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#include "qeglfsvulkaninstance_p.h"
#include "qeglfswindow_p.h"
#include "qeglfshooks_p.h"
#include <QLoggingCategory>

QT_BEGIN_NAMESPACE

Q_DECLARE_LOGGING_CATEGORY(qLcEglDevDebug)

QEglFSVulkanInstance::QEglFSVulkanInstance(QVulkanInstance *instance)
    : m_instance(instance)
{
    loadVulkanLibrary(QStringLiteral("vulkan"));
}

void QEglFSVulkanInstance::createOrAdoptInstance()
{
    qCDebug(qLcEglDevDebug, "Creating Vulkan instance for VK_KHR_display");

    const QByteArray extName = QByteArrayLiteral("VK_KHR_display");
    initInstance(m_instance, { extName });
    if (!m_vkInst)
        return;
    if (!enabledExtensions().contains(extName)) {
        qWarning("Failed to enable VK_KHR_display extension");
        return;
    }

#if VK_KHR_display
    m_getPhysicalDeviceDisplayPropertiesKHR = (PFN_vkGetPhysicalDeviceDisplayPropertiesKHR)
        m_vkGetInstanceProcAddr(m_vkInst, "vkGetPhysicalDeviceDisplayPropertiesKHR");
    m_getDisplayModePropertiesKHR = (PFN_vkGetDisplayModePropertiesKHR)
        m_vkGetInstanceProcAddr(m_vkInst, "vkGetDisplayModePropertiesKHR");
    m_getPhysicalDeviceDisplayPlanePropertiesKHR = (PFN_vkGetPhysicalDeviceDisplayPlanePropertiesKHR)
        m_vkGetInstanceProcAddr(m_vkInst, "vkGetPhysicalDeviceDisplayPlanePropertiesKHR");

    m_getDisplayPlaneSupportedDisplaysKHR = (PFN_vkGetDisplayPlaneSupportedDisplaysKHR)
        m_vkGetInstanceProcAddr(m_vkInst, "vkGetDisplayPlaneSupportedDisplaysKHR");
    m_getDisplayPlaneCapabilitiesKHR = (PFN_vkGetDisplayPlaneCapabilitiesKHR)
        m_vkGetInstanceProcAddr(m_vkInst, "vkGetDisplayPlaneCapabilitiesKHR");

    m_createDisplayPlaneSurfaceKHR = (PFN_vkCreateDisplayPlaneSurfaceKHR)
        m_vkGetInstanceProcAddr(m_vkInst, "vkCreateDisplayPlaneSurfaceKHR");
#endif

    m_enumeratePhysicalDevices = (PFN_vkEnumeratePhysicalDevices)
        m_vkGetInstanceProcAddr(m_vkInst, "vkEnumeratePhysicalDevices");

    // Use for first physical device, unless overridden by QT_VK_PHYSICAL_DEVICE_INDEX.
    // This behavior matches what the Vulkan backend of QRhi would do.

    uint32_t physDevCount = 0;
    m_enumeratePhysicalDevices(m_vkInst, &physDevCount, nullptr);
    if (!physDevCount) {
        qWarning("No physical devices");
        return;
    }
    QVarLengthArray<VkPhysicalDevice, 4> physDevs(physDevCount);
    VkResult err = m_enumeratePhysicalDevices(m_vkInst, &physDevCount, physDevs.data());
    if (err != VK_SUCCESS || !physDevCount) {
        qWarning("Failed to enumerate physical devices: %d", err);
        return;
    }

    if (qEnvironmentVariableIsSet("QT_VK_PHYSICAL_DEVICE_INDEX")) {
        int requestedPhysDevIndex = qEnvironmentVariableIntValue("QT_VK_PHYSICAL_DEVICE_INDEX");
        if (requestedPhysDevIndex >= 0 && uint32_t(requestedPhysDevIndex) < physDevCount)
            m_physDev = physDevs[requestedPhysDevIndex];
    }

    if (m_physDev == VK_NULL_HANDLE)
        m_physDev = physDevs[0];
}

bool QEglFSVulkanInstance::supportsPresent(VkPhysicalDevice physicalDevice,
                                           uint32_t queueFamilyIndex,
                                           QWindow *window)
{
    Q_UNUSED(physicalDevice);
    Q_UNUSED(queueFamilyIndex);
    Q_UNUSED(window);
    return true;
}

