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Revisiting Shadow Mapping =)

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I had been working on shadow mapping a while back, to implement a basic system for it, but never got it finished and working. I am now back at that point, and have everything in place, but am not getting the proper results! I apologize in advanced for the length of material to look through!

My shadow map texture and depthstencil creation

////Create shadow map texture
if(_d3dDevice->CreateTexture(512, 512, 1, D3DUSAGE_RENDERTARGET, D3DFMT_R32F, D3DPOOL_DEFAULT, &_shadowMap, 0) != D3D_OK)
ErrorMessenger::ReportMessage("Failed to create shadow map texture!", __FILE__, __LINE__);

////Create depth map
if(_d3dDevice->CreateDepthStencilSurface(512, 512, D3DFMT_D16, D3DMULTISAMPLE_NONE, 0, true, &_dssShadow, 0) != D3D_OK)
ErrorMessenger::ReportMessage("Failed to create depth surface!", __FILE__, __LINE__);

Map generation shader

void vsRenderShadowMap(float4 iPos : POSITION0,
out float4 oPos : POSITION0,
out float oDepth : TEXCOORD0)
float4 vWorldPos = mul(iPos, world);
float4 vLightViewPos = mul(vWorldPos, lView);
oPos = mul(vLightViewPos, lProj);

oDepth = oPos.z / oPos.w;

float4 psRenderShadowMap(float iDepth : TEXCOORD0) : COLOR0
return float4(iDepth, 0.0f, 0.0f, 1.0f);

Map generation render loop

//Back up old render targets
IDirect3DSurface9* oldDS;

IDirect3DSurface9* oldRT;
_d3dDevice->GetRenderTarget(0, &oldRT);

//Set new render target and new depth surface
IDirect3DSurface9* shadowSurf;
_shadowMap->GetSurfaceLevel(0, &shadowSurf);
_d3dDevice->SetRenderTarget(0, shadowSurf);

//Clear the render target and begin to render
_d3dDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);


//Loop through and draw everything
for(int i = 0; i < _worlds[_views[view].world].Size(); i++)
if(_worlds[_views[view].world]->GetEffect()->SetTechnique("RenderShadowMap") != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set technique!", __FILE__, __LINE__);

if(_worlds[_views[view].world]->GetEffect()->SetMatrix("lView", &lightView) != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set world matrix!", __FILE__, __LINE__);

if(_worlds[_views[view].world]->GetEffect()->SetMatrix("lProj", &lightProj) != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set projection matrix!", __FILE__, __LINE__);

//Draw the item


//After drawing to the shadow map, set old render targets back.
_d3dDevice->SetRenderTarget(0, oldRT);


Shader to render using the shadowmap

void vsRenderSceneWithLight(float4 iPos : POSITION0,
float4 iNormal : NORMAL,
float2 iUV : TEXCOORD0,
out float4 oPos : POSITION0,
out float2 oUV : TEXCOORD0,
out float4 oLightPos : TEXCOORD1,
out float oDepth : TEXCOORD2)
//Get the vertices world position
float4 vWorldPos = mul(iPos, world);

//Transform the position to the camera view and perspective
float4 vViewPos = mul(vWorldPos, cView);
oPos = mul(vViewPos, cProj);

//Get the pixel depth from the view of the camera
oDepth = (oPos.z / oPos.w);

//Transform the position to the light view and perspective
float4 lViewPos = mul(vWorldPos, lView);
oLightPos = mul(lViewPos, lProj);

oUV = iUV;

float4 psRenderSceneWithLight(float2 iUV : TEXCOORD0,
float4 iLightPos : TEXCOORD1,
float iDepth : TEXCOORD2) : COLOR0
//Get UV coordinates for sampling depth map
iLightPos.xyz /= iLightPos.w;
float2 depthUV = iLightPos.xy * float2(0.5f, -0.5f) + 0.5f;

//Sample depth map using new UV coordinates
float lDepth = tex2D(ShadowMapSampler, depthUV).x;

//Returning test color before including my texture colors
if(iDepth >= lDepth)
return float4(0.0f, 0.0f, 0.0f, 1.0f);

return float4(1.0f, 1.0, 1.0f, 1.0f);

Render loop using the shadow map

IDirect3DSurface9* buffer;
_views[view].swapChain->GetBackBuffer(0, D3DBACKBUFFER_TYPE_MONO, &buffer);
_d3dDevice->SetRenderTarget(0, buffer);

_d3dDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, _views[view].targetClear, 1.0f, 0);


//Loop through and draw everything in the world
for(int n = 0; n < _worlds[_views[view].world].Size(); n++)
//Set lighting parameters
//Set the lighting technique
ErrorMessenger::ReportMessage("Failed to set technique!", __FILE__, __LINE__);

//Set shadow map texture
if(FAILED(_worlds[_views[view].world][n]->GetEffect()->SetTexture("tShadowMap", _shadowMap)))
ErrorMessenger::ReportMessage("Failed to set texture!", __FILE__, __LINE__);
else if(!lighting)
if(_worlds[_views[view].world][n]->GetEffect()->SetTechnique("RenderSceneWithoutLight") != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set technique!", __FILE__, __LINE__);
if(_worlds[_views[view].world][n]->GetEffect()->SetTechnique("PickObject") != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set technique!", __FILE__, __LINE__);

//Set view and projection matrices
if(_worlds[_views[view].world][n]->GetEffect()->SetMatrix("cView", &_camera->GetViewViewMatrix(view)) != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set View Matrix!", __FILE__, __LINE__);

if(_worlds[_views[view].world][n]->GetEffect()->SetMatrix("cProj", &_camera->GetViewProjectionMatrix(view)) != D3D_OK)
ErrorMessenger::ReportMessage("Failed to set Projection Matrix!", __FILE__, __LINE__);

//Draw the item(world matrix is set in here)

//Kill object if requested to


_views[view].swapChain->Present(0, 0, 0, 0, 0);


I know its kinda a lot to look through, but just by doing a quick read through, is there anything that stands out as wrong? Here is the shadow map I am getting. Edit: I have looked at my depth surface in pix, and it looks fine. This blue map is just saving the surface to file


And this is the in-game result

It seems that the distance of my camera effects what is colored

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Hi, i think that [color="#000000"]oPos[color="#666600"].[color="#000000"]z [color="#666600"]/[color="#000000"] oPos[color="#666600"].[color="#000000"]w shall be done in pixel shader instead of vertex shader. also you should add small value to depth (during depth comparison)

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