Add matching by GL_VENDOR to QOpenGLConfig

This will be essential on Linux, especially Embedded where PCI IDs are
not that useful.

Change-Id: I2fa8ca07236e8aae203e21fe629d12aab092c7fd
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>

src/gui/opengl/qopengl.cpp

@@ -36,6 +36,7 @@
 
 #include "qopenglcontext.h"
 #include "qopenglfunctions.h"
+#include "qoffscreensurface.h"
 
 #include <QtCore/QDebug>
 #include <QtCore/QJsonDocument>
@@ -89,8 +90,8 @@ QOpenGLExtensionMatcher::QOpenGLExtensionMatcher()
 }
 
 /* Helpers to read out the list of features matching a device from
- * a Chromium driver bug list of the format using a subset of keys
- * (namely, matching by gl_vendor RegExp is not implemented):
+ * a Chromium driver bug list. Note that not all keys are supported and
+ * some may behave differently: gl_vendor is a substring match instead of regex.
  {
   "entries": [
  {
@@ -291,14 +292,14 @@ static bool matches(const QJsonObject &object,
 
     const QJsonValue vendorV = object.value(vendorIdKey());
     if (vendorV.isString()) {
-    if (gpu.vendorId != vendorV.toString().toUInt(Q_NULLPTR, /* base */ 0))
-        return false;
+        if (gpu.vendorId != vendorV.toString().toUInt(Q_NULLPTR, /* base */ 0))
+            return false;
     } else {
         if (object.contains(glVendorKey())) {
-            qWarning().nospace() << "Id " << object.value(idKey()).toInt()
-                << ": Matching by " << glVendorKey() << " is not implemented.";
-            return false;
-       }
+            const QByteArray glVendorV = object.value(glVendorKey()).toString().toUtf8();
+            if (!gpu.glVendor.contains(glVendorV))
+                return false;
+        }
     }
 
     if (gpu.deviceId) {
@@ -447,5 +448,30 @@ QSet<QString> QOpenGLConfig::gpuFeatures(const Gpu &gpu, const QString &fileName
     return gpuFeatures(gpu, OsTypeTerm::hostOs(), OsTypeTerm::hostKernelVersion(), fileName);
 }
 
+QOpenGLConfig::Gpu QOpenGLConfig::Gpu::fromContext()
+{
+    QOpenGLContext *ctx = QOpenGLContext::currentContext();
+    QScopedPointer<QOpenGLContext> tmpContext;
+    QScopedPointer<QOffscreenSurface> tmpSurface;
+    if (!ctx) {
+        tmpContext.reset(new QOpenGLContext);
+        if (!tmpContext->create()) {
+            qWarning("QOpenGLConfig::Gpu::fromContext: Failed to create temporary context");
+            return QOpenGLConfig::Gpu();
+        }
+        tmpSurface.reset(new QOffscreenSurface);
+        tmpSurface->setFormat(tmpContext->format());
+        tmpSurface->create();
+        tmpContext->makeCurrent(tmpSurface.data());
+    }
+
+    QOpenGLConfig::Gpu gpu;
+    ctx = QOpenGLContext::currentContext();
+    const GLubyte *p = ctx->functions()->glGetString(GL_VENDOR);
+    if (p)
+        gpu.glVendor = QByteArray(reinterpret_cast<const char *>(p));
+
+    return gpu;
+}
 
 QT_END_NAMESPACE

src/gui/opengl/qopengl_p.h

@@ -74,16 +74,34 @@ private:
 class Q_GUI_EXPORT QOpenGLConfig
 {
 public:
-    struct Gpu {
+    struct Q_GUI_EXPORT Gpu {
         Gpu() : vendorId(0), deviceId(0) {}
-        bool isValid() const { return deviceId; }
+        bool isValid() const { return deviceId || !glVendor.isEmpty(); }
         bool equals(const Gpu &other) const {
-            return vendorId == other.vendorId && deviceId == other.deviceId && driverVersion == other.driverVersion;
+            return vendorId == other.vendorId && deviceId == other.deviceId && driverVersion == other.driverVersion
+                && glVendor == other.glVendor;
         }
 
         uint vendorId;
         uint deviceId;
         QVersionNumber driverVersion;
+        QByteArray glVendor;
+
+        static Gpu fromDevice(uint vendorId, uint deviceId, QVersionNumber driverVersion) {
+            Gpu gpu;
+            gpu.vendorId = vendorId;
+            gpu.deviceId = deviceId;
+            gpu.driverVersion = driverVersion;
+            return gpu;
+        }
+
+        static Gpu fromGLVendor(const QByteArray &glVendor) {
+            Gpu gpu;
+            gpu.glVendor = glVendor;
+            return gpu;
+        }
+
+        static Gpu fromContext();
     };
 
