1 files changed, 134 insertions, 0 deletions
diff --git a/gfx/2d/Matrix.cpp b/gfx/2d/Matrix.cpp
new file mode 100644
index 000000000..b3fce00ba
--- /dev/null
+++ b/gfx/2d/Matrix.cpp
@@ -0,0 +1,134 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Matrix.h"
+#include "Quaternion.h"
+#include "Tools.h"
+#include <algorithm>
+#include <ostream>
+#include <math.h>
+#include <float.h>  // for FLT_EPSILON
+
+#include "mozilla/FloatingPoint.h" // for UnspecifiedNaN
+
+using namespace std;
+
+
+namespace mozilla {
+namespace gfx {
+
+/* Force small values to zero.  We do this to avoid having sin(360deg)
+ * evaluate to a tiny but nonzero value.
+ */
+double
+FlushToZero(double aVal)
+{
+  // XXX Is double precision really necessary here
+  if (-FLT_EPSILON < aVal && aVal < FLT_EPSILON) {
+    return 0.0f;
+  } else {
+    return aVal;
+  }
+}
+
+/* Computes tan(aTheta).  For values of aTheta such that tan(aTheta) is
+ * undefined or very large, SafeTangent returns a manageably large value
+ * of the correct sign.
+ */
+double
+SafeTangent(double aTheta)
+{
+  // XXX Is double precision really necessary here
+  const double kEpsilon = 0.0001;
+
+  /* tan(theta) = sin(theta)/cos(theta); problems arise when
+   * cos(theta) is too close to zero.  Limit cos(theta) to the
+   * range [-1, -epsilon] U [epsilon, 1].
+   */
+
+  double sinTheta = sin(aTheta);
+  double cosTheta = cos(aTheta);
+
+  if (cosTheta >= 0 && cosTheta < kEpsilon) {
+    cosTheta = kEpsilon;
+  } else if (cosTheta < 0 && cosTheta >= -kEpsilon) {
+    cosTheta = -kEpsilon;
+  }
+  return FlushToZero(sinTheta / cosTheta);
+}
+
+std::ostream&
+operator<<(std::ostream& aStream, const Matrix& aMatrix)
+{
+  return aStream << "[ " << aMatrix._11
+                 << " "  << aMatrix._12
+                 << "; " << aMatrix._21
+                 << " "  << aMatrix._22
+                 << "; " << aMatrix._31
+                 << " "  << aMatrix._32
+                 << "; ]";
+}
+
+Matrix
+Matrix::Rotation(Float aAngle)
+{
+  Matrix newMatrix;
+
+  Float s = sinf(aAngle);
+  Float c = cosf(aAngle);
+
+  newMatrix._11 = c;
+  newMatrix._12 = s;
+  newMatrix._21 = -s;
+  newMatrix._22 = c;
+
+  return newMatrix;
+}
+
+Rect
+Matrix::TransformBounds(const Rect &aRect) const
+{
+  int i;
+  Point quad[4];
+  Float min_x, max_x;
+  Float min_y, max_y;
+
+  quad[0] = TransformPoint(aRect.TopLeft());
+  quad[1] = TransformPoint(aRect.TopRight());
+  quad[2] = TransformPoint(aRect.BottomLeft());
+  quad[3] = TransformPoint(aRect.BottomRight());
+
+  min_x = max_x = quad[0].x;
+  min_y = max_y = quad[0].y;
+
+  for (i = 1; i < 4; i++) {
+    if (quad[i].x < min_x)
+      min_x = quad[i].x;
+    if (quad[i].x > max_x)
+      max_x = quad[i].x;
+
+    if (quad[i].y < min_y)
+      min_y = quad[i].y;
+    if (quad[i].y > max_y)
+      max_y = quad[i].y;
+  }
+
+  return Rect(min_x, min_y, max_x - min_x, max_y - min_y);
+}
+
+Matrix&
+Matrix::NudgeToIntegers()
+{
+  NudgeToInteger(&_11);
+  NudgeToInteger(&_12);
+  NudgeToInteger(&_21);
+  NudgeToInteger(&_22);
+  NudgeToInteger(&_31);
+  NudgeToInteger(&_32);
+  return *this;
+}
+
+} // namespace gfx
+} // namespace mozilla