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[CGameProgrammer]

I'm trying to write a routine to load a bitmap from a file, in Assembly. (I'm insane.) An error occurs when I try copying the BGR information from the bitmap to a temporary RGB array.

Here's the situation: Both have been successfully allocated, with EDX pointing to the source of BGR (blue,green,red) byte triplets, and EBX pointing to an array that I need to fill with R,G,B byte triplets. ECX holds the size (width*height) of the bitmap.

Code:

BeginLoop:
.If g_wBitsPerPixel == 24
	
Add EDX, 2 ; Position src ptr so we're at the red value.
Mov AL, Byte Ptr [EDX]
Mov Byte Ptr [EBX], AL
Inc EBX
Dec EDX ; Position src ptr so we're at the green value.
Mov AL, Byte Ptr [EDX]
Mov Byte Ptr [EBX], AL
Inc EBX
Dec EDX ; Position src ptr so we're at the blue value.
Mov AL, Byte Ptr [EDX]
Mov Byte Ptr [EBX], AL
Inc EBX
Add EDX, 3 ; Position src ptr for next loop.
.EndIf
Dec ECX
Cmp ECX, 0
JNE BeginLoop ; If ECX != 0 goto BeginLoop

Somewhere in there, an error is occuring. Any ideas?

------------------
~CGameProgrammer( );

[This message has been edited by CGameProgrammer (edited October 05, 1999).]

[Jim Adams]

Are you taking into account that the bitmap width must be a multple of 4?

Jim