Keith Packard <[EMAIL PROTECTED]> wrote: > > So fast, efficient text could be done in XFree86 if a single function was > > used to transfer an entire bitmap in the driver code (pre-clipping could > > easily be done before the driver code is called), and some high level > > code to maintain and render the glyphs into the pre-allocated large > > bitmap. > > That's how Render does text today, except that it allocates the > temporary bitmap on the fly (which isn't a big deal with modern > malloc implementations). Monochrome bitmaps the size of the > screen are one thing, but 32bpp bitmaps at screen size are a bit > large to keep around for this purpose (yes, Render glyphs really > are 32bpp on LCD screens).
Right, but I wasn't talking about RENDER in this case but the standard case of aliased text. Then again I imagine if there is a choice between aliased and anti-aliased text, no-one would want the aliased version anymore so performance is not important ;-) And yes, 32bpp bitmaps would be a little too large to keep around. Besides, the primary reason to keep large mono bitmaps around is because it makes it easier to render the text due to the packed bits in mono bitmaps. 32bpp is much easier to handle with bitmaps just the size of the text due to one pixel per DWORD ;-) > > Granted, if you have hardware alpha blits that will be the fastest way to > > do this. But if you don't have hardware alpha blits (and lots of cards > > supported by XFree86 do not), you can still speed up anti-aliased text > > quite a lot by using a 4 or 8 level scheme using multiple mono bitmaps. > > I suppose, but it wouldn't be compatible with the Render > semantics. If I'd heard users complaining about text performance, > I'd be more interested. Plus, the number of users with cards that > can't support image compositing is rapidly declining; essentially > any card that has even the smallest amount of acceleration for 3D > graphics can accelerate Render. Very true, but if you consider the fact that right now there is only one graphics driver in XFree86 that actually has the composting functions enabled (excluding closed NVIDIA drivers), the multi-level scheme could accelerate anti-aliased text on a lot of hardware instantly. Then when people get the time, the composting functions could be implemented to make it better and faster where applicable. Regards, --- Kendall Bennett Chief Executive Officer SciTech Software, Inc. Phone: (530) 894 8400 http://www.scitechsoft.com ~ SciTech SNAP - The future of device driver technology! ~ _______________________________________________ Devel mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/devel
