We still need to handle the repeat modes
Add support for offsetting the texture shader

Basically whenever we render a path with a fill/stroke renderer
for an area A. We allocate a texture of size A.wh and use the
tex coords to match such texture. In case the desired area A is not
of the size and offset of the whole target surface, we need to match
the input texture coordinates for area A to the texture of size A in
the 0,0 -> A.w, A.h range
Add the restrict and pad repeat modes