Basic Vulkan enablers

For Android, Windows and xcb. Verified on Win10 with NVIDIA, Win10
with AMD, Android with Tegra K1, Android aarch64 with Tegra X1, and
Linux aarch64 with Tegra X1 (Jetson TX1, L4T).

Introduce QPA-based Vulkan library loader, core function resolver, and
instance creation support. In addition to creating a new VkInstance,
adopting an existing one from an external engine is supported as well.

The WSI specifics are hidden in the platform plugins. Vulkan-capable
windows use the new surface type VulkanSurface and are associated with
a QVulkanInstance.

On Windows VULKAN_SDK is picked up automatically so finding vulkan.h
needs no additional manual steps once the LunarG SDK is installed.

[ChangeLog][QtGui] Added support for rendering to QWindow via the Vulkan
graphics API.

Task-number: QTBUG-55981
Change-Id: I50fa92d313fa440e0cc73939c6d7510ca317fbc9
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

9 files changed, 438 insertions, 5 deletions

diff --git a/src/plugins/platforms/xcb/qxcbintegration.cpp b/src/plugins/platforms/xcb/qxcbintegration.cpp
index 40858b39e0..7f1cff1299 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.cpp
+++ b/src/plugins/platforms/xcb/qxcbintegration.cpp
@@ -83,6 +83,11 @@
 
 #include <QtCore/QFileInfo>
 
+#if QT_CONFIG(vulkan)
+#include "qxcbvulkaninstance.h"
+#include "qxcbvulkanwindow.h"
+#endif
+
 QT_BEGIN_NAMESPACE
 
 // Find out if our parent process is gdb by looking at the 'exe' symlink under /proc,.
@@ -199,11 +204,19 @@ QPlatformWindow *QXcbIntegration::createPlatformWindow(QWindow *window) const
 {
     QXcbScreen *screen = static_cast<QXcbScreen *>(window->screen()->handle());
     QXcbGlIntegration *glIntegration = screen->connection()->glIntegration();
-    if (window->type() != Qt::Desktop && window->supportsOpenGL()) {
-        if (glIntegration) {
-            QXcbWindow *xcbWindow = glIntegration->createWindow(window);
+    if (window->type() != Qt::Desktop) {
+        if (window->supportsOpenGL()) {
+            if (glIntegration) {
+                QXcbWindow *xcbWindow = glIntegration->createWindow(window);
+                xcbWindow->create();
+                return xcbWindow;
+            }
+#if QT_CONFIG(vulkan)
+        } else if (window->surfaceType() == QSurface::VulkanSurface) {
+            QXcbWindow *xcbWindow = new QXcbVulkanWindow(window);
             xcbWindow->create();
             return xcbWindow;
+#endif
         }
     }
 
@@ -498,4 +511,11 @@ void QXcbIntegration::beep() const
     xcb_bell(connection, 0);
 }
 
+#if QT_CONFIG(vulkan)
+QPlatformVulkanInstance *QXcbIntegration::createPlatformVulkanInstance(QVulkanInstance *instance) const
+{
+    return new QXcbVulkanInstance(instance);
+}
+#endif
+
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/xcb/qxcbintegration.h b/src/plugins/platforms/xcb/qxcbintegration.h
index baa5c9d835..6e12739138 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.h
+++ b/src/plugins/platforms/xcb/qxcbintegration.h
@@ -113,6 +113,10 @@ public:
 
     void beep() const override;
 
+#if QT_CONFIG(vulkan)
+    QPlatformVulkanInstance *createPlatformVulkanInstance(QVulkanInstance *instance) const override;
+#endif
+
     static QXcbIntegration *instance() { return m_instance; }
 
 private:
diff --git a/src/plugins/platforms/xcb/qxcbnativeinterface.cpp b/src/plugins/platforms/xcb/qxcbnativeinterface.cpp
index cc05671580..eff38fc868 100644
--- a/src/plugins/platforms/xcb/qxcbnativeinterface.cpp
+++ b/src/plugins/platforms/xcb/qxcbnativeinterface.cpp
@@ -67,6 +67,10 @@
 
 #include "qxcbnativeinterfacehandler.h"
 
+#if QT_CONFIG(vulkan)
+#include "qxcbvulkanwindow.h"
+#endif
+
 QT_BEGIN_NAMESPACE
 
