diff options
Diffstat (limited to 'libs/glfw-3.3.8/src/context.c')
| -rw-r--r-- | libs/glfw-3.3.8/src/context.c | 758 |
1 files changed, 758 insertions, 0 deletions
diff --git a/libs/glfw-3.3.8/src/context.c b/libs/glfw-3.3.8/src/context.c new file mode 100644 index 0000000..d86e0fa --- /dev/null +++ b/libs/glfw-3.3.8/src/context.c @@ -0,0 +1,758 @@ +//======================================================================== +// GLFW 3.3 - www.glfw.org +//------------------------------------------------------------------------ +// Copyright (c) 2002-2006 Marcus Geelnard +// Copyright (c) 2006-2016 Camilla Löwy <elmindreda@glfw.org> +// +// This software is provided 'as-is', without any express or implied +// warranty. In no event will the authors be held liable for any damages +// arising from the use of this software. +// +// Permission is granted to anyone to use this software for any purpose, +// including commercial applications, and to alter it and redistribute it +// freely, subject to the following restrictions: +// +// 1. The origin of this software must not be misrepresented; you must not +// claim that you wrote the original software. If you use this software +// in a product, an acknowledgment in the product documentation would +// be appreciated but is not required. +// +// 2. Altered source versions must be plainly marked as such, and must not +// be misrepresented as being the original software. +// +// 3. This notice may not be removed or altered from any source +// distribution. +// +//======================================================================== +// Please use C89 style variable declarations in this file because VS 2010 +//======================================================================== + +#include "internal.h" + +#include <assert.h> +#include <stdio.h> +#include <string.h> +#include <limits.h> +#include <stdio.h> + + +////////////////////////////////////////////////////////////////////////// +////// GLFW internal API ////// +////////////////////////////////////////////////////////////////////////// + +// Checks whether the desired context attributes are valid +// +// This function checks things like whether the specified client API version +// exists and whether all relevant options have supported and non-conflicting +// values +// +GLFWbool _glfwIsValidContextConfig(const _GLFWctxconfig* ctxconfig) +{ + if (ctxconfig->share) + { + if (ctxconfig->client == GLFW_NO_API || + ctxconfig->share->context.client == GLFW_NO_API) + { + _glfwInputError(GLFW_NO_WINDOW_CONTEXT, NULL); + return GLFW_FALSE; + } + } + + if (ctxconfig->source != GLFW_NATIVE_CONTEXT_API && + ctxconfig->source != GLFW_EGL_CONTEXT_API && + ctxconfig->source != GLFW_OSMESA_CONTEXT_API) + { + _glfwInputError(GLFW_INVALID_ENUM, + "Invalid context creation API 0x%08X", + ctxconfig->source); + return GLFW_FALSE; + } + + if (ctxconfig->client != GLFW_NO_API && + ctxconfig->client != GLFW_OPENGL_API && + ctxconfig->client != GLFW_OPENGL_ES_API) + { + _glfwInputError(GLFW_INVALID_ENUM, + "Invalid client API 0x%08X", + ctxconfig->client); + return GLFW_FALSE; + } + + if (ctxconfig->client == GLFW_OPENGL_API) + { + if ((ctxconfig->major < 1 || ctxconfig->minor < 0) || + (ctxconfig->major == 1 && ctxconfig->minor > 5) || + (ctxconfig->major == 2 && ctxconfig->minor > 1) || + (ctxconfig->major == 3 && ctxconfig->minor > 3)) + { + // OpenGL 1.0 is the smallest valid version + // OpenGL 1.x series ended with version 1.5 + // OpenGL 2.x series ended with version 2.1 + // OpenGL 3.x series ended with version 3.3 + // For now, let everything else through + + _glfwInputError(GLFW_INVALID_VALUE, + "Invalid OpenGL version %i.