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50
51#include "trianglerenderer.h"
52#include <QVulkanFunctions>
53#include <QFile>
54
55// Note that the vertex data and the projection matrix assume OpenGL. With
56// Vulkan Y is negated in clip space and the near/far plane is at 0/1 instead
57// of -1/1. These will be corrected for by an extra transformation when
58// calculating the modelview-projection matrix.
59static float vertexData[] = { // Y up, front = CCW
60 0.0f, 0.5f, 1.0f, 0.0f, 0.0f,
61 -0.5f, -0.5f, 0.0f, 1.0f, 0.0f,
62 0.5f, -0.5f, 0.0f, 0.0f, 1.0f
63};
64
65static const int UNIFORM_DATA_SIZE = 16 * sizeof(float);
66
67static inline VkDeviceSize aligned(VkDeviceSize v, VkDeviceSize byteAlign)
68{
69 return (v + byteAlign - 1) & ~(byteAlign - 1);
70}
71
72TriangleRenderer::TriangleRenderer(QVulkanWindow *w, bool msaa)
73 : m_window(w)
74{
75 if (msaa) {
76 const QVector<int> counts = w->supportedSampleCounts();
77 qDebug() << "Supported sample counts:" << counts;
78 for (int s = 16; s >= 4; s /= 2) {
79 if (counts.contains(t: s)) {
80 qDebug(msg: "Requesting sample count %d", s);
81 m_window->setSampleCount(s);
82 break;
83 }
84 }
85 }
86}
87
88VkShaderModule TriangleRenderer::createShader(const QString &name)
89{
90 QFile file(name);
91 if (!file.open(flags: QIODevice::ReadOnly)) {
92 qWarning(msg: "Failed to read shader %s", qPrintable(name));
93 return VK_NULL_HANDLE;
94 }
95 QByteArray blob = file.readAll();
96 file.close();
97
98 VkShaderModuleCreateInfo shaderInfo;
99 memset(s: &shaderInfo, c: 0, n: sizeof(shaderInfo));
100 shaderInfo.sType = VK_STRUCTURE_TYPE_SHADER_MODULE_CREATE_INFO;
101 shaderInfo.codeSize = blob.size();
102 shaderInfo.pCode = reinterpret_cast<const uint32_t *>(blob.constData());
103 VkShaderModule shaderModule;
104 VkResult err = m_devFuncs->vkCreateShaderModule(m_window->device(), &shaderInfo, nullptr, &shaderModule);
105 if (err != VK_SUCCESS) {
106 qWarning(msg: "Failed to create shader module: %d", err);
107 return VK_NULL_HANDLE;
108 }
109
110 return shaderModule;
111}
112
113void TriangleRenderer::initResources()
114{
115 qDebug(msg: "initResources");
116
117 VkDevice dev = m_window->device();
118 m_devFuncs = m_window->vulkanInstance()->deviceFunctions(device: dev);
119
120 // Prepare the vertex and uniform data. The vertex data will never
121 // change so one buffer is sufficient regardless of the value of
122 // QVulkanWindow::CONCURRENT_FRAME_COUNT. Uniform data is changing per
123 // frame however so active frames have to have a dedicated copy.
124
125 // Use just one memory allocation and one buffer. We will then specify the
126 // appropriate offsets for uniform buffers in the VkDescriptorBufferInfo.
127 // Have to watch out for
128 // VkPhysicalDeviceLimits::minUniformBufferOffsetAlignment, though.
129
130 // The uniform buffer is not strictly required in this example, we could
131 // have used push constants as well since our single matrix (64 bytes) fits
132 // into the spec mandated minimum limit of 128 bytes. However, once that
133 // limit is not sufficient, the per-frame buffers, as shown below, will
134 // become necessary.
