bindings-GLFW-3.1: glfw/src/wgl_context.c
//========================================================================
// GLFW 3.1 WGL - www.glfw.org
//------------------------------------------------------------------------
// Copyright (c) 2002-2006 Marcus Geelnard
// Copyright (c) 2006-2010 Camilla Berglund <elmindreda@elmindreda.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.
//
//========================================================================
#include "internal.h"
#include <stdlib.h>
#include <malloc.h>
#include <assert.h>
// Initialize WGL-specific extensions
// This function is called once before initial context creation, i.e. before
// any WGL extensions could be present. This is done in order to have both
// extension variable clearing and loading in the same place, hopefully
// decreasing the possibility of forgetting to add one without the other.
//
static void initWGLExtensions(_GLFWwindow* window)
{
// This needs to include every function pointer loaded below
window->wgl.SwapIntervalEXT = NULL;
window->wgl.GetPixelFormatAttribivARB = NULL;
window->wgl.GetExtensionsStringARB = NULL;
window->wgl.GetExtensionsStringEXT = NULL;
window->wgl.CreateContextAttribsARB = NULL;
// This needs to include every extension used below except for
// WGL_ARB_extensions_string and WGL_EXT_extensions_string
window->wgl.ARB_multisample = GL_FALSE;
window->wgl.ARB_framebuffer_sRGB = GL_FALSE;
window->wgl.ARB_create_context = GL_FALSE;
window->wgl.ARB_create_context_profile = GL_FALSE;
window->wgl.EXT_create_context_es2_profile = GL_FALSE;
window->wgl.ARB_create_context_robustness = GL_FALSE;
window->wgl.EXT_swap_control = GL_FALSE;
window->wgl.ARB_pixel_format = GL_FALSE;
window->wgl.ARB_context_flush_control = GL_FALSE;
window->wgl.GetExtensionsStringEXT = (PFNWGLGETEXTENSIONSSTRINGEXTPROC)
wglGetProcAddress("wglGetExtensionsStringEXT");
if (!window->wgl.GetExtensionsStringEXT)
{
window->wgl.GetExtensionsStringARB = (PFNWGLGETEXTENSIONSSTRINGARBPROC)
wglGetProcAddress("wglGetExtensionsStringARB");
if (!window->wgl.GetExtensionsStringARB)
return;
}
if (_glfwPlatformExtensionSupported("WGL_ARB_multisample"))
window->wgl.ARB_multisample = GL_TRUE;
if (_glfwPlatformExtensionSupported("WGL_ARB_framebuffer_sRGB"))
window->wgl.ARB_framebuffer_sRGB = GL_TRUE;
if (_glfwPlatformExtensionSupported("WGL_ARB_create_context"))
{
window->wgl.CreateContextAttribsARB = (PFNWGLCREATECONTEXTATTRIBSARBPROC)
wglGetProcAddress("wglCreateContextAttribsARB");
if (window->wgl.CreateContextAttribsARB)
window->wgl.ARB_create_context = GL_TRUE;
}
if (window->wgl.ARB_create_context)
{
if (_glfwPlatformExtensionSupported("WGL_ARB_create_context_profile"))
window->wgl.ARB_create_context_profile = GL_TRUE;
}
if (window->wgl.ARB_create_context &&
window->wgl.ARB_create_context_profile)
{
if (_glfwPlatformExtensionSupported("WGL_EXT_create_context_es2_profile"))
window->wgl.EXT_create_context_es2_profile = GL_TRUE;
}
if (window->wgl.ARB_create_context)
{
if (_glfwPlatformExtensionSupported("WGL_ARB_create_context_robustness"))
window->wgl.ARB_create_context_robustness = GL_TRUE;
}
if (_glfwPlatformExtensionSupported("WGL_EXT_swap_control"))
{
window->wgl.SwapIntervalEXT = (PFNWGLSWAPINTERVALEXTPROC)
wglGetProcAddress("wglSwapIntervalEXT");
if (window->wgl.SwapIntervalEXT)
window->wgl.EXT_swap_control = GL_TRUE;
}
if (_glfwPlatformExtensionSupported("WGL_ARB_pixel_format"))
{
window->wgl.GetPixelFormatAttribivARB = (PFNWGLGETPIXELFORMATATTRIBIVARBPROC)
