Flutter Impeller
vulkan_screenshotter.mm
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
6 
7 #include "flutter/fml/synchronization/waitable_event.h"
9 #define GLFW_INCLUDE_NONE
10 #include "third_party/glfw/include/GLFW/glfw3.h"
11 
12 namespace impeller {
13 namespace testing {
14 
15 namespace {
16 
18  decltype(&CGContextRelease)>;
20  decltype(&CGImageRelease)>;
21 using CGColorSpacePtr =
23  decltype(&CGColorSpaceRelease)>;
24 
25 std::unique_ptr<Screenshot> ReadTexture(
26  const std::shared_ptr<Context>& surface_context,
27  const std::shared_ptr<Texture>& texture) {
28  DeviceBufferDescriptor buffer_desc;
29  buffer_desc.storage_mode = StorageMode::kHostVisible;
30  buffer_desc.size =
31  texture->GetTextureDescriptor().GetByteSizeOfBaseMipLevel();
32  buffer_desc.readback = true;
33  std::shared_ptr<DeviceBuffer> device_buffer =
34  surface_context->GetResourceAllocator()->CreateBuffer(buffer_desc);
35  FML_CHECK(device_buffer);
36 
37  auto command_buffer = surface_context->CreateCommandBuffer();
38  auto blit_pass = command_buffer->CreateBlitPass();
39  bool success = blit_pass->AddCopy(texture, device_buffer);
40  FML_CHECK(success);
41 
42  success = blit_pass->EncodeCommands();
43  FML_CHECK(success);
44 
45  fml::AutoResetWaitableEvent latch;
46  success =
47  surface_context->GetCommandQueue()
48  ->Submit({command_buffer},
49  [&latch](CommandBuffer::Status status) {
50  FML_CHECK(status == CommandBuffer::Status::kCompleted);
51  latch.Signal();
52  })
53  .ok();
54  FML_CHECK(success);
55  latch.Wait();
56  device_buffer->Invalidate();
57 
58  // TODO(gaaclarke): Replace CoreImage requirement with something
59  // crossplatform.
60 
61  CGColorSpacePtr color_space(CGColorSpaceCreateDeviceRGB(),
62  &CGColorSpaceRelease);
63  CGBitmapInfo bitmap_info =
64  texture->GetTextureDescriptor().format == PixelFormat::kB8G8R8A8UNormInt
65  ? kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Little
66  : kCGImageAlphaPremultipliedLast;
67  CGContextPtr context(
68  CGBitmapContextCreate(
69  device_buffer->OnGetContents(), texture->GetSize().width,
70  texture->GetSize().height,
71  /*bitsPerComponent=*/8,
72  /*bytesPerRow=*/texture->GetTextureDescriptor().GetBytesPerRow(),
73  color_space.get(), bitmap_info),
74  &CGContextRelease);
75  FML_CHECK(context);
76  CGImagePtr image(CGBitmapContextCreateImage(context.get()), &CGImageRelease);
77  FML_CHECK(image);
78 
79  return std::make_unique<MetalScreenshot>(image.release());
80 }
81 } // namespace
82 
84  const std::unique_ptr<PlaygroundImpl>& playground)
85  : playground_(playground) {
86  FML_CHECK(playground_);
87 }
88 
89 std::unique_ptr<Screenshot> VulkanScreenshotter::MakeScreenshot(
90  AiksContext& aiks_context,
91  const std::shared_ptr<Texture> texture) {
92  return ReadTexture(aiks_context.GetContext(), texture);
93 }
94 
95 } // namespace testing
96 } // namespace impeller
GLenum type
std::shared_ptr< Context > GetContext() const
Definition: aiks_context.cc:38
VulkanScreenshotter(const std::unique_ptr< PlaygroundImpl > &playground)
std::unique_ptr< Screenshot > MakeScreenshot(AiksContext &aiks_context, const std::shared_ptr< Texture > texture) override