[news.eclipse.gef3d] Re: A couple of errors in ..draw3d

[Kristian Duske <kristian.duske@xxxxxxxxxxxxxxxx>]

Hi again,

I just implemented some of the missing advanced graphics functions on 
DummyGraphics, LogGraphics and LwjglGraphics. The remaining 
unimplemented functions are

Graphics#drawPath(org.eclipse.swt.graphics.Path)
Graphics#drawText(String, org.eclipse.draw2d.geometry.Point, int)
Graphics#drawText(String, int, int, int)
Graphics#drawTextLayout(org.eclipse.swt.graphics.TextLayout, int, int)
Graphics#drawTextLayout(org.eclipse.swt.graphics.TextLayout, int, int, int,
	int, Color, Color)
Graphics#fillPath(org.eclipse.swt.graphics.Path)
Graphics#setClip(org.eclipse.swt.graphics.Path)

These functions make use of platform dependent resources (Path, 
TextLayout, Pattern) and are not trivial to implement. I am not sure if 
it is possible at all to implement this functionality without changing 
the clients of Graphics as well, because I don't see how I can access 
the information contained in the platform dependent resources in a 
platform independent way.

The only way I see right now would be to subclass Path, TextLayout and 
Pattern and write implementations that can use GL to emulate this 
functionality, but as I stated above, this would require modifying 
client code. Another way would be to get the SWT team interested in 
GLGraphics and add GL implementations of those classes to SWT directly. 
But even then, I'd have to implement a lot of this functionality by 
hand. For example, GL doesn't support paths as clipping regions (only 
planes can be used and paths can contain arcs and curves) - I'd have to 
write the clipping code for clipping paths by hand.

I hope for now that no existing GEF editor uses these features so that 
we won't need to implement them for a while.

Best regards
Kristian