/* $Id$ */ /* * This file is part of OpenTTD. * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2. * OpenTTD 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 OpenTTD. If not, see . */ /** @file opengl_v.cpp OpenGL video driver support. */ #include "../stdafx.h" #if defined(_WIN32) # include #endif #if defined(__APPLE__) # include #else # include #endif #include "../3rdparty/opengl/glext.h" #include "opengl.h" #include "../core/geometry_func.hpp" #include "../core/mem_func.hpp" #include "../core/math_func.hpp" #include "../gfx_func.h" #include "../debug.h" #include "../blitter/factory.hpp" #include "../table/opengl_shader.h" #include "../safeguards.h" static PFNGLDEBUGMESSAGECONTROLPROC _glDebugMessageControl; static PFNGLDEBUGMESSAGECALLBACKPROC _glDebugMessageCallback; static PFNGLACTIVETEXTUREPROC _glActiveTexture; static PFNGLGENBUFFERSPROC _glGenBuffers; static PFNGLDELETEBUFFERSPROC _glDeleteBuffers; static PFNGLBINDBUFFERPROC _glBindBuffer; static PFNGLBUFFERDATAPROC _glBufferData; static PFNGLMAPBUFFERPROC _glMapBuffer; static PFNGLUNMAPBUFFERPROC _glUnmapBuffer; static PFNGLGENVERTEXARRAYSPROC _glGenVertexArrays; static PFNGLDELETEVERTEXARRAYSPROC _glDeleteVertexArrays; static PFNGLBINDVERTEXARRAYPROC _glBindVertexArray; static PFNGLCREATEPROGRAMPROC _glCreateProgram; static PFNGLDELETEPROGRAMPROC _glDeleteProgram; static PFNGLLINKPROGRAMPROC _glLinkProgram; static PFNGLUSEPROGRAMPROC _glUseProgram; static PFNGLGETPROGRAMIVPROC _glGetProgramiv; static PFNGLGETPROGRAMINFOLOGPROC _glGetProgramInfoLog; static PFNGLCREATESHADERPROC _glCreateShader; static PFNGLDELETESHADERPROC _glDeleteShader; static PFNGLSHADERSOURCEPROC _glShaderSource; static PFNGLCOMPILESHADERPROC _glCompileShader; static PFNGLATTACHSHADERPROC _glAttachShader; static PFNGLGETSHADERIVPROC _glGetShaderiv; static PFNGLGETSHADERINFOLOGPROC _glGetShaderInfoLog; static PFNGLGETUNIFORMLOCATIONPROC _glGetUniformLocation; static PFNGLUNIFORM1IPROC _glUniform1i; static PFNGLGETATTRIBLOCATIONPROC _glGetAttribLocation; static PFNGLENABLEVERTEXATTRIBARRAYPROC _glEnableVertexAttribArray; static PFNGLDISABLEVERTEXATTRIBARRAYPROC _glDisableVertexAttribArray; static PFNGLVERTEXATTRIBPOINTERARBPROC _glVertexAttribPointer; static PFNGLBINDFRAGDATALOCATIONPROC _glBindFragDataLocation; /** A simple 2D vertex with just position and texture. */ struct Simple2DVertex { float x, y; float u, v; }; /* static */ OpenGLBackend *OpenGLBackend::instance = nullptr; GetOGLProcAddressProc GetOGLProcAddress; /** * Find a substring in a string made of space delimited elements. The substring * has to match the complete element, partial matches don't count. * @param string List of space delimited elements. * @param substring Substring to find. * @return Pointer to the start of the match or nullptr if the substring is not present. */ const char *FindStringInExtensionList(const char *string, const char *substring) { while (1) { /* Is the extension string present at all? */ const char *pos = strstr(string, substring); if (pos == nullptr) break; /* Is this a real match, i.e. are the chars before and after the matched string * indeed spaces (or the start or end of the string, respectively)? */ const char *end = pos + strlen(substring); if ((pos == string || pos[-1] == ' ') && (*end == ' ' || *end == '\0')) return pos; /* False hit, try again for the remaining string. */ string = end; } return nullptr; } /** * Check if an OpenGL extension is supported by the current context. * @param extension The extension string to test. * @return True if the extension is supported, false if not. */ static bool IsOpenGLExtensionSupported(const char *extension) { static