happens, all I got is black colors.
I'm using the Debug Interface also, and everything is correct.
