Hello Vulkan Cubes Example

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#include "shader.h"
#include <QtConcurrentRun>
#include <QFile>
#include <QVulkanDeviceFunctions>

void Shader::load(QVulkanInstance *inst, VkDevice dev, const QString &fn)
{
    reset();
    m_maybeRunning = true;
    m_future = QtConcurrent::run([inst, dev, fn]() {
        ShaderData sd;
        QFile f(fn);
        if (!f.open(QIODevice::ReadOnly)) {
            qWarning("Failed to open %s", qPrintable(fn));
            return sd;
        }
        QByteArray blob = f.readAll();
        VkShaderModuleCreateInfo shaderInfo;
        memset(&shaderInfo, 0, sizeof(shaderInfo));
        shaderInfo.sType = VK_STRUCTURE_TYPE_SHADER_MODULE_CREATE_INFO;
        shaderInfo.codeSize = blob.size();
        shaderInfo.pCode = reinterpret_cast<const uint32_t *>(blob.constData());
        VkResult err = inst->deviceFunctions(dev)->vkCreateShaderModule(dev, &shaderInfo, nullptr, &sd.shaderModule);
        if (err != VK_SUCCESS) {
            qWarning("Failed to create shader module: %d", err);
            return sd;
        }
        return sd;
    });
}

ShaderData *Shader::data()
{
    if (m_maybeRunning && !m_data.isValid())
        m_data = m_future.result();

    return &m_data;
}

void Shader::reset()
{
    *data() = ShaderData();
    m_maybeRunning = false;
}