the dw, dh had a reason:
l,t and h,w define the rect on the image you want to draw.
x,y defines the position for the rect
dw,dh define the size of the image when you draw it.
The reason I added those: What if you have a 512x512 image you split up to 128x128 subimages. But for some reason you want to draw them in 80x60 or something similar? Without dw and dh, you can't do that. That's why I added them. If you want to draw it in 1:1 scale, you can still set w,h and dw,dh to the same value.
And the power of two: why should this be of interest? You don't need power of two if you draw subparts of a texture. There is no reason to enforce it. (the image will be as whole within VRAM and thus be power of 2 as it was loaded through BMs routines)
l,t and h,w define the rect on the image you want to draw.
x,y defines the position for the rect
dw,dh define the size of the image when you draw it.
The reason I added those: What if you have a 512x512 image you split up to 128x128 subimages. But for some reason you want to draw them in 80x60 or something similar? Without dw and dh, you can't do that. That's why I added them. If you want to draw it in 1:1 scale, you can still set w,h and dw,dh to the same value.
And the power of two: why should this be of interest? You don't need power of two if you draw subparts of a texture. There is no reason to enforce it. (the image will be as whole within VRAM and thus be power of 2 as it was loaded through BMs routines)