PFNGLGETSTRINGIPROC glGetStringi = nullptr; static bool glGetStringi_loaded = false; /* Starting with OpenGL 3.0 the preferred API to get the extensions * has changed. Try to load the required function once. */ if (!glGetStringi_loaded) { if (IsOpenGLVersionAtLeast(3, 0)) glGetStringi = (PFNGLGETSTRINGIPROC)GetOGLProcAddress("glGetStringi"); glGetStringi_loaded = true; } if (glGetStringi != nullptr) { /* New style: Each supported extension can be queried and compared independently. */ GLint num_exts; glGetIntegerv(GL_NUM_EXTENSIONS, &num_exts); for (GLint i = 0; i < num_exts; i++) { const char *entry = (const char *)glGetStringi(GL_EXTENSIONS, i); if (strcmp(entry, extension) == 0) return true; } } else { /* Old style: A single, space-delimited string for all extensions. */ return FindStringInExtensionList((const char *)glGetString(GL_EXTENSIONS), extension) != nullptr; } return false; } static byte _gl_major_ver = 0; ///< Major OpenGL version. static byte _gl_minor_ver = 0; ///< Minor OpenGL version. /** * Check if the current OpenGL version is equal or higher than a given one. * @param major Minimal major version. * @param minor Minimal minor version. * @pre OpenGL was initialized. * @return True if the OpenGL version is equal or higher than the requested one. */ bool IsOpenGLVersionAtLeast(byte major, byte minor) { return (_gl_major_ver > major) || (_gl_major_ver == major && _gl_minor_ver >= minor); } /** Bind texture-related extension functions. */ static bool BindTextureExtensions() { if (IsOpenGLVersionAtLeast(1, 3)) { _glActiveTexture = (PFNGLACTIVETEXTUREPROC)GetOGLProcAddress("glActiveTexture"); } else { _glActiveTexture = (PFNGLACTIVETEXTUREPROC)GetOGLProcAddress("glActiveTextureARB"); } return _glActiveTexture != nullptr; } /** Bind vertex buffer object extension functions. */ static bool BindVBOExtension() { if (IsOpenGLVersionAtLeast(1, 5)) { _glGenBuffers = (PFNGLGENBUFFERSPROC)GetOGLProcAddress("glGenBuffers"); _glDeleteBuffers = (PFNGLDELETEBUFFERSPROC)GetOGLProcAddress("glDeleteBuffers"); _glBindBuffer = (PFNGLBINDBUFFERPROC)GetOGLProcAddress("glBindBuffer"); _glBufferData = (PFNGLBUFFERDATAPROC)GetOGLProcAddress("glBufferData"); _glMapBuffer = (PFNGLMAPBUFFERPROC)GetOGLProcAddress("glMapBuffer"); _glUnmapBuffer = (PFNGLUNMAPBUFFERPROC)GetOGLProcAddress("glUnmapBuffer"); } else { _glGenBuffers = (PFNGLGENBUFFERSPROC)GetOGLProcAddress("glGenBuffersARB"); _glDeleteBuffers = (PFNGLDELETEBUFFERSPROC)GetOGLProcAddress("glDeleteBuffersARB"); _glBindBuffer = (PFNGLBINDBUFFERPROC)GetOGLProcAddress("glBindBufferARB"); _glBufferData = (PFNGLBUFFERDATAPROC)GetOGLProcAddress("glBufferDataARB"); _glMapBuffer = (PFNGLMAPBUFFERPROC)GetOGLProcAddress("glMapBufferARB"); _glUnmapBuffer = (PFNGLUNMAPBUFFERPROC)GetOGLProcAddress("glUnmapBufferARB"); } return _glGenBuffers != nullptr && _glDeleteBuffers != nullptr && _glBindBuffer != nullptr && _glBufferData != nullptr && _glMapBuffer != nullptr && _glUnmapBuffer != nullptr; } /** Bind vertex array object extension functions. */ static bool BindVBAExtension() { /* The APPLE and ARB variants have different semantics (that don't matter for us). * Successfully getting pointers to one variant doesn't mean it is supported for * the current context. Always check the extension strings as well. */ if (IsOpenGLVersionAtLeast(3, 0) || IsOpenGLExtensionSupported("GL_ARB_vertex_array_object")) { _glGenVertexArrays = (PFNGLGENVERTEXARRAYSPROC)GetOGLProcAddress("glGenVertexArrays"); _glDeleteVertexArrays = (PFNGLDELETEVERTEXARRAYSPROC)GetOGLProcAddress("glDeleteVertexArrays"); _glBindVertexArray = (PFNGLBINDVERTEXARRAYPROC)GetOGLProcAddress("glBindVertexArray"); } else if (IsOpenGLExtensionSupported("GL_APPLE_vertex_array_object")) { _glGenVertexArrays = (PFNGLGENVERTEXARRAYSPROC)GetOGLProcAddress("glGenVertexArraysAPPLE"); _glDeleteVertexArrays = (PFNGLDELETEVERTEXARRAYSPROC)GetOGLProcAddress("glDeleteVertexArraysAPPLE"); _glBindVertexArray = (PFNGLBINDVERTEXARRAYPROC)GetOGLProcAddress("glBindVertexArrayAPPLE"); } return _glGenVertexArrays != nullptr && _glDeleteVertexArrays != nullptr && _glBindVertexArray != nullptr; } /** Bind extension functions for shader support. */ static bool BindShaderExtensions() { if (IsOpenGLVersionAtLeast(2, 0)) { _glCreateProgram = (PFNGLCREATEPROGRAMPROC)GetOGLProcAddress("glCreateProgram"); _glDeleteProgram = (PFNGLDELETEPROGRAMPROC)GetOGLProcAddress("glDeleteProgram"); _glLinkProgram = (PFNGLLINKPROGRAMPROC)GetOGLProcAddress("glLinkProgram"); _glUseProgram = (PFNGLUSEPROGRAMPROC)GetOGLProcAddress("glUseProgram"); _glGetProgramiv = (PFNGLGETPROGRAMIVPROC)GetOGLProcAddress("glGetProgramiv"); _glGetProgramInfoLog = (PFNGLGETPROGRAMINFOLOGPROC)GetOGLProcAddress("glGetProgramInfoLog"); _glCreateShader = (PFNGLCREATESHADERPROC)GetOGLProcAddress("glCreateShader"); _glDeleteShader = (PFNGLDELETESHADERPROC)GetOGLProcAddress("glDeleteShader"); _glShaderSource = (PFNGLSHADERSOURCEPROC)GetOGLProcAddress("glShaderSource"); _glCompileShader = (PFNGLCOMPILESHADERPROC)GetOGLProcAddress("glCompileShader"); _glAttachShader = (PFNGLATTACHSHADERPROC)GetOGLProcAddress("glAttachShader"); _glGetShaderiv = (PFNGLGETSHADERIVPROC)GetOGLProcAddress("glGetShaderiv"); _glGetShaderInfoLog = (PFNGLGETSHADERINFOLOGPROC)GetOGLProcAddress("glGetShaderInfoLog"); _glGetUniformLocation = (PFNGLGETUNIFORMLOCATIONPROC)GetOGLProcAddress("glGetUniformLocation"); _glUniform1i = (PFNGLUNIFORM1IPROC)GetOGLProcAddress("glUniform1i"); _glGetAttribLocation = (PFNGLGETATTRIBLOCATIONPROC)GetOGLProcAddress("glGetAttribLocation"); _glEnableVertexAttribArray = (PFNGLENABLEVERTEXATTRIBARRAYPROC)GetOGLProcAddress("glEnableVertexAttribArray"); _glDisableVertexAttribArray = (PFNGLDISABLEVERTEXATTRIBARRAYPROC)GetOGLProcAddress("glDisableVertexAttribArray"); _glVertexAttribPointer = (PFNGLVERTEXATTRIBPOINTERARBPROC)GetOGLProcAddress("glVertexAttribPointer"); } else { /* In the ARB extension programs and shaders are in the same object space. */ _glCreateProgram = (PFNGLCREATEPROGRAMPROC)GetOGLProcAddress("glCreateProgramObjectARB"); _glDeleteProgram = (PFNGLDELETEPROGRAMPROC)GetOGLProcAddress("glDeleteObjectARB"); _glLinkProgram = (PFNGLLINKPROGRAMPROC)GetOGLProcAddress("glLinkProgramARB"); _glUseProgram = (PFNGLUSEPROGRAMPROC)GetOGLProcAddress("glUseProgramObjectARB"); _glGetProgramiv = (PFNGLGETPROGRAMIVPROC)GetOGLProcAddress("glGetObjectParameterivARB"); _glGetProgramInfoLog = (PFNGLGETPROGRAMINFOLOGPROC)GetOGLProcAddress("glGetInfoLogARB"); _glCreateShader = (PFNGLCREATESHADERPROC)GetOGLProcAddress("glCreateShaderObjectARB"); _glDeleteShader = (PFNGLDELETESHADERPROC)GetOGLProcAddress("glDeleteObjectARB"); _glShaderSource = (PFNGLSHADERSOURCEPROC)GetOGLProcAddress("glShaderSourceARB"); _glCompileShader = (PFNGLCOMPILESHADERPROC)GetOGLProcAddress("glCompileShaderARB"); _glAttachShader = (PFNGLATTACHSHADERPROC)GetOGLProcAddress("glAttachObjectARB"); _glGetShaderiv = (PFNGLGETSHADERIVPROC)GetOGLProcAddress("glGetObjectParameterivARB"); _glGetShaderInfoLog = (PFNGLGETSHADERINFOLOGPROC)GetOGLProcAddress("glGetInfoLogARB"); _glGetUniformLocation = (PFNGLGETUNIFORMLOCATIONPROC)GetOGLProcAddress("glGetUniformLocationARB"); _glUniform1i = (PFNGLUNIFORM1IPROC)GetOGLProcAddress("glUniform1iARB"); _glGetAttribLocation = (PFNGLGETATTRIBLOCATIONPROC)GetOGLProcAddress("glGetAttribLocationARB"); _glEnableVertexAttribArray = (PFNGLENABLEVERTEXATTRIBARRAYPROC)GetOGLProcAddress("glEnableVertexAttribArrayARB"); _glDisableVertexAttribArray = (PFNGLDISABLEVERTEXATTRIBARRAYPROC)GetOGLProcAddress("glDisableVertexAttribArrayARB"); _glVertexAttribPointer = (PFNGLVERTEXATTRIBPOINTERARBPROC)GetOGLProcAddress("glVertexAttribPointerARB"); } /* Bind functions only needed when using GLSL 1.50 shaders. */ if (IsOpenGLVersionAtLeast(3, 0)) { _glBindFragDataLocation = (PFNGLBINDFRAGDATALOCATIONPROC)GetOGLProcAddress("glBindFragDataLocation"); } else if (IsOpenGLExtensionSupported("GL_EXT_gpu_shader4")) { _glBindFragDataLocation = (PFNGLBINDFRAGDATALOCATIONPROC)GetOGLProcAddress("glBindFragDataLocationEXT"); } else { _glBindFragDataLocation = nullptr; } return _glCreateProgram != nullptr && _glDeleteProgram != nullptr && _glLinkProgram != nullptr && _glGetProgramiv != nullptr && _glGetProgramInfoLog != nullptr && _glCreateShader != nullptr && _glDeleteShader != nullptr && _glShaderSource != nullptr && _glCompileShader != nullptr && _glAttachShader != nullptr && _glGetShaderiv != nullptr && _glGetShaderInfoLog != nullptr && _glGetUniformLocation != nullptr && _glUniform1i != nullptr && _glGetAttribLocation != nullptr && _glEnableVertexAttribArray != nullptr && _glDisableVertexAttribArray != nullptr && _glVertexAttribPointer != nullptr; } /** Callback to receive OpenGL debug messages. */ void APIENTRY DebugOutputCallback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar *message, const void *userParam) { /* Make severity human readable. */ const char *severity_str = ""; switch (severity) { case GL_DEBUG_SEVERITY_HIGH: severity_str = "high"; break; case GL_DEBUG_SEVERITY_MEDIUM: severity_str = "medium"; break; case GL_DEBUG_SEVERITY_LOW: severity_str = "low"; break; } /* Make type human readable.*/ const char *type_str = "Other"; switch (type) { case GL_DEBUG_TYPE_ERROR: type_str = "Error"; break; case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR: type_str = "Deprecated"; break; case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR: type_str = "Undefined behaviour"; break; case GL_DEBUG_TYPE_PERFORMANCE: type_str = "Performance"; break; case GL_DEBUG_TYPE_PORTABILITY: type_str = "Portability"; break; } DEBUG(driver, 6, "OpenGL: %s (%s) - %s", type_str, severity_str, message); } /** Enable OpenGL debug messages if supported. */ void SetupDebugOutput() { #ifndef NO_DEBUG_MESSAGES if (_debug_driver_level < 6) return; if (IsOpenGLVersionAtLeast(4, 3)) { _glDebugMessageControl = (PFNGLDEBUGMESSAGECONTROLPROC)GetOGLProcAddress("glDebugMessageControl"); _glDebugMessageCallback = (PFNGLDEBUGMESSAGECALLBACKPROC)GetOGLProcAddress("glDebugMessageCallback"); } else if (IsOpenGLExtensionSupported("GL_ARB_debug_output")) { _glDebugMessageControl = (PFNGLDEBUGMESSAGECONTROLPROC)GetOGLProcAddress("glDebugMessageControlARB"); _glDebugMessageCallback = (PFNGLDEBUGMESSAGECALLBACKPROC)GetOGLProcAddress("glDebugMessageCallbackARB"); } if (_glDebugMessageControl != nullptr && _glDebugMessageCallback != nullptr) { /* Enable debug output. As synchronous debug output costs performance, we only enable it with a high debug level. */ glEnable(GL_DEBUG_OUTPUT); if (_debug_driver_level >= 8) glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS); _glDebugMessageCallback(&DebugOutputCallback, nullptr); /* Enable all messages on highest debug level.