Re: cairo: multiple sprites images in one PNG

[Lucas Levrel <llevrel yahoo fr>]

Le 15 mars 2012, Christopher Howard a écrit :

> Question for the veterans:
>
> ----------
> ship_surf = cairo_image_surface_create_from_png("ship.png");
> // ...
> cairo_set_source_surface (cr, ship_surf, x, y);
> cairo_paint (cr);
> ----------
>
> But what if I want, for ease of maintainability (and less system I/O
> calls) to put a whole bunch of sprites in one PNG? Is it possible for me
> to either...
>
> * load one PNG image into a surface, and then draw to a CR using only a
> small part of that surface?
>
> or
>
> * load one PNG into a surface, and then split that surface into multiple
> smaller surfaces?

I'm no veteran, but I'd create one small cairo_t per sprite, then repeat 
your last two lines above (where cr would be the sprite), once for each 
sprite, with appropriate x and y : Cairo will automatically clip what 
falls outside the sprite's cairo_t.

(Your first option seems feasible with clipping, but might be more 
complicated: you'd need to clip each time you draw the sprite.)

--
Lucas Levrel