1 files changed, 41 insertions, 35 deletions

diff --git a/src/plugins/platforms/windows/qwindowsglcontext.cpp b/src/plugins/platforms/windows/qwindowsglcontext.cpp
index 101db75d0b..d9521e7e08 100644
--- a/src/plugins/platforms/windows/qwindowsglcontext.cpp
+++ b/src/plugins/platforms/windows/qwindowsglcontext.cpp
@@ -196,6 +196,7 @@ bool QWindowsOpengl32DLL::init(bool softwareRendering)
     wglShareLists = reinterpret_cast<BOOL (WINAPI *)(HGLRC, HGLRC)>(resolve("wglShareLists"));
     wglSwapBuffers = reinterpret_cast<BOOL (WINAPI *)(HDC)>(resolve("wglSwapBuffers"));
     wglSetPixelFormat = reinterpret_cast<BOOL (WINAPI *)(HDC, int, const PIXELFORMATDESCRIPTOR *)>(resolve("wglSetPixelFormat"));
+    wglDescribePixelFormat = reinterpret_cast<int (WINAPI *)(HDC, int, UINT, PIXELFORMATDESCRIPTOR *)>(resolve("wglDescribePixelFormat"));
 
     glGetError = reinterpret_cast<GLenum (APIENTRY *)()>(resolve("glGetError"));
     glGetIntegerv = reinterpret_cast<void (APIENTRY *)(GLenum , GLint *)>(resolve("glGetIntegerv"));
@@ -214,6 +215,11 @@ BOOL QWindowsOpengl32DLL::setPixelFormat(HDC dc, int pf, const PIXELFORMATDESCRI
     return moduleIsNotOpengl32() ? wglSetPixelFormat(dc, pf, pfd) : SetPixelFormat(dc, pf, pfd);
 }
 
+int QWindowsOpengl32DLL::describePixelFormat(HDC dc, int pf, UINT size, PIXELFORMATDESCRIPTOR *pfd)
+{
+    return moduleIsNotOpengl32() ? wglDescribePixelFormat(dc, pf, size, pfd) : DescribePixelFormat(dc, pf, size, pfd);
+}
+
 QWindowsOpenGLContext *QOpenGLStaticContext::createContext(QOpenGLContext *context)
 {
     return new QWindowsGLContext(this, context);
@@ -322,11 +328,11 @@ static inline bool
 
 static void describeFormats(HDC hdc)
 {
-    const int pfiMax = DescribePixelFormat(hdc, 0, 0, nullptr);
-    for (int i = 0; i < pfiMax; i++) {
+    const int pfiMax = QOpenGLStaticContext::opengl32.describePixelFormat(hdc, 0, 0, nullptr);
+    for (int i = 1; i <= pfiMax; i++) {
         PIXELFORMATDESCRIPTOR pfd;
         initPixelFormatDescriptor(&pfd);
-        DescribePixelFormat(hdc, i, sizeof(PIXELFORMATDESCRIPTOR), &pfd);
+        QOpenGLStaticContext::opengl32.describePixelFormat(hdc, i, sizeof(PIXELFORMATDESCRIPTOR), &pfd);
         qCDebug(lcQpaGl) << '#' << i << '/' << pfiMax << ':' << pfd;
     }
 }
@@ -617,7 +623,7 @@ static int choosePixelFormat(HDC hdc,
     // Verify if format is acceptable. Note that the returned
     // formats have been observed to not contain PFD_SUPPORT_OPENGL, ignore.
     initPixelFormatDescriptor(obtainedPfd);
-    DescribePixelFormat(hdc, pixelFormat, sizeof(PIXELFORMATDESCRIPTOR), obtainedPfd);
+    QOpenGLStaticContext::opengl32.describePixelFormat(hdc, pixelFormat, sizeof(PIXELFORMATDESCRIPTOR), obtainedPfd);
     if (!isAcceptableFormat(additional, *obtainedPfd, true)) {
         qCDebug(lcQpaGl) << __FUNCTION__ << " obtained px #" << pixelFormat
             << " not acceptable=" << *obtainedPfd;
@@ -885,13 +891,6 @@ QWindowsOpenGLContextFormat QWindowsOpenGLContextFormat::current()
         result.profile = QSurfaceFormat::CoreProfile;
     else if (value & GL_CONTEXT_COMPATIBILITY_PROFILE_BIT)
         result.profile = QSurfaceFormat::CompatibilityProfile;
-    if (result.version < 0x0400)
-        return result;
-    // v4.0 onwards
-    value = 0;
-    QOpenGLStaticContext::opengl32.glGetIntegerv(RESET_NOTIFICATION_STRATEGY_ARB, &value);
-    if (value == LOSE_CONTEXT_ON_RESET_ARB)
-        result.options |= QSurfaceFormat::ResetNotification;
     return result;
 }
 
