[vwnc] Cairo alpha value on arcs and circles

Hi,
I am making a lot of progress using Cairo, however arcs and circles do
not maintain the aplha values of colors and paterns
and I don't have the same problem with rectangles.

Is there any workaround for this ?

Regards,

@+Maarten,

 

_______________________________________________
vwnc mailing list
[hidden email]
http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

On Jun 1, 2008, at 2:21 PM, Maarten Mostert wrote:

> Hi,
> I am making a lot of progress using Cairo, however arcs and circles do
> not maintain the aplha values of colors and paterns
> and I don't have the same problem with rectangles.
>
> Is there any workaround for this ?

Maarten,

Glad to hear Cairo is working well for you. :)

Can you please provide a little more info about what you're seeing?  
What platform you're running on. Three things that would be nice to  
know:
1) What platform are you running on?
2) What's the result of the following expression:
CairoGraphics.LibCairo libraryVersion
3) Can you provide a simple test case? Maybe a code snippet that does  
something like:
window := ApplicationWindow new.
window component: Panel new.
window open.
window component
        add:
                (VisualBlock
                        block:
                                [:gc :box |
                                gc
                                        newCairoContextWhile:
                                                [:cr |
                                                "your sample code here"
                                                ]])

--
Travis Griggs
Objologist
My Other Machine runs OSX. But then... so does this one.


_______________________________________________
vwnc mailing list
[hidden email]
http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

Hi Travis,

I am running on OSX Leopard through the X11 VM (I did not manage to get Cairo running under Quartz even if specified explicitely it keeps on missing libraries ?).

This is what I see:




I now also run my code on XP where it draws correctly next to the old graphics context.




CairoGraphics.LibCairo libraryVersion = 1.6.4    (both OSX/X11 and XP)

The test case is very simple just have a look at Akamura which states:

Things >> renderOn: aCR
    aCR
        sourceRed: 1
            green: 0
            blue: 0
            alpha: 0.4;
        circleCenter: position radius: 4;
        fillPreserve;
        sourceRed: 0.8
            green: 0
            blue: 0
            alpha: 0.8;
        strokeWidth: 1;
        stroke

Notice that Akamura will draw you plain circles except if you drag them quickly ?

By the way for debugging I allways use renderOn: instead of newCairoContextWhile:  and X11 never gives any checkStatus error ! You cannot say that for XP !


I keep on having problems working with Visualworks and my MacBook though, the OSX X11 vm keeps on putting popup menus everewhere except where you expect them. The normal vm doesn't do Cairo and I don't manage to find the keys for square backets or the vertical bar on my french keyboard when running Vista  with Bootcamp ?? Any ideas :-P


Regards,

@+Maarten,


Travis Griggs a écrit :

On Jun 1, 2008, at 2:21 PM, Maarten Mostert wrote:

Hi,
I am making a lot of progress using Cairo, however arcs and circles do
not maintain the aplha values of colors and paterns
and I don't have the same problem with rectangles.

Is there any workaround for this ?

Maarten,

Glad to hear Cairo is working well for you. :)

Can you please provide a little more info about what you're seeing? What platform you're running on. Three things that would be nice to know:
1) What platform are you running on?
2) What's the result of the following expression:
CairoGraphics.LibCairo libraryVersion
3) Can you provide a simple test case? Maybe a code snippet that does something like:
window := ApplicationWindow new.
window component: Panel new.
window open.
window component
    add:
        (VisualBlock
            block:
                [:gc :box |
                gc
                    newCairoContextWhile:
                        [:cr |
                        "your sample code here"
                        ]])

--
Travis Griggs
Objologist
My Other Machine runs OSX. But then... so does this one.

_______________________________________________
vwnc mailing list
[hidden email]
http://lists.cs.uiuc.edu/mailman/listinfo/vwnc