OpenGL.h

#pragma once

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2018 Filip Wasil and Fillwave community members
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include <flw/Config.h>

#if defined(__APPLE__)

#include <OpenGL/gl3.h>

#elif defined(_WIN32) || defined(_WIN64)

#include <glad/glad.h>

bool initExtensions();

#else /* defined(__APPLE__) || defined(_WIN32) || defined(_WIN64) */

#if defined(__ANDROID__)

#define GLFW_INCLUDE_ES2
#define GL_GLEXT_PROTOTYPES

#include <GLES3/gl3.h>
#include <GLES3/gl3ext.h>

#define glClearDepth glClearDepthf
#define GL_CLAMP_TO_BORDER GL_CLAMP_TO_EDGE
#define GL_DEPTH_COMPONENT32 GL_DEPTH_COMPONENT32F

#elif defined(FILLWAVE_BACKEND_OPENGL_ES_30) || defined(FILLWAVE_BACKEND_OPENGL_ES_20)

#include <glad/glad.h>

#define glClearDepth glClearDepthf

#ifndef GL_CLAMP_TO_BORDER
#define GL_CLAMP_TO_BORDER GL_CLAMP_TO_EDGE
#endif

#ifndef GL_DEPTH_COMPONENT32
#define GL_DEPTH_COMPONENT32 GL_DEPTH_COMPONENT32F
#endif

bool initExtensions(void (* (*getAddress)(const char*))());

#else /* defined(__ANDROID__) || defined(FILLWAVE_BACKEND_OPENGL_ES_30) */

#include <glad/glad.h>

bool initExtensions();

#endif /* defined(__ANDROID__) */

#endif /* defined(__APPLE__) || defined(_WIN32) || defined(_WIN64) */

#if defined(GL_TEXTURE31)
constexpr GLint MAX_TEXTURE_UNITS = 32;
#elif defined(GL_TEXTURE16)
constexpr GLint MAX_TEXTURE_UNITS = 16;
#elif defined(GL_TEXTURE8)
constexpr GLint MAX_TEXTURE_UNITS = 8;
#elif defined(GL_TEXTURE4)
constexpr GLint MAX_TEXTURE_UNITS = 4;
#else
constexpr GLint MAX_TEXTURE_UNITS = 1;
#endif

/* Textures */
constexpr GLint FILLWAVE_POSITION_ATTACHMENT = 0;
constexpr GLint FILLWAVE_DIFFUSE_ATTACHMENT = 1;
constexpr GLint FILLWAVE_NORMAL_ATTACHMENT = 2;
constexpr GLint FILLWAVE_SPECULAR_ATTACHMENT = 3;
constexpr GLint FILLWAVE_FINAL_ATTACHMENT = 4;
constexpr GLint FILLWAVE_DIFFUSE_UNIT = 5;
constexpr GLint FILLWAVE_NORMAL_UNIT = 6;
constexpr GLint FILLWAVE_SPECULAR_UNIT = 7;
constexpr GLint FILLWAVE_NOISE_UNIT = 8;
constexpr GLint FILLWAVE_AO_UNIT = 9;
constexpr GLint FILLWAVE_SHADOW_FIRST_UNIT = 10;

/* Uniforms */
constexpr unsigned int FILLWAVE_LIGHTS_BINDING_POINT = 0;
constexpr int FILLWAVE_UNIFORM_NOT_FOUND = -1;

constexpr float FILLWAVE_AO_SAMPLE_RADIUS = 1.6f;
constexpr unsigned int FILLWAVE_OQ_VERTICES = 36;

constexpr GLsizei FILLWAVE_GLOBJECTS_MAX = 10;

/* OpenGL globals */
unsigned int getFramebufferStatus();

unsigned int getGlError();