Calculate and show the shadow from a spot light.
Change-Id: Ia558852e8cde5d33866b22875eb501e4c6858819
diff --git a/libs/hwui/SpotShadow.h b/libs/hwui/SpotShadow.h
new file mode 100644
index 0000000..d8db43bf
--- /dev/null
+++ b/libs/hwui/SpotShadow.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_HWUI_SPOT_SHADOW_H
+#define ANDROID_HWUI_SPOT_SHADOW_H
+
+#include "Debug.h"
+#include "Vector.h"
+#include "VertexBuffer.h"
+
+namespace android {
+namespace uirenderer {
+
+class SpotShadow {
+public:
+ static void createSpotShadow(const Vector3* poly, int polyLength,
+ const Vector3& lightCenter, float lightSize, int lightVertexCount,
+ int rays, int layers, float strength, VertexBuffer& retStrips);
+
+private:
+ static void computeSpotShadow(const Vector3* lightPoly, int lightPolyLength,
+ const Vector3& lightCenter, const Vector3* poly, int polyLength,
+ int rays, int layers, float strength, VertexBuffer& retstrips);
+
+ static void computeLightPolygon(int points, const Vector3& lightCenter,
+ float size, Vector3* ret);
+
+ static int getStripSize(int rays, int layers);
+ static void smoothPolygon(int level, int rays, float* rayDist);
+ static float calculateOpacity(float jf, float deltaDist);
+ static float rayIntersectPoly(const Vector2* poly, int polyLength,
+ const Vector2& point, float dx, float dy);
+
+ static Vector2 centroid2d(const Vector2* poly, int polyLength);
+
+ static void xsort(Vector2* points, int pointsLength);
+ static int hull(Vector2* points, int pointsLength, Vector2* retPoly);
+ static bool rightTurn(double ax, double ay, double bx, double by, double cx, double cy);
+ static int intersection(Vector2* poly1, int poly1length, Vector2* poly2, int poly2length);
+ static void sort(Vector2* poly, int polyLength, const Vector2& center);
+
+ static float angle(const Vector2& point, const Vector2& center);
+ static void swap(Vector2* points, int i, int j);
+ static void quicksortCirc(Vector2* points, int low, int high, const Vector2& center);
+ static void quicksortX(Vector2* points, int low, int high);
+
+ static bool testPointInsidePolygon(const Vector2 testPoint, const Vector2* poly, int len);
+ static void makeClockwise(Vector2* polygon, int len);
+ static bool isClockwise(Vector2* polygon, int len);
+ static void reverse(Vector2* polygon, int len);
+ static inline bool lineIntersection(double x1, double y1, double x2, double y2,
+ double x3, double y3, double x4, double y4, Vector2& ret);
+
+ static void generateTriangleStrip(const Vector2* penumbra, int penumbraLength,
+ const Vector2* umbra, int umbraLength, int rays, int layers,
+ float strength, VertexBuffer& retstrips);
+
+ static const double EPSILON = 1e-7;
+}; // SpotShadow
+
+}; // namespace uirenderer
+}; // namespace android
+
+#endif // ANDROID_HWUI_SPOT_SHADOW_H