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Semi-transparent model

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Hi, im using c++ and im trying to figure out how can i make a model on the screen 50% transparent of 75%. My end goal is being able to fade the model in and out of view. Thanks for any help, -Dave

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Huh, you need to be more specific ... do you use the old fixed pipeline or a pixel shader ?

First, you need to make sure you have alpha blending enabled with:

If you use a pixel shader, you can only add and set a constant and multiply the alpha component with it before returning the result.

If you use the old fixed pipeline (you should not because it's pretty much dead), you could do something like:

lpD3DDevice->SetTextureStageState( 0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
lpD3DDevice->SetTextureStageState( 0, D3DTSS_ALPHAARG2, D3DTA_TFACTOR);
lpD3DDevice->SetTextureStageState( 0, D3DTSS_ALPHAARGOP, D3DTOP_MODULATE);
lpD3DDevice->SetRenderState(D3DRS_TEXTUREFACTOR, fadeFactor << 24);
where fadeFactor is between 0 (completely transparent) and 255 (opaque)

Also, if you want to achieve good result, you'll need to render your model twice, once writing only in the z-buffer and once normally after with z testing on to avoid sorting problems:

lpD3DDevice->SetRenderState(D3DRS_COLORWRITEENABLE, 0);
// render you mesh
// render your mesh again

hope I understood your question correcly ;) and it help

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