When we build up a matrix from a series of operations, it's very useful
to know if the combined operations still result in something that matches
a wl_output_transform.
This adds a function to test if a matrix leads to a standard output
transform, and returns the transform if it does.
Tests are provided that check if complex series of operations return
expected results - the weston_matrix_needs_filtering function is tested
at the same time.
Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
If a transformation matrix causes a scale, a rotation not a multiple of 90
degrees or a non-integral translation then textures rendered with
it would benefit from bilinear filtering.
This test is done in a lazy fashion by examining elements of the matrix
to check for a simple pattern that indicates these conditions are met.
Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
This #define was used only by the matrix-test program, which was removed
in the previous commit.
Remove it as unused and fold away MATRIX_TEST_EXPORT.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
matrix.h is a public installed header and even used by libweston.h.
See "Rename compositor.h to libweston/libweston.h" for rationale.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
