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 "Vertex.h"
20 #include "Texture.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 
35     void constructTexture(Caches& caches);
36 
37     /**
38      * Activate the specified texture unit. The texture unit must
39      * be specified using an integer number (0 for GL_TEXTURE0 etc.)
40      */
41     void activateTexture(GLuint textureUnit);
42 
43     /**
44      * Invalidate the cached value of the active texture unit.
45      */
46     void resetActiveTexture();
47 
48     /**
49      * Binds the specified texture as a GL_TEXTURE_2D texture.
50      * All texture bindings must be performed with this method or
51      * bindTexture(GLenum, GLuint).
52      */
53     void bindTexture(GLuint texture);
54 
55     /**
56      * Binds the specified texture with the specified render target.
57      * All texture bindings must be performed with this method or
58      * bindTexture(GLuint).
59      */
60     void bindTexture(GLenum target, GLuint texture);
61 
62     /**
63      * Deletes the specified texture and clears it from the cache
64      * of bound textures.
65      * All textures must be deleted using this method.
66      */
67     void deleteTexture(GLuint texture);
68 
69     /**
70      * Signals that the cache of bound textures should be cleared.
71      * Other users of the context may have altered which textures are bound.
72      */
73     void resetBoundTextures();
74 
75     /**
76      * Clear the cache of bound textures.
77      */
78     void unbindTexture(GLuint texture);
79 
getShadowLutTexture()80     Texture* getShadowLutTexture() { return mShadowLutTexture.get(); }
81 
82 private:
83     // total number of texture units available for use
84     static const int kTextureUnitsCount = 4;
85 
86     TextureState();
87     ~TextureState();
88     GLuint mTextureUnit;
89 
90     // Caches texture bindings for the GL_TEXTURE_2D target
91     GLuint mBoundTextures[kTextureUnitsCount];
92 
93     std::unique_ptr<Texture> mShadowLutTexture;
94 };
95 
96 } /* namespace uirenderer */
97 } /* namespace android */
98 
99 #endif // RENDERSTATE_BLEND_H
100