*/ _glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DONT_CARE, 0, nullptr, _debug_driver_level >= 9 ? GL_TRUE : GL_FALSE); /* Get debug messages for errors and undefined/deprecated behaviour. */ _glDebugMessageControl(GL_DONT_CARE, GL_DEBUG_TYPE_ERROR, GL_DONT_CARE, 0, nullptr, GL_TRUE); _glDebugMessageControl(GL_DONT_CARE, GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR, GL_DONT_CARE, 0, nullptr, GL_TRUE); _glDebugMessageControl(GL_DONT_CARE, GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR, GL_DONT_CARE, 0, nullptr, GL_TRUE); } #endif } /** * Create and initialize the singleton back-end class. * @param get_proc Callback to get an OpenGL function from the OS driver. * @return nullptr on success, error message otherwise. */ /* static */ const char *OpenGLBackend::Create(GetOGLProcAddressProc get_proc) { if (OpenGLBackend::instance != nullptr) OpenGLBackend::Destroy(); GetOGLProcAddress = get_proc; OpenGLBackend::instance = new OpenGLBackend(); return OpenGLBackend::instance->Init(); } /** * Free resources and destroy singleton back-end class. */ /* static */ void OpenGLBackend::Destroy() { delete OpenGLBackend::instance; OpenGLBackend::instance = nullptr; } /** * Construct OpenGL back-end class. */ OpenGLBackend::OpenGLBackend() { } /** * Free allocated resources. */ OpenGLBackend::~OpenGLBackend() { if (_glDeleteProgram != nullptr) { _glDeleteProgram(this->vid_program); _glDeleteProgram(this->pal_program); } if (_glDeleteVertexArrays != nullptr) _glDeleteVertexArrays(1, &this->vao_quad); if (_glDeleteBuffers != nullptr) { _glDeleteBuffers(1, &this->vbo_quad); _glDeleteBuffers(1, &this->vid_pbo); } glDeleteTextures(1, &this->vid_texture); glDeleteTextures(1, &this->pal_texture); } /** * Check for the needed OpenGL functionality and allocate all resources. * @return Error string or nullptr if successful. */ const char *OpenGLBackend::Init() { /* Always query the supported OpenGL version as the current context might have changed. */ const char *ver = (const char *)glGetString(GL_VERSION); const char *vend = (const char *)glGetString(GL_VENDOR); const char *renderer = (const char *)glGetString(GL_RENDERER); if (ver == nullptr || vend == nullptr || renderer == nullptr) return "OpenGL not supported"; DEBUG(driver, 1, "OpenGL driver: %s - %s (%s)", vend, renderer, ver); const char *minor = strchr(ver, '.'); _gl_major_ver = atoi(ver); _gl_minor_ver = minor != nullptr ? atoi(minor + 1) : 0; SetupDebugOutput(); /* OpenGL 1.3 is the absolute minimum. */ if (!IsOpenGLVersionAtLeast(1, 3)) return "OpenGL version >= 1.3 required"; /* Check for non-power-of-two texture support. */ if (!IsOpenGLVersionAtLeast(2, 0) && !IsOpenGLExtensionSupported("GL_ARB_texture_non_power_of_two")) return "Non-power-of-two textures not supported"; /* Check for single element texture formats. */ if (!IsOpenGLVersionAtLeast(3, 0) && !IsOpenGLExtensionSupported("GL_ARB_texture_rg")) return "Single element texture formats not supported"; if (!BindTextureExtensions()) return "Failed to bind texture extension functions"; /* Check for vertex buffer objects. */ if (!IsOpenGLVersionAtLeast(1, 5) && !IsOpenGLExtensionSupported("ARB_vertex_buffer_object")) return "Vertex buffer objects not supported"; if (!BindVBOExtension()) return "Failed to bind VBO extension functions"; /* Check for pixel buffer objects. */ if (!IsOpenGLVersionAtLeast(2, 1) && !IsOpenGLExtensionSupported("GL_ARB_pixel_buffer_object")) return "Pixel buffer objects not supported"; /* Check for vertex array objects. */ if (!IsOpenGLVersionAtLeast(3, 0) && (!IsOpenGLExtensionSupported("GL_ARB_vertex_array_object") || !IsOpenGLExtensionSupported("GL_APPLE_vertex_array_object"))) return "Vertex array objects not supported"; if (!BindVBAExtension()) return "Failed to bind VBA extension functions"; /* Check for shader objects. */ if (!IsOpenGLVersionAtLeast(2, 