135
136 const int concurrentFrameCount = m_window->concurrentFrameCount();
137 const VkPhysicalDeviceLimits *pdevLimits = &m_window->physicalDeviceProperties()->limits;
138 const VkDeviceSize uniAlign = pdevLimits->minUniformBufferOffsetAlignment;
139 qDebug(msg: "uniform buffer offset alignment is %u", (uint) uniAlign);
140 VkBufferCreateInfo bufInfo;
141 memset(s: &bufInfo, c: 0, n: sizeof(bufInfo));
142 bufInfo.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
143 // Our internal layout is vertex, uniform, uniform, ... with each uniform buffer start offset aligned to uniAlign.
144 const VkDeviceSize vertexAllocSize = aligned(v: sizeof(vertexData), byteAlign: uniAlign);
145 const VkDeviceSize uniformAllocSize = aligned(v: UNIFORM_DATA_SIZE, byteAlign: uniAlign);
146 bufInfo.size = vertexAllocSize + concurrentFrameCount * uniformAllocSize;
147 bufInfo.usage = VK_BUFFER_USAGE_VERTEX_BUFFER_BIT | VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT;
148
149 VkResult err = m_devFuncs->vkCreateBuffer(dev, &bufInfo, nullptr, &m_buf);
150 if (err != VK_SUCCESS)
151 qFatal(msg: "Failed to create buffer: %d", err);
152
153 VkMemoryRequirements memReq;
154 m_devFuncs->vkGetBufferMemoryRequirements(dev, m_buf, &memReq);
155
156 VkMemoryAllocateInfo memAllocInfo = {
157 .sType: VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO,
158 .pNext: nullptr,
159 .allocationSize: memReq.size,
160 .memoryTypeIndex: m_window->hostVisibleMemoryIndex()
161 };
162
163 err = m_devFuncs->vkAllocateMemory(dev, &memAllocInfo, nullptr, &m_bufMem);
164 if (err != VK_SUCCESS)
165 qFatal(msg: "Failed to allocate memory: %d", err);
166
167 err = m_devFuncs->vkBindBufferMemory(dev, m_buf, m_bufMem, 0);
168 if (err != VK_SUCCESS)
169 qFatal(msg: "Failed to bind buffer memory: %d", err);
170
171 quint8 *p;
172 err = m_devFuncs->vkMapMemory(dev, m_bufMem, 0, memReq.size, 0, reinterpret_cast<void **>(&p));
173 if (err != VK_SUCCESS)
174 qFatal(msg: "Failed to map memory: %d", err);
175 memcpy(dest: p, src: vertexData, n: sizeof(vertexData));
176 QMatrix4x4 ident;
177 memset(s: m_uniformBufInfo, c: 0, n: sizeof(m_uniformBufInfo));
178 for (int i = 0; i < concurrentFrameCount; ++i) {
179 const VkDeviceSize offset = vertexAllocSize + i * uniformAllocSize;
180 memcpy(dest: p + offset, src: ident.constData(), n: 16 * sizeof(float));
181 m_uniformBufInfo[i].buffer = m_buf;
182 m_uniformBufInfo[i].offset = offset;
183 m_uniformBufInfo[i].range = uniformAllocSize;
184 }
185 m_devFuncs->vkUnmapMemory(dev, m_bufMem);
186
187 VkVertexInputBindingDescription vertexBindingDesc = {
188 .binding: 0, // binding
189 .stride: 5 * sizeof(float),
190 .inputRate: VK_VERTEX_INPUT_RATE_VERTEX
191 };
192 VkVertexInputAttributeDescription vertexAttrDesc[] = {
193 { // position
194 .location: 0, // location
195 .binding: 0, // binding
196 .format: VK_FORMAT_R32G32_SFLOAT,
197 .offset: 0
198 },
199 { // color
200 .location: 1,
201 .binding: 0,
202 .format: VK_FORMAT_R32G32B32_SFLOAT,
203 .offset: 2 * sizeof(float)
204 }
205 };
206
207 VkPipelineVertexInputStateCreateInfo vertexInputInfo;
208 vertexInputInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
209 vertexInputInfo.pNext = nullptr;
210 vertexInputInfo.flags = 0;
211 vertexInputInfo.vertexBindingDescriptionCount = 1;
212 vertexInputInfo.pVertexBindingDescriptions = &vertexBindingDesc;
213 vertexInputInfo.vertexAttributeDescriptionCount = 2;
214 vertexInputInfo.pVertexAttributeDescriptions = vertexAttrDesc;
215
216 // Set up descriptor set and its layout.
