This add two new function that allows us to transform or project an
array of points instead of only transforming one point at a time. Recent
benchmarking has shown cogl_matrix_transform_point to be a bottleneck
sometimes, so this should allow us to reduce the overhead when
transforming lots of vertices at the same time, and also reduce the cost
of 3 component, non-projective transforms.
For now they are marked as experimental (you have to define
COGL_ENABLE_EXPERIMENTAL_API) because there is some concern that it
introduces some inconsistent naming. cogl_matrix_transform_point would
have to be renamed cogl_matrix_project_point to be consistent, but that
would be an API break.
e9e824fd86