0) && (!IsOpenGLExtensionSupported("GL_ARB_shader_objects") || !IsOpenGLExtensionSupported("GL_ARB_fragment_shader") || !IsOpenGLExtensionSupported("GL_ARB_vertex_shader"))) return "No shader support"; if (!BindShaderExtensions()) return "Failed to bind shader extension functions"; if (IsOpenGLVersionAtLeast(3, 2) && _glBindFragDataLocation == nullptr) return "OpenGL claims to support version 3.2 but doesn't have glBindFragDataLocation"; DEBUG(driver, 2, "OpenGL shading language version: %s", (const char *)glGetString(GL_SHADING_LANGUAGE_VERSION)); if (!this->InitShaders()) return "Failed to initialize shaders"; /* Setup video buffer texture. */ glGenTextures(1, &this->vid_texture); glBindTexture(GL_TEXTURE_2D, this->vid_texture); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glBindTexture(GL_TEXTURE_2D, 0); if (glGetError() != GL_NO_ERROR) return "Can't generate video buffer texture"; /* Setup palette texture. */ glGenTextures(1, &this->pal_texture); glBindTexture(GL_TEXTURE_1D, this->pal_texture); glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAX_LEVEL, 0); glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexImage1D(GL_TEXTURE_1D, 0, GL_RGBA8, 256, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr); glBindTexture(GL_TEXTURE_1D, 0); if (glGetError() != GL_NO_ERROR) return "Can't generate palette lookup texture"; /* Bind uniforms in RGB rendering shader program. */ GLint tex_location = _glGetUniformLocation(this->vid_program, "colour_tex"); GLint palette_location = _glGetUniformLocation(this->vid_program, "palette"); _glUseProgram(this->vid_program); _glUniform1i(tex_location, 0); // Texture unit 0. _glUniform1i(palette_location, 1); // Texture unit 1. /* Bind uniforms in palette rendering shader program. */ tex_location = _glGetUniformLocation(this->pal_program, "colour_tex"); palette_location = _glGetUniformLocation(this->pal_program, "palette"); _glUseProgram(this->pal_program); _glUniform1i(tex_location, 0); // Texture unit 0. _glUniform1i(palette_location, 1); // Texture unit 1. /* Create pixel buffer object as video buffer storage. */ _glGenBuffers(1, &this->vid_pbo); _glBindBuffer(GL_PIXEL_UNPACK_BUFFER, this->vid_pbo); if (glGetError() != GL_NO_ERROR) return "Can't allocate pixel buffer for video buffer"; /* Prime vertex buffer with a full-screen quad and store * the corresponding state in a vertex array object. */ static const Simple2DVertex vert_array[] = { // x y u v { 1.f, -1.f, 1.f, 1.f }, { 1.f, 1.f, 1.f, 0.f }, { -1.f, -1.f, 0.f, 1.f }, { -1.f, 1.f, 0.f, 0.f }, }; /* Create VAO. */ _glGenVertexArrays(1, &this->vao_quad); _glBindVertexArray(this->vao_quad); /* Create and fill VBO. */ _glGenBuffers(1, &this->vbo_quad); _glBindBuffer(GL_ARRAY_BUFFER, this->vbo_quad); _glBufferData(GL_ARRAY_BUFFER, sizeof(vert_array), vert_array, GL_STATIC_DRAW); if (glGetError() != GL_NO_ERROR) return "Can't generate VBO for fullscreen quad"; /* Set vertex state. */ GLint loc_position = _glGetAttribLocation(this->vid_program, "position"); GLint colour_position = _glGetAttribLocation(this->vid_program, "colour_uv"); _glEnableVertexAttribArray(loc_position); _glEnableVertexAttribArray(colour_position); _glVertexAttribPointer(loc_position, 2, GL_FLOAT, GL_FALSE, sizeof(Simple2DVertex), (GLvoid *)offsetof(Simple2DVertex, x)); _glVertexAttribPointer(colour_position, 2, GL_FLOAT, GL_FALSE, sizeof(Simple2DVertex), (GLvoid *)offsetof(Simple2DVertex, u)); _glBindVertexArray(0); glClearColor(0.0f, 0.0f, 0.0f, 1.0f); glDisable(GL_DEPTH_TEST); (void)glGetError(); // Clear errors. return nullptr; } /** * Check a shader for compilation errors and log them if necessary. * @param shader Shader to check. * @return True if the shader is valid. */ static bool VerifyShader(GLuint shader) { static ReusableBuffer log_buf; GLint result = GL_FALSE; _glGetShaderiv(shader, GL_COMPILE_STATUS, &result); /* Output log if there is one. */ GLint log_len = 0; _glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &log_len); if (log_len > 0) { _glGetShaderInfoLog(shader, log_len, nullptr, log_buf.Allocate(log_len)); DEBUG(driver, result != GL_TRUE ? 