The compositor will likely do an order of magnitude less matrix
inversions than point transformations with an inverse, hence we do not
really need the optimised path for single-shot invert-and-transform.
Expose only the computing of the explicit inverse matrix in the API.
However, the matrix inversion tests need access to the internal
functions. Designate a unit test build by #defining UNIT_TEST, and
export the internal functions in that case.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Implement 4x4 matrix inversion based on LU-decomposition with partial
pivoting.
Instead of simply computing the inverse matrix explicitly, introduce the
type struct weston_inverse_matrix for storing the LU-decomposition and
the permutation from pivoting. Using doubles, this struct has greater
precision than struct weston_matrix.
If you need only few (less than 5, presumably) multiplications with the
inverse matrix, is it cheaper to use weston_inverse_matrix, and not
compute the inverse matrix explicitly into a weston_matrix.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Remove the inverse matrix member from struct weston_transform. It is
easier (and probably faster, too) to create and store only forward
transformation matrices in a list, multiply them once, and then invert
the final matrix, rather than creating both forward and inverse
matrices, and multiplying both.
Add a stub for the 4x4 matrix inversion function.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
This rename addresses a few problems around the split between core
Wayland and the wayland-demos repository.
1) Initially, we had one big repository with protocol code, sample
compositor and sample clients. We split that repository to make it
possible to implement the protocol without pulling in the sample/demo
code. At this point, the compositor is more than just a "demo" and
wayland-demos doesn't send the right message. The sample compositor
is a useful, self-contained project in it's own right, and we want to
move away from the "demos" label.
2) Another problem is that the wayland-demos compositor is often
called "the wayland compsitor", but it's really just one possible
compositor. Existing X11 compositors are expected to add Wayland
support and then gradually phase out/modularize the X11 support, for
example. Conversely, it's hard to talk about the wayland-demos
compositor specifically as opposed to, eg, the wayland protocol or a
wayland compositor in general.
We are also renaming the repo to weston, and the compositor
subdirectory to src/, to emphasize that the main "output" is the
compositor.
Besides the new header file, there's also a change in the main evdev creation
procedure for a more suggestive name (evdev_input_add_devices ->
evdev_input_create). There's no real functional changes in this commit.
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
Pekka Paalanen
Kristian Høgsberg
Tiago Vignatti