Render conformance

Peter Nilsson peter at
Wed Sep 15 04:37:28 PDT 2004

On Wed, 2004-09-15 at 14:04, Martijn Sipkema wrote:
> [...]
> Why do we actually use Render instead of just using OpenGL. Another
> API to learn and implement, not well documented, not cross-platform and
> hard to accelerate.

It is a general model, meaning it provides a standard way to create a
"rendering library" to an arbitrary devicem like in the Cairo library.
In this case OpenGL. Standards are good, as long as it doesn't pose a
threat to efficient use of the underlying mechanism. I think Render is
well designed to fit most such contexts, that I know of. The Render
model has, I think, been proven very efficient when implemented in
OpenGL, as of the Glitz library. 

> As for sub-pixel (as in per component) rendered graphics, I think that's a
> bad idea also. Now pixel data is display dependend and the abstraction of
> the ``picture element is essentially'' gone.

If you don't want it, don't use it :) There are several cases where I
have seen significant visual improvements from subpixel rendering. I
know I want it!

> [...]
> - create a single library/API for 2d poscript-like drawing (OpenVG?)

What, like Cairo?

> - use an auxiliary buffer to render a antialiased path without using
> multisampling, i.e. make sure most drivers can provide a configuration
> with an aux buffer.

Have a look at how Glitz does the davidr-style AA :), when multisample
is missing. Performance and visual output is impressive. 

Peter N
> --ms
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