Pixilang v3.4.4

Pixilang updated to version 3.4.4!
What is new:

• additional (optional) parameters for the split_rgb() function: image_offset, channel_offset, size;
• additional (optional) parameters for the replace_values() function: dest_offset, src_offset, size;
• new file format: FORMAT_PIXICONTAINER (entire Pixilang container with properties, animation etc.);
• new container flags: GL_NO_XREPEAT, GL_NO_YREPEAT;
• new GIF export flags: GIF_GRAYSCALE, GIF_DITHER; see details in the examples/graphics/save_gif.pixi;
• new graphics examples: save_and_load_pixicontainer, replace_values;
• bugs fixed.