Re: First time pygoocanvas user

Le mardi 15 septembre 2009 à 19:07 -0500, Nick Peters a écrit :
> Hello,
> I have been developing an application that is basically a glorified
> paint program, allowing the user to draw a few shapes with the mouse (as
> well as lines). For a few days i have been stumped on how to get an
> "eraser" tool to work. I assume that it would be much like the drawing
> tools, only triggered when the mouse hits an item that the user has
> drawn using the enter_notify_event when the user has the eraser tool
> selected.
> I am however having a hard time, figuring out how to modify the item the
> mouse comes into contact with. I know how to setup the event, but i am
> unsure on what to edit or how to go about doing it. The pygoocanvas
> examples that i have looked at, mostly deal with pure drawing, and
> nothing to do with "erasing" part of an item (if there is an example,
> please say so and i can go out on the net and read about it). I have
> also had no luck with google searches on the subject.
> Has anybody on the list have experience in doing such an operation with
> pygoocanvas? Am i going about it in the wrong way? Any suggestions would
> be great!


You van check GCompris in it's gcomprixogoo development branch [1].
There is a drawing and animation tool based on goocanvas under

By the way it seems like you are confusing vector drawing and bitmap

In vector drawing like goocanvas is good at, you keep a list of shapes
like ellipse, rectangles and their properties like color, gradiant, ....
You can at any time edit shapes, moves them change their properties and
their z-axis (in front / on the back).

In bitmap drawing, you keep a list of pixels, and their colors. You
cannot manipulate the shapes once they have been painted on the



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