0 : 2, "%s", log_buf.GetBuffer()); // Always print on failure. } return result == GL_TRUE; } /** * Check a program for link errors and log them if necessary. * @param program Program to check. * @return True if the program is valid. */ static bool VerifyProgram(GLuint program) { static ReusableBuffer log_buf; GLint result = GL_FALSE; _glGetProgramiv(program, GL_LINK_STATUS, &result); /* Output log if there is one. */ GLint log_len = 0; _glGetProgramiv(program, GL_INFO_LOG_LENGTH, &log_len); if (log_len > 0) { _glGetProgramInfoLog(program, log_len, nullptr, log_buf.Allocate(log_len)); DEBUG(driver, result != GL_TRUE ? 0 : 2, "%s", log_buf.GetBuffer()); // Always print on failure. } return result == GL_TRUE; } /** * Create all needed shader programs. * @return True if successful, false otherwise. */ bool OpenGLBackend::InitShaders() { const char *ver = (const char *)glGetString(GL_SHADING_LANGUAGE_VERSION); if (ver == nullptr) return false; int glsl_major = ver[0] - '0'; int glsl_minor = ver[2] - '0'; bool glsl_150 = (IsOpenGLVersionAtLeast(3, 2) || glsl_major > 1 || (glsl_major == 1 && glsl_minor >= 5)) && _glBindFragDataLocation != nullptr; /* Create vertex shader. */ GLuint vert_shader = _glCreateShader(GL_VERTEX_SHADER); _glShaderSource(vert_shader, glsl_150 ? lengthof(_vertex_shader_direct_150) : lengthof(_vertex_shader_direct), glsl_150 ? _vertex_shader_direct_150 : _vertex_shader_direct, nullptr); _glCompileShader(vert_shader); if (!VerifyShader(vert_shader)) return false; /* Create fragment shader for plain RGBA. */ GLuint frag_shader_rgb = _glCreateShader(GL_FRAGMENT_SHADER); _glShaderSource(frag_shader_rgb, glsl_150 ? lengthof(_frag_shader_direct_150) : lengthof(_frag_shader_direct), glsl_150 ? _frag_shader_direct_150 : _frag_shader_direct, nullptr); _glCompileShader(frag_shader_rgb); if (!VerifyShader(frag_shader_rgb)) return false; /* Create fragment shader for paletted only. */ GLuint frag_shader_pal = _glCreateShader(GL_FRAGMENT_SHADER); _glShaderSource(frag_shader_pal, glsl_150 ? lengthof(_frag_shader_palette_150) : lengthof(_frag_shader_palette), glsl_150 ? _frag_shader_palette_150 : _frag_shader_palette, nullptr); _glCompileShader(frag_shader_pal); if (!VerifyShader(frag_shader_pal)) return false; /* Link shaders to program. */ this->vid_program = _glCreateProgram(); _glAttachShader(this->vid_program, vert_shader); _glAttachShader(this->vid_program, frag_shader_rgb); this->pal_program = _glCreateProgram(); _glAttachShader(this->pal_program, vert_shader); _glAttachShader(this->pal_program, frag_shader_pal); if (glsl_150) { /* Bind fragment shader outputs. */ _glBindFragDataLocation(this->vid_program, 0, "colour"); _glBindFragDataLocation(this->pal_program, 0, "colour"); } _glLinkProgram(this->vid_program); if (!VerifyProgram(this->vid_program)) return false; _glLinkProgram(this->pal_program); if (!VerifyProgram(this->pal_program)) return false; _glDeleteShader(vert_shader); _glDeleteShader(frag_shader_rgb); _glDeleteShader(frag_shader_pal); return true; } /** * Change the size of the drawing window and allocate matching resources. * @param w New width of the window. * @param h New height of the window. * @param force Recreate resources even if size didn't change. * @param False if nothing had to be done, true otherwise. */ bool