Re: Release of gui libraries

[Willem Rein Oudshoorn]

Charles Philip Chan <karnak@look.ca> writes:
> and here is the backtrace:
> 
> (gdb) backtrace
> #0  0x408cf437 in _pixmap_combine_alpha (context=0x824aba8, 
>     source_im=0x8451dd0, source_alpha=0x8502df8, dest_im=0x82fef78, 
>     dest_alpha=0x8502e18, srect={x = 0, y = 0, width = 253, height = 188}, 
>     op=NSCompositeSourceOver, drawMechanism=XGDM_FAST32, fraction=1)
>     at XGBitmap.m:153
> #1  0x408e15cf in
>     _i_XGGState___compositeGState_fromRect_toPoint_op_fraction_ (   
>     self=0x82fddf8, _cmd=0x409143b0, source=0x82fe9d8, fromRect={origin = {   
>  
>     x = 0, y = 0}, size = {width = 253, height = 187.942856}}, toPoint={    
>     x = 2, y = 23.5285721}, op=NSCompositeSourceOver, delta=1)    at
>     XGGState.m:599
[Note the above is reformatted and abbreviated]

Ok, I this bug is most probably caused by the fact that the 
height is rounded up from 187.942856 --> 188.
The following patch will always round the size of the 
rectangle down.  So, if you can reproduce the crash, could
you check if this patch fixes it?

DISCLAIMER:  I have not been able to reproduce this crash,
also, changing this rounding code might introduce 
some problems in other circumstances.  
But the rounding issue is actually not dealt with at all
in a satisfactory way.  The rounding functions that are
now in place are an attempt to make the rounding more explicit.
So basically, when you deal with non-integer coordinates
it might not work.  

Initial testing by my does not show any problems with 
this patch.  But it should be tested.


2002-01-26  Willem Rein Oudshoorn  <woudshoo@xs4all.nl>

        * xgps/Headers/gnustep/xgps/XGGeometry.h (XGWindowRectToX): simpler 
algorithme
        for determining size result.  This one is stable with respect to the 
origin.
        added explanation in comment.

xgg2.diff
Description: fix conversion from OS --> X coordinates