[cairo] Options for disabling antialiasing

[Carl Worth]

On Fri, 15 Oct 2004 23:58:19 -0400, "Robert O'Callahan" wrote:
> Not speaking for Ravindra, but one thing I can think of is performance. 
> Making Cairo *the* graphics substrate for Mozilla will be a no-brainer 
> for us only if we have a Cairo backend as fast as Win32 GDI on low-end 
> systems --- at least for the simple stuff that we need to render HTML, 
> i.e. mostly just text, images and rectangles. It might be easier to 
> reach that goal if we avoid antialiasing the rectangles.

I'd rather try to get high performance without sacrificing rendering
quality. There's still lots of room for optimizations within cairo,
(even ignoring things like glitz that are already very fast given the
right hardware). I think effort would be better spent speeding up the
rendering pipeline we have already rather than inventing a new
non-antialiased version.

As far as "draw a simple, pixel-aligned rectangle--no antialiasing
necessary", it should be a fairly simple matter to make code like the
following:

	cairo_rectangle (cr, x, y, width, height);
	cairo_fill (cr);

To make code like this trigger a very fast path in the implementation.
I'm much more interested in targeted optimizations for cases like this
rather than changing the rendering model with something like a
"disable-antialiasing" switch.

-Carl