SpotShadow.h revision 726118b35240957710d4d85fb5747e2ba8b934f7 
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_HWUI_SPOT_SHADOW_H
18#define ANDROID_HWUI_SPOT_SHADOW_H
19
20#include "Debug.h"
21#include "Vector.h"
22#include "VertexBuffer.h"
23
24namespace android {
25namespace uirenderer {
26
27class SpotShadow {
28public:
29    static void createSpotShadow(const Vector3* poly, int polyLength,
30            const Vector3& lightCenter, float lightSize, int lightVertexCount,
31            VertexBuffer& retStrips);
32
33private:
34    static void computeSpotShadow(const Vector3* lightPoly, int lightPolyLength,
35            const Vector3& lightCenter, const Vector3* poly, int polyLength,
36            VertexBuffer& retstrips);
37
38    static void computeLightPolygon(int points, const Vector3& lightCenter,
39            float size, Vector3* ret);
40
41    static int  getStripSize(int rays);
42    static void smoothPolygon(int level, int rays, float* rayDist);
43    static float rayIntersectPoly(const Vector2* poly, int polyLength,
44            const Vector2& point, float dx, float dy);
45
46    static void xsort(Vector2* points, int pointsLength);
47    static int hull(Vector2* points, int pointsLength, Vector2* retPoly);
48    static bool ccw(double ax, double ay, double bx, double by, double cx, double cy);
49    static int intersection(Vector2* poly1, int poly1length, Vector2* poly2, int poly2length);
50    static void sort(Vector2* poly, int polyLength, const Vector2& center);
51
52    static void swap(Vector2* points, int i, int j);
53    static void quicksortCirc(Vector2* points, int low, int high, const Vector2& center);
54    static void quicksortX(Vector2* points, int low, int high);
55
56    static bool testPointInsidePolygon(const Vector2 testPoint, const Vector2* poly, int len);
57    static void makeClockwise(Vector2* polygon, int len);
58    static bool isClockwise(Vector2* polygon, int len);
59    static void reverse(Vector2* polygon, int len);
60    static inline bool lineIntersection(double x1, double y1, double x2, double y2,
61            double x3, double y3, double x4, double y4, Vector2& ret);
62
63    static void generateTriangleStrip(const Vector2* penumbra, int penumbraLength,
64            const Vector2* umbra, int umbraLength, VertexBuffer& retstrips);
65
66#if DEBUG_SHADOW
67    // Verification utility function.
68    static bool testConvex(const Vector2* polygon, int polygonLength,
69            const char* name);
70    static void testIntersection(const Vector2* poly1, int poly1Length,
71        const Vector2* poly2, int poly2Length,
72        const Vector2* intersection, int intersectionLength);
73    static void updateBound(const Vector2 inVector, Vector2& lowerBound, Vector2& upperBound );
74#endif
75
76}; // SpotShadow
77
78}; // namespace uirenderer
79}; // namespace android
80
81#endif // ANDROID_HWUI_SPOT_SHADOW_H
82