Posted by Kevin Matthews on May 05, 1997 at 14:59:43:
In Reply to: Graphics Acceleration Card posted by J. Rolando Sanchez on May 05, 1997 at 14:57:41:
We've done some preliminary testing with the Newer board, and I believe it falls prey to a problem that makes all of the higher priced QD3D boards bogus, at least until QD3D 1.6 is released.
In QD3D 1.5, in addition to many crucial improvements, Apple made some internal changes to QuickDraw 3D geometry that are really horrible. There's a very primitive new geometry called a "Trimesh". This geometry is very easy to accelerate, but it is almost useless for creating intelligent model structures, like those inside DesignWorkshop. In DesignWorkshop we use the QD3D Mesh data structure, which is excellent for modeling purposes.
The shocking thing that Apple did, perhaps to allow the accelerator board makers to score better in some meaningless benchmarks somewhere, was to drop the already excellent direct rendering functions for mesh geometry, and intead, internally convert all meshes into trimeshes.
What this means is that every time a model redraws in QD3D, all the meshes are reconverted into trimeshes, and then the rendering of the trimeshes is accelerated. The overall performance is much worse than with QD3D 1.0.6, where meshes were accelerated directly.
Apple has promised to fix this in QD3D 1.6, which is the next update planned for fairly soon. They've specifically told us that we should not abandon the mesh geometry, and that their mesh perfromance problem will be fixed. Artifice does have a decent backup plan if Apple doesn't come through on this, but we'd rather spend our energy improving DW than covering for the mother ship.
So right now it's not worth it to get an expensive board to accelerate any QD3D application that uses meshes. But I still think the lower priced boards like those from Apple and ATI are well worth it.
The ATI boards are much improved recentl, by the way, becuase they have updated their driver software.