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Nemesis2k2

Petty little thing about TGA loader source.....

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This is just a note to NeHe about a few lines in the TGA loader source that have been nagging at me for awhile now.
texture->width  = tga.header[1] * 256 + tga.header[0];
texture->height = tga.header[3] * 256 + tga.header[2];
It's bad form to do this arithmetically IMHO. You can either do it logically, or use a typecast on the pointer, and rely on the endian order to do the byteswap for you. For example:
//Obtaining value using logical shift to promote second byte,

//and binary OR to combine with first byte:

texture->width  = (tga.header[1] << 8) | tga.header[0];
texture->height = (tga.header[3] << 8) | tga.header[2];

//Obtaining value using typecast on pointer, and relying

//on little endian byte order to perform byteswap.

texture->width  = *((short*)&(tga.header[0]));
texture->height = *((short*)&(tga.header[2]));
The second method is rather experimental for me, and I don't know if it'd be considered messy or bad form by more experienced programmers, but the logical method shown in the first example is a much better way to obtain the values than using multpilcation and addition IMO, and even though speed is not any real issue in this perticular instance, I think it would be significantly faster if the two were compared. Note that this is not meant as criticism, merely as a suggestion for improvement. EDIT: This damn thing keeps screwing up my source tags. [edited by - Nemesis2k2 on September 23, 2003 8:28:32 PM]

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Actually, NeHe''s method, unlike your second one, is cross-platform, since it doesn''t assume anything about the endianness of the target platform.


How appropriate. You fight like a cow.

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