 // return QXcbNativeInterface::ResourceType for the key.
@@ -82,7 +86,8 @@ static int resourceType(const QByteArray &key)
         QByteArrayLiteral("rootwindow"),
         QByteArrayLiteral("subpixeltype"), QByteArrayLiteral("antialiasingenabled"),
         QByteArrayLiteral("atspibus"),
-        QByteArrayLiteral("compositingenabled")
+        QByteArrayLiteral("compositingenabled"),
+        QByteArrayLiteral("vksurface")
     };
     const QByteArray *end = names + sizeof(names) / sizeof(names[0]);
     const QByteArray *result = std::find(names, end, key);
@@ -257,6 +262,14 @@ void *QXcbNativeInterface::nativeResourceForWindow(const QByteArray &resourceStr
     case Screen:
         result = screenForWindow(window);
         break;
+#if QT_CONFIG(vulkan)
+    case VkSurface:
+        if (window->surfaceType() == QSurface::VulkanSurface && window->handle()) {
+            // return a pointer to the VkSurfaceKHR value, not the value itself
+            result = static_cast<QXcbVulkanWindow *>(window->handle())->surface();
+        }
+        break;
+#endif
     default:
         break;
     }
diff --git a/src/plugins/platforms/xcb/qxcbnativeinterface.h b/src/plugins/platforms/xcb/qxcbnativeinterface.h
index 4186d77f4d..b9f1ebcdc6 100644
--- a/src/plugins/platforms/xcb/qxcbnativeinterface.h
+++ b/src/plugins/platforms/xcb/qxcbnativeinterface.h
@@ -73,7 +73,8 @@ public:
         ScreenSubpixelType,
         ScreenAntialiasingEnabled,
         AtspiBus,
-        CompositingEnabled
+        CompositingEnabled,
+        VkSurface
     };
 
