diff options
| -rw-r--r-- | region_to_path.c | 240 |
1 files changed, 16 insertions, 224 deletions
diff --git a/region_to_path.c b/region_to_path.c index 437bd08..bf1f2dd 100644 --- a/region_to_path.c +++ b/region_to_path.c @@ -176,238 +176,23 @@ add_hsegment (cairo_t *cr, hsegment_t *h, gboolean go_right) static void region_to_path (cairo_t *cr, cairo_region_t *region) { - int i; - GArray *hsegments = g_array_new (TRUE, TRUE, sizeof (hsegment_t)); - GArray *vsegments = g_array_new (TRUE, TRUE, sizeof (vsegment_t)); - hsegment_t h; - vsegment_t v; - - h.left = h.right = NULL; - v.top = v.bottom = NULL; + int n_rects = cairo_region_num_rectangles (region); + int n_segments = 2 * n_rects; - for (i = 0; i < cairo_region_num_rectangles (region); ++i) + hsegment_t *hsegments = g_new (hsegment_t, n_segments); + vsegment_t *vsegments = g_new (vsegment_t, n_segments); + + int i; + + for (i = 0; i < n_rects; ++i) { cairo_rectangle_int_t rect; - + cairo_region_get_rectangle (region, i, &rect); - - h.x1 = rect.x; - h.x2 = rect.x + rect.width; - - h.y = rect.y; - - g_array_append_val (hsegments, h); - - h.y = rect.y + rect.height; - - g_array_append_val (hsegments, h); - - v.y1 = rect.y; - v.y2 = rect.y + rect.height; - - v.x = rect.x; - - g_array_append_val (vsegments, v); - - v.x = rect.x + rect.width; - - g_array_append_val (vsegments, v); - } - - g_array_sort (hsegments, compare_hsegments); - g_array_sort (vsegments, compare_vsegments); - - /* Deal with overlapping hsegments */ - for (i = 1; i < hsegments->len; ++i) - { - hsegment_t *this = &g_array_index (hsegments, hsegment_t, i); - hsegment_t *prev = &g_array_index (hsegments, hsegment_t, i - 1); - - if (this->y == prev->y && this->x1 < prev->x2) - { - int tmp = prev->x2; - -#if 0 - g_print ("[%d: %d %d] and [%d: %d %d] -> ", - prev->y, prev->x1, prev->x2, - this->y, this->x1, this->x2); -#endif - - prev->x2 = this->x1; - this->x1 = tmp; - - if (this->x1 > this->x2) - { - tmp = this->x2; - this->x2 = this->x1; - this->x1 = tmp; - } - -#if 0 - g_print ("[%d: %d %d] and [%d: %d %d]\n", - prev->y, prev->x1, prev->x2, - this->y, this->x1, this->x2); -#endif - } - } - - /* Coalesce abutting vsegments */ - for (i = 1; i < vsegments->len; ++i) - { - vsegment_t *this = &g_array_index (vsegments, vsegment_t, i); - vsegment_t *prev = &g_array_index (vsegments, vsegment_t, i - 1); - - if (this->x == prev->x && this->y1 == prev->y2) - { -#if 0 - g_print (" prev %d %d %d \n", this->x, this->y1, this->y2); -#endif - /* Add 'prev' into 'this' rather than the other way around. - * This way, the next iteration only has to look at its 'prev', - * not two steps behind - */ - - prev->y2 = prev->y1; - this->y1 = prev->y1; - -#if 0 - g_print ("generated segment: %d: %d %d\n", prev->x, prev->y1, prev->y2); -#endif - } - } - - /* Finally, for each non-empty hsegment, find the corresponding - * vsegments - * FIXME: this should be done with binary search - */ - for (i = 0; i < hsegments->len; ++i) - { - hsegment_t *h = &g_array_index (hsegments, hsegment_t, i); - int j; - if (h->x1 == h->x2) - continue; - - g_assert (!h->left); - g_assert (!h->right); - for (j = 0; j < vsegments->len; ++j) - { - vsegment_t *v = &g_array_index (vsegments, vsegment_t, j); - - if (v->y1 == v->y2) - continue; - - if (v->y1 == h->y) - { - if (v->x == h->x1) - { - if (h->left) - { - g_print (" [ %d: %d %d ] already has left\n", - h->y, h->x1, h->x2); - } - - g_assert (v->top == NULL); - g_assert (h->left == NULL); - - v->top = h; - h->left = v; - } - - if (v->x == h->x2) - { - if (h->right) - { - g_print (" [ %d: %d %d ] already has right: %d %d %d\n", - h->y, h->x1, h->x2, - v->x, v->y1, v->y2); - } - g_assert (v->top == NULL); - g_assert (h->right == NULL); - - v->top = h; - h->right = v; - } - } - - if (v->y2 == h->y) - { - if (v->x == h->x1) - { - g_assert (v->bottom == NULL); - g_assert (h->left == NULL); - - v->bottom = h; - h->left = v; - } - - if (v->x == h->x2) - { - if (h->right) - { - g_print (" [ %d: %d %d ] already has right: %d %d %d\n", - h->y, h->x1, h->x2, - v->x, v->y1, v->y2); - } - - g_assert (v->bottom == NULL); - g_assert (h->right == NULL); - - v->bottom = h; - h->right = v; - } - } - } - - g_assert (h->left); - g_assert (h->right); - } - - for (i = 0; i < hsegments->len; ++i) - { - hsegment_t *h = &g_array_index (hsegments, hsegment_t, i); - - if (h->x1 != h->x2) - { - g_assert (h->left); - g_assert (h->right); - } - } - - for (i = 0; i < vsegments->len; ++i) - { - vsegment_t *v = &g_array_index (vsegments, vsegment_t, i); - - if (v->y1 != v->y2) - { - if (!v->bottom) - { - g_print ("no bottom for %d %d %d\n", v->x, v->y1, v->y2); - } - - g_assert (v->top); - g_assert (v->bottom); - } } - - if (cr) - { - for (i = 0; i < hsegments->len; ++i) - { - hsegment_t *h = &g_array_index (hsegments, hsegment_t, i); - - if (h->left) - { - cairo_move_to (cr, h->x1, h->y); - add_hsegment (cr, h, TRUE); - } - } - } - - g_array_free (hsegments, TRUE); - g_array_free (vsegments, TRUE); } static gboolean @@ -422,6 +207,13 @@ on_expose (GtkWidget *widget, GdkEvent *event, gpointer data) int i; region = cairo_region_create(); + + rect.x = 20; + rect.y = 50; + rect.width = 10; + rect.height = 10; + + cairo_region_subtract_rectangle (region, &rect); for (i = 0; i < sizeof (rects) / sizeof (rects[0]); ++i) cairo_region_union_rectangle (region, &rects[i]); |