Current vector drawing requires several methods for compositing,
it's shouldnt have only masking but other blending functions
such as matte in lottie, porter&duff in android, etc.
Previously we didn't specify this method name,
just reserved the options and now we started to define the methods
with ector_renderer_composite_method() instead of mask_set().
Previous masking image is generated on vg rendering time,
though context is changed to main vg rendering to masking,
This had a issue that ector context switching which is not allowed
in software backend because of asynchronou method.
Now, this improvment brings the masking rendering move to
vg render pre step with synchronous rendering method,
then use the masking surface in the main vg rendering.
Dectected huge amount of unnecessray internal events triggering
which were signaled via vg nodes.
By events, nodes were connected with each others,
and finally reaches to vg object to update its rendering properly.
However GFX_PATH_CHANGE signal is too commonly triggered for scenarios,
listening and response it is too burdensome.
We acutally don't need to do this if all nodes could share the
vg object. Nodes directly notify vg object to update it.
Next patch will come to remove stupid GFX_PATH_CHANGE that's aweful
in performance wise.
This implementation uses Ector_Buffer to generate mask image from vg container,
and pass it to Ector engine. Ector renderer could blend this image as a mask.
Yet only vg container works as a mask, we could extend shape to support masking later.
Still vector gl drawing is not completed, We use software ector buffer to draw on it.
This is on progessing.
Hermet Park