Re: flood fill

[John Cupitt ng-london org uk]

You can fetch the bitmap from the server with gdk_image_get(), or fetch a
particular pixel with gdk_image_get_pixel(). 

This is probably not a good solution though :-( it will be slow, it will not
work with half-obscured windows (you'd need to draw to an off-screen window
to avoid that), and the pixels you get back are rather close to the hardware
and difficult to reconstruct RGB from.

You might be better off integrating your flood-fill into a client-side
graphics library. You'd at least have a good knowledge of the pixel layout.
Maybe something like libart?

  http://www.levien.com/libart/

I'm sure there are many more. If you just need line draw, you can write your
own system pretty easily.

John

Saul Simhon wrote:
> I wish I can use gdk_draw_polygon....However I need to plug in my own
custom
> flood fill algorithm. (its actually a texture synthesis method!)  I
> basically need to iterate thorough the pixel array and detect what color
the
> pixel is and decide weather to continue to fill or stop (hit a boundary).
> I'm just not sure how to detect the color of a pixel on a drawable widget?
> 
> Thanks,
> Saul.
> 
> 
>>>I'm trying to write a custom procedure that would flood fill an area
> 
> using a c
> 
>>>olor (or texture). I have used the drawing_area widget
>>>and drew an arbitrary closed polygon on it using the gdk_draw_line()
> 
> function
> 
>>>(black lines over a white background). All I need to do is fill in the
> 
> pixels
> 
>>>within the boundary. Does anyone know how I can get the boundary. (I
> 
> obviously
> 
>>>have the points of the polygon vertices, but I would need the scan-line
> 
> point
> 
>>>s generated from the draw_line function). Perhaps I can capture the color
> 
> at t
> 
>>>he (x,y) positions? anyone know how?
>>
>>gdk_draw_polygon ?
>>
>>--p
>>_______________________________________________
>>gtk-list mailing list
>>gtk-list gnome org
>>http://mail.gnome.org/mailman/.listinfo/gtk-list
>>
>>
> 
> 
> _______________________________________________
> gtk-list mailing list
> gtk-list gnome org
> http://mail.gnome.org/mailman/listinfo/gtk-list
> 




========================================================== 

Madame de Pompadour 
Images of a Mistress 

16 October 2002 - 12 January 2003 

For information and tickets: 
http://www.nationalgallery.org.uk/exhibitions/pompadour/default.htm