Re: The big divide - graphics contexts and window servers

[Philippe C.D. Robert]

On Sun, 17 Mar 2002, Jeff Teunissen wrote:
<snip>
> > The only problem is that it doesn't natively handle fonts, which is
> > really important. There are libraries that add this capability to
> > OpenGL, but the best ones are written in C++, which means I'll have to
> > write some cumbersome wrappers (ok, NOW I want Objective-C++!).
> 
> It's not that OpenGL doesn't handle fonts -- it's that it doesn't handle text
> at all. This isn't a bad thing, you just have to _want_ to reinvent the wheel.

Not if you use an existing solution for that purpose...
 
> To get "fonts" in OpenGL, you draw them. Not a problem, but you need a font
> renderer to do it, and then you get to decide what resolution you want to
> upload it at, you get to upload the texture for each glyph (at whatever point
> size you want) and display it manually.

Well, there are libs which allow you to render True Type Fonts AFAIK.
 
> OpenGL is designed for 3D, and it's not happy with 2D. Most GL implementations
> don't accelerate 2D operations beyond throwing a quad on the screen, and some
> even leave it incomplete.

Uh? Where do you get that from? In GL there is no destinction between 2D and 
3D.Or do you mean imaging extensions? They are not part of core GL anway - 
which 
will change for 2.0 though.

> Also throw in the fact that on most non-professional implementations/cards,
> you can only have one direct-rendering window at a time.

I dunno about DRI or NVidias solutions for that, so if you know more ( as it 
seems ), please elaborate on that a little, I am very interested!...:-)

But you are right in that on other systems than Linux, GL acceleration is not 
handled very well ( AFAIK BSD for example ).

> For anything beyond games and professional or scientific graphics systems,
> OpenGL is rather a joke.

Uhm, why do you say so? Take Mac OS X, they use accelerated GL for Aqua more and
more - do you call that a joke?

> Oh...where'd you get the idea that OpenGL did antialiasing at all? It doesn't,
> that's beyond the scope of the specification.

No, but most graphics cards/GL drivers do handle anti aliasing.

-Phil
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