opengl_util.h

/********************************************************************
 * Copyright (C) 2015 Liangliang Nan <liangliang.nan@gmail.com>
 * https://3d.bk.tudelft.nl/liangliang/
 *
 * This file is part of Easy3D. If it is useful in your research/work,
 * I would be grateful if you show your appreciation by citing it:
 * ------------------------------------------------------------------
 *      Liangliang Nan.
 *      Easy3D: a lightweight, easy-to-use, and efficient C++ library
 *      for processing and rendering 3D data.
 *      Journal of Open Source Software, 6(64), 3255, 2021.
 * ------------------------------------------------------------------
 *
 * Easy3D is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License Version 3
 * as published by the Free Software Foundation.
 *
 * Easy3D is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 ********************************************************************/
 
#ifndef EASY3D_RENDERER_OPENGL_UTIL_H
#define EASY3D_RENDERER_OPENGL_UTIL_H
 
#include <string>
#include <iostream>
#include <unordered_map>
 
 
namespace easy3d {

    class OpenglUtil {
    public:
        static bool init();
        static bool is_initialized();
 
        // -------------- general information --------------

        static int gl_profile();

        static bool is_supported(const std::string &name);  // e.g., "GL_VERSION_3_2", "GL_ARB_vertex_array_object"
        static bool has_extension(const std::string &name); // e.g., "GL_EXT_framebuffer_object"
        static std::string glew_version();
        static std::string gl_vendor();
        static std::string gl_renderer();
        static std::string gl_version();
        static std::string gl_extensions();
        static std::string glsl_version();
        static int gl_major_version();
        static int gl_minor_version();
        static float glew_version_number();
        static float gl_version_number();
        static float glsl_version_number();
        static int samples();

        static void viewport(int &x, int &y, int &width, int &height);
 
        // ----------------- GPU memory  -------------------

        static int total_gpu_memory();
        static int available_gpu_memory();
 
        // ----------------- print information  -------------------

        static void set_output(std::ostream *out);
 
        // --------------- buffer information ----------------

        static void get_current_buffer_info();

        static void get_buffer_info(unsigned int target, int bufferName);
 
        // --------------- GLSL information (GLSL version 4.2 is supported )----------------

        static void get_vao_info(unsigned int buffer);

        static void get_program_info(unsigned int program);

        static void get_attributes_info(unsigned int program);

        static void get_uniforms_info(unsigned int program);

        static void get_uniform_info(unsigned int program, const std::string &uniName);

        static void
        get_uniform_in_block_info(unsigned int program, const std::string &blockName, const std::string &uniName);
 
    private:
        static void _add_message(std::string format, ...);
 
        static bool _init();
 
        static int _get_rows(unsigned int type);
 
        static int _get_columns(unsigned int type);
 
        static void _display_uniformf(float *f, int rows, int columns);
 
        static void _display_uniformi(int *f, int rows, int columns);
 
        static void _display_uniformui(unsigned int *f, int rows, int columns);
 
        static void _display_uniformd(double *f, int rows, int columns);
 
        static int _get_uniform_byte_size(int size, int uniType, int arrayStride, int matStride);
 
        enum Types {
            DONT_KNOW, INT, UNSIGNED_INT, FLOAT, DOUBLE
        };
 
        static Types _get_type(unsigned int type);
 
    private:
        static bool _glew_initialized;
 
        static bool _spInit;
 
        static std::ostream *_output_stream;
 
        static std::unordered_map<int, std::string> spBufferAccess;
        static std::unordered_map<int, std::string> spBufferUsage;
        static std::unordered_map<int, std::string> spBufferBinding;
        static std::unordered_map<int, int> spBufferBound;
        static std::unordered_map<int, int> spBoundBuffer;
        static std::unordered_map<int, std::string> spDataF;
        static std::unordered_map<int, std::string> spGLSLType;
        static std::unordered_map<int, int> spGLSLTypeSize;
        static std::unordered_map<int, std::string> spShaderType;
        static std::unordered_map<int, std::string> spTransFeedBufferMode;
        static std::unordered_map<int, std::string> spGLSLPrimitives;
        static std::unordered_map<int, std::string> spTessGenSpacing;
        static std::unordered_map<int, std::string> spVertexOrder;
    };
 
}
 
#endif  // EASY3D_RENDERER_OPENGL_UTIL_H