| Re: [AD] Font drawing bug |
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On Fri, Aug 8, 2008 at 3:03 PM, Trent Gamblin <trent@xxxxxxxxxx> wrote:
> On Fri, August 8, 2008 4:22 am, Peter Hull said:
> What do you mean by "blanked"? Presently all bitmaps have their data
> set to 0s unless the driver creates the bitmap memory itself. So I
> think the answer is, yes, they should all be blanked.
The OpenGL bitmaps allocate a block of system memory which is set to
0, but the GL texture is not. When the bitmap is the target of a blit,
the texture is copied to RAM, modified and copied back. I think that
OpenGL does not say anything about the content of an allocated
texture, does it?
Milan's point is the key IMO:
"Why is the input blended and not just written over the garbage in the
first place?"
Shouldn't we set up the blender to do a straight copy instead of clear
+ translucent blit?
Pete