1 files changed, 74 insertions, 0 deletions
diff --git a/cc/layer_quad.cc b/cc/layer_quad.cc
new file mode 100644
index 0000000..9642622
--- /dev/null
+++ b/cc/layer_quad.cc
@@ -0,0 +1,74 @@
+// Copyright 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 "config.h"
+
+#if USE(ACCELERATED_COMPOSITING)
+
+#include "CCLayerQuad.h"
+
+namespace cc {
+
+CCLayerQuad::Edge::Edge(const FloatPoint& p, const FloatPoint& q)
+{
+    ASSERT(p != q);
+
+    FloatPoint tangent(p.y() - q.y(), q.x() - p.x());
+    float cross2 = p.x() * q.y() - q.x() * p.y();
+
+    set(tangent.x(), tangent.y(), cross2);
+    scale(1.0f / tangent.length());
+}
+
+CCLayerQuad::CCLayerQuad(const FloatQuad& quad)
+{
+    // Create edges.
+    m_left = Edge(quad.p4(), quad.p1());
+    m_right = Edge(quad.p2(), quad.p3());
+    m_top = Edge(quad.p1(), quad.p2());
+    m_bottom = Edge(quad.p3(), quad.p4());
+
+    float sign = quad.isCounterclockwise() ? -1 : 1;
+    m_left.scale(sign);
+    m_right.scale(sign);
+    m_top.scale(sign);
+    m_bottom.scale(sign);
+}
+
+CCLayerQuad::CCLayerQuad(const Edge& left, const Edge& top, const Edge& right, const Edge& bottom)
+    : m_left(left)
+    , m_top(top)
+    , m_right(right)
+    , m_bottom(bottom)
+{
+}
+
+FloatQuad CCLayerQuad::floatQuad() const
+{
+    return FloatQuad(m_left.intersect(m_top),
+                     m_top.intersect(m_right),
+                     m_right.intersect(m_bottom),
+                     m_bottom.intersect(m_left));
+}
+
+void CCLayerQuad::toFloatArray(float flattened[12]) const
+{
+    flattened[0] = m_left.x();
+    flattened[1] = m_left.y();
+    flattened[2] = m_left.z();
+    flattened[3] = m_top.x();
+    flattened[4] = m_top.y();
+    flattened[5] = m_top.z();
+    flattened[6] = m_right.x();
+    flattened[7] = m_right.y();
+    flattened[8] = m_right.z();
+    flattened[9] = m_bottom.x();
+    flattened[10] = m_bottom.y();
+    flattened[11] = m_bottom.z();
+}
+
+} // namespace cc
+
+#endif // USE(ACCELERATED_COMPOSITING)