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Lighting a texture

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Hello, I got some trouble lighting my ground texture. If I don't use a texture all goes fine, you can see clearly some lighted area and an unlighted one. But when I apply a texture to the geometry the lighting effect doesn't work anymore and you see the entire textured geometry lite (so no lighted and unlighted areas anymore, like it does in without applying a texture to the geometry). Can anyone help me with this?

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Need to post:

- What API you're using (OpenGL/DirectX)
- What draw commands you're issuing
- If possible, code or screen shots

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I'm using DirectX (else I would have posted it in OpenGL forum).

Here is the source of the render function:

VOID Render()
{
g_pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER,
D3DCOLOR_XRGB(0,0,0), 1.0f, 0);
// Begin the scene
if(SUCCEEDED(g_pd3dDevice->BeginScene()))
{
SetupMatrices();
SetupLights();
// Samplerstages here..

// Texture crap here
g_pd3dDevice->SetTexture(0, g_pTB1);
g_pd3dDevice->SetTexture(1, g_pTB2);
g_pd3dDevice->SetTexture(2, g_pTB3);
g_pd3dDevice->SetTextureStageState(0, D3DTSS_TEXCOORDINDEX, 0);
g_pd3dDevice->SetTextureStageState(1, D3DTSS_TEXCOORDINDEX, 0);
g_pd3dDevice->SetTextureStageState(2, D3DTSS_TEXCOORDINDEX, 0);

SetTSS(0, D3DTSS_COLOROP, D3DTOP_SELECTARG1); // just select arg1
SetTSS(0, D3DTSS_COLORARG1, D3DTA_TEXTURE); // which is texture color
SetTSS(0, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1); // just select arg1

SetTSS(1, D3DTSS_COLOROP, D3DTOP_BLENDDIFFUSEALPHA); // Use alpha from stage 0 to blend
SetTSS(1, D3DTSS_COLORARG1, D3DTA_CURRENT); // and the stage 0's color
SetTSS(1, D3DTSS_COLORARG2, D3DTA_TEXTURE);
SetTSS(1, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1); // Just keep alpha stage active
SetTSS(1, D3DTSS_ALPHAARG1, D3DTA_CURRENT);

if(bGrid)
{
SetTSS(2, D3DTSS_COLOROP, D3DTOP_BLENDTEXTUREALPHA);
SetTSS(2, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1);
SetTSS(2, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);

SetTSS(3, D3DTSS_COLOROP, D3DTOP_DISABLE);
SetTSS(3, D3DTSS_ALPHAOP, D3DTOP_DISABLE);
}
else
{
SetTSS(2, D3DTSS_COLOROP, D3DTOP_DISABLE);
SetTSS(2, D3DTSS_ALPHAOP, D3DTOP_DISABLE);
}

for(int i = 0; i < MapX * MapY; i++)
g_pMesh[i]->DrawSubset(0);

g_pd3dDevice->EndScene();
}
g_pd3dDevice->Present(NULL, NULL, NULL, NULL);

}



Here is the SetupLight function:

VOID SetupLights()
{
D3DMATERIAL9 d3dMaterial;
ZeroMemory( &d3dMaterial, sizeof(d3dMaterial) );

d3dMaterial.Diffuse.r = d3dMaterial.Ambient.r = 1.0f;
d3dMaterial.Diffuse.g = d3dMaterial.Ambient.g = 1.0f;
d3dMaterial.Diffuse.b = d3dMaterial.Ambient.b = 1.0f;
d3dMaterial.Power = 0;

g_pd3dDevice->SetMaterial(&d3dMaterial);

D3DLIGHT9 d3dLight;

//Initialize the light structure.
ZeroMemory(&d3dLight, sizeof(D3DLIGHT9));

//Set up a white point light at (0, 0, -10).
d3dLight.Type = D3DLIGHT_POINT;

d3dLight.Diffuse.r = d3dLight.Diffuse.g = d3dLight.Diffuse.b = 1.0f;
d3dLight.Ambient.r = d3dLight.Ambient.g = d3dLight.Ambient.b = 0.5f;

d3dLight.Specular.r = 0.0f;
d3dLight.Specular.g = 0.0f;
d3dLight.Specular.b = 0.0f;

d3dLight.Position = D3DXVECTOR3(8.0f, 8.0f, 4.0f);

d3dLight.Attenuation0 = 1.0f;
d3dLight.Attenuation1 = 0.0f;
d3dLight.Attenuation2 = 0.0f;
d3dLight.Range = 8.0f;

//Assign the point light to our device in poisition (index) 0
g_pd3dDevice->SetLight(0, &d3dLight);

//Enable our point light in position (index) 0
g_pd3dDevice->LightEnable(0, TRUE);

//Turn on lighting
g_pd3dDevice->SetRenderState(D3DRS_LIGHTING, TRUE);

//Set ambient light level
g_pd3dDevice->SetRenderState(D3DRS_AMBIENT, D3DCOLOR_XRGB(32, 32, 32));

}



I make use of the mesh->Drawsubset command.

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Sorry. I wasn't paying attention to the forum.

I believe the way texture stages and lighting work is that the lighting is calculated per-vertex and then saved in vertex color, which is then interpolated. So one of your texture stages needs to be set to modulate the output fragment by the interpolated vertex color - I believe it's D3DTA_DIFFUSE.

Hope that helps.

Tom

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Quote:
Original post by ParadigmShift
Sorry. I wasn't paying attention to the forum.

I believe the way texture stages and lighting work is that the lighting is calculated per-vertex and then saved in vertex color, which is then interpolated. So one of your texture stages needs to be set to modulate the output fragment by the interpolated vertex color - I believe it's D3DTA_DIFFUSE.

Hope that helps.

Tom


Yep, it did the job. Thank you.

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