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Pyrogame

DX11 [Solved] DX11 - AlphaBlending - Effect states

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Hi, I know, how to render alpha blended in DX9. This was easy. I know, that this is easy in DX11 as well, BUT I can't figure it out, what I have to do to enable this ^^. I know, that alpha blending is always enabled and that I have to control the behaivour with the blend state filters. I output this color in my pixel shader: float4(1, 1, 1, 0.1f); But I see a white rectangle. If I change the 1's, then I see, that the color of the rectangle changes (means, it is rendered correctly). But I can change the alpha value, even to 0, the rectangle remains opaque. (My background is blue.) I tried this render states: BlendState BState { BlendEnable[0] = FALSE; RenderTargetWriteMask[0] = 0xF; BlendOpAlpha = ADD; SrcBlend[0] = SRC_COLOR; DestBlend[0] = DEST_COLOR; SrcBlendAlpha[0] = SRC_ALPHA; DestBlendAlpha[0] = INV_SRC_ALPHA; }; In my technique I did this: SetBlendState(BState, float4(0.0f, 0.0f, 0.0f, 0.0f), 0xF); And I played with the values, but I didn't get what I want: simple alpha blending. Can someone explain me, what each of this blend states do, and what the values of SetBlendState(BState, float4(0.0f, 0.0f, 0.0f, 0.0f), 0xF); means? And what I have to do, to enable alpha blending, so my rectangle becomes transparent? [Edited by - Pyrogame on March 13, 2010 10:35:27 AM]

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You don't need to change the RenderTargetWriteMask, and the Src/DestBlendAlpha are for blending the actual alpha channel, which doesn't seem to be what you want, so you can remove them too. The only thing you should need to do is to set SrcBlend to SRC_ALPHA and DestBlend to INV_SRC_ALPHA, as it is the color you want blended, using the alpha to specify how opaque that color should be. And you should set BlendEnable to TRUE.. it's FALSE in the blendstate you posted, which means blending is disabled.

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