One problem is, that tolua/lua does not handle plain data pointers
properly. Therefore something like
local surface = cairo_image_surface_create_for_data(
imlib_image_get_data_for_reading_only(), ..
will fail using the lua bindings. Hence this wrapper, which adds
a function which be used to draw an imlib image to a cairo surface.
This also addresses another issue, drawing images with a transparent
background (e.g. gifs or pngs) to the cairo surface properly. Apparently
the image format of imlib is incompatible to cairos which uses
pre-multiplied data. This is also explained in the cairo documentation.
A fix for this issue is to blend the image with another alpha mask to
get the correct values. The code and explanation for this was taken from
http://lists.cairographics.org/archives/cairo/2008-March/013492.html
Executive Summary: This wrapper function can load (transparent) images
(e.g. gif or png) from a file by using imlib and draw them on a cairo
surface.
This wrapper functions should facilitate the handling of rsvg handles.
Especially unrefing with g_object_unref does not seem to work properly
using the lua bindings.
Add scratch files as a start: merge rsvg.h and rsvg-cairo.h.
Concatenate licenses of rsvg.h and rsvg-cairo.
Remove unnecessary defines, private structs, unused apis
(GIO/GdkPixbuf), etc.
Replace deprecated api functions with glib-object functions
Add headers for glib.h and librsvg/rsvg.h
Improved Lua API (lua_read_parse has been removed in favour of the
conky_parse() Lua API call). The docs have been improved to reflect the
recent Lua API stuff as well. Introduced new Lua Cairo and Imlib2
bindings, which require the tolua++ tool. Fixed some other
miscellaneous doc related things.