     QXcbNativeInterface();
diff --git a/src/plugins/platforms/xcb/qxcbvulkaninstance.cpp b/src/plugins/platforms/xcb/qxcbvulkaninstance.cpp
new file mode 100644
index 0000000000..4d540defa9
--- /dev/null
+++ b/src/plugins/platforms/xcb/qxcbvulkaninstance.cpp
@@ -0,0 +1,156 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qxcbvulkaninstance.h"
+#include "qxcbwindow.h"
+#include "qxcbscreen.h"
+
+QT_BEGIN_NAMESPACE
+
+QXcbVulkanInstance::QXcbVulkanInstance(QVulkanInstance *instance)
+    : m_instance(instance),
+      m_getPhysDevPresSupport(nullptr),
+      m_createSurface(nullptr),
+      m_destroySurface(nullptr)
+{
+    if (qEnvironmentVariableIsSet("QT_VULKAN_LIB"))
+        m_lib.setFileName(QString::fromUtf8(qgetenv("QT_VULKAN_LIB")));
+    else
+        m_lib.setFileName(QStringLiteral("vulkan"));
+
+    if (!m_lib.load()) {
+        qWarning("Failed to load %s: %s", qPrintable(m_lib.fileName()), qPrintable(m_lib.errorString()));
+        return;
+    }
+
+    init(&m_lib);
+}
+
+QXcbVulkanInstance::~QXcbVulkanInstance()
+{
+}
+
+void QXcbVulkanInstance::createOrAdoptInstance()
+{
+    initInstance(m_instance, QByteArrayList() << QByteArrayLiteral("VK_KHR_xcb_surface"));
+
+    if (!m_vkInst)
+        return;
+
+    m_getPhysDevPresSupport = reinterpret_cast<PFN_vkGetPhysicalDeviceXcbPresentationSupportKHR>(
+                m_vkGetInstanceProcAddr(m_vkInst, "vkGetPhysicalDeviceXcbPresentationSupportKHR"));
+    if (!m_getPhysDevPresSupport)
+        qWarning("Failed to find vkGetPhysicalDeviceXcbPresentationSupportKHR");
+}
+
+bool QXcbVulkanInstance::supportsPresent(VkPhysicalDevice physicalDevice,
+                                         uint32_t queueFamilyIndex,
+                                         QWindow *window)
+{
+    if (!m_getPhysDevPresSupport || !m_getPhysDevSurfaceSupport)
+        return true;
+
+    QXcbWindow *w = static_cast<QXcbWindow *>(window->handle());
+    if (!w) {
+        qWarning("Attempted to call supportsPresent() without a valid platform window");
+        return false;
+    }
+    xcb_connection_t *connection = w->xcbScreen()->xcb_connection();
+    bool ok = m_getPhysDevPresSupport(physicalDevice, queueFamilyIndex, connection, w->visualId());
+
+    VkSurfaceKHR surface = QVulkanInstance::surfaceForWindow(window);
+    VkBool32 supported = false;
+    m_getPhysDevSurfaceSupport(physicalDevice, queueFamilyIndex, surface, &supported);
+    ok &= bool(supported);
+
+    return ok;
+}
+
+VkSurfaceKHR QXcbVulkanInstance::createSurface(QXcbWindow *window)
+{
+    VkSurfaceKHR surface = 0;
+
+    if (!m_createSurface) {
+        m_createSurface = reinterpret_cast<PFN_vkCreateXcbSurfaceKHR>(
+                    m_vkGetInstanceProcAddr(m_vkInst, "vkCreateXcbSurfaceKHR"));
+    }
+    if (!m_createSurface) {
+        qWarning("Failed to find vkCreateXcbSurfaceKHR");
+        return surface;
+    }
+    if (!m_destroySurface) {
+        m_destroySurface = reinterpret_cast<PFN_vkDestroySurfaceKHR>(
+                    m_vkGetInstanceProcAddr(m_vkInst, "vkDestroySurfaceKHR"));
+    }
+    if (!m_destroySurface) {
+        qWarning("Failed to find vkDestroySurfaceKHR");
+        return surface;
+    }
+
+    VkXcbSurfaceCreateInfoKHR surfaceInfo;
+    memset(&surfaceInfo, 0, sizeof(surfaceInfo));
+    surfaceInfo.sType = VK_STRUCTURE_TYPE_XCB_SURFACE_CREATE_INFO_KHR;
+    surfaceInfo.connection = window->xcbScreen()->xcb_connection();
+    surfaceInfo.window = window->xcb_window();
+    VkResult err = m_createSurface(m_vkInst, &surfaceInfo, nullptr, &surface);
+    if (err != VK_SUCCESS)
+        qWarning("Failed to create Vulkan surface: %d", err);
+
+    return surface;
+}
+
+void QXcbVulkanInstance::destroySurface(VkSurfaceKHR surface)
+{
+    if (m_destroySurface && surface)
+        m_destroySurface(m_vkInst, surface, nullptr);
+}
+
+void QXcbVulkanInstance::presentQueued(QWindow *window)
+{
+    QXcbWindow *w = static_cast<QXcbWindow *>(window->handle());
+    if (!w) {
+        qWarning("Attempted to call presentQueued() without a valid platform window");
+        return;
+    }
+
+    if (w->needsSync())
+        w->postSyncWindowRequest();
+}
+
+QT_END_NAMESPACE
diff --git a/src/plugins/platforms/xcb/qxcbvulkaninstance.h b/src/plugins/platforms/xcb/qxcbvulkaninstance.h