OpenGLBackend::Resize(int w, int h, bool force) { if (!force && _screen.width == w && _screen.height == h) return false; int bpp = BlitterFactory::GetCurrentBlitter()->GetScreenDepth(); int pitch = bpp != 32 ? Align(w, 4) : w; glViewport(0, 0, w, h); /* Re-allocate video buffer texture and backing store. */ _glBindBuffer(GL_PIXEL_UNPACK_BUFFER, this->vid_pbo); _glBufferData(GL_PIXEL_UNPACK_BUFFER, pitch * h * bpp / 8, nullptr, GL_DYNAMIC_READ); // Buffer content has to persist from frame to frame and is read back by the blitter, which means a READ usage hint. _glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0); _glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, this->vid_texture); switch (bpp) { case 8: glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, w, h, 0, GL_RED, GL_UNSIGNED_BYTE, nullptr); break; default: glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, w, h, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, nullptr); break; } glBindTexture(GL_TEXTURE_2D, 0); /* Set new viewport. */ _screen.height = h; _screen.width = w; _screen.pitch = pitch; _screen.dst_ptr = nullptr; return true; } /** * Update the stored palette. * @param pal Palette array with at least 256 elements. * @param first First entry to update. * @param length Number of entries to update. */ void OpenGLBackend::UpdatePalette(const Colour *pal, uint first, uint length) { assert(first + length <= 256); glPixelStorei(GL_UNPACK_ROW_LENGTH, 0); _glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0); _glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_1D, this->pal_texture); glTexSubImage1D(GL_TEXTURE_1D, 0, first, length, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, pal + first); } /** * Render video buffer to the screen. */ void OpenGLBackend::Paint() { glClear(GL_COLOR_BUFFER_BIT); /* Blit video buffer to screen. */ _glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, this->vid_texture); _glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_1D, this->pal_texture); _glUseProgram(BlitterFactory::GetCurrentBlitter()->GetScreenDepth() == 8 ? this->pal_program : this->vid_program); _glBindVertexArray(this->vao_quad); glDrawArrays(GL_TRIANGLE_STRIP, 0, 4); } /** * Get a pointer to the memory for the video driver to draw to. * @return Pointer to draw on. */ void *OpenGLBackend::GetVideoBuffer() { _glBindBuffer(GL_PIXEL_UNPACK_BUFFER, this->vid_pbo); return _glMapBuffer(GL_PIXEL_UNPACK_BUFFER, GL_READ_WRITE); } /** * Update video buffer texture after the video buffer was filled. * @param update_rect Rectangle encompassing the dirty region of the video buffer. */ void OpenGLBackend::ReleaseVideoBuffer(const Rect &update_rect) { assert(this->vid_pbo != 0); _glBindBuffer(GL_PIXEL_UNPACK_BUFFER, this->vid_pbo); _glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER); /* Update changed rect of the video buffer texture. */ if (!IsEmptyRect(update_rect)) { _glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, this->vid_texture); glPixelStorei(GL_UNPACK_ROW_LENGTH, _screen.pitch); switch (BlitterFactory::GetCurrentBlitter()->GetScreenDepth()) { case 8: glTexSubImage2D(GL_TEXTURE_2D, 0, update_rect.left, update_rect.top, update_rect.right - update_rect.left, update_rect.bottom - update_rect.top, GL_RED, GL_UNSIGNED_BYTE, (GLvoid *)(size_t)(update_rect.top * _screen.pitch + update_rect.left)); break; default: glTexSubImage2D(GL_TEXTURE_2D, 0, update_rect.left, update_rect.top, update_rect.right - update_rect.left, update_rect.bottom - update_rect.top, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, (GLvoid *)(size_t)(update_rect.top * _screen.pitch * 4 + update_rect.left * 4)); break; } } }