diff options
Diffstat (limited to 'util')
| -rw-r--r-- | util/region.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/util/region.c b/util/region.c index 88e38fd2..38f84c5e 100644 --- a/util/region.c +++ b/util/region.c @@ -128,3 +128,52 @@ void wlr_region_expand(pixman_region32_t *dst, pixman_region32_t *src, pixman_region32_init_rects(dst, dst_rects, nrects); free(dst_rects); } + +void wlr_region_rotated_bounds(pixman_region32_t *dst, pixman_region32_t *src, + float rotation, int ox, int oy) { + if (rotation == 0) { + pixman_region32_copy(dst, src); + return; + } + + int nrects; + pixman_box32_t *src_rects = pixman_region32_rectangles(src, &nrects); + + pixman_box32_t *dst_rects = malloc(nrects * sizeof(pixman_box32_t)); + if (dst_rects == NULL) { + return; + } + + for (int i = 0; i < nrects; ++i) { + double x1 = src_rects[i].x1 - ox; + double y1 = src_rects[i].y1 - oy; + double x2 = src_rects[i].x2 - ox; + double y2 = src_rects[i].y2 - oy; + + double rx1 = x1 * cos(rotation) - y1 * sin(rotation); + double ry1 = x1 * sin(rotation) + y1 * cos(rotation); + + double rx2 = x2 * cos(rotation) - y1 * sin(rotation); + double ry2 = x2 * sin(rotation) + y1 * cos(rotation); + + double rx3 = x2 * cos(rotation) - y2 * sin(rotation); + double ry3 = x2 * sin(rotation) + y2 * cos(rotation); + + double rx4 = x1 * cos(rotation) - y2 * sin(rotation); + double ry4 = x1 * sin(rotation) + y2 * cos(rotation); + + x1 = fmin(fmin(rx1, rx2), fmin(rx3, rx4)); + y1 = fmin(fmin(ry1, ry2), fmin(ry3, ry4)); + x2 = fmax(fmax(rx1, rx2), fmax(rx3, rx4)); + y2 = fmax(fmax(ry1, ry2), fmax(ry3, ry4)); + + dst_rects[i].x1 = floor(ox + x1); + dst_rects[i].x2 = ceil(ox + x2); + dst_rects[i].y1 = floor(oy + y1); + dst_rects[i].y2 = ceil(oy + y2); + } + + pixman_region32_fini(dst); + pixman_region32_init_rects(dst, dst_rects, nrects); + free(dst_rects); +} |