1 /*
2  * Copyright (C) 2015 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 #ifndef RENDERSTATE_TEXTURESTATE_H
17 #define RENDERSTATE_TEXTURESTATE_H
18 
19 #include "Texture.h"
20 #include "Vertex.h"
21 
22 #include <GLES2/gl2.h>
23 #include <GLES2/gl2ext.h>
24 #include <memory>
25 
26 namespace android {
27 namespace uirenderer {
28 
29 class Texture;
30 
31 class TextureState {
32     friend class Caches;  // TODO: move to RenderState
33 public:
34     void constructTexture(Caches& caches);
35 
36     /**
37      * Activate the specified texture unit. The texture unit must
38      * be specified using an integer number (0 for GL_TEXTURE0 etc.)
39      */
40     void activateTexture(GLuint textureUnit);
41 
42     /**
43      * Invalidate the cached value of the active texture unit.
44      */
45     void resetActiveTexture();
46 
47     /**
48      * Binds the specified texture as a GL_TEXTURE_2D texture.
49      * All texture bindings must be performed with this method or
50      * bindTexture(GLenum, GLuint).
51      */
52     void bindTexture(GLuint texture);
53 
54     /**
55      * Binds the specified texture with the specified render target.
56      * All texture bindings must be performed with this method or
57      * bindTexture(GLuint).
58      */
59     void bindTexture(GLenum target, GLuint texture);
60 
61     /**
62      * Deletes the specified texture and clears it from the cache
63      * of bound textures.
64      * All textures must be deleted using this method.
65      */
66     void deleteTexture(GLuint texture);
67 
68     /**
69      * Signals that the cache of bound textures should be cleared.
70      * Other users of the context may have altered which textures are bound.
71      */
72     void resetBoundTextures();
73 
74     /**
75      * Clear the cache of bound textures.
76      */
77     void unbindTexture(GLuint texture);
78 
getShadowLutTexture()79     Texture* getShadowLutTexture() { return mShadowLutTexture.get(); }
80 
81 private:
82     // total number of texture units available for use
83     static const int kTextureUnitsCount = 4;
84 
85     TextureState();
86     ~TextureState();
87     GLuint mTextureUnit;
88 
89     // Caches texture bindings for the GL_TEXTURE_2D target
90     GLuint mBoundTextures[kTextureUnitsCount];
91 
92     std::unique_ptr<Texture> mShadowLutTexture;
93 };
94 
95 } /* namespace uirenderer */
96 } /* namespace android */
97 
98 #endif  // RENDERSTATE_BLEND_H
99