compositor: Move weston_matrix_transform_region to compositor.c and export it

We're going to use this to replace much of the other transform code so
it's no longer just relevant to pixman-renderer.c

Signed-off-by: Derek Foreman <derekf@osg.samsung.com>
[Pekka: add the warning about matrix restrictions]
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

diff --git a/src/compositor.c b/src/compositor.c
index 67be07d..bbac110 100644 (file)
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -726,6 +726,63 @@ weston_transformed_rect(int width, int height,
        return ret;
 }
 
+/** Transform a region by a matrix, restricted to axis-aligned transformations
+ *
+ * Warning: This function does not work for projective, affine, or matrices
+ * that encode arbitrary rotations. Only 90-degree step rotations are
+ * supported.
+ */
+WL_EXPORT void
+weston_matrix_transform_region(pixman_region32_t *dest,
+                              struct weston_matrix *matrix,
+                              pixman_region32_t *src)
+{
+       pixman_box32_t *src_rects, *dest_rects;
+       int nrects, i;
+
+       src_rects = pixman_region32_rectangles(src, &nrects);
+       dest_rects = malloc(nrects * sizeof(*dest_rects));
+       if (!dest_rects)
+               return;
+
+       for (i = 0; i < nrects; i++) {
+               struct weston_vector vec1 = {{
+                       src_rects[i].x1, src_rects[i].y1, 0, 1
+               }};
+               weston_matrix_transform(matrix, &vec1);
+               vec1.f[0] /= vec1.f[3];
+               vec1.f[1] /= vec1.f[3];
+
+               struct weston_vector vec2 = {{
+                       src_rects[i].x2, src_rects[i].y2, 0, 1
+               }};
+               weston_matrix_transform(matrix, &vec2);
+               vec2.f[0] /= vec2.f[3];
+               vec2.f[1] /= vec2.f[3];
+
+               if (vec1.f[0] < vec2.f[0]) {
+                       dest_rects[i].x1 = floor(vec1.f[0]);
+                       dest_rects[i].x2 = ceil(vec2.f[0]);
+               } else {
+                       dest_rects[i].x1 = floor(vec2.f[0]);
+                       dest_rects[i].x2 = ceil(vec1.f[0]);
+               }
+
+
+               if (vec1.f[1] < vec2.f[1]) {
+                       dest_rects[i].y1 = floor(vec1.f[1]);
+                       dest_rects[i].y2 = ceil(vec2.f[1]);
+               } else {
+                       dest_rects[i].y1 = floor(vec2.f[1]);
+                       dest_rects[i].y2 = ceil(vec1.f[1]);
+               }
+       }
+
+       pixman_region32_clear(dest);
+       pixman_region32_init_rects(dest, dest_rects, nrects);
+       free(dest_rects);
+}
+
 WL_EXPORT void
 weston_transformed_region(int width, int height,
                          enum wl_output_transform transform,

diff --git a/src/compositor.h b/src/compositor.h
index a07b51a..e64f30c 100644 (file)
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -1646,6 +1646,10 @@ weston_transformed_rect(int width, int height,
                        int32_t scale,
                        pixman_box32_t rect);
 void
+weston_matrix_transform_region(pixman_region32_t *dest,
+                               struct weston_matrix *matrix,
+                               pixman_region32_t *src);
+void
 weston_transformed_region(int width, int height,
                          enum wl_output_transform transform,
                          int32_t scale,

diff --git a/src/pixman-renderer.c b/src/pixman-renderer.c
index 793a33d..f66a11e 100644 (file)
--- a/src/pixman-renderer.c
+++ b/src/pixman-renderer.c
@@ -133,64 +133,6 @@ pixman_renderer_read_pixels(struct weston_output *output,
        return 0;
 }
 
-/*
- * Warning: This function does not work for projective, affine, or matrices
- * that encode arbitrary rotations. Only 90-degree step rotations are
- * supported.
- *
- * Luckily it is only used for output matrices, so it is fine here.
- */
-static void
-weston_matrix_transform_region(pixman_region32_t *dest,
-                              struct weston_matrix *matrix,
-                              pixman_region32_t *src)
-{
-       pixman_box32_t *src_rects, *dest_rects;
-       int nrects, i;
-
-       src_rects = pixman_region32_rectangles(src, &nrects);
-       dest_rects = malloc(nrects * sizeof(*dest_rects));
-       if (!dest_rects)
-               return;
-
-       for (i = 0; i < nrects; i++) {
-               struct weston_vector vec1 = {{
-                       src_rects[i].x1, src_rects[i].y1, 0, 1
-               }};
-               weston_matrix_transform(matrix, &vec1);
-               vec1.f[0] /= vec1.f[3];
-               vec1.f[1] /= vec1.f[3];
-
-               struct weston_vector vec2 = {{
-                       src_rects[i].x2, src_rects[i].y2, 0, 1
-               }};
-               weston_matrix_transform(matrix, &vec2);
-               vec2.f[0] /= vec2.f[3];
-               vec2.f[1] /= vec2.f[3];
-
-               if (vec1.f[0] < vec2.f[0]) {
-                       dest_rects[i].x1 = floor(vec1.f[0]);
-                       dest_rects[i].x2 = ceil(vec2.f[0]);
-               } else {
-                       dest_rects[i].x1 = floor(vec2.f[0]);
-                       dest_rects[i].x2 = ceil(vec1.f[0]);
-               }
-
-
-               if (vec1.f[1] < vec2.f[1]) {
-                       dest_rects[i].y1 = floor(vec1.f[1]);
-                       dest_rects[i].y2 = ceil(vec2.f[1]);
-               } else {
-                       dest_rects[i].y1 = floor(vec2.f[1]);
-                       dest_rects[i].y2 = ceil(vec1.f[1]);
-               }
-       }
-
-       pixman_region32_clear(dest);
-       pixman_region32_init_rects(dest, dest_rects, nrects);
-       free(dest_rects);
-}
-
 static void
 region_global_to_output(struct weston_output *output, pixman_region32_t *region)
 {