[gs-cvs] rev 7936 - trunk/gs/src

[Igor V. Melichev]

The log message for revision 7936 has been changed like this :



Fix (shadings) : The decomposition limit must depend on resolution.

DETAILS : 

This partially improves performance for the test case of 
the bug 689189 "PDF fails with /unregistered in --shfill--".

The old code limits the decomposition of a shading with 1 pixel.
It gives a good precision for low resolution devices,
such as display with 72dpi. However for high resolution devices the
decomposition limit may be bigger, because tinny parts are not visible.
Now we make it be dependent on the device resolution.
It speeds up the high resolution rendering with quickly varying colors.
The worker formula is :

 decomposition_limit = float2fixed(HWResolution / 72)

With 300 dpi the file "self-intersect2.ps" renders a few worse 
near the self-intersection. It may be visible when viewing the 
ppmraw output with a monitor. We think it's a reasonable tradeof
for the performance. Actually the monitor performs 
a significant zoom when viewing "actual pixels",
because the monitor's resolution is much smaller.
The quality degradation shouldn't be visible with a 300 dpi printer.

EXPECTED DIFFERENCES :

Minor difference in colors with most shadings :

"442-01.ps" 
"446-01-fixed.ps" 
"464-01-fixed.ps" 
"478-01.ps" 
"483-01.ps" 
"483-05-fixed.ps" 
"BEST8-99-Path.fh7.pdf" 
"Bug688631.pdf" 
"chilis_black.pdf" 
"Clarke Tate Manns Chinese.ai" 
"gradmesh.ai" 
"Openhuis_pdf_zw.pdf" 
"self-intersect2.ps" 
"SmoothShading.pdf" 
"self-intersect2.ps" 
"SmoothShading.pdf" 
"STEUER-RollingMesh 1(linear).ai" 
"STEUER-RollingMesh 2(radial).ai" 
"STEUER-RollingMesh 3(Final).ai" 
"Testform.v1.0.2.pdf"