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Direct Draw and 24/32 bit PCX/Bitmap Loading

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I''ve been stumped for a long time on loading in 24 bit bitmaps or pcx files into a direct draw surface. what im looking for is a function of roughly the form LPDIRECTDRAWSURFACE4 LoadPic(int width, int height, int mem_flags, char *filename) to open the file, create a dd surface of correct size, and put the picture into the surface (the picture size and surface size being the same). Any help on 24 or 32 PCX or bitmaps would be helpful.

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Guest Anonymous Poster
I''ve seen this question on this board alot, but no one ever posts code
on how to load 24-bit PCX files. Here''s the easy part, the header.
Maybe someone else can finish it:


typedef struct _PCXFILEHEADER {

BYTE Identifier; // 0xA0 = Z-Soft
BYTE Version; // 5 = palettes and 24-bit PCX files
BYTE Encoding; // 1 = RLE
BYTE BitPerPixel; // 1,2,4,8 (8 = 24-bit files)
WORD XStart; // Image dimensions (0,0,width-1,height-1)
WORD YStart;
WORD XEnd;
WORD YEnd;
WORD HorzRes; // 300 = horizontal resolution (dpi)
WORD VertRes; // 300 = vertical resolution (dpi)
BYTE Palette[48];
BYTE Reserved1; // zero
BYTE NumBitPlanes; // 3 = 24-bit
WORD BytesPerLine; // scanline (must be even)
WORD PaletteType; // 1=color, 0=b/w
WORD HorzScreenSize;
WORD VertScreenSize;
BYTE Reserved2[54]; // all zero

} PCXFILEHEADER, *PCXFILEHEADER_PTR;



Basically, the header for any PCX file is always 128 bytes. For
a 24-bit PCX file, there is no 768 byte palette or any 1 byte 0C marker,
so the RLE data is directly after the header. Then you have to decode
the pixel runs. But, you''re not finished yet. After the data is
decoded, you have to re-order the RGB data so it is in the order of
R-G-B respectively. That''s because when the PCX file was written,
the RGB planes were separated first, then encoded. Finally, you can
copy it to a DD surface.

Get the file format info at:

http://www.wotsit.org/

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