java-gnome-hackers

[java-gnome-hackers] Progress on 'cairo' branch

[Andrew C. <an...@op...>]

Srichand,

I spent the afternoon cleaning up the patches I had lying about on the
'cairo' branch and committing them.

What I'd been working on when I last hacked on this was working out what
internals would be necessary to make the Plumbing.proxyFor() equivalent
work for the Cairo types.

With Surface and now Pattern we've got concrete subtypes for each of the
various cairo_surface_t and now cairo_pattern_t that you can have. The
trick is that there's no g_type_name() equivalent to figure out the type
for an arbitrary pointer, so we have to do a bit of switching Java side
to figure out which of the base Cairo types it is, then hand off to the
C side to do a switch over the various type constants to finally know
which Class to actually instantiate. Luckily I think we know enough
between generation (for the resultant Class constant being requested in
entityFor()) at runtime (the various _get_type() functions to make the
right calls.

After doing all that for Pattern and being fairly satisfied with it, I
attempted to start testing it only to not be able to find a Cairo
function that returns a cairo_pattern_t that's not a constructor [If
someone can suggest one, I'd be grateful] so I couldn't actually write a
test to exercise this code. Grumble.

Nevertheless, the real point of the work was to figure out the design
pattern that would be used for getting Proxies for arbitrary pointers in
the Cairo library, and I think that's more or less sorted. Let me know
what you think as you poke away at whichever bit of Cairo interested
you.

AfC
Bangalore

Re: [java-gnome-hackers] Progress on 'cairo' branch

[Behdad E. <be...@be...>]

On Sun, 2007-12-09 at 17:58 +0530, Andrew Cowie wrote:
> 
> After doing all that for Pattern and being fairly satisfied with it, I
> attempted to start testing it only to not be able to find a Cairo
> function that returns a cairo_pattern_t that's not a constructor [If
> someone can suggest one, I'd be grateful] so I couldn't actually write
> a test to exercise this code. Grumble.

cairo_get_source().

-- 
behdad
http://behdad.org/

...very few phenomena can pull someone out of Deep Hack Mode, with two
noted exceptions: being struck by lightning, or worse, your *computer*
being struck by lightning.  -- Matt Welsh

Re: [java-gnome-hackers] Progress on 'cairo' branch

[Andrew C. <an...@op...>]

On Sun, 2007-12-09 at 15:03 -0500, Behdad Esfahbod wrote:
> On Sun, 2007-12-09 at 17:58 +0530, Andrew Cowie wrote:
> >=20
> > After doing all that for Pattern and being fairly satisfied with it, I
> > attempted to start testing it only to not be able to find a Cairo
> > function that returns a cairo_pattern_t that's not a constructor [If
> > someone can suggest one, I'd be grateful] so I couldn't actually write
> > a test to exercise this code. Grumble.
>=20
> cairo_get_source().

Thanks Behdad! I specifically needed something that would fetch a native
entity that had not been explicitly instantiated on the Java side, and

    Context cr;
    ImageSurface s;
    Pattern p;

    s =3D new ImageSurface(Format.ARGB32, 100, 100);
    cr =3D new Context(s);
    cr.setSourceRGBA(0.0, 0.0, 1.0, 1.0);

    p =3D cr.getSource();

was a perfect example to use in a unit test validating the code paths
for Pattern. Cheers,

AfC
Sydney