Re: [Pythoncard-users] [newbie] drawing over a bitmap

[Kevin A. <al...@se...>]

What you want to do is use the BitmapCanvas component to do your=20
drawing after you load your existing image. Both the loading and saving=20=

are shown in the doodle sample so I suggest basing your own application=20=

on the doodle sample. The saving is handled using a helper function=20
from the graphic module so you don't have to hardcode the wxWidgets=20
graphics filetype and a wxWidgets/wxPython method call:

from PythonCard import graphic # make sure you have this in your code
path =3D 'some.png' # your filename/path here
fileType =3D graphic.bitmapType(path)
bmp =3D self.components.bufOff.getBitmap() # change to whatever your=20
BitmapCanvas is named
bmp.SaveFile(path, fileType)

If you're really in a hurry, you can always just use the doodle sample=20=

to load an image, do your drawing in the shell window (start the=20
program with the -s command line option) and then use the File->Save=20
As... menu item.

ka

On Nov 29, 2005, at 8:13 AM, Mauro Cherubini wrote:

> Dear All,
>
> sorry for the newbie question but I am fighting with the following=20
> issue:
> I am trying to add some drawing on top of an existing bitmap.
> I tried two things: the first one was to draw directly on the image=20
> setting that as the working canvas (i.e., canvas =3D=20
> self.components.canvasBackground); the second was to draw on a=20
> separate canvas.
>
> The first attempt raised an exception because apparently is not=20
> possible to draw on bitmaps. The second attempt load the drawing=20
> canvas on top of the "background" bitmap and because it is not=20
> transparent it covers automatically the background.
>
> I tried to set the 'backgroundColor' to 'None' but without success (it=20=

> says that 'AttributeError: 'BitmapCanvas' object has no attribute=20
> 'backgroundColour'').
>
> Does anybody can help me to knock my head on the right place?
> Thanks in advance for the pain you will generously cause
>
>
> Mauro
>
>
> _______________
> Mauro Cherubini
> Research Associate
> Centre de Recherche et d'Appui pour la Formation et ses Technologies=20=

> (CRAFT) / Center for Research and Support of Training and its=20
> Technologies
>
> Ecole Polytechnique F=E9d=E9rale de Lausanne (EPFL) / Swiss Federal=20
> Institute of Technology Lausanne
> web: http://craft.epfl.ch -- blog:=20
> http://www.i-cherubini.it/mauro/blog/