feat(win): new capture method, Windows.Graphics.Capture (#2580)

src/platform/windows/display_vram.cpp

@@ -945,9 +945,8 @@ namespace platf::dxgi {
   }
 
   capture_e
-  display_vram_t::snapshot(const pull_free_image_cb_t &pull_free_image_cb, std::shared_ptr<platf::img_t> &img_out, std::chrono::milliseconds timeout, bool cursor_visible) {
+  display_ddup_vram_t::snapshot(const pull_free_image_cb_t &pull_free_image_cb, std::shared_ptr<platf::img_t> &img_out, std::chrono::milliseconds timeout, bool cursor_visible) {
     HRESULT status;
-
     DXGI_OUTDUPL_FRAME_INFO frame_info;
 
     resource_t::pointer res_p {};
@@ -1329,9 +1328,14 @@ namespace platf::dxgi {
     return capture_e::ok;
   }
 
+  capture_e
+  display_ddup_vram_t::release_snapshot() {
+    return dup.release_frame();
+  }
+
   int
-  display_vram_t::init(const ::video::config_t &config, const std::string &display_name) {
-    if (display_base_t::init(config, display_name)) {
+  display_ddup_vram_t::init(const ::video::config_t &config, const std::string &display_name) {
+    if (display_base_t::init(config, display_name) || dup.init(this, config)) {
       return -1;
     }
 
@@ -1410,6 +1414,80 @@ namespace platf::dxgi {
     return 0;
   }
 
+  /**
+   * Get the next frame from the Windows.Graphics.Capture API and copy it into a new snapshot texture.
+   * @param pull_free_image_cb call this to get a new free image from the video subsystem.
+   * @param img_out the captured frame is returned here
+   * @param timeout how long to wait for the next frame
+   * @param cursor_visible
+   */
+  capture_e
+  display_wgc_vram_t::snapshot(const pull_free_image_cb_t &pull_free_image_cb, std::shared_ptr<platf::img_t> &img_out, std::chrono::milliseconds timeout, bool cursor_visible) {
+    texture2d_t src;
+    uint64_t frame_qpc;
+    dup.set_cursor_visible(cursor_visible);
+    auto capture_status = dup.next_frame(timeout, &src, frame_qpc);
+    if (capture_status != capture_e::ok)
+      return capture_status;
+
+    auto frame_timestamp = std::chrono::steady_clock::now() - qpc_time_difference(qpc_counter(), frame_qpc);
+    D3D11_TEXTURE2D_DESC desc;
+    src->GetDesc(&desc);
+
+    // It's possible for our display enumeration to race with mode changes and result in
+    // mismatched image pool and desktop texture sizes. If this happens, just reinit again.
+    if (desc.Width != width_before_rotation || desc.Height != height_before_rotation) {
+      BOOST_LOG(info) << "Capture size changed ["sv << width << 'x' << height << " -> "sv << desc.Width << 'x' << desc.Height << ']';
+      return capture_e::reinit;
+    }
+
+    // It's also possible for the capture format to change on the fly. If that happens,
+    // reinitialize capture to try format detection again and create new images.
+    if (capture_format != desc.Format) {
+      BOOST_LOG(info) << "Capture format changed ["sv << dxgi_format_to_string(capture_format) << " -> "sv << dxgi_format_to_string(desc.Format) << ']';
+      return capture_e::reinit;
+    }
