   Merging 2 textures
  Hi all:Sorry if my search-fu was not up to the challenge and someone can point to a prior thread.I'm trying to merge 2 textures into 1, and I've not been having much success.The hard parts:  The solution has to run on old hardware, so no framebuffers or other nice new toys.  The card seems to only have a front and back buffer.  The textures are NOT power of 2.    (so glCopyTexImage(GL_TEX_RECTANGLE_ARB,blah blah blah) generates GL_INVALID_ENUM).If anyone has suggestions (other than pouring a jerry can of gasoline on the machine and lighting it) for things I can try it would be greatly appreciated!Thanks.   
  Are the textures created by OpenGL or by your program?If they're created by your program, you could just combine them in your application, using array manipulation, and only pass the texture to OpenGL after it's already combined.   ;Quote:Original post by nagromoIf they're created by your program, you could just combine them in your application, using array manipulation, and only pass the texture to OpenGL after it's already combined.Copy that.Also, a note about NPOTD textures.Make sure using NPOTD is really required.When using NPOTD on old hardware you have two options:1- Resizing to POTD thuru interpolation: can sometime work just ok but often the result lacks in quality (especially at high-energy bounduaries) - the increased memory used is minor issue compared to this. The good thing is that the resulting texture is a first class citizen (so wrap modes and texture matrix tricks work ok).2- Padding (possibly with bordering). This yelds good results in terms of quality and can also have a good memory usage when multiple textures are involved. Unluckly, it'll break if you apply texture transformations or some wrapmode which involves repeating.;  Thanks.The reference docs seem to be down, and again, my search didn't turn up much...Is there an easy way to convert a texture to the power of 2 without stretching so that the new pixels/texels are blank??Is there a minimum size that that this sort of hardware will want to deal with?Thanks again.;Quote:Original post by emanon11Thanks.The reference docs seem to be down, and again, my search didn't turn up much...Is there an easy way to convert a texture to the power of 2 without stretching so that the new pixels/texels are blank??Is there a minimum size that that this sort of hardware will want to deal with?Thanks again.You mean scaling the image? Or like you said, stretching.There is gluScaleImage and also glhScaleImage from for glhlib library.Minimum size is always 1x1Maybe you want the maximum?int width_or_Height;glGetIntegerv(GL_MAX_TEXTURE_SIZE, &width_or_Height);That's for 1D and 2D texture.glGetIntegerv(GL_MAX_RECTANGLE_TEXTURE_SIZE_ARB, &width_or_Height);That's for RECT.;  the scaling functions stretch the image.I'm trying to not stretch it...essentially:/------------------\-----------|   orig image| delta|\------------------/ ||  invis delta h   | w    |\------------------------------/thksedit to fix text img   