Implement DOMQuad of geometry interfaces.

Source/core/dom/DOMQuad.cpp

Index: Source/core/dom/DOMQuad.cpp
diff --git a/Source/core/dom/DOMQuad.cpp b/Source/core/dom/DOMQuad.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..ba5f1906532e8868fc33a62754e381bb5e065a9a
--- /dev/null
+++ b/Source/core/dom/DOMQuad.cpp
@@ -0,0 +1,110 @@
+// Copyright 2015 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 "config.h"
+#include "core/dom/DOMQuad.h"
+
+#include "core/dom/DOMPointInit.h"
+#include "core/dom/DOMRectInit.h"
+
+namespace blink {
+
+DOMQuadPoint* DOMQuadPoint::create(const DOMPointInit& point, Member<DOMQuad> quad)
+{
+    return new DOMQuadPoint(point.x(), point.y(), quad);
+}
+
+DOMQuadPoint* DOMQuadPoint::create(double x, double y, Member<DOMQuad> quad)
+{
+    return new DOMQuadPoint(x, y, quad);
+}
+
+DOMQuadPoint::DOMQuadPoint(double x, double y, Member<DOMQuad> quad)
+    : DOMPoint(x, y, 0, 1)
+    , m_quad(quad)
+{
+}
+
+void DOMQuadPoint::setX(double x)
+{
+    m_x = x;
+    m_quad->updateHorizontalBounds();
+}
+
+void DOMQuadPoint::setY(double y)
+{
+    m_y = y;
+    m_quad->updateVerticalBounds();
+}
+
+DOMQuad* DOMQuad::create(const DOMRectInit& rect)
+{
+    return new DOMQuad(rect);
+}
+
+DOMQuad* DOMQuad::create(const DOMPointInit& p1, const DOMPointInit& p2,
+    const DOMPointInit& p3, const DOMPointInit& p4)
+{
+    return new DOMQuad(p1, p2, p3, p4);
+}
+
+DOMQuad::DOMQuad(const DOMRectInit& rect)
+    : m_p1(DOMQuadPoint::create(rect.x(), rect.y(), this))
+    , m_p2(DOMQuadPoint::create(rect.x() + rect.width(), rect.y(), this))
+    , m_p3(DOMQuadPoint::create(rect.x() + rect.width(), rect.y() + rect.height(), this))
+    , m_p4(DOMQuadPoint::create(rect.x(), rect.y() + rect.height(), this))
+    , m_bounds(DOMRect::create(rect.x(), rect.y(), rect.width(), rect.height()))
+{
+}
+
+DOMQuad::DOMQuad(const DOMPointInit& p1, const DOMPointInit& p2,
+    const DOMPointInit& p3, const DOMPointInit& p4)
+    : m_p1(DOMQuadPoint::create(p1, this))
+    , m_p2(DOMQuadPoint::create(p2, this))
+    , m_p3(DOMQuadPoint::create(p3, this))
+    , m_p4(DOMQuadPoint::create(p4, this))
+    , m_bounds(nullptr)
+{
+}
+
+DOMRectReadOnly* DOMQuad::bounds()
+{
+    if (!m_bounds) {
+        m_bounds = DOMRect::create();
+        updateHorizontalBounds();
+        updateVerticalBounds();
+    }
+
+    return m_bounds;
+}
+
+static inline double min4(double a, double b, double c, double d)
+{
+    return std::min(std::min(a, b), std::min(c, d));
+}
+
+static inline double max4(double a, double b, double c, double d)
+{
+    return std::max(std::max(a, b), std::max(c, d));
+}
+
+void DOMQuad::updateHorizontalBounds()
+{
+    double left = min4(m_p1->x(), m_p2->x(), m_p3->x(), m_p4->x());
+    double right = max4(m_p1->x(), m_p2->x(), m_p3->x(), m_p4->x());
+
+    m_bounds->setX(left);
+    m_bounds->setWidth(right - left);
+}
+
+void DOMQuad::updateVerticalBounds()
+{
+    double top = min4(m_p1->y(), m_p2->y(), m_p3->y(), m_p4->y());
+    double bottom = max4(m_p1->y(), m_p2->y(), m_p3->y(), m_p4->y());
+
+    m_bounds->setY(top);
+    m_bounds->setHeight(bottom - top);
+}
+
+} // namespace blink