Optimisation for org.lwjgl.opengl.StateTracker

[Matthias]

The pushAttrib() and popAttrib() does a many calls to getCapabilities() to get the current StateTracker instance - this is unneccessary;

static void popAttrib() {
		StateTracker tracker = getStateTracker();
		if ((tracker.attrib_stack.popState() & GL11.GL_CLIENT_VERTEX_ARRAY_BIT) != 0) {
			tracker.vbo_array_stack.popState();
			tracker.vbo_element_stack.popState();
			tracker.pbo_pack_stack.popState();
			tracker.pbo_unpack_stack.popState();
			tracker.references_stack.popState();
		}
	}
	
	static void pushAttrib(int mask) {
		StateTracker tracker = getStateTracker();
		tracker.attrib_stack.pushState();
		tracker.attrib_stack.setState(mask);
		if ((mask & GL11.GL_CLIENT_VERTEX_ARRAY_BIT) != 0) {
			tracker.vbo_array_stack.pushState();
			tracker.vbo_element_stack.pushState();
			tracker.pbo_pack_stack.pushState();
			tracker.pbo_unpack_stack.pushState();
			tracker.references_stack.pushState();
		}
	}

	static StateTracker getStateTracker() {
		return GLContext.getCapabilities().tracker;
	}

This saves a lot work for code that is working with VBOs or VertexArrays.

[elias]

That's not the most up to date source code (are you using 0.99 source code or the CVS source?), but I've applied the gist of it to the subversion tree.

- elias