VkSurfaceKHR QEglFSVulkanInstance::createSurface(QEglFSWindow *window)
{
#if VK_KHR_display
    qCDebug(qLcEglDevDebug, "Creating VkSurfaceKHR via VK_KHR_display for window %p", (void *) window);

    if (!m_physDev) {
        qWarning("No physical device, cannot create surface");
        return VK_NULL_HANDLE;
    }

    uint32_t displayCount = 0;
    VkResult err = m_getPhysicalDeviceDisplayPropertiesKHR(m_physDev, &displayCount, nullptr);
    if (err != VK_SUCCESS) {
        qWarning("Failed to get display properties: %d", err);
        return VK_NULL_HANDLE;
    }

    qCDebug(qLcEglDevDebug, "Display count: %u", displayCount);

    QVarLengthArray<VkDisplayPropertiesKHR, 4> displayProps(displayCount);
    m_getPhysicalDeviceDisplayPropertiesKHR(m_physDev, &displayCount, displayProps.data());

    VkDisplayKHR display = VK_NULL_HANDLE;
    VkDisplayModeKHR displayMode = VK_NULL_HANDLE;
    uint32_t width = 0;
    uint32_t height = 0;

    for (uint32_t i = 0; i < displayCount; ++i) {
        const VkDisplayPropertiesKHR &disp(displayProps[i]);
        qCDebug(qLcEglDevDebug, "Display #%u:\n  display: %p\n  name: %s\n  dimensions: %ux%u\n  resolution: %ux%u",
               i, (void *) disp.display, disp.displayName,
               disp.physicalDimensions.width, disp.physicalDimensions.height,
               disp.physicalResolution.width, disp.physicalResolution.height);

        // Just pick the first display and the first mode.
        if (i == 0)
            display = disp.display;

        uint32_t modeCount = 0;
        if (m_getDisplayModePropertiesKHR(m_physDev, disp.display, &modeCount, nullptr) != VK_SUCCESS) {
            qWarning("Failed to get modes for display");
            continue;
        }
        QVarLengthArray<VkDisplayModePropertiesKHR, 16> modeProps(modeCount);
        m_getDisplayModePropertiesKHR(m_physDev, disp.display, &modeCount, modeProps.data());
        for (uint32_t j = 0; j < modeCount; ++j) {
            const VkDisplayModePropertiesKHR &mode(modeProps[j]);
            qCDebug(qLcEglDevDebug, "  Mode #%u:\n    mode: %p\n    visibleRegion: %ux%u\n    refreshRate: %u",
                   j, (void *) mode.displayMode,
                   mode.parameters.visibleRegion.width, mode.parameters.visibleRegion.height,
                   mode.parameters.refreshRate);
            if (j == 0) {
                displayMode = mode.displayMode;
                width = mode.parameters.visibleRegion.width;
                height = mode.parameters.visibleRegion.height;
            }
        }
    }

    if (display == VK_NULL_HANDLE || displayMode == VK_NULL_HANDLE) {
        qWarning("Failed to choose display and mode");
        return VK_NULL_HANDLE;
    }
    uint32_t planeCount = 0;
    err = m_getPhysicalDeviceDisplayPlanePropertiesKHR(m_physDev, &planeCount, nullptr);
    if (err != VK_SUCCESS) {
        qWarning("Failed to get plane properties: %d", err);
        return VK_NULL_HANDLE;
    }

    qCDebug(qLcEglDevDebug, "Plane count: %u", planeCount);

    QVarLengthArray<VkDisplayPlanePropertiesKHR, 4> planeProps(planeCount);
    m_getPhysicalDeviceDisplayPlanePropertiesKHR(m_physDev, &planeCount, planeProps.data());

    uint32_t planeIndex = UINT_MAX;
    for (uint32_t i = 0; i < planeCount; ++i) {
        uint32_t supportedDisplayCount = 0;
        err = m_getDisplayPlaneSupportedDisplaysKHR(m_physDev, i, &supportedDisplayCount, nullptr);
        if (err != VK_SUCCESS) {
            qWarning("Failed to query supported displays for plane: %d", err);
            return VK_NULL_HANDLE;
        }

