Re: [gef-dev] Ghost shape, Mac OS X xor issue, and a possible solution

[Jens v.P. <developer@xxxxxxxxx>]

Hi,

Am 15.11.2005 um 17:25 schrieb Randy Hudson:

> Besides requiring GDI+ library on windows 2000, and Cairo on Linux,  
> painting using alpha is probably 1-2 orders of magnitude slower  
> than XOR.  Any change we make should probably be OS-specific.

Maybe I've got something wrong here. But: (SWT) XOR functionality  
_is_ deprecated! It's deprecated since it is platform specific. It is  
not (and will never be) working on Mac OS X. Mac OS X is listed as  
one of the reference platforms in the Eclipse 3.1.1 release notes. Of  
course, this seems to be a SWT problem in first place. Or a OS X  
problem. I don't know. But anyway: SWT setAlpha is not deprecated.

Maybe my quick hack can be made OS-specific:

private static boolean bAlphaGhost = SWT.getPlatform().equals("carbon");

public static Shape makeGhostShape(Shape s) {
	s.setBackgroundColor(ghostFillColor);
	if (bAlphaGhost) {
		s.setAlpha(100);
	} else {
		s.setFillXOR(true);
		s.setOutlineXOR(true);
	}
	return s;
}

I don't like this sine I don't like these platform specific  
statements in Java.

I'm a feeling little bit like a Don Quichotte fighting against  
windmills. The performance of GEF under OS X is so bad, that I'm  
wondering if anyone is actually using GEF/OS X. I've tested GEF on  
several Macs, and even with a PowerMac 2 GHz Dual Core moving figures  
around feels like working with a 100 MHz Pentium. So, probably nobody  
will notice the bad ghost shape behaviour in OS X, since nobody is  
really using this combination :( Since GEF is running perfectly well  
under Windows, I assume SWT is the problem, but especially GEF is  
suffering from the bad SWT-OSX performance. It's a pity, since Cocoa/ 
Quarz is so fast -- e.g. dragging an image from Safari is amazing  
(the whole image, a little bit transparent, is moved) , too bad that  
GEF can't compete against this.

Jens