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NightZero

Blt vs. BltFast

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Hi! Because of performance reasons with my old graphicscard I have to use BltFast when flipping the backbuffer to the frontbuffer in windowed mode. But why is the backbuffer smaller when I use BltFast? I don''t strech it with the Blt () funktion! When using BltFast there becomes a black line in the bottom of the window about 20 pixels hight. So it becomes smaller vertical. Anyone knows why? Here is the code: //OK with the Blt-function. g_Display->GetBackBuffer()->Blt(&dest, g_Surface- >GetDDrawSurface(), NULL, DDBLT_WAIT, NULL); //Smaller with BltFast in vertical line?! g_Display->GetBackBuffer()->BltFast(dest.left, dest.top, g_Surface->GetDDrawSurface(), NULL, NULL); Regards, Mattias

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Guest Anonymous Poster
Here are a couple of things to consider:

( 1 ) BltFast DOES NOT support scaling
( 2 ) In windowed mode you MUST account for the size of the frame window, menu, tool bars, etc. You can do this by using AdjustWindowRect. This is important because the client area of your windowed mode app must match your surface size exactly. Otherwise BltFast will not work properly.

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