Re: Good gtk object to make a captcha

[David Nečas (Yeti) <yeti physics muni cz>]

On Mon, Jul 23, 2007 at 10:50:27PM +0200, Tony B wrote:
> I'm working in the idea to make a captcha (system generating picts
> containing text you should type to prove you're not a bot...) using GTK+ 2

Why on Earth?

> and I'm seeking the right object to create an image from scratch and then
> saving it in a file.

Then look elsewhere.

> I had a look in the tutorial and in the ref manual and 3 objects seems to be
> ok: gtk drawing_area, gtk_image, and Gdk Pixbuf.

GtkDrawingArea and GtkImage are *widgets* displayed *on*
*screen*.

GdkPixbuf is a raw pixel buffer with essentially zero
drawing functions available.

> I don't know really how I should make the choice (and I may forget another
> object I didn't see...).

So, neither is what you want.

> What I have to do with the object is:
>  * creating a pict with an uniform background
>  * having the ability to do standard operations (points, polygons, etc...)
>  * having the ability to read a pixel
>  * having the ability to display text with a choosen font and size
>  * being able to save the final image...
>  * the rest to produce a good (I hope) captcha would be my work...
> 
> Has anybody any reasons for a choice or a pointer to relevant docs to make
> the choice?

Relevant docs are for instance:

  http://www.imagemagick.org/script/api.php
  http://www.libgd.org/Main_Page
  http://cairographics.org/
  and others

Yeti

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