new file mode 100644
index 0000000000..dbe057d944
--- /dev/null
+++ b/src/plugins/platforms/xcb/qxcbvulkaninstance.h
@@ -0,0 +1,79 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QXCBVULKANINSTANCE_H
+#define QXCBVULKANINSTANCE_H
+
+#if defined(VULKAN_H_) && !defined(VK_USE_PLATFORM_XCB_KHR)
+#error "vulkan.h included without xcb WSI"
+#endif
+
+#define VK_USE_PLATFORM_XCB_KHR
+
+#include <QtVulkanSupport/private/qbasicvulkanplatforminstance_p.h>
+#include <QLibrary>
+
+QT_BEGIN_NAMESPACE
+
+class QXcbWindow;
+
+class QXcbVulkanInstance : public QBasicPlatformVulkanInstance
+{
+public:
+    QXcbVulkanInstance(QVulkanInstance *instance);
+    ~QXcbVulkanInstance();
+
+    void createOrAdoptInstance() override;
+    bool supportsPresent(VkPhysicalDevice physicalDevice, uint32_t queueFamilyIndex, QWindow *window) override;
+    void presentQueued(QWindow *window) override;
+
+    VkSurfaceKHR createSurface(QXcbWindow *window);
+    void destroySurface(VkSurfaceKHR surface);
+
+private:
+    QVulkanInstance *m_instance;
+    QLibrary m_lib;
+    PFN_vkGetPhysicalDeviceXcbPresentationSupportKHR m_getPhysDevPresSupport;
+    PFN_vkCreateXcbSurfaceKHR m_createSurface;
+    PFN_vkDestroySurfaceKHR m_destroySurface;
+};
+
+QT_END_NAMESPACE
+
+#endif // QXCBVULKANINSTANCE_H
diff --git a/src/plugins/platforms/xcb/qxcbvulkanwindow.cpp b/src/plugins/platforms/xcb/qxcbvulkanwindow.cpp
new file mode 100644
index 0000000000..f9136c8b72
--- /dev/null
+++ b/src/plugins/platforms/xcb/qxcbvulkanwindow.cpp
@@ -0,0 +1,83 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qxcbvulkanwindow.h"
+
+QT_BEGIN_NAMESPACE
+
+QXcbVulkanWindow::QXcbVulkanWindow(QWindow *window)
+    : QXcbWindow(window),
+      m_surface(0)
+{
+}
+
+QXcbVulkanWindow::~QXcbVulkanWindow()
+{
+    if (m_surface) {
+        QVulkanInstance *inst = window()->vulkanInstance();
+        if (inst)
+            static_cast<QXcbVulkanInstance *>(inst->handle())->destroySurface(m_surface);
+    }
+}
+
+void QXcbVulkanWindow::resolveFormat(const QSurfaceFormat &format)
+{
+    m_format = format;
+    m_format.setRedBufferSize(8);
+    m_format.setGreenBufferSize(8);
+    m_format.setBlueBufferSize(8);
+}
+
+VkSurfaceKHR *QXcbVulkanWindow::surface()
+{
+    if (m_surface)
+        return &m_surface;
+
+    QVulkanInstance *inst = window()->vulkanInstance();
+    if (!inst) {
+        qWarning("Attempted to create Vulkan surface without an instance; was QWindow::setVulkanInstance() called?");
+        return nullptr;
+    }
+    QXcbVulkanInstance *xcbinst = static_cast<QXcbVulkanInstance *>(inst->handle());
+    m_surface = xcbinst->createSurface(this);
+
+    return &m_surface;
+}
+
+QT_END_NAMESPACE
diff --git a/src/plugins/platforms/xcb/qxcbvulkanwindow.h b/src/plugins/platforms/xcb/qxcbvulkanwindow.h
new file mode 100644
index 0000000000..43c96820c5
--- /dev/null
+++ b/src/plugins/platforms/xcb/qxcbvulkanwindow.h
@@ -0,0 +1,65 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QXCBVULKANWINDOW_H
+#define QXCBVULKANWINDOW_H
+
+#include "qxcbwindow.h"
+#include "qxcbvulkaninstance.h"
+
+QT_BEGIN_NAMESPACE
+
+class QXcbVulkanWindow : public QXcbWindow
+{
+public:
+    QXcbVulkanWindow(QWindow *window);
+    ~QXcbVulkanWindow();
+
+    VkSurfaceKHR *surface();
+
+protected:
+    void resolveFormat(const QSurfaceFormat &format) override;
+
+private:
+    VkSurfaceKHR m_surface;
+};
+
+QT_END_NAMESPACE
+
+#endif // QXCBVULKANWINDOW_H
diff --git a/src/plugins/platforms/xcb/xcb_qpa_lib.pro b/src/plugins/platforms/xcb/xcb_qpa_lib.pro
index 6db0c76dea..c7f2993220 100644
--- a/src/plugins/platforms/xcb/xcb_qpa_lib.pro
+++ b/src/plugins/platforms/xcb/xcb_qpa_lib.pro
@@ -10,6 +10,8 @@ QT += \
 qtHaveModule(linuxaccessibility_support-private): \
     QT += linuxaccessibility_support-private
 
+qtConfig(vulkan): QT += vulkan_support-private
+
 SOURCES = \
         qxcbclipboard.cpp \
         qxcbconnection.cpp \
@@ -70,6 +72,16 @@ qtConfig(xcb-sm) {
 
 include(gl_integrations/gl_integrations.pri)
 
+qtConfig(vulkan) {
+    SOURCES += \
+        qxcbvulkaninstance.cpp \
+        qxcbvulkanwindow.cpp
+
+    HEADERS += \
+        qxcbvulkaninstance.h \
+        qxcbvulkanwindow.h
+}
+
 !qtConfig(system-xcb) {
     DEFINES += XCB_USE_RENDER
     QMAKE_USE += xcb-static xcb