217 VkDescriptorPoolSize descPoolSizes = { .type: VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, .descriptorCount: uint32_t(concurrentFrameCount) };
218 VkDescriptorPoolCreateInfo descPoolInfo;
219 memset(s: &descPoolInfo, c: 0, n: sizeof(descPoolInfo));
220 descPoolInfo.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO;
221 descPoolInfo.maxSets = concurrentFrameCount;
222 descPoolInfo.poolSizeCount = 1;
223 descPoolInfo.pPoolSizes = &descPoolSizes;
224 err = m_devFuncs->vkCreateDescriptorPool(dev, &descPoolInfo, nullptr, &m_descPool);
225 if (err != VK_SUCCESS)
226 qFatal(msg: "Failed to create descriptor pool: %d", err);
227
228 VkDescriptorSetLayoutBinding layoutBinding = {
229 .binding: 0, // binding
230 .descriptorType: VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
231 .descriptorCount: 1,
232 .stageFlags: VK_SHADER_STAGE_VERTEX_BIT,
233 .pImmutableSamplers: nullptr
234 };
235 VkDescriptorSetLayoutCreateInfo descLayoutInfo = {
236 .sType: VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO,
237 .pNext: nullptr,
238 .flags: 0,
239 .bindingCount: 1,
240 .pBindings: &layoutBinding
241 };
242 err = m_devFuncs->vkCreateDescriptorSetLayout(dev, &descLayoutInfo, nullptr, &m_descSetLayout);
243 if (err != VK_SUCCESS)
244 qFatal(msg: "Failed to create descriptor set layout: %d", err);
245
246 for (int i = 0; i < concurrentFrameCount; ++i) {
247 VkDescriptorSetAllocateInfo descSetAllocInfo = {
248 .sType: VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO,
249 .pNext: nullptr,
250 .descriptorPool: m_descPool,
251 .descriptorSetCount: 1,
252 .pSetLayouts: &m_descSetLayout
253 };
254 err = m_devFuncs->vkAllocateDescriptorSets(dev, &descSetAllocInfo, &m_descSet[i]);
255 if (err != VK_SUCCESS)
256 qFatal(msg: "Failed to allocate descriptor set: %d", err);
257
258 VkWriteDescriptorSet descWrite;
259 memset(s: &descWrite, c: 0, n: sizeof(descWrite));
260 descWrite.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
261 descWrite.dstSet = m_descSet[i];
262 descWrite.descriptorCount = 1;
263 descWrite.descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER;
264 descWrite.pBufferInfo = &m_uniformBufInfo[i];
265 m_devFuncs->vkUpdateDescriptorSets(dev, 1, &descWrite, 0, nullptr);
266 }
267
268 // Pipeline cache
269 VkPipelineCacheCreateInfo pipelineCacheInfo;
270 memset(s: &pipelineCacheInfo, c: 0, n: sizeof(pipelineCacheInfo));
271 pipelineCacheInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_CACHE_CREATE_INFO;
272 err = m_devFuncs->vkCreatePipelineCache(dev, &pipelineCacheInfo, nullptr, &m_pipelineCache);
273 if (err != VK_SUCCESS)
274 qFatal(msg: "Failed to create pipeline cache: %d", err);
275
276 // Pipeline layout
277 VkPipelineLayoutCreateInfo pipelineLayoutInfo;
278 memset(s: &pipelineLayoutInfo, c: 0, n: sizeof(pipelineLayoutInfo));
