[perf] Add composite performance test.

Add a new test case to Cairo for checking the performance of Cairo's
equivalent to GDK's gdk_pixbuf_composite_color() operation. That is an
operation that happens to be extremely useful when viewing or editing
transparent images so I think it is important that it is as fast as
possible.

AUTHORS

@@ -33,6 +33,7 @@ Richard Henderson <rth@twiddle.net> "slim" macros for better shared libraries
 James Henstridge <james@daa.com.au> Build fixes related to freetype
 Graydon Hoare <graydon@redhat.com> Support for non-render X server, first real text support
 Thomas Hunger <info@teh-web.de> Initial version of cairo_in_stroke/fill
+Björn Lindqvist <bjourne@gmail.com> Performance test cases
 Kristian Høgsberg <krh@redhat.com> PDF backend, PS backend with meta-surfaces
 Amaury Jacquot <sxpert@esitcom.org> Documentation review, appplication testing
 Adrian Johnson <ajohnson@redneon.com> PDF backend improvement

perf/Makefile.am

@@ -17,6 +17,7 @@ cairo_perf_SOURCES =		\
 	cairo-stats.c		\
 	cairo-stats.h		\
 	box-outline.c		\
+	composite-checker.c	\
 	fill.c			\
 	long-lines.c		\
 	mosaic.c		\

perf/cairo-perf.c

@@ -456,5 +456,6 @@ const cairo_perf_case_t perf_cases[] = {
     { rectangles, 512, 512},
     { rounded_rectangles, 512, 512},
     { long_dashed_lines, 512, 512},
+    { composite_checker, 16, 512},
     { NULL }
 };

perf/cairo-perf.h

@@ -112,5 +112,6 @@ CAIRO_PERF_DECL (unaligned_clip);
 CAIRO_PERF_DECL (rectangles);
 CAIRO_PERF_DECL (rounded_rectangles);
 CAIRO_PERF_DECL (long_dashed_lines);
+CAIRO_PERF_DECL (composite_checker);
 
 #endif

perf/composite-checker.c

@@ -0,0 +1,108 @@
+/*
+ * Copyright © 2007 Björn Lindqvist
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Author: Björn Lindqvist <bjourne@gmail.com>
+ */
+
+#include "cairo-perf.h"
+
+/* This test case measures how much time cairo takes to render the
+ * equivalent of the following gdk-pixbuf operation:
+ *
+ *    gdk_pixbuf_composite_color(dest,
+ *                               0, 0, DST_SIZE, DST_SIZE,
+ *                               0, 0,
+ *                               SCALE, SCALE,
+ *                               gdk.INTERP_NEAREST,
+ *                               255,
+ *                               0, 0,
+ *                               8, 0x33333333, 0x88888888);
+ *
+ * Cairo is (at the time of writing) about 2-3 times as slow as
+ * gdk-pixbuf.
+ */
+#define PAT_SIZE    16
+#define SRC_SIZE    64
+
+static cairo_pattern_t *checkerboard = NULL;
+static cairo_pattern_t *src_pattern = NULL;
+
+static cairo_perf_ticks_t
+do_composite_checker (cairo_t *cr,
+                      int      width,
+                      int      height)
+{
+    /* Compute zoom so that the src_pattern covers the whole output image. */
+    double xscale = width / (double) SRC_SIZE;
+    double yscale = height / (double) SRC_SIZE;
+
+    cairo_perf_timer_start ();
+
+    cairo_identity_matrix (cr);
+
+    /* Fill the surface with our background. */
+    cairo_set_source (cr, checkerboard);
+    cairo_paint (cr);
+
+    /* Draw the scaled image on top. */
+    cairo_scale (cr, xscale, yscale);
+    cairo_set_source (cr, src_pattern);
+    cairo_paint (cr);
+
+    cairo_perf_timer_stop ();
+    return cairo_perf_timer_elapsed ();
+}
+
+void
+composite_checker (cairo_perf_t *perf,
+                   cairo_t      *cr,
+                   int           width,
+                   int           height)
+{
+    cairo_surface_t *image;
+
+    /* Create the checker pattern. We don't actually need to draw
+     * anything on it since that wouldn't affect performance.
+     */
+    image = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
+                                        PAT_SIZE,
+                                        PAT_SIZE);
+    checkerboard = cairo_pattern_create_for_surface (image);
+    cairo_pattern_set_filter (checkerboard, CAIRO_FILTER_NEAREST);
+    cairo_pattern_set_extend (checkerboard, CAIRO_EXTEND_REPEAT);
+
+    /* Create the image source pattern. Again we use the NEAREST
+     * filtering which should be fastest.
+    */
+    image = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
+                                        SRC_SIZE,
+                                        SRC_SIZE);
+    src_pattern = cairo_pattern_create_for_surface (image);
+    cairo_pattern_set_filter (src_pattern, CAIRO_FILTER_NEAREST);
+
+    cairo_perf_run (perf, "composite-checker", do_composite_checker);
+
+    /* Frees the associated surfaces too. */
+    cairo_pattern_destroy (checkerboard);
+    cairo_pattern_destroy (src_pattern);
+}