hellovulkanwindow.cpp Example File

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  #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
  }