src/cairoint.h src/cairo-traps.c: Add _cairo_traps_extract_region for converting trapezoids into a pixman region.

Represent all rectangular pixel-aligned regions as regions, not just single rectangles.
Split into manageable pieces, optimize rectangular pixel- aligned regions by using _cairo_surface_fill_rectangles() or _cairo_surface_set_clip_region() as appropriate.
tests/trap-clip.c tests/trap-clip-ref.png tests/Makefile.am: Add a test for trapezoids clipping.
Add an index.

1 files changed, 213 insertions, 0 deletions

diff --git a/test/trap-clip.c b/test/trap-clip.c
new file mode 100644
index 000000000..4bc6f195a
--- /dev/null
+++ b/test/trap-clip.c
@@ -0,0 +1,213 @@
+/*
+ * Copyright © 2005 Red Hat, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of
+ * Red Hat, Inc. not be used in advertising or publicity pertaining to
+ * distribution of the software without specific, written prior
+ * permission. Red Hat, Inc. makes no representations about the
+ * suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL RED HAT, INC. BE LIABLE FOR ANY SPECIAL,
+ * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+ * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
+ * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Author: Kristian Høgsberg <krh@redhat.com>
+ */
+
+#include <math.h>
+#include "cairo-test.h"
+#include <stdio.h>
+
+#define WIDTH 64
+#define HEIGHT 64
+#define PAD 10
+
+const char	png_filename[]	= "romedalen.png";
+
+static void
+set_solid_pattern (cairo_t *cr, int x, int y)
+{
+    cairo_set_rgb_color (cr, 0, 0, 0.6);
+    cairo_set_alpha (cr, 1.0);
+}
+
+static void
+set_translucent_pattern (cairo_t *cr, int x, int y)
+{
+    cairo_set_rgb_color (cr, 0, 0, 0.6);
+    cairo_set_alpha (cr, 0.5);
+}
+
+static void
+set_gradient_pattern (cairo_t *cr, int x, int y)
+{
+    cairo_pattern_t *pattern;
+
+    pattern =
+	cairo_pattern_create_linear (x, y, x + WIDTH, y + HEIGHT);
+    cairo_pattern_add_color_stop (pattern, 0, 1, 1, 1, 1);
+    cairo_pattern_add_color_stop (pattern, 1, 0, 0, 0.4, 1);
+    cairo_set_pattern (cr, pattern);
+    cairo_set_alpha (cr, 1);
+}
+
+static void
+set_image_pattern (cairo_t *cr, int x, int y)
+{
+    cairo_pattern_t *pattern;
+
+    pattern = cairo_test_create_png_pattern (cr, png_filename);
+    cairo_set_pattern (cr, pattern);
+    cairo_set_alpha (cr, 1);
+}
+
+static void
+draw_rect (cairo_t *cr, int x, int y)
+{
+    cairo_new_path (cr);
+    cairo_rectangle (cr, x, y, WIDTH, HEIGHT);
+    cairo_fill (cr);
+}
+
+static void
+draw_rects (cairo_t *cr, int x, int y)
+{
+    int width = WIDTH / 3;
+    int height = HEIGHT / 2;
+  
+    cairo_new_path (cr);
+    cairo_rectangle (cr, x, y, width, height);
+    cairo_rectangle (cr, x + width, y + height, width, height);
+    cairo_rectangle (cr, x + 2 * width, y, width, height);
+    cairo_fill (cr);
+}
+
+static void
