Use SkMatrix44 for the underlying implementation of ui::Transform

ui/gfx/transform_unittest.cc

Index: ui/gfx/transform_unittest.cc
diff --git a/ui/gfx/transform_unittest.cc b/ui/gfx/transform_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e1e39b9a772a6f6f557f3fa6b16ea0bb7f714545
--- /dev/null
+++ b/ui/gfx/transform_unittest.cc
@@ -0,0 +1,264 @@
+// Copyright (c) 2006-2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/basictypes.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/eigen/Eigen/Geometry"
+#include "ui/gfx/transform.h"
+#include "ui/gfx/point.h"
+#include <iostream>
+#include <limits>
+
+typedef testing::Test XFormTest;
+
+#ifdef NDEBUG
+TEST(XFormTest, MatrixMultStressTest) {
+  ui::Transform xform;
+  for (int i = 0; i < 1000000; ++i) {
+    xform.ConcatRotate(3.0f);
+    xform.ConcatScale(2.0f, 2.0f);
+    xform.ConcatTranslate(1.0f, 2.0f);
+    xform.ConcatScale(0.5f, 0.5f);
+  }
+}
+#endif
+
+TEST(XFormTest, ConcatTranslate) {
+  static const struct TestCase {
+    int x1;
+    int y1;
+    float tx;
+    float ty;
+    int x2;
+    int y2;
+  } test_cases[] = {
+    { 0, 0, 10.0f, 20.0f, 10, 20 },
+    { 0, 0, -10.0f, -20.0f, 0, 0 },
+    { 0, 0, -10.0f, -20.0f, -10, -20 },
+    { 0, 0,
+      std::numeric_limits<float>::quiet_NaN(),
+      std::numeric_limits<float>::quiet_NaN(),
+      10, 20 },
+  };
+
+  ui::Transform xform;
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
+    const TestCase& value = test_cases[i];
+    xform.ConcatTranslate(value.tx, value.ty);
+    gfx::Point p1(value.x1, value.y1);
+    gfx::Point p2(value.x2, value.y2);
+    xform.TransformPoint(&p1);
+    if (value.tx == value.tx &&
+        value.ty == value.ty) {
+      EXPECT_EQ(p1.x(), p2.x());
+      EXPECT_EQ(p1.y(), p2.y());
+    }
+  }
+}
+
+TEST(XFormTest, ConcatScale) {
+  static const struct TestCase {
+    int before;
+    float scale;
+    int after;
+  } test_cases[] = {
+    { 1, 10.0f, 10 },
+    { 1, .1f, 1 },
+    { 1, 100.0f, 100 },
+    { 1, -1.0f, -100 },
+    { 1, std::numeric_limits<float>::quiet_NaN(), 1 }
+  };
+
+  ui::Transform xform;
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
+    const TestCase& value = test_cases[i];
+    xform.ConcatScale(value.scale, value.scale);
+    gfx::Point p1(value.before, value.before);
+    gfx::Point p2(value.after, value.after);
+    xform.TransformPoint(&p1);
+    if (value.scale == value.scale) {
+      EXPECT_EQ(p1.x(), p2.x());
+      EXPECT_EQ(p1.y(), p2.y());
+    }
+  }
+}
+
+TEST(XFormTest, ConcatRotate) {
+  static const struct TestCase {
+    int x1;
+    int y1;
+    float degrees;
+    int x2;
+    int y2;
+  } test_cases[] = {
+    { 1, 0, 90.0f, 0, 1 },
+    { 1, 0, -90.0f, 1, 0 },
+    { 1, 0, 90.0f, 0, 1 },
+    { 1, 0, 360.0f, 0, 1 },
+    { 1, 0, 0.0f, 0, 1 },
+    { 1, 0, std::numeric_limits<float>::quiet_NaN(), 1, 0 }
+  };
+
+  ui::Transform xform;
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
+    const TestCase& value = test_cases[i];
+    xform.ConcatRotate(value.degrees);
+    gfx::Point p1(value.x1, value.y1);
+    gfx::Point p2(value.x2, value.y2);
+    xform.TransformPoint(&p1);
+    if (value.degrees == value.degrees) {
+      EXPECT_EQ(p1.x(), p2.x());
+      EXPECT_EQ(p1.y(), p2.y());
+    }
+  }
+}
+
+TEST(XFormTest, SetTranslate) {
+  static const struct TestCase {
+    int x1; int y1;
+    float tx; float ty;
+    int x2; int y2;
+  } test_cases[] = {
+    { 0, 0, 10.0f, 20.0f, 10, 20 },
+    { 10, 20, 10.0f, 20.0f, 20, 40 },
+    { 10, 20, 0.0f, 0.0f, 10, 20 },
+    { 0, 0,
+      std::numeric_limits<float>::quiet_NaN(),
+      std::numeric_limits<float>::quiet_NaN(),
+      0, 0 }
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
+    const TestCase& value = test_cases[i];
+    for (int j = -1; j < 2; ++j) {
+      for (int k = 0; k < 3; ++k) {