%i", + ctxconfig->major, ctxconfig->minor); + return GLFW_FALSE; + } + + if (ctxconfig->profile) + { + if (ctxconfig->profile != GLFW_OPENGL_CORE_PROFILE && + ctxconfig->profile != GLFW_OPENGL_COMPAT_PROFILE) + { + _glfwInputError(GLFW_INVALID_ENUM, + "Invalid OpenGL profile 0x%08X", + ctxconfig->profile); + return GLFW_FALSE; + } + + if (ctxconfig->major <= 2 || + (ctxconfig->major == 3 && ctxconfig->minor < 2)) + { + // Desktop OpenGL context profiles are only defined for version 3.2 + // and above + + _glfwInputError(GLFW_INVALID_VALUE, + "Context profiles are only defined for OpenGL version 3.2 and above"); + return GLFW_FALSE; + } + } + + if (ctxconfig->forward && ctxconfig->major <= 2) + { + // Forward-compatible contexts are only defined for OpenGL version 3.0 and above + _glfwInputError(GLFW_INVALID_VALUE, + "Forward-compatibility is only defined for OpenGL version 3.0 and above"); + return GLFW_FALSE; + } + } + else if (ctxconfig->client == GLFW_OPENGL_ES_API) + { + if (ctxconfig->major < 1 || ctxconfig->minor < 0 || + (ctxconfig->major == 1 && ctxconfig->minor > 1) || + (ctxconfig->major == 2 && ctxconfig->minor > 0)) + { + // OpenGL ES 1.0 is the smallest valid version + // OpenGL ES 1.x series ended with version 1.1 + // OpenGL ES 2.x series ended with version 2.0 + // For now, let everything else through + + _glfwInputError(GLFW_INVALID_VALUE, + "Invalid OpenGL ES version %i.%i", + ctxconfig->major, ctxconfig->minor); + return GLFW_FALSE; + } + } + + if (ctxconfig->robustness) + { + if (ctxconfig->robustness != GLFW_NO_RESET_NOTIFICATION && + ctxconfig->robustness != GLFW_LOSE_CONTEXT_ON_RESET) + { + _glfwInputError(GLFW_INVALID_ENUM, + "Invalid context robustness mode 0x%08X", + ctxconfig->robustness); + return GLFW_FALSE; + } + } + + if (ctxconfig->release) + { + if (ctxconfig->release != GLFW_RELEASE_BEHAVIOR_NONE && + ctxconfig->release != GLFW_RELEASE_BEHAVIOR_FLUSH) + { + _glfwInputError(GLFW_INVALID_ENUM, + "Invalid context release behavior 0x%08X", + ctxconfig->release); + return GLFW_FALSE; + } + } + + return GLFW_TRUE; +} + +// Chooses the framebuffer config that best matches the desired one +// +const _GLFWfbconfig* _glfwChooseFBConfig(const _GLFWfbconfig* desired, + const _GLFWfbconfig* alternatives, + unsigned int count) +{ + unsigned int i; + unsigned int missing, leastMissing = UINT_MAX; + unsigned int colorDiff, leastColorDiff = UINT_MAX; + unsigned int extraDiff, leastExtraDiff = UINT_MAX; + const _GLFWfbconfig* current; + const _GLFWfbconfig* closest = NULL; + + for (i = 0; i < count; i++) + { + current = alternatives + i; + + if (desired->stereo > 0 && current->stereo == 0) + { + // Stereo is a hard constraint + continue; + } + + // Count number of missing buffers + { + missing = 0; + + if (desired->alphaBits > 0 && current->alphaBits == 0) + missing++; + + if (desired->depthBits > 0 && current->depthBits == 0) + missing++; + + if (desired->stencilBits > 0 && current->stencilBits == 0) + missing++; + + if (desired->auxBuffers > 0 && + current->auxBuffers < desired->auxBuffers) + { + missing += desired->auxBuffers - current->auxBuffers; + } + + if (desired->samples > 0 && current->samples == 0) + { + // Technically, several multisampling buffers could be + // involved, but that's a lower level implementation detail and + // not important to