android/android-emugl/host/libs/libOpenglRender/TextureResize.h

/*
* Copyright (C) 2015 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 _LIBRENDER_TEXTURERESIZE_H
#define _LIBRENDER_TEXTURERESIZE_H

#include <GLES2/gl2.h>

class TextureResize {
public:
    TextureResize(GLuint width, GLuint height);
    ~TextureResize();

    // Scales the given texture for the current viewport and returns the scaled
    // texture. May return the input if no scaling is required.
    GLuint update(GLuint texture);

    struct Framebuffer {
        GLuint texture;
        GLuint framebuffer;
        GLuint program;
        GLuint aPosition;
        GLuint uTexture;
    };

private:
    void setupFramebuffers(unsigned int factor);
    void resize(GLuint texture);

private:
    GLuint mWidth;
    GLuint mHeight;
    unsigned int mFactor;
    Framebuffer mFBWidth;
    Framebuffer mFBHeight;
    GLuint mVertexBuffer;
    GLenum mTextureDataType;
};

#endif