GTK+ to Use Cairo Vector Engine

Eugenia writes "GTK+ is now the first major toolkit to have added support for the Cairo 2D vector graphics library, which is designed to provide high-quality display and print output. GTK+ project leader Owen Taylor has commented on the X/GTK integration of Cairo. To put it in perspective, Cairo is similar to OSX's Quartz engine and Longhorn's Avalon (PPT analysis). The 3D hardware accelerated image compositing OpenGL part of Cairo will be provided by the Glitz library. Cairo is 'possible' to be part of Qt 4.x at a later date, according to Trolltech's Qt 4 technical preview document."

Comments

Re:Why give up bitmaps

[Rolman]

A vector engine is not always a size-to-performance tradeoff.

1) Smaller sizes also give a performance boost on all types of data transfer, including expensive memory bandwidth
2) The rasterized vectors can still be cached, this reduces overhead during redrawing operations (something already being done with bitmaps)
3) Vectors give you resolution-independent displays that have better visual quality at negligible performance differences between resolutions (this is debatable, but I'm talking about full hardware-acceleration)
4) Cairo, Quartz and Avalon are ultimately designed for GPU acceleration, so ideally there won't be a performance hit on the CPU

Yes, you may still need a somewhat powerful PC to have full-access to all the benefits of these vector-based engines, but on less powerful equipment you can do something you can't do with bitmaps, and that's having a smoother and more graceful visual degradation using the same source material.

And, by the way, we'll still be using bitmaps for a long time, so you don't need to worry about GTK/X developers deprecating bitmap rendering and everything becoming vectors overnight, chances are that most users will need to have some form of programmable GPU before that happens. I guess that's why Avalon is getting delay after delay, and Apple can get away with it so much earlier because it has better control on its out-of-the-box hardware capabilities.

Re:Vector Graphics is a DUPE of the NeXT box...

[TheRaven64]

I was never much of a PS hacker, but I understand that PS can do a lot more than graphics work.

PostScript is a Turing-Complete language. This actually makes it a bad choice for interactive graphics (i.e. not printing), because it is impossible to determine how long a piece of PS code will take to run in advance (or even if it will ever terminate - see the halting problem). Display PDF, used in Quartz, eliminates this problem, since PDF is a non-Turing-Complete subset of PS.

I own a NeXT cube system (currently in my attic, unused)

I don't suppose you're interested in selling it are you?

Mathematics

[lisaparratt]

I looked at Cairo because it purported to be fixed point, which would have made it ideal for many embedded consumer products (which rarely have FPUs), and enabled them to have pretty OS X style graphics.

I was most disappointed when I found out it was only the API that was fixed point, and most of the internals used floating point.

Re:Open Source 3D

[Rutulian]

I'm surprised nobody has mentioned the Open Graphics Project in this thread. With any luck the card will be released just in time for Cairo to take advantage of it.