us here, so we count them as one + missing++; + } + + if (desired->transparent != current->transparent) + missing++; + } + + // These polynomials make many small channel size differences matter + // less than one large channel size difference + + // Calculate color channel size difference value + { + colorDiff = 0; + + if (desired->redBits != GLFW_DONT_CARE) + { + colorDiff += (desired->redBits - current->redBits) * + (desired->redBits - current->redBits); + } + + if (desired->greenBits != GLFW_DONT_CARE) + { + colorDiff += (desired->greenBits - current->greenBits) * + (desired->greenBits - current->greenBits); + } + + if (desired->blueBits != GLFW_DONT_CARE) + { + colorDiff += (desired->blueBits - current->blueBits) * + (desired->blueBits - current->blueBits); + } + } + + // Calculate non-color channel size difference value + { + extraDiff = 0; + + if (desired->alphaBits != GLFW_DONT_CARE) + { + extraDiff += (desired->alphaBits - current->alphaBits) * + (desired->alphaBits - current->alphaBits); + } + + if (desired->depthBits != GLFW_DONT_CARE) + { + extraDiff += (desired->depthBits - current->depthBits) * + (desired->depthBits - current->depthBits); + } + + if (desired->stencilBits != GLFW_DONT_CARE) + { + extraDiff += (desired->stencilBits - current->stencilBits) * + (desired->stencilBits - current->stencilBits); + } + + if (desired->accumRedBits != GLFW_DONT_CARE) + { + extraDiff += (desired->accumRedBits - current->accumRedBits) * + (desired->accumRedBits - current->accumRedBits); + } + + if (desired->accumGreenBits != GLFW_DONT_CARE) + { + extraDiff += (desired->accumGreenBits - current->accumGreenBits) * + (desired->accumGreenBits - current->accumGreenBits); + } + + if (desired->accumBlueBits != GLFW_DONT_CARE) + { + extraDiff += (desired->accumBlueBits - current->accumBlueBits) * + (desired->accumBlueBits - current->accumBlueBits); + } + + if (desired->accumAlphaBits != GLFW_DONT_CARE) + { + extraDiff += (desired->accumAlphaBits - current->accumAlphaBits) * + (desired->accumAlphaBits - current->accumAlphaBits); + } + + if (desired->samples != GLFW_DONT_CARE) + { + extraDiff += (desired->samples - current->samples) * + (desired->samples - current->samples); + } + + if (desired->sRGB && !current->sRGB) + extraDiff++; + } + + // Figure out if the current one is better than the best one found so far + // Least number of missing buffers is the most important heuristic, + // then color buffer size match and lastly size match for other buffers + + if (missing < leastMissing) + closest = current; + else if (missing == leastMissing) + { + if ((colorDiff < leastColorDiff) || + (colorDiff == leastColorDiff && extraDiff < leastExtraDiff)) + { + closest = current; + } + } + + if (current == closest) + { + leastMissing = missing; + leastColorDiff = colorDiff; + leastExtraDiff = extraDiff; + } + } + + return closest; +} + +// Retrieves the attributes of the current context +// +GLFWbool _glfwRefreshContextAttribs(_GLFWwindow* window, + const _GLFWctxconfig* ctxconfig) +{ + int i; + _GLFWwindow* previous; + const char* version; + const char* prefixes[] = + { + "OpenGL ES-CM ", + "OpenGL ES-CL ", + "OpenGL ES ", + NULL + }; + + window->context.source = ctxconfig->source; + window->context.client = GLFW_OPENGL_API; + + previous = _glfwPlatformGetTls(&_glfw.contextSlot); + glfwMakeContextCurrent((GLFWwindow*) window); + + window->context.GetIntegerv = (PFNGLGETINTEGERVPROC) + window->context.getProcAddress("glGetIntegerv"); + window->context.GetString = (PFNGLGETSTRINGPROC) + window->context.getProcAddress("glGetString"); + if (!window->context.GetIntegerv || !window->context.GetString) + { + _glfwInputError(GLFW_PLATFORM_ERROR, "Entry point retrieval is broken"); + glfwMakeContextCurrent((GLFWwindow*) previous); + return GLFW_FALSE; + } + + version = (const char*) window->context.GetString(GL_VERSION); + if (!version) + { + if (ctxconfig->client == GLFW_OPENGL_API) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "OpenGL version string retrieval is broken"); + } + else + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "OpenGL ES version string retrieval is broken"); + } + + glfwMakeContextCurrent((GLFWwindow*) previous); + return GLFW_FALSE; + } + + for (i = 0; prefixes[i]; i++) + { + const size_t length = strlen(prefixes[i]); + + if (strncmp(version, prefixes[i], length) == 0) + { + version += length; + window->context.client = GLFW_OPENGL_ES_API; + break; + } + } + + if (!sscanf(version, "%d.%d.%d", + &window->context.major, + &window->context.minor, + &window->context.revision)) + { + if (window->context.client == GLFW_OPENGL_API) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "No version found in OpenGL version string"); + } + else + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "No version found in OpenGL ES version string"); + } + + glfwMakeContextCurrent((GLFWwindow*) previous); + return GLFW_FALSE; + } + + if (window->context.major < ctxconfig->major || + (window->context.major == ctxconfig->major && + window->context.minor < ctxconfig->minor)) + { + // The desired OpenGL version is greater than the actual version + // This only happens if the machine lacks {GLX|WGL}_ARB_create_context + // /and/ the user has requested an OpenGL version greater than 1.0 + + // For API consistency, we emulate the behavior of the + // {GLX|WGL}_ARB_create_context extension and fail here + + if (window->context.client == GLFW_OPENGL_API) + { + _glfwInputError(GLFW_VERSION_UNAVAILABLE, + "Requested OpenGL version %i.%i, got version %i.%i", + ctxconfig->major, ctxconfig->minor, + window->context.major, window->context.minor); + } + else + { + _glfwInputError(GLFW_VERSION_UNAVAILABLE, + "Requested OpenGL ES version %i.%i, got version %i.%i", + ctxconfig->major, ctxconfig->minor, + window->context.major, window->context.minor); + } + + glfwMakeContextCurrent((GLFWwindow*) previous); + return GLFW_FALSE; + } + + if (window->context.major >= 3) + { + // OpenGL 3.0+ uses a different function for extension string retrieval + // We cache it here instead of in glfwExtensionSupported mostly to alert + // users as early as possible that their build may be broken + + window->context.GetStringi = (PFNGLGETSTRINGIPROC) + window->context.getProcAddress("glGetStringi"); + if (!window->context.GetStringi) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "Entry point retrieval is broken"); + glfwMakeContextCurrent((GLFWwindow*) previous); + return GLFW_FALSE; + } + } + + if (window->context.client == GLFW_OPENGL_API) + { + // Read back context flags (OpenGL 3.0 and above) + if (window->context.major >= 3) + { + GLint flags; + window->context.GetIntegerv(GL_CONTEXT_FLAGS, &flags); + + if (flags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT) + window->context.forward = GLFW_TRUE; + + if (flags & GL_CONTEXT_FLAG_DEBUG_BIT) + window->context.debug = GLFW_TRUE; + else if (glfwExtensionSupported("GL_ARB_debug_output") && + ctxconfig->debug) + { + // HACK: This is a workaround for older drivers (pre KHR_debug) + // not setting the debug bit in the context flags for + // debug contexts + window->context.debug = GLFW_TRUE; + } + + if (flags & GL_CONTEXT_FLAG_NO_ERROR_BIT_KHR) + window->context.noerror = GLFW_TRUE; + } + + // Read back OpenGL context profile (OpenGL 3.2 and above) + if (window->context.major >= 4 || + (window->context.major == 3 && window->context.minor >= 2)) + { + GLint mask; + window->context.GetIntegerv(GL_CONTEXT_PROFILE_MASK, &mask); + + if (mask & GL_CONTEXT_COMPATIBILITY_PROFILE_BIT) + window->context.profile = GLFW_OPENGL_COMPAT_PROFILE; + else if (mask & GL_CONTEXT_CORE_PROFILE_BIT) + window->context.profile = GLFW_OPENGL_CORE_PROFILE; + else if (glfwExtensionSupported("GL_ARB_compatibility")) + { + // HACK: This is a workaround for the compatibility profile bit + // not being set in the context flags if an OpenGL 3.2+ + // context was created without having requested a specific + // version + window->context.profile = GLFW_OPENGL_COMPAT_PROFILE; + } + } + + // Read back robustness strategy + if (glfwExtensionSupported("GL_ARB_robustness")) + { + // NOTE: We avoid using the context flags for detection, as they are + // only present from 3.0 while the extension applies from 1.1 + + GLint strategy; + window->context.GetIntegerv(GL_RESET_NOTIFICATION_STRATEGY_ARB, + &strategy); + + if (strategy == GL_LOSE_CONTEXT_ON_RESET_ARB) + window->context.robustness = GLFW_LOSE_CONTEXT_ON_RESET; + else if (strategy == GL_NO_RESET_NOTIFICATION_ARB) + window->context.robustness = GLFW_NO_RESET_NOTIFICATION; + } + } + else + { + // Read back robustness strategy + if (glfwExtensionSupported("GL_EXT_robustness")) + { + // NOTE: The values of these constants match those of the OpenGL ARB + // one, so we can reuse them here + + GLint strategy; + window->context.GetIntegerv(GL_RESET_NOTIFICATION_STRATEGY_ARB, + &strategy); + + if (strategy == GL_LOSE_CONTEXT_ON_RESET_ARB) + window->context.robustness = GLFW_LOSE_CONTEXT_ON_RESET; + else if (strategy == GL_NO_RESET_NOTIFICATION_ARB) + window->context.robustness = GLFW_NO_RESET_NOTIFICATION; + } + } + + if (glfwExtensionSupported("GL_KHR_context_flush_control")) + { + GLint behavior; + window->context.GetIntegerv(GL_CONTEXT_RELEASE_BEHAVIOR, &behavior); + + if (behavior == GL_NONE) + window->context.release = GLFW_RELEASE_BEHAVIOR_NONE; + else if (behavior == GL_CONTEXT_RELEASE_BEHAVIOR_FLUSH) + window->context.release = GLFW_RELEASE_BEHAVIOR_FLUSH; + } + + // Clearing the front buffer to black to avoid garbage pixels left over from + // previous uses of our bit of VRAM + { + PFNGLCLEARPROC glClear = (PFNGLCLEARPROC) + window->context.getProcAddress("glClear"); + glClear(GL_COLOR_BUFFER_BIT); + + if (window->doublebuffer) + window->context.swapBuffers(window); + } + + glfwMakeContextCurrent((GLFWwindow*) previous); + return GLFW_TRUE; +} + +// Searches an extension string for the specified extension +// +GLFWbool _glfwStringInExtensionString(const char* string, const char* extensions) +{ + const char* start = extensions; + + for (;;) + { + const char* where; + const char* terminator; + + where = strstr(start, string); + if (!where) + return GLFW_FALSE; + + terminator = where + strlen(string); + if (where == start || *(where - 1) == ' ') + { + if (*terminator == ' ' || *terminator == '\0') + break; + } + + start = terminator; + } + + return GLFW_TRUE; +} + + +////////////////////////////////////////////////////////////////////////// +////// GLFW public API ////// +////////////////////////////////////////////////////////////////////////// + +GLFWAPI void glfwMakeContextCurrent(GLFWwindow* handle) +{ + _GLFWwindow* window = (_GLFWwindow*) handle; + _GLFWwindow* previous; + + _GLFW_REQUIRE_INIT(); + + previous = _glfwPlatformGetTls(&_glfw.contextSlot); + + if (window && window->context.client == GLFW_NO_API) + { + _glfwInputError(GLFW_NO_WINDOW_CONTEXT, + "Cannot make current with a window that has no OpenGL or OpenGL ES context"); + return; + } + + if (previous) + { + if (!window || window->context.source != previous->context.source) + previous->context.makeCurrent(NULL); + } + + if (window) + window->context.makeCurrent(window); +} + +GLFWAPI GLFWwindow* glfwGetCurrentContext(void) +{ + _GLFW_REQUIRE_INIT_OR_RETURN(NULL); + return _glfwPlatformGetTls(&_glfw.contextSlot); +} + +GLFWAPI void glfwSwapBuffers(GLFWwindow* handle) +{ + _GLFWwindow* window = (_GLFWwindow*) handle; + assert(window != NULL); + + _GLFW_REQUIRE_INIT(); + + if (window->context.client == GLFW_NO_API) + { + _glfwInputError(GLFW_NO_WINDOW_CONTEXT, + "Cannot swap buffers of a window that has no OpenGL or OpenGL ES context"); + return; + } + + window->context.swapBuffers(window); +} + +GLFWAPI void glfwSwapInterval(int interval) +{ + _GLFWwindow* window; + + _GLFW_REQUIRE_INIT(); + + window = _glfwPlatformGetTls(&_glfw.contextSlot); + if (!window) + { + _glfwInputError(GLFW_NO_CURRENT_CONTEXT, + "Cannot set swap interval without a current OpenGL or OpenGL ES context"); + return; + } + + window->context.swapInterval(interval); +} + +GLFWAPI int glfwExtensionSupported(const char* extension) +{ + _GLFWwindow* window; + assert(extension != NULL); + + _GLFW_REQUIRE_INIT_OR_RETURN(GLFW_FALSE); + + window = _glfwPlatformGetTls(&_glfw.contextSlot); + if (!window) + { + _glfwInputError(GLFW_NO_CURRENT_CONTEXT, + "Cannot query extension without a current OpenGL or OpenGL ES context"); + return GLFW_FALSE; + } + + if (*extension == '\0') + { + _glfwInputError(GLFW_INVALID_VALUE, "Extension name cannot be an empty string"); + return GLFW_FALSE; + } + + if (window->context.major >= 3) + { + int i; + GLint count; + + // Check if extension is in the modern OpenGL extensions string list + + window->context.GetIntegerv(GL_NUM_EXTENSIONS, &count); + + for (i = 0; i < count; i++) + { + const char* en = (const char*) + window->context.GetStringi(GL_EXTENSIONS, i); + if (!en) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "Extension string retrieval is broken"); + return GLFW_FALSE; + } + + if (strcmp(en, extension) == 0) + return GLFW_TRUE; + } + } + else + { + // Check if extension is in the old style OpenGL extensions string + + const char* extensions = (const char*) + window->context.GetString(GL_EXTENSIONS); + if (!extensions) + { + _glfwInputError(GLFW_PLATFORM_ERROR, + "Extension string retrieval is broken"); + return GLFW_FALSE; + } + + if (_glfwStringInExtensionString(extension, extensions)) + return GLFW_TRUE; + } + + // Check if extension is in the platform-specific string + return window->context.extensionSupported(extension); +} + +GLFWAPI GLFWglproc glfwGetProcAddress(const char* procname) +{ + _GLFWwindow* window; + assert(procname != NULL); + + _GLFW_REQUIRE_INIT_OR_RETURN(NULL); + + window = _glfwPlatformGetTls(&_glfw.contextSlot); + if (!window) + { + _glfwInputError(GLFW_NO_CURRENT_CONTEXT, + "Cannot query entry point without a current OpenGL or OpenGL ES context"); + return NULL; + } + + return window->context.getProcAddress(procname); +} + |