@@ -969,6 +968,7 @@ QOpenGLTemporaryContext::~QOpenGLTemporaryContext()
 */
 
 #define SAMPLE_BUFFER_EXTENSION "GL_ARB_multisample"
+#define ROBUSTNESS_EXTENSION "GL_ARB_robustness"
 
 QOpenGLStaticContext::QOpenGLStaticContext() :
     vendor(QOpenGLStaticContext::getGlString(GL_VENDOR)),
@@ -989,9 +989,31 @@ QOpenGLStaticContext::QOpenGLStaticContext() :
     wglGetExtensionsStringARB(reinterpret_cast<WglGetExtensionsStringARB>(
         reinterpret_cast<QFunctionPointer>(QOpenGLStaticContext::opengl32.wglGetProcAddress("wglGetExtensionsStringARB"))))
 {
-    if (extensionNames.startsWith(SAMPLE_BUFFER_EXTENSION " ")
-            || extensionNames.indexOf(" " SAMPLE_BUFFER_EXTENSION " ") != -1)
-        extensions |= SampleBuffers;
+    if (defaultFormat.version < 0x0300) {
+        if (extensionNames.startsWith(SAMPLE_BUFFER_EXTENSION " ")
+                || extensionNames.indexOf(" " SAMPLE_BUFFER_EXTENSION " ") != -1)
+            extensions |= SampleBuffers;
+        if (extensionNames.startsWith(ROBUSTNESS_EXTENSION " ")
+                || extensionNames.indexOf(" " ROBUSTNESS_EXTENSION " ") != -1)
+            extensions |= Robustness;
+    } else {
+        typedef const GLubyte * (APIENTRY *glGetStringi_t)(GLenum, GLuint);
+        auto glGetStringi = reinterpret_cast<glGetStringi_t>(
+            reinterpret_cast<QFunctionPointer>(QOpenGLStaticContext::opengl32.wglGetProcAddress("glGetStringi")));
+        if (glGetStringi) {
+            GLint n = 0;
+            QOpenGLStaticContext::opengl32.glGetIntegerv(GL_NUM_EXTENSIONS, &n);
+            for (GLint i = 0; i < n; ++i) {
+                const char *p = reinterpret_cast<const char *>(glGetStringi(GL_EXTENSIONS, i));
+                if (p) {
+                    if (!strcmp(p, SAMPLE_BUFFER_EXTENSION))
+                        extensions |= SampleBuffers;
+                    else if (!strcmp(p, ROBUSTNESS_EXTENSION))
+                        extensions |= Robustness;
+                }
+            }
+        }
+    }
 }
 
 QByteArray QOpenGLStaticContext::getGlString(unsigned int which)
@@ -1230,27 +1252,11 @@ bool QWindowsGLContext::updateObtainedParams(HDC hdc, int *obtainedSwapInterval)
     if (m_staticContext->wglGetSwapInternalExt && obtainedSwapInterval)
         *obtainedSwapInterval = m_staticContext->wglGetSwapInternalExt();
 
-    bool hasRobustness = false;
-    if (m_obtainedFormat.majorVersion() < 3) {
-        const char *exts = reinterpret_cast<const char *>(QOpenGLStaticContext::opengl32.glGetString(GL_EXTENSIONS));
-        hasRobustness = exts && strstr(exts, "GL_ARB_robustness");
-    } else {
-        typedef const GLubyte * (APIENTRY *glGetStringi_t)(GLenum, GLuint);
-        auto glGetStringi = reinterpret_cast<glGetStringi_t>(
-            reinterpret_cast<QFunctionPointer>(QOpenGLStaticContext::opengl32.wglGetProcAddress("glGetStringi")));
-        if (glGetStringi) {
-            GLint n = 0;
-            QOpenGLStaticContext::opengl32.glGetIntegerv(GL_NUM_EXTENSIONS, &n);
-            for (GLint i = 0; i < n; ++i) {
-                const char *p = reinterpret_cast<const char *>(glGetStringi(GL_EXTENSIONS, i));
-                if (p && !strcmp(p, "GL_ARB_robustness")) {
-                    hasRobustness = true;
-                    break;
-                }
-            }
-        }
-    }
-    if (hasRobustness) {
+    if (testFlag(m_staticContext->extensions, QOpenGLStaticContext::Robustness)) {
+        GLint value = 0;
+        QOpenGLStaticContext::opengl32.glGetIntegerv(RESET_NOTIFICATION_STRATEGY_ARB, &value);
+        if (value == LOSE_CONTEXT_ON_RESET_ARB)
+            m_obtainedFormat.setOption(QSurfaceFormat::ResetNotification);
         m_getGraphicsResetStatus = reinterpret_cast<GlGetGraphicsResetStatusArbType>(
             reinterpret_cast<QFunctionPointer>(QOpenGLStaticContext::opengl32.wglGetProcAddress("glGetGraphicsResetStatusARB")));
     }