# OpenGL (nvm solved)Question about D3dxEffect and multiple passes

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Sorry after thinking about it more, I figured out how it works. .............. Hi, I mainly have experience in OpenGL and little experience with Direct3D, but I've taken interest in the D3DXEffects, and I was looking at a tutorial where they mention that you can render the multiple passes within an effect like so: (totally pseudo code..)
//render object1 with effect1
for i = 0 to effect1.passNum
effect1.beginPass(i)
object1.drawGeom()
effect1.endPass(i)

...
...

//render objectN with effectN
for i = 0 to effectn.passNum
effectN.beginPass(i)
objectN.drawGeom()
effectN.endPass(i)


I am a bit newbie at this, but if I were to do something similar in OpenGL, I'd render all the objects' first passes onto the backbuffer, and then the subsequent passes onto a texture and then from there blended on top of the backbuffer (with depth testing off). So I don't understand how Direct3D with its D3DXEffects is doing it like the code I showed above. Or have I totally misunderstood what Direct3D is doing? Sorry if I wasn't very clear, or if this has been asked before. Thanks. [Edited by - andrew111 on March 11, 2010 9:08:02 AM]

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