[gtk/curve-ops: 6/12] Add a performance test for curve intersection

[Matthias Clasen <matthiasc src gnome org>]

commit d6d47bff8986a1fb6972bd0a11b90c98516c71f9
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Dec 7 21:39:59 2020 -0500

    Add a performance test for curve intersection
    
    This shows how much more expensive curve
    intersections are.

 testsuite/gsk/curve-performance.c | 135 ++++++++++++++++++++++++++++++++++++++
 testsuite/gsk/meson.build         |   1 +
 2 files changed, 136 insertions(+)
---
diff --git a/testsuite/gsk/curve-performance.c b/testsuite/gsk/curve-performance.c
new file mode 100644
index 0000000000..d2d4aae68a
--- /dev/null
+++ b/testsuite/gsk/curve-performance.c
@@ -0,0 +1,135 @@
+#include <gtk/gtk.h>
+#include "gsk/gskcurveprivate.h"
+
+static void
+init_random_point (graphene_point_t *p)
+{
+  p->x = g_test_rand_double_range (0, 1000);
+  p->y = g_test_rand_double_range (0, 1000);
+}
+
+static void
+init_random_curve_with_op (GskCurve         *curve,
+                           GskPathOperation  min_op,
+                           GskPathOperation  max_op)
+{
+  switch (g_test_rand_int_range (min_op, max_op + 1))
+    {
+    case GSK_PATH_LINE:
+      {
+        graphene_point_t p[2];
+
+        init_random_point (&p[0]);
+        init_random_point (&p[1]);
+        gsk_curve_init (curve, gsk_pathop_encode (GSK_PATH_LINE, p));
+      }
+      break;
+
+    case GSK_PATH_CURVE:
+      {
+        graphene_point_t p[4];
+
+        init_random_point (&p[0]);
+        init_random_point (&p[1]);
+        init_random_point (&p[2]);
+        init_random_point (&p[3]);
+        gsk_curve_init (curve, gsk_pathop_encode (GSK_PATH_CURVE, p));
+      }
+    break;
+
+    case GSK_PATH_CONIC:
+      {
+        graphene_point_t p[4];
+
+        init_random_point (&p[0]);
+        init_random_point (&p[1]);
+        p[2] = GRAPHENE_POINT_INIT (g_test_rand_double_range (0, 20), 0);
+        init_random_point (&p[3]);
+        gsk_curve_init (curve, gsk_pathop_encode (GSK_PATH_CONIC, p));
+      }
+      break;
+
+    default:
+      g_assert_not_reached ();
+    }
+}
+
+static void
+test_intersection (GskPathOperation op1,
+                   GskPathOperation op2)
+{
+  GskCurve curves[10000];
+  GskCurve *c1, *c2;
+  gint64 start, time;
+  gint64 count;
+  double time_elapsed;
+  double result;
+  float t1[9], t2[9];
+  graphene_point_t p[9];
+
+  for (int i = 0; i < 5000; i++)
+    {
+      init_random_curve_with_op (&curves[i], op1, op1);
+      init_random_curve_with_op (&curves[5000 + i], op2, op2);
+    }
+
+  count = 0;
+  start = time = g_get_monotonic_time ();
+
+  while (time - start < G_TIME_SPAN_SECOND * 20)
+    {
+      c1 = &curves[g_test_rand_int_range (0, 5000)];
+      c2 = &curves[g_test_rand_int_range (5000, 10000)];
+
+      gsk_curve_intersect (c1, c2, t1, t2, p, 9);
+
+      count++;
+      if (count % 10000 == 0)
+        time = g_get_monotonic_time ();
+    }
+
+  time_elapsed = (time - start) / (double) G_TIME_SPAN_SECOND;
+  result = ((double) count / time_elapsed);
+  g_test_maximized_result (result, "%8.1f ops/s", result);
+}
+
+static void
+line_intersection (void)
+{
+  test_intersection (GSK_PATH_LINE, GSK_PATH_LINE);
+}
+
+static void
+line_curve_intersection (void)
+{
+  test_intersection (GSK_PATH_LINE, GSK_PATH_CURVE);
+}
+
+static void
+curve_intersection (void)
+{
+  test_intersection (GSK_PATH_CURVE, GSK_PATH_CURVE);
+}
+
+static void
+conic_intersection (void)
+{
+  test_intersection (GSK_PATH_CONIC, GSK_PATH_CONIC);
+}
+
+int
+main (int argc, char *argv[])
+{
+  g_test_init (&argc, &argv, NULL);
+
+  if (g_test_perf ())
+    {
+      g_test_add_func ("/curve/perf/intersection/line", line_intersection);
+      g_test_add_func ("/curve/perf/intersection/line-curve", line_curve_intersection);
+      g_test_add_func ("/curve/perf/intersection/curve", curve_intersection);
+      g_test_add_func ("/curve/perf/intersection/conic", conic_intersection);
+    }
+
+  return g_test_run ();
+}
+
diff --git a/testsuite/gsk/meson.build b/testsuite/gsk/meson.build
index 3bc72094b9..dc0604e537 100644
--- a/testsuite/gsk/meson.build
+++ b/testsuite/gsk/meson.build
@@ -191,6 +191,7 @@ tests = [
   ['curve', ['../../gsk/gskcurve.c', '../../gsk/gskcurveintersect.c'], ['-DGTK_COMPILATION']],
   ['curve-special-cases', ['../../gsk/gskcurve.c'], ['-DGTK_COMPILATION']],
   ['dash'],
+  ['curve-performance', ['../../gsk/gskcurve.c', '../../gsk/gskcurveintersect.c'], ['-DGTK_COMPILATION']],
   ['path'],
   ['path-special-cases'],
   ['rounded-rect'],