hellovulkanwindow.cpp Example File | Qt GUI 5.12.10

- Qt 5.12
- Qt GUI
- Hello Vulkan Window Example
- hellovulkanwindow.cpp Example File
- Qt 5.12.10 Reference Documentation

# hellovulkanwindow.cpp Example File

hellovulkanwindow/hellovulkanwindow.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2017 The Qt Company Ltd.
     ** Contact: https://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** 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.
     **
     ** BSD License Usage
     ** Alternatively, you may use this file under the terms of the BSD license
     ** as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of The Qt Company Ltd nor the names of its
     **     contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
     **
     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #include "hellovulkanwindow.h"
     #include <QVulkanFunctions>

     QVulkanWindowRenderer *VulkanWindow::createRenderer()
     {
         return new VulkanRenderer(this);
     }

     VulkanRenderer::VulkanRenderer(QVulkanWindow *w)
         : m_window(w)
     {
     }

     void VulkanRenderer::initResources()
     {
         qDebug("initResources");

         m_devFuncs = m_window->vulkanInstance()->deviceFunctions(m_window->device());
     }

     void VulkanRenderer::initSwapChainResources()
     {
         qDebug("initSwapChainResources");
     }

     void VulkanRenderer::releaseSwapChainResources()
     {
         qDebug("releaseSwapChainResources");
     }

     void VulkanRenderer::releaseResources()
     {
         qDebug("releaseResources");
     }

     void VulkanRenderer::startNextFrame()
     {
         m_green += 0.005f;
         if (m_green > 1.0f)
             m_green = 0.0f;

         VkClearColorValue clearColor = {{ 0.0f, m_green, 0.0f, 1.0f }};
         VkClearDepthStencilValue clearDS = { 1.0f, 0 };
         VkClearValue clearValues[2];
         memset(clearValues, 0, sizeof(clearValues));
         clearValues[0].color = clearColor;
         clearValues[1].depthStencil = clearDS;

         VkRenderPassBeginInfo rpBeginInfo;
         memset(&rpBeginInfo, 0, sizeof(rpBeginInfo));
         rpBeginInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
         rpBeginInfo.renderPass = m_window->defaultRenderPass();
         rpBeginInfo.framebuffer = m_window->currentFramebuffer();
         const QSize sz = m_window->swapChainImageSize();
         rpBeginInfo.renderArea.extent.width = sz.width();
         rpBeginInfo.renderArea.extent.height = sz.height();
         rpBeginInfo.clearValueCount = 2;
         rpBeginInfo.pClearValues = clearValues;
         VkCommandBuffer cmdBuf = m_window->currentCommandBuffer();
         m_devFuncs->vkCmdBeginRenderPass(cmdBuf, &rpBeginInfo, VK_SUBPASS_CONTENTS_INLINE);

         // Do nothing else. We will just clear to green, changing the component on
         // every invocation. This also helps verifying the rate to which the thread
         // is throttled to. (The elapsed time between startNextFrame calls should
         // typically be around 16 ms. Note that rendering is 2 frames ahead of what
         // is displayed.)

         m_devFuncs->vkCmdEndRenderPass(cmdBuf);

         m_window->frameReady();
         m_window->requestUpdate(); // render continuously, throttled by the presentation rate
     }