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yjh1982
11-18-2004, 02:55 PM
I have a qustion let me uptight.
I query the glu edition on nvidia card (gf440&fx5200) and found is microsoft edition.
:eek:
Is mean glu not be accelerated by card?
but I use gluSphere and gluDisk the slices is
differ--nvidia card always smooth and microsoft
soft implementation be affect by slices ...

and if glu function really not be accelerated .
is only microsoft platform,or also other platform(mac,linux...) ??

Humus
11-18-2004, 03:24 PM
glu is a library layered on top of OpenGL. It's not provided by the driver.

yjh1982
11-18-2004, 03:40 PM
but Why use gluSphere and gluDisk the slices on nvidia card always smooth and on microsoft
soft implementation be affect by slices ...?

and I believe modern card can implement
gluDisk's function.isn't it?

jwatte
11-19-2004, 06:32 PM
gluDisk() generates a specific vertex array, according to its quadratic argument. The graphics card then accelerates the actual rendering of that vertex array.

Graphics cards, generally, cannot accelerate primitives like "spheres" or "disks" or "quadrics" -- they accelerate triangle lists, and oftentimes lines and points. They "accelerate" convex polygons, insofar as a polygon equals a triangle fan, which is a special case of a triangle list.

yjh1982
11-21-2004, 02:56 PM
Originally posted by jwatte:
gluDisk() generates a specific vertex array, according to its quadratic argument. The graphics card then accelerates the actual rendering of that vertex array.
I mean is:
If not be accelerated(gl and glu edition are all microsoft's,a very badly card in the mainboard ),
slices too low the gluDisk like a polygon .

but be accelerated on ATI or nvidia card of 3d accelerated.slices will almostly no affect on
gluDisk--is always so smooth.

what trick in it?