1 /*
2  * Copyright 2019 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 #pragma once
18 
19 #include <math/vec4.h>
20 #include <ui/Rect.h>
21 
22 #include "GLSkiaShadowPort.h"
23 
24 namespace android {
25 namespace renderengine {
26 
27 class Mesh;
28 
29 namespace gl {
30 
31 /**
32  * Generates gl attributes required to draw shadow spot and/or ambient shadows.
33  *
34  * Each shadow can support different colors. This class generates three vertex attributes for
35  * each shadow, its position, color and shadow params(offset and distance). These can be sent
36  * using a single glDrawElements call.
37  */
38 class GLShadowVertexGenerator {
39 public:
40     GLShadowVertexGenerator(const FloatRect& casterRect, float casterCornerRadius, float casterZ,
41                             bool casterIsTranslucent, const vec4& ambientColor,
42                             const vec4& spotColor, const vec3& lightPosition, float lightRadius);
43     ~GLShadowVertexGenerator() = default;
44 
45     size_t getVertexCount() const;
46     size_t getIndexCount() const;
47     void fillVertices(Mesh::VertexArray<vec2>& position, Mesh::VertexArray<vec4>& color,
48                       Mesh::VertexArray<vec3>& params) const;
49     void fillIndices(uint16_t* indices) const;
50 
51 private:
52     bool mDrawAmbientShadow;
53     std::unique_ptr<Geometry> mAmbientShadowGeometry;
54     int mAmbientShadowVertexCount = 0;
55     int mAmbientShadowIndexCount = 0;
56 
57     bool mDrawSpotShadow;
58     std::unique_ptr<Geometry> mSpotShadowGeometry;
59     int mSpotShadowVertexCount = 0;
60     int mSpotShadowIndexCount = 0;
61 };
62 
63 } // namespace gl
64 } // namespace renderengine
65 } // namespace android
66