279 pipelineLayoutInfo.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
280 pipelineLayoutInfo.setLayoutCount = 1;
281 pipelineLayoutInfo.pSetLayouts = &m_descSetLayout;
282 err = m_devFuncs->vkCreatePipelineLayout(dev, &pipelineLayoutInfo, nullptr, &m_pipelineLayout);
283 if (err != VK_SUCCESS)
284 qFatal(msg: "Failed to create pipeline layout: %d", err);
285
286 // Shaders
287 VkShaderModule vertShaderModule = createShader(QStringLiteral(":/color_vert.spv"));
288 VkShaderModule fragShaderModule = createShader(QStringLiteral(":/color_frag.spv"));
289
290 // Graphics pipeline
291 VkGraphicsPipelineCreateInfo pipelineInfo;
292 memset(s: &pipelineInfo, c: 0, n: sizeof(pipelineInfo));
293 pipelineInfo.sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO;
294
295 VkPipelineShaderStageCreateInfo shaderStages[2] = {
296 {
297 .sType: VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO,
298 .pNext: nullptr,
299 .flags: 0,
300 .stage: VK_SHADER_STAGE_VERTEX_BIT,
301 .module: vertShaderModule,
302 .pName: "main",
303 .pSpecializationInfo: nullptr
304 },
305 {
306 .sType: VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO,
307 .pNext: nullptr,
308 .flags: 0,
309 .stage: VK_SHADER_STAGE_FRAGMENT_BIT,
310 .module: fragShaderModule,
311 .pName: "main",
312 .pSpecializationInfo: nullptr
313 }
314 };
315 pipelineInfo.stageCount = 2;
316 pipelineInfo.pStages = shaderStages;
317
318 pipelineInfo.pVertexInputState = &vertexInputInfo;
319
320 VkPipelineInputAssemblyStateCreateInfo ia;
321 memset(s: &ia, c: 0, n: sizeof(ia));
322 ia.sType = VK_STRUCTURE_TYPE_PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO;
323 ia.topology = VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST;
324 pipelineInfo.pInputAssemblyState = &ia;
325
326 // The viewport and scissor will be set dynamically via vkCmdSetViewport/Scissor.
327 // This way the pipeline does not need to be touched when resizing the window.
328 VkPipelineViewportStateCreateInfo vp;
329 memset(s: &vp, c: 0, n: sizeof(vp));
330 vp.sType = VK_STRUCTURE_TYPE_PIPELINE_VIEWPORT_STATE_CREATE_INFO;
331 vp.viewportCount = 1;
332 vp.scissorCount = 1;
333 pipelineInfo.pViewportState = &vp;
334
335 VkPipelineRasterizationStateCreateInfo rs;
336 memset(s: &rs, c: 0, n: sizeof(rs));
337 rs.sType = VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_CREATE_INFO;
338 rs.polygonMode = VK_POLYGON_MODE_FILL;
339 rs.cullMode = VK_CULL_MODE_NONE; // we want the back face as well
340 rs.frontFace = VK_FRONT_FACE_COUNTER_CLOCKWISE;
341 rs.lineWidth = 1.0f;
342 pipelineInfo.pRasterizationState = &rs;
343
344 VkPipelineMultisampleStateCreateInfo ms;
345 memset(s: &ms, c: 0, n: sizeof(ms));
346 ms.sType = VK_STRUCTURE_TYPE_PIPELINE_MULTISAMPLE_STATE_CREATE_INFO;
347 // Enable multisampling.
