On Fri, 2012-01-20 at 13:43 -0800, Josh Andler wrote:
Hey Tavmjong,
Thanks! I've been playing around (mostly today) and it seems that transparency is causing crashes very consistently for me. I was hoping to demo this over the weekend and stay up all night making a really intricate picture (transparency was needed for what I had in mind). I still plan to see what I can whip up later and will share the results, I just can't promise it will wow anyone. :)
Anyway, I just wanted to throw the backtrace your way and give you the steps to reproduce. This could very well be a cairo bug, but it looks to me more like it's in style handling on our end.
Step 1: Create mesh Step 2: Select mesh control/corner point Step 3: In F&S dialog try to modify Alpha value, it bounces right back to previous position Step 4: Try to modify Opacity value (either in F&S dialog or main window bottom status bar widget) Crash
Should be fixed now (modulo F&S alpha... see below).
Observation: In other gradient types it appears that in the F&S dialog does not keep Alpha/Opacity locked together even though they change the same value in a style (which is a complete assumption on my part). Note this is editing gradients stops/control points, not on an object proper. Whichever slider (Alpha or Opacity) that you use last sets the new alpha value and the other slider stays where it was. Either way, this seems like a bug in trunk afaict, I may be incorrect though.
Unlike an object than can have a separate fill opacity (i.e. alpha) and overall opacity (opacity slider), stops can only have one opacity. Whoever implemented stop opacity chose to only allow the opacity slider to change it. Since they are different for normal fill/stroke I don't think they should be the same for stops. The correct solution is probably to have the alpha slider grayed out when editing stop color.
Looking forward to your demo.
Tav