+        float epsilon = 0.0001f;
+        gfx::Point p0, p1, p2;
+        ui::Transform xform;
+        switch (k) {
+        case 0:
+          p1.SetPoint(value.x1, 0);
+          p2.SetPoint(value.x2, 0);
+          xform.SetTranslateX(value.tx + j * epsilon);
+          break;
+        case 1:
+          p1.SetPoint(0, value.y1);
+          p2.SetPoint(0, value.y2);
+          xform.SetTranslateY(value.ty + j * epsilon);
+          break;
+        case 2:
+          p1.SetPoint(value.x1, value.y1);
+          p2.SetPoint(value.x2, value.y2);
+          xform.SetTranslate(value.tx + j * epsilon,
+                             value.ty + j * epsilon);
+          break;
+        }
+        p0 = p1;
+        xform.TransformPoint(&p1);
+        if (value.tx == value.tx &&
+            value.ty == value.ty) {
+          EXPECT_EQ(p1.x(), p2.x());
+          EXPECT_EQ(p1.y(), p2.y());
+          xform.TransformPointReverse(&p1);
+          EXPECT_EQ(p1.x(), p0.x());
+          EXPECT_EQ(p1.y(), p0.y());
+        }
+      }
+    }
+  }
+}
+
+TEST(XFormTest, SetScale) {
+  static const struct TestCase {
+    int before;
+    float s;
+    int after;
+  } test_cases[] = {
+    { 1, 10.0f, 10 },
+    { 1, 1.0f, 1 },
+    { 1, 0.0f, 0 },
+    { 0, 10.0f, 0 },
+    { 1, std::numeric_limits<float>::quiet_NaN(), 0 },
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(test_cases); ++i) {
+    const TestCase& value = test_cases[i];
+    for (int j = -1; j < 2; ++j) {
+      for (int k = 0; k < 3; ++k) {
+        float epsilon = 0.0001f;
+        gfx::Point p0, p1, p2;
+        ui::Transform xform;
+        switch (k) {
+        case 0:
+          p1.SetPoint(value.before, 0);
+          p2.SetPoint(value.after, 0);
+          xform.SetScaleX(value.s + j * epsilon);
+          break;
+        case 1:
+          p1.SetPoint(0, value.before);
+          p2.SetPoint(0, value.after);
+          xform.SetScaleY(value.s + j * epsilon);
+          break;
+        case 2:
+          p1.SetPoint(value.before,
+                      value.before);
+          p2.SetPoint(value.after,
+                      value.after);
+          xform.SetScale(value.s + j * epsilon,
+                         value.s + j * epsilon);
+          break;
+        }
+        p0 = p1;
+        xform.TransformPoint(&p1);
+        if (value.s == value.s) {
+          EXPECT_EQ(p1.x(), p2.x());
+          EXPECT_EQ(p1.y(), p2.y());
+          if (value.s != 0.0f) {
+            xform.TransformPointReverse(&p1);
+            EXPECT_EQ(p1.x(), p0.x());
+            EXPECT_EQ(p1.y(), p0.y());
+          }
+        }
+      }
+    }
+  }
+}
+
+TEST(XFormTest, SetRotate) {
+  static const struct SetRotateCase {
+    int x;
+    int y;
+    float degree;
+    int xprime;
+    int yprime;
+  } set_rotate_cases[] = {
+    { 100, 0, 90.0f, 0, 100 },
+    { 0, 0, 90.0f, 0, 0 },
+    { 0, 100, 90.0f, -100, 0 },
+    { 100, 0, 0.0f, 100, 0 },
+    { 0, 0, 0.0f, 0, 0 },
+    { 0, 0, std::numeric_limits<float>::quiet_NaN(), 0, 0 },
+    { 100, 0, 360.0f, 100, 0 }
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(set_rotate_cases); ++i) {
+    const SetRotateCase& value = set_rotate_cases[i];
+    for (int j = -1; j < 2; ++j) {
+      float epsilon = 0.0001f;
+      gfx::Point pt(value.x, value.y);
+      ui::Transform xform;
+      // should be invariant to small floating point errors.
+      xform.SetRotate(value.degree + j * epsilon);
+      // just want to make sure that we don't crash in the case of NaN.
+      if (value.degree == value.degree) {
+        xform.TransformPoint(&pt);
+        EXPECT_EQ(value.xprime, pt.x());
+        EXPECT_EQ(value.yprime, pt.y());
+        xform.TransformPointReverse(&pt);
+        EXPECT_EQ(pt.x(), value.x);
+        EXPECT_EQ(pt.y(), value.y);
+      }
+    }
+  }
+}