348 ms.rasterizationSamples = m_window->sampleCountFlagBits();
349 pipelineInfo.pMultisampleState = &ms;
350
351 VkPipelineDepthStencilStateCreateInfo ds;
352 memset(s: &ds, c: 0, n: sizeof(ds));
353 ds.sType = VK_STRUCTURE_TYPE_PIPELINE_DEPTH_STENCIL_STATE_CREATE_INFO;
354 ds.depthTestEnable = VK_TRUE;
355 ds.depthWriteEnable = VK_TRUE;
356 ds.depthCompareOp = VK_COMPARE_OP_LESS_OR_EQUAL;
357 pipelineInfo.pDepthStencilState = &ds;
358
359 VkPipelineColorBlendStateCreateInfo cb;
360 memset(s: &cb, c: 0, n: sizeof(cb));
361 cb.sType = VK_STRUCTURE_TYPE_PIPELINE_COLOR_BLEND_STATE_CREATE_INFO;
362 // no blend, write out all of rgba
363 VkPipelineColorBlendAttachmentState att;
364 memset(s: &att, c: 0, n: sizeof(att));
365 att.colorWriteMask = 0xF;
366 cb.attachmentCount = 1;
367 cb.pAttachments = &att;
368 pipelineInfo.pColorBlendState = &cb;
369
370 VkDynamicState dynEnable[] = { VK_DYNAMIC_STATE_VIEWPORT, VK_DYNAMIC_STATE_SCISSOR };
371 VkPipelineDynamicStateCreateInfo dyn;
372 memset(s: &dyn, c: 0, n: sizeof(dyn));
373 dyn.sType = VK_STRUCTURE_TYPE_PIPELINE_DYNAMIC_STATE_CREATE_INFO;
374 dyn.dynamicStateCount = sizeof(dynEnable) / sizeof(VkDynamicState);
375 dyn.pDynamicStates = dynEnable;
376 pipelineInfo.pDynamicState = &dyn;
377
378 pipelineInfo.layout = m_pipelineLayout;
379 pipelineInfo.renderPass = m_window->defaultRenderPass();
380
381 err = m_devFuncs->vkCreateGraphicsPipelines(dev, m_pipelineCache, 1, &pipelineInfo, nullptr, &m_pipeline);
382 if (err != VK_SUCCESS)
383 qFatal(msg: "Failed to create graphics pipeline: %d", err);
384
385 if (vertShaderModule)
386 m_devFuncs->vkDestroyShaderModule(dev, vertShaderModule, nullptr);
387 if (fragShaderModule)
388 m_devFuncs->vkDestroyShaderModule(dev, fragShaderModule, nullptr);
389}
390
391void TriangleRenderer::initSwapChainResources()
392{
393 qDebug(msg: "initSwapChainResources");
394
395 // Projection matrix
396 m_proj = m_window->clipCorrectionMatrix(); // adjust for Vulkan-OpenGL clip space differences
397 const QSize sz = m_window->swapChainImageSize();
398 m_proj.perspective(verticalAngle: 45.0f, aspectRatio: sz.width() / (float) sz.height(), nearPlane: 0.01f, farPlane: 100.0f);
399 m_proj.translate(x: 0, y: 0, z: -4);
400}
401
402void TriangleRenderer::releaseSwapChainResources()
403{
404 qDebug(msg: "releaseSwapChainResources");
405}
406
407void TriangleRenderer::releaseResources()
408{
409 qDebug(msg: "releaseResources");
410
411 VkDevice dev = m_window->device();
412
413 if (m_pipeline) {
414 m_devFuncs->vkDestroyPipeline(dev, m_pipeline, nullptr);
415 m_pipeline = VK_NULL_HANDLE;
416 }
417
418 if (m_pipelineLayout) {
419 m_devFuncs->vkDestroyPipelineLayout(dev, m_pipelineLayout, nullptr);
420 m_pipelineLayout = VK_NULL_HANDLE;
421 }
422
423 if (m_pipelineCache) {
424 m_devFuncs->vkDestroyPipelineCache(dev, m_pipelineCache, nullptr);
425 m_pipelineCache = VK_NULL_HANDLE;
426 }
427
428 if (m_descSetLayout) {
429 m_devFuncs->vkDestroyDescriptorSetLayout(dev, m_descSetLayout, nullptr);
430 m_descSetLayout = VK_NULL_HANDLE;
431 }
432
433 if (m_descPool) {
434 m_devFuncs->vkDestroyDescriptorPool(dev, m_descPool, nullptr);
