Quartz2d vector images vs OpenGL vector description?

Question

How big of a difference is the description language of Quartz2d to OpenGL ES?

It seems they are similar in description power... except that Quartz is mostly 2d and that OpenGL is out of the box 3d ( but can be made 2d focused ).

Are the mappings from 2dQuartz to 2d OpenGL ES that different? Im sure there must be differences in some specific features that might be handled differently on one vs another... but to do a translator?

Anyone have experience with both OpenGL and Quartz2d have some insights?

Answer 1

Quartz and OpenGL ES are two completely different animals. While they both have a C-based API that deals with a state machine and that draws into a context, their purposes are dissimilar. In Quartz you specify lines, Bezier and quadratic curves, arcs, or rectangles, as well as fills, gradients, and shadows / glows. In OpenGL ES, you provide vertices, raster textures, and lighting information, from which a scene is generated.

They are both useful in particular cases. You might draw a 2-D static element using Quartz, into a view, layer, or texture, and then place and move that view or layer in 3-D space using Core Animation or do the same for a texture using OpenGL ES.

Rather than try to overlay one API on the other, use whichever is more appropriate for what you are doing, or look to a framework like cocos2d which lets you build and animate 2-D scenes or Core Animation where you can do Quartz drawing into a layer but still use a nicely abstracted API for moving these layers around.