+draw_polygon (cairo_t *cr, int x, int y)
+{
+    cairo_new_path (cr);
+    cairo_move_to (cr, x, y);
+    cairo_line_to (cr, x, y + HEIGHT);
+    cairo_line_to (cr, x + WIDTH / 2, y + 3 * HEIGHT / 4);
+    cairo_line_to (cr, x + WIDTH, y + HEIGHT);
+    cairo_line_to (cr, x + WIDTH, y);
+    cairo_line_to (cr, x + WIDTH / 2, y + HEIGHT / 4);
+    cairo_close_path (cr);
+    cairo_fill (cr);
+}
+
+static void
+clip_none (cairo_t *cr, int x, int y)
+{
+}
+
+static void
+clip_rect (cairo_t *cr, int x, int y)
+{
+    cairo_set_alpha (cr, 1.0);
+    cairo_new_path (cr);
+    cairo_rectangle (cr, x + (int)WIDTH / 6, y + (int)HEIGHT / 6,
+		     4 * ((int)WIDTH  / 6), 4 * ((int)WIDTH / 6));
+    cairo_clip (cr);
+    cairo_new_path (cr);
+}
+
+static void
+clip_rects (cairo_t *cr, int x, int y)
+{
+    int height = HEIGHT / 3;
+  
+    cairo_set_alpha (cr, 1.0);
+    cairo_new_path (cr);
+    cairo_rectangle (cr, x, y, WIDTH, height);
+    cairo_rectangle (cr, x, y + 2 * height, WIDTH, height);
+    cairo_clip (cr);
+    cairo_new_path (cr);
+}
+
+static void
+clip_circle (cairo_t *cr, int x, int y)
+{
+    cairo_set_alpha (cr, 1.0);
+    cairo_new_path (cr);
+    cairo_arc (cr, x + WIDTH / 2, y + HEIGHT / 2,
+	       WIDTH / 3, 0, 2 * M_PI);
+    cairo_clip (cr);
+    cairo_new_path (cr);
+}
+
+static void (*pattern_funcs[])(cairo_t *cr, int x, int y) = {
+    set_solid_pattern,
+    set_translucent_pattern,
+    set_gradient_pattern,
+    set_image_pattern,
+};
+
+static void (*draw_funcs[])(cairo_t *cr, int x, int y) = {
+    draw_rect,
+    draw_rects,
+    draw_polygon,
+};
+
+static void (*clip_funcs[])(cairo_t *cr, int x, int y) = {
+    clip_none,
+    clip_rect,
+    clip_rects,
+    clip_circle,
+};
+
+#define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
+#define IMAGE_WIDTH (ARRAY_SIZE (pattern_funcs) * (WIDTH + PAD) + PAD)
+#define IMAGE_HEIGHT (ARRAY_SIZE (draw_funcs) * ARRAY_SIZE (clip_funcs) * (HEIGHT + PAD) + PAD)
+
+static cairo_test_t test = {
+    "trap-clip",
+    "Trapezoid clipping",
+    IMAGE_WIDTH, IMAGE_HEIGHT
+};
+
+static cairo_test_status_t
+draw (cairo_t *cr, int width, int height)
+{
+    int i, j, k, x, y;
+
+    for (k = 0; k < ARRAY_SIZE (clip_funcs); k++) {
+	for (j = 0; j < ARRAY_SIZE (draw_funcs); j++) {
+	    for (i = 0; i < ARRAY_SIZE (pattern_funcs); i++) {
+		x = i * (WIDTH + PAD) + PAD;
+		y = (ARRAY_SIZE (draw_funcs) * k + j) * (HEIGHT + PAD) + PAD;
+
+		cairo_save (cr);
+
+		cairo_move_to (cr, x, y);
+		clip_funcs[k] (cr, x, y);
+		pattern_funcs[i] (cr, x, y);
+		draw_funcs[j] (cr, x, y);
+		if (cairo_status (cr))
+		    fprintf (stderr, "%d %d HERE!\n", i, j);
+
+		cairo_restore (cr);
+	    }
+	}
+    }
+
+    if (cairo_status (cr) != CAIRO_STATUS_SUCCESS)
+	fprintf (stderr, "%d %d .HERE!\n", i, j);
+
+    return CAIRO_TEST_SUCCESS;
+}
+
+int
+main (void)
+{
+    return cairo_test (&test, draw);
+}