wglGetProcAddress("wglGetPixelFormatAttribivARB");
if (window->wgl.GetPixelFormatAttribivARB)
window->wgl.ARB_pixel_format = GL_TRUE;
}
if (_glfwPlatformExtensionSupported("WGL_ARB_context_flush_control"))
window->wgl.ARB_context_flush_control = GL_TRUE;
}
// Returns the specified attribute of the specified pixel format
// NOTE: Do not call this unless we have found WGL_ARB_pixel_format
//
static int getPixelFormatAttrib(_GLFWwindow* window, int pixelFormat, int attrib)
{
int value = 0;
if (!window->wgl.GetPixelFormatAttribivARB(window->wgl.dc,
pixelFormat,
0, 1, &attrib, &value))
{
// NOTE: We should probably handle this error somehow
return 0;
}
return value;
}
// Return a list of available and usable framebuffer configs
//
static GLboolean choosePixelFormat(_GLFWwindow* window,
const _GLFWfbconfig* desired,
int* result)
{
_GLFWfbconfig* usableConfigs;
const _GLFWfbconfig* closest;
int i, nativeCount, usableCount;
if (window->wgl.ARB_pixel_format)
{
nativeCount = getPixelFormatAttrib(window,
1,
WGL_NUMBER_PIXEL_FORMATS_ARB);
}
else
{
nativeCount = DescribePixelFormat(window->wgl.dc,
1,
sizeof(PIXELFORMATDESCRIPTOR),
NULL);
}
if (!nativeCount)
{
_glfwInputError(GLFW_API_UNAVAILABLE, "WGL: No pixel formats found");
return GL_FALSE;
}
usableConfigs = calloc(nativeCount, sizeof(_GLFWfbconfig));
usableCount = 0;
for (i = 0; i < nativeCount; i++)
{
const int n = i + 1;
_GLFWfbconfig* u = usableConfigs + usableCount;
if (window->wgl.ARB_pixel_format)
{
// Get pixel format attributes through WGL_ARB_pixel_format
if (!getPixelFormatAttrib(window, n, WGL_SUPPORT_OPENGL_ARB) ||
!getPixelFormatAttrib(window, n, WGL_DRAW_TO_WINDOW_ARB))
{
continue;
}
if (getPixelFormatAttrib(window, n, WGL_PIXEL_TYPE_ARB) !=
WGL_TYPE_RGBA_ARB)
{
continue;
}
if (getPixelFormatAttrib(window, n, WGL_ACCELERATION_ARB) ==
WGL_NO_ACCELERATION_ARB)
{
continue;
}
u->redBits = getPixelFormatAttrib(window, n, WGL_RED_BITS_ARB);
u->greenBits = getPixelFormatAttrib(window, n, WGL_GREEN_BITS_ARB);
u->blueBits = getPixelFormatAttrib(window, n, WGL_BLUE_BITS_ARB);
u->alphaBits = getPixelFormatAttrib(window, n, WGL_ALPHA_BITS_ARB);
u->depthBits = getPixelFormatAttrib(window, n, WGL_DEPTH_BITS_ARB);
u->stencilBits = getPixelFormatAttrib(window, n, WGL_STENCIL_BITS_ARB);
u->accumRedBits = getPixelFormatAttrib(window, n, WGL_ACCUM_RED_BITS_ARB);
u->accumGreenBits = getPixelFormatAttrib(window, n, WGL_ACCUM_GREEN_BITS_ARB);
u->accumBlueBits = getPixelFormatAttrib(window, n, WGL_ACCUM_BLUE_BITS_ARB);
u->accumAlphaBits = getPixelFormatAttrib(window, n, WGL_ACCUM_ALPHA_BITS_ARB);
u->auxBuffers = getPixelFormatAttrib(window, n, WGL_AUX_BUFFERS_ARB);
if (getPixelFormatAttrib(window, n, WGL_STEREO_ARB))
u->stereo = GL_TRUE;
if (getPixelFormatAttrib(window, n, WGL_DOUBLE_BUFFER_ARB))
u->doublebuffer = GL_TRUE;
if (window->wgl.ARB_multisample)
u->samples = getPixelFormatAttrib(window, n, WGL_SAMPLES_ARB);
if (window->wgl.ARB_framebuffer_sRGB)
{
if (getPixelFormatAttrib(window, n, WGL_FRAMEBUFFER_SRGB_CAPABLE_ARB))
u->sRGB = GL_TRUE;
}
}
else
{
PIXELFORMATDESCRIPTOR pfd;
// Get pixel format attributes through old-fashioned PFDs
if (!DescribePixelFormat(window->wgl.dc,
n,
sizeof(PIXELFORMATDESCRIPTOR),
&pfd))
{
continue;
}
if (!(pfd.dwFlags & PFD_DRAW_TO_WINDOW) ||
!(pfd.dwFlags & PFD_SUPPORT_OPENGL))
{
continue;
}
if (!(pfd.dwFlags & PFD_GENERIC_ACCELERATED) &&
(pfd.dwFlags & PFD_GENERIC_FORMAT))
{
continue;
}
if (pfd.iPixelType != PFD_TYPE_RGBA)
