From 6f0816629db8c0310c647de3e2afae47fce1b98e Mon Sep 17 00:00:00 2001
From: Matthias Clasen <mclasen@redhat.com>
Date: Mon, 7 Dec 2020 21:39:59 -0500
Subject: [PATCH] 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(+)
 create mode 100644 testsuite/gsk/curve-performance.c

diff --git a/testsuite/gsk/curve-performance.c b/testsuite/gsk/curve-performance.c
new file mode 100644
index 0000000000..a8fa3ae806
--- /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_CUBIC:
+      {
+        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_CUBIC, 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_CUBIC);
+}
+
+static void
+curve_intersection (void)
+{
+  test_intersection (GSK_PATH_CUBIC, GSK_PATH_CUBIC);
+}
+
+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 228a0a2738..86addd99cb 100644
--- a/testsuite/gsk/meson.build
+++ b/testsuite/gsk/meson.build
@@ -392,6 +392,7 @@ endforeach
 internal_tests = [
   [ 'curve' ],
   [ 'curve-special-cases' ],
+  [ 'curve-performance' ],
   [ 'diff' ],
   [ 'half-float' ],
   ['rounded-rect'],