[Xr] Help: Render error on XrFormatRGB32

Carl Worth cworth at east.isi.edu
Fri May 2 16:25:09 PDT 2003

On May 2, Soorya Kuloor wrote:
 > With all the fiddling stuff I am basically trying to get a trade off
 > between quality and rendering speed.

Ah, OK.

With the current implementation, changing from an 8-bit depth alpha
mask (antialiasing) to a 1-bit mask (no antialiasing) might save some
memory, but should not impact rendering speed. The same calculations
will be performed in both cases.

On the other hand, independent of the depth of the alpha buffer, you
can use the tolerance value to adjust a quality/speed tradeoff, (for
curve approximations anyway).

 > Another nice feature would be to provide options to use libic, even if
 > the X server contains Render extension.

It's possible to force libic rendering by using
XrSurfaceCreateForImage rather than

Though, for now, if you want to get the result to a drawable, (or to
some other non-X thingy), you'll have to do the XPutImage or
equivalent yourself.

And, I should mention that text support is totally broken right now
when using libic. (And it looks like XrShowImage is broken right now
in either libic or Render mode).


Carl Worth                                        
USC Information Sciences Institute                      cworth at isi.edu

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