continue;
u->redBits = pfd.cRedBits;
u->greenBits = pfd.cGreenBits;
u->blueBits = pfd.cBlueBits;
u->alphaBits = pfd.cAlphaBits;
u->depthBits = pfd.cDepthBits;
u->stencilBits = pfd.cStencilBits;
u->accumRedBits = pfd.cAccumRedBits;
u->accumGreenBits = pfd.cAccumGreenBits;
u->accumBlueBits = pfd.cAccumBlueBits;
u->accumAlphaBits = pfd.cAccumAlphaBits;
u->auxBuffers = pfd.cAuxBuffers;
if (pfd.dwFlags & PFD_STEREO)
u->stereo = GL_TRUE;
if (pfd.dwFlags & PFD_DOUBLEBUFFER)
u->doublebuffer = GL_TRUE;
}
u->wgl = n;
usableCount++;
}
if (!usableCount)
{
_glfwInputError(GLFW_API_UNAVAILABLE,
"WGL: The driver does not appear to support OpenGL");
free(usableConfigs);
return GL_FALSE;
}
closest = _glfwChooseFBConfig(desired, usableConfigs, usableCount);
if (!closest)
{
_glfwInputError(GLFW_PLATFORM_ERROR,
"WGL: Failed to find a suitable pixel format");
free(usableConfigs);
return GL_FALSE;
}
*result = closest->wgl;
free(usableConfigs);
return GL_TRUE;
}
//////////////////////////////////////////////////////////////////////////
////// GLFW internal API //////
//////////////////////////////////////////////////////////////////////////
// Initialize WGL
//
int _glfwInitContextAPI(void)
{
if (!_glfwInitTLS())
return GL_FALSE;
_glfw.wgl.opengl32.instance = LoadLibraryW(L"opengl32.dll");
if (!_glfw.wgl.opengl32.instance)
{
_glfwInputError(GLFW_PLATFORM_ERROR, "Failed to load opengl32.dll");
return GL_FALSE;
}
return GL_TRUE;
}
// Terminate WGL
//
void _glfwTerminateContextAPI(void)
{
if (_glfw.wgl.opengl32.instance)
FreeLibrary(_glfw.wgl.opengl32.instance);
_glfwTerminateTLS();
}
#define setWGLattrib(attribName, attribValue) \
{ \
attribs[index++] = attribName; \
attribs[index++] = attribValue; \
assert((size_t) index < sizeof(attribs) / sizeof(attribs[0])); \
}
// Create the OpenGL or OpenGL ES context
//
int _glfwCreateContext(_GLFWwindow* window,
const _GLFWctxconfig* ctxconfig,
const _GLFWfbconfig* fbconfig)
{
int attribs[40];
int pixelFormat = 0;
PIXELFORMATDESCRIPTOR pfd;
HGLRC share = NULL;
if (ctxconfig->share)
share = ctxconfig->share->wgl.context;
window->wgl.dc = GetDC(window->win32.handle);
if (!window->wgl.dc)
{
_glfwInputError(GLFW_PLATFORM_ERROR,
"Win32: Failed to retrieve DC for window");
return GL_FALSE;
}
if (!choosePixelFormat(window, fbconfig, &pixelFormat))
return GL_FALSE;
if (!DescribePixelFormat(window->wgl.dc, pixelFormat, sizeof(pfd), &pfd))
{
_glfwInputError(GLFW_PLATFORM_ERROR,
"Win32: Failed to retrieve PFD for selected pixel "
"format");
return GL_FALSE;
}
if (!SetPixelFormat(window->wgl.dc, pixelFormat, &pfd))
{
_glfwInputError(GLFW_PLATFORM_ERROR,
"Win32: Failed to set selected pixel format");
return GL_FALSE;
}
if (window->wgl.ARB_create_context)
{
int index = 0, mask = 0, flags = 0, strategy = 0;
if (ctxconfig->api == GLFW_OPENGL_API)
{
if (ctxconfig->forward)
flags |= WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB;
if (ctxconfig->debug)
flags |= WGL_CONTEXT_DEBUG_BIT_ARB;
if (ctxconfig->profile)
{
if (ctxconfig->profile == GLFW_OPENGL_CORE_PROFILE)
mask |= WGL_CONTEXT_CORE_PROFILE_BIT_ARB;
else if (ctxconfig->profile == GLFW_OPENGL_COMPAT_PROFILE)
mask |= WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB;
}
}
else
mask |= WGL_CONTEXT_ES2_PROFILE_BIT_EXT;
if (ctxconfig->robustness)
{
if (window->wgl.ARB_create_context_robustness)
{
if (ctxconfig->robustness == GLFW_NO_RESET_NOTIFICATION)
strategy = WGL_NO_RESET_NOTIFICATION_ARB;
else if (ctxconfig->robustness == GLFW_LOSE_CONTEXT_ON_RESET)
