Odd problem with DXTBmp

Thanks, Stefan. I'm not sure what happened. I think neglecting to install the DLL's set off a chain reaction. When I couldn't get a decent alpha, I started playing with the default "save as" feature in MSPaint, GIMP, and Paint.net, and things went downhill from there. EMatheson's suggestion about unchecking "Write Color Space Information" fixed the weird offset in GIMP, and the DLL's apparently fixed the lightness/darkness issues with the alphas. I just had to let the editing programs save the images with just the "save" button (24-bit by default) instead of "save as" (16-color, 256-color, 24-bit, 32-bit). If I'd paid attention to Martin Wright's instructions, I wouldn't have created such a mess. Thankfully it's fixed. Thanks, everybody.

Pat
 
Just a comment, FWIW. There is a school of thought which says Never do your edits from within DXTBMP using re-import (because of degradation issues, which you will notice quickly whenever you iterate the above process). Rather, do your layered editing within your paint program, keeping the layered files at all times. Save a copy as 24 bit BMP. Also from within your paint prog, create an alpha channel as a separate file, call it, for conveniece, filename_a.bmp. NOW load DXTBMP, load the 24 bit RGB BMP, then add the alpha file, then save in the FS format you need. Done. Any changes: go back to your layered original files.
 
mjahn said:
Just a comment, FWIW. There is a school of thought which says Never do your edits from within DXTBMP using re-import (because of degradation issues, which you will notice quickly whenever you iterate the above process). Rather, do your layered editing within your paint program, keeping the layered files at all times. Save a copy as 24 bit BMP. Also from within your paint prog, create an alpha channel as a separate file, call it, for conveniece, filename_a.bmp. NOW load DXTBMP, load the 24 bit RGB BMP, then add the alpha file, then save in the FS format you need. Done. Any changes: go back to your layered original files.
Click to expand...

Thanks, Manfred. More good ideas, I'm sad that I waited so many years before I started posting around here. I have noticed the degradation at times. One thing that's always bugged me: if I'm saving the texture as 32-bit 888-8, won't there be some degradation by loading a 24-bit image?

Pat
 
patful said:
One thing that's always bugged me: if I'm saving the texture as 32-bit 888-8, won't there be some degradation by loading a 24-bit image?
Click to expand...

No; because 32 bit 888-8 is nothing but 24bit RGB (=R8+G8+B8=24) plus alpha (another 8 = 32). 32 bit does not suffer degradation, dxt3 does, in addition to having a lesser resolution alpha, that's why people prefer 32 bit especially when the alpha is crucial for reflection effects etc. Of course, texture size and loading times may be important, too, dxt3 is better there.
 
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