     static QSet<QString> gpuFeatures(const Gpu &gpu,

src/plugins/platforms/windows/qwindowsopengltester.cpp

@@ -224,10 +224,7 @@ QWindowsOpenGLTester::Renderers QWindowsOpenGLTester::detectSupportedRenderers(c
 #elif defined(Q_OS_WINCE)
     return QWindowsOpenGLTester::Gles;
 #else
-    QOpenGLConfig::Gpu qgpu;
-    qgpu.deviceId = gpu.deviceId;
-    qgpu.vendorId = gpu.vendorId;
-    qgpu.driverVersion = gpu.driverVersion;
+    QOpenGLConfig::Gpu qgpu = QOpenGLConfig::Gpu::fromDevice(gpu.deviceId, gpu.vendorId, gpu.driverVersion);
     SupportedRenderersCache *srCache = supportedRenderersCache();
     SupportedRenderersCache::const_iterator it = srCache->find(qgpu);
     if (it != srCache->cend())

tests/auto/gui/qopenglconfig/buglist.json

@@ -101,6 +101,14 @@
             "features": [
                 "feature1"
             ]
+        },
+        {
+            "id": 128,
+            "description": "check for matching GL_VENDOR",
+            "gl_vendor": "The Qt Company",
+            "features": [
+                "cool_feature"
+            ]
         }
     ]
 }

tests/auto/gui/qopenglconfig/tst_qopenglconfig.cpp

@@ -217,6 +217,11 @@ void tst_QOpenGlConfig::testGlConfiguration()
     context.doneCurrent();
 
     qDebug().noquote() << '\n' << result;
+
+    // fromContext either uses the current context or creates a temporary dummy one.
+    QOpenGLConfig::Gpu gpu = QOpenGLConfig::Gpu::fromContext();
+    qDebug().noquote() << '\n' << "GL_VENDOR queried by QOpenGLConfig::Gpu:" << gpu.glVendor;
+    QVERIFY(!gpu.glVendor.isEmpty());
 }
 
 static inline QByteArray msgSetMismatch(const QSet<QString> &expected,
@@ -235,21 +240,28 @@ void tst_QOpenGlConfig::testBugList()
     const QString fileName = QFINDTESTDATA("buglist.json");
     QVERIFY(!fileName.isEmpty());
 
-     QSet<QString> expectedFeatures;
-     expectedFeatures << "feature1";
+    QSet<QString> expectedFeatures;
+    expectedFeatures << "feature1";
 
-    QOpenGLConfig::Gpu gpu;
-    gpu.vendorId = 0x10DE;
-    gpu.deviceId = 0x0DE9;
+    QVersionNumber driverVersion(QVector<int>() << 9 << 18 << 13 << 4460);
+    QOpenGLConfig::Gpu gpu = QOpenGLConfig::Gpu::fromDevice(0x10DE, 0x0DE9, driverVersion);
 
-#ifdef Q_COMPILER_INITIALIZER_LISTS
-    gpu.driverVersion = QVersionNumber({9, 18, 13, 4460});
-#else
-    gpu.driverVersion = QVersionNumber(QVector<int>() << 9 << 18 << 13 << 4460);
-#endif
-    const QSet<QString> actualFeatures =
-        QOpenGLConfig::gpuFeatures(gpu, QStringLiteral("win"),
-                                   QVersionNumber(6, 3), fileName);
+    QSet<QString> actualFeatures = QOpenGLConfig::gpuFeatures(gpu, QStringLiteral("win"),
+                                                              QVersionNumber(6, 3), fileName);
+    QVERIFY2(expectedFeatures == actualFeatures,
+             msgSetMismatch(expectedFeatures, actualFeatures));
+
+    gpu = QOpenGLConfig::Gpu::fromGLVendor(QByteArrayLiteral("Somebody Else"));
+    expectedFeatures.clear();
+    actualFeatures = QOpenGLConfig::gpuFeatures(gpu, QStringLiteral("linux"),
+                                                QVersionNumber(1, 0), fileName);
+    QVERIFY2(expectedFeatures == actualFeatures,
+             msgSetMismatch(expectedFeatures, actualFeatures));
+
+    gpu = QOpenGLConfig::Gpu::fromGLVendor(QByteArrayLiteral("The Qt Company"));
+    expectedFeatures = QSet<QString>() << "cool_feature";
+    actualFeatures = QOpenGLConfig::gpuFeatures(gpu, QStringLiteral("linux"),
+                                                QVersionNumber(1, 0), fileName);
     QVERIFY2(expectedFeatures == actualFeatures,
              msgSetMismatch(expectedFeatures, actualFeatures));
 }