435 m_descPool = VK_NULL_HANDLE;
436 }
437
438 if (m_buf) {
439 m_devFuncs->vkDestroyBuffer(dev, m_buf, nullptr);
440 m_buf = VK_NULL_HANDLE;
441 }
442
443 if (m_bufMem) {
444 m_devFuncs->vkFreeMemory(dev, m_bufMem, nullptr);
445 m_bufMem = VK_NULL_HANDLE;
446 }
447}
448
449void TriangleRenderer::startNextFrame()
450{
451 VkDevice dev = m_window->device();
452 VkCommandBuffer cb = m_window->currentCommandBuffer();
453 const QSize sz = m_window->swapChainImageSize();
454
455 VkClearColorValue clearColor = {.float32: { 0, 0, 0, 1 }};
456 VkClearDepthStencilValue clearDS = { .depth: 1, .stencil: 0 };
457 VkClearValue clearValues[3];
458 memset(s: clearValues, c: 0, n: sizeof(clearValues));
459 clearValues[0].color = clearValues[2].color = clearColor;
460 clearValues[1].depthStencil = clearDS;
461
462 VkRenderPassBeginInfo rpBeginInfo;
463 memset(s: &rpBeginInfo, c: 0, n: sizeof(rpBeginInfo));
464 rpBeginInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
465 rpBeginInfo.renderPass = m_window->defaultRenderPass();
466 rpBeginInfo.framebuffer = m_window->currentFramebuffer();
467 rpBeginInfo.renderArea.extent.width = sz.width();
468 rpBeginInfo.renderArea.extent.height = sz.height();
469 rpBeginInfo.clearValueCount = m_window->sampleCountFlagBits() > VK_SAMPLE_COUNT_1_BIT ? 3 : 2;
470 rpBeginInfo.pClearValues = clearValues;
471 VkCommandBuffer cmdBuf = m_window->currentCommandBuffer();
472 m_devFuncs->vkCmdBeginRenderPass(cmdBuf, &rpBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
473
474 quint8 *p;
475 VkResult err = m_devFuncs->vkMapMemory(dev, m_bufMem, m_uniformBufInfo[m_window->currentFrame()].offset,
476 UNIFORM_DATA_SIZE, 0, reinterpret_cast<void **>(&p));
477 if (err != VK_SUCCESS)
478 qFatal(msg: "Failed to map memory: %d", err);
479 QMatrix4x4 m = m_proj;
480 m.rotate(angle: m_rotation, x: 0, y: 1, z: 0);
481 memcpy(dest: p, src: m.constData(), n: 16 * sizeof(float));
482 m_devFuncs->vkUnmapMemory(dev, m_bufMem);
483
484 // Not exactly a real animation system, just advance on every frame for now.
485 m_rotation += 1.0f;
486
487 m_devFuncs->vkCmdBindPipeline(cb, VK_PIPELINE_BIND_POINT_GRAPHICS, m_pipeline);
488 m_devFuncs->vkCmdBindDescriptorSets(cb, VK_PIPELINE_BIND_POINT_GRAPHICS, m_pipelineLayout, 0, 1,
489 &m_descSet[m_window->currentFrame()], 0, nullptr);
490 VkDeviceSize vbOffset = 0;
491 m_devFuncs->vkCmdBindVertexBuffers(cb, 0, 1, &m_buf, &vbOffset);
492
493 VkViewport viewport;
494 viewport.x = viewport.y = 0;
495 viewport.width = sz.width();
496 viewport.height = sz.height();
497 viewport.minDepth = 0;
498 viewport.maxDepth = 1;
499 m_devFuncs->vkCmdSetViewport(cb, 0, 1, &viewport);
500
501 VkRect2D scissor;
502 scissor.offset.x = scissor.offset.y = 0;
503 scissor.extent.width = viewport.width;
504 scissor.extent.height = viewport.height;
505 m_devFuncs->vkCmdSetScissor(cb, 0, 1, &scissor);
506
507 m_devFuncs->vkCmdDraw(cb, 3, 1, 0, 0);
508
509 m_devFuncs->vkCmdEndRenderPass(cmdBuf);
510
511 m_window->frameReady();
512 m_window->requestUpdate(); // render continuously, throttled by the presentation rate
513}
514

source code of qtbase/examples/vulkan/shared/trianglerenderer.cpp