        QVarLengthArray<VkDisplayKHR, 4> supportedDisplays(supportedDisplayCount);
        m_getDisplayPlaneSupportedDisplaysKHR(m_physDev, i, &supportedDisplayCount, supportedDisplays.data());
        qCDebug(qLcEglDevDebug, "Plane #%u supports %u displays, currently bound to display %p",
               i, supportedDisplayCount, (void *) planeProps[i].currentDisplay);

        VkDisplayPlaneCapabilitiesKHR caps;
        err = m_getDisplayPlaneCapabilitiesKHR(m_physDev, displayMode, i, &caps);
        if (err != VK_SUCCESS) {
            qWarning("Failed to query plane capabilities: %d", err);
            return VK_NULL_HANDLE;
        }

        qCDebug(qLcEglDevDebug, "  supportedAlpha: %d (1=no, 2=global, 4=per pixel, 8=per pixel premul)\n"
               "  minSrc=%d, %d %ux%u\n"
               "  maxSrc=%d, %d %ux%u\n"
               "  minDst=%d, %d %ux%u\n"
               "  maxDst=%d, %d %ux%u",
               int(caps.supportedAlpha),
               caps.minSrcPosition.x, caps.minSrcPosition.y, caps.minSrcExtent.width, caps.minSrcExtent.height,
               caps.maxSrcPosition.x, caps.maxSrcPosition.y, caps.maxSrcExtent.width, caps.maxSrcExtent.height,
               caps.minDstPosition.x, caps.minDstPosition.y, caps.minDstExtent.width, caps.minDstExtent.height,
               caps.maxDstPosition.x, caps.maxDstPosition.y, caps.maxDstExtent.width, caps.maxDstExtent.height);

        // if the plane is not in use and supports our chosen display, use that plane
        if (supportedDisplays.contains(display)
            && (planeProps[i].currentDisplay == VK_NULL_HANDLE || planeProps[i].currentDisplay == display))
        {
            planeIndex = i;
        }
    }

    if (planeIndex == UINT_MAX) {
        qWarning("Failed to find a suitable plane");
        return VK_NULL_HANDLE;
    }

    qCDebug(qLcEglDevDebug, "Using plane #%u", planeIndex);

    VkDisplaySurfaceCreateInfoKHR surfaceCreateInfo = {};
    surfaceCreateInfo.sType = VK_STRUCTURE_TYPE_DISPLAY_SURFACE_CREATE_INFO_KHR;
    surfaceCreateInfo.displayMode = displayMode;
    surfaceCreateInfo.planeIndex = planeIndex;
    surfaceCreateInfo.planeStackIndex = planeProps[planeIndex].currentStackIndex;
    surfaceCreateInfo.transform = VK_SURFACE_TRANSFORM_INHERIT_BIT_KHR;
    surfaceCreateInfo.globalAlpha = 1.0f;
    surfaceCreateInfo.alphaMode = VK_DISPLAY_PLANE_ALPHA_OPAQUE_BIT_KHR;
    surfaceCreateInfo.imageExtent = { width, height };

    VkSurfaceKHR surface = VK_NULL_HANDLE;
    err = m_createDisplayPlaneSurfaceKHR(m_vkInst, &surfaceCreateInfo, nullptr, &surface);
    if (err != VK_SUCCESS || surface == VK_NULL_HANDLE) {
        qWarning("Failed to create surface: %d", err);
        return VK_NULL_HANDLE;
    }

    qCDebug(qLcEglDevDebug, "Created surface %p", (void *) surface);

    return surface;

#else
    Q_UNUSED(window);
    qWarning("VK_KHR_display support was not compiled in, cannot create surface");
    return VK_NULL_HANDLE;
#endif
}

void QEglFSVulkanInstance::presentAboutToBeQueued(QWindow *window)
{
    // support QT_QPA_EGLFS_FORCEVSYNC (i.MX8 with eglfs_viv)
    qt_egl_device_integration()->waitForVSync(window->handle());
}

QT_END_NAMESPACE