render/pixman: avoid sqrt() in render_quad without rotation

When the matrix doesn't have a rotation, we can avoid a sqrt() call.

Tested with Sway's tabbed containers.
This commit is contained in:
Simon Ser 2021-05-19 11:00:30 +02:00 committed by Simon Zeni
parent 66e100ffbf
commit f73c04b801

View file

@ -230,10 +230,14 @@ static void pixman_render_quad_with_matrix(struct wlr_renderer *wlr_renderer,
memcpy(m, matrix, sizeof(m));
// TODO get the width/height from the caller instead of extracting them
// TODO detect non rotation with matrix[1] == 0 and matrix[4] == 0 to avoid
// doing the calculation
float width = sqrt(matrix[0] * matrix[0] + matrix[1] * matrix[1]);
float height = sqrt(matrix[3] * matrix[3] + matrix[4] * matrix[4]);
float width, height;
if (matrix[1] == 0.0 && matrix[3] == 0.0) {
width = fabs(matrix[0]);
height = fabs(matrix[4]);
} else {
width = sqrt(matrix[0] * matrix[0] + matrix[1] * matrix[1]);
height = sqrt(matrix[3] * matrix[3] + matrix[4] * matrix[4]);
}
wlr_matrix_scale(m, 1.0 / width, 1.0 / height);