strategy = WGL_LOSE_CONTEXT_ON_RESET_ARB;
flags |= WGL_CONTEXT_ROBUST_ACCESS_BIT_ARB;
}
}
if (ctxconfig->release)
{
if (window->wgl.ARB_context_flush_control)
{
if (ctxconfig->release == GLFW_RELEASE_BEHAVIOR_NONE)
{
setWGLattrib(WGL_CONTEXT_RELEASE_BEHAVIOR_ARB,
WGL_CONTEXT_RELEASE_BEHAVIOR_NONE_ARB);
}
else if (ctxconfig->release == GLFW_RELEASE_BEHAVIOR_FLUSH)
{
setWGLattrib(WGL_CONTEXT_RELEASE_BEHAVIOR_ARB,
WGL_CONTEXT_RELEASE_BEHAVIOR_FLUSH_ARB);
}
}
}
if (ctxconfig->major != 1 || ctxconfig->minor != 0)
{
// NOTE: Only request an explicitly versioned context when
// necessary, as explicitly requesting version 1.0 does not
// always return the highest available version
setWGLattrib(WGL_CONTEXT_MAJOR_VERSION_ARB, ctxconfig->major);
setWGLattrib(WGL_CONTEXT_MINOR_VERSION_ARB, ctxconfig->minor);
}
if (flags)
setWGLattrib(WGL_CONTEXT_FLAGS_ARB, flags);
if (mask)
setWGLattrib(WGL_CONTEXT_PROFILE_MASK_ARB, mask);
if (strategy)
setWGLattrib(WGL_CONTEXT_RESET_NOTIFICATION_STRATEGY_ARB, strategy);
setWGLattrib(0, 0);
window->wgl.context = window->wgl.CreateContextAttribsARB(window->wgl.dc,
share,
attribs);
if (!window->wgl.context)
{
_glfwInputError(GLFW_VERSION_UNAVAILABLE,
"WGL: Failed to create OpenGL context");
return GL_FALSE;
}
}
else
{
window->wgl.context = wglCreateContext(window->wgl.dc);
if (!window->wgl.context)
{
_glfwInputError(GLFW_PLATFORM_ERROR,
"WGL: Failed to create OpenGL context");
return GL_FALSE;
}
if (share)
{
if (!wglShareLists(share, window->wgl.context))
{
_glfwInputError(GLFW_PLATFORM_ERROR,
"WGL: Failed to enable sharing with specified "
"OpenGL context");
return GL_FALSE;
}
}
}
_glfwPlatformMakeContextCurrent(window);
initWGLExtensions(window);
return GL_TRUE;
}
#undef setWGLattrib
// Destroy the OpenGL context
//
void _glfwDestroyContext(_GLFWwindow* window)
{
if (window->wgl.context)
{
wglDeleteContext(window->wgl.context);
window->wgl.context = NULL;
}
if (window->wgl.dc)
{
ReleaseDC(window->win32.handle, window->wgl.dc);
window->wgl.dc = NULL;
}
}
// Analyzes the specified context for possible recreation
//
int _glfwAnalyzeContext(const _GLFWwindow* window,
const _GLFWctxconfig* ctxconfig,
const _GLFWfbconfig* fbconfig)
{
GLboolean required = GL_FALSE;
if (ctxconfig->api == GLFW_OPENGL_API)
{
if (ctxconfig->forward)
{
if (!window->wgl.ARB_create_context)
{
_glfwInputError(GLFW_VERSION_UNAVAILABLE,
"WGL: A forward compatible OpenGL context "
"requested but WGL_ARB_create_context is "
"unavailable");
return _GLFW_RECREATION_IMPOSSIBLE;
}
required = GL_TRUE;
}
if (ctxconfig->profile)
{
if (!window->wgl.ARB_create_context_profile)
{
_glfwInputError(GLFW_VERSION_UNAVAILABLE,
"WGL: OpenGL profile requested but "
"WGL_ARB_create_context_profile is unavailable");
return _GLFW_RECREATION_IMPOSSIBLE;
}
required = GL_TRUE;
}
if (ctxconfig->release)
{
if (window->wgl.ARB_context_flush_control)
required = GL_TRUE;
}
}
else
{
if (!window->wgl.ARB_create_context ||
!window->wgl.ARB_create_context_profile ||
!window->wgl.EXT_create_context_es2_profile)
{
_glfwInputError(GLFW_API_UNAVAILABLE,
"WGL: OpenGL ES requested but "
"WGL_ARB_create_context_es2_profile is unavailable");
return _GLFW_RECREATION_IMPOSSIBLE;
}
required = GL_TRUE;
}
if (ctxconfig->major != 1 || ctxconfig->minor != 0)
{
if (window->wgl.ARB_create_context)
required = GL_TRUE;
}
if (ctxconfig->debug)
{
if (window->wgl.ARB_create_context)
required = GL_TRUE;
}
if (fbconfig->samples > 0)
{
// We want FSAA, but can we get it?
// FSAA is not a hard constraint, so otherwise we just don't care
if (window->wgl.ARB_multisample && window->wgl.ARB_pixel_format)
{
// We appear to have both the extension and the means to ask for it
required = GL_TRUE;
}
}
if (fbconfig->sRGB)
{
// We want sRGB, but can we get it?
// sRGB is not a hard constraint, so otherwise we just don't care
if (window->wgl.ARB_framebuffer_sRGB && window->wgl.ARB_pixel_format)
{
// We appear to have both the extension and the means to ask for it
required = GL_TRUE;
}
}
if (required)
return _GLFW_RECREATION_REQUIRED;
return _GLFW_RECREATION_NOT_NEEDED;
}
//////////////////////////////////////////////////////////////////////////
////// GLFW platform API //////
//////////////////////////////////////////////////////////////////////////
void _glfwPlatformMakeContextCurrent(_GLFWwindow* window)
{
if (window)
wglMakeCurrent(window->wgl.dc, window->wgl.context);
else
wglMakeCurrent(NULL, NULL);
_glfwSetCurrentContext(window);
}
void _glfwPlatformSwapBuffers(_GLFWwindow* window)
{
SwapBuffers(window->wgl.dc);
}
void _glfwPlatformSwapInterval(int interval)
{
_GLFWwindow* window = _glfwPlatformGetCurrentContext();
#if !defined(_GLFW_USE_DWM_SWAP_INTERVAL)
if (_glfwIsCompositionEnabled() && interval)
{
// Don't enabled vsync when desktop compositing is enabled, as it leads
// to frame jitter
return;
}
#endif
if (window->wgl.EXT_swap_control)
window->wgl.SwapIntervalEXT(interval);
}
int _glfwPlatformExtensionSupported(const char* extension)
{
const GLubyte* extensions;
_GLFWwindow* window = _glfwPlatformGetCurrentContext();
if (window->wgl.GetExtensionsStringEXT != NULL)
{
extensions = (GLubyte*) window->wgl.GetExtensionsStringEXT();
if (extensions != NULL)
{
if (_glfwStringInExtensionString(extension, extensions))
return GL_TRUE;
}
}
if (window->wgl.GetExtensionsStringARB != NULL)
{
extensions = (GLubyte*) window->wgl.GetExtensionsStringARB(window->wgl.dc);
if (extensions != NULL)
{
if (_glfwStringInExtensionString(extension, extensions))
return GL_TRUE;
}
}
return GL_FALSE;
}
GLFWglproc _glfwPlatformGetProcAddress(const char* procname)
{
const GLFWglproc proc = (GLFWglproc) wglGetProcAddress(procname);
if (proc)
return proc;
return (GLFWglproc) GetProcAddress(_glfw.wgl.opengl32.instance, procname);
}
//////////////////////////////////////////////////////////////////////////
////// GLFW native API //////
//////////////////////////////////////////////////////////////////////////
GLFWAPI HGLRC glfwGetWGLContext(GLFWwindow* handle)
{
_GLFWwindow* window = (_GLFWwindow*) handle;
_GLFW_REQUIRE_INIT_OR_RETURN(NULL);
return window->wgl.context;
}