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CzarKirk

OpenGL Convert this OpenGL to DirectX

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CzarKirk    100
Hi, I've written these code fragments in OpenGL but now need to convert them to DirectX with which I am less familiar. This is the only part I'm missing to get my game working with both ogl and dx!!

The code is in BlitzMax but you can give it in C++ and I will figure out the rest.

[code]Case DIRECTBLEND
glEnable GL_BLEND
glBlendFunc GL_ONE,GL_ZERO
glDisable GL_ALPHA_TEST
Case MASKONBLEND
glEnable GL_BLEND
glBlendFunc GL_DST_ALPHA,GL_ONE_MINUS_DST_ALPHA
glDisable GL_ALPHA_TEST
Case MASKOFFBLEND
glEnable GL_BLEND
glBlendFunc GL_ONE_MINUS_DST_ALPHA,GL_DST_ALPHA
glDisable GL_ALPHA_TEST

...

I want to write only the alpha channel
glColorMask GL_FALSE, GL_FALSE, GL_FALSE, GL_TRUE
draw something
glColorMask GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE
[/code]


Somebody has suggested this for part of the commands, but he's unsure for the others or if it's right.

[code]Case MASKONBLEND
_d3dDev.SetRenderState D3DRS_ALPHABLENDENABLE,True
_d3dDev.SetRenderState D3DRS_ALPHATESTENABLE,False
_d3dDev.SetRenderState D3DRS_SRCBLEND,D3DBLEND_DESTALPHA
_d3dDev.SetRenderState D3DRS_DESTBLEND,D3DBLEND_INVDESTALPHA
Case MASKOFFBLEND
_d3dDev.SetRenderState D3DRS_ALPHABLENDENABLE,True
_d3dDev.SetRenderState D3DRS_ALPHATESTENABLE,False
_d3dDev.SetRenderState D3DRS_SRCBLEND,D3DBLEND_INVDESTALPHA
_d3dDev.SetRenderState D3DRS_DESTBLEND,D3DBLEND_DESTALPHA[/code]

I am looking for the code to be compatable with both DirectX 7 and DirectX 9.

Thank you for any help you can give.

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Adam_42    3629
D3D has D3DBLEND_ONE and D3DBLEND_ZERO which you can use for the first case.

For the colour write mask you want to set D3DRS_COLORWRITEENABLE to some combination of D3DCOLORWRITEENABLE_ALPHA, D3DCOLORWRITEENABLE_BLUE, D3DCOLORWRITEENABLE_GREEN, and D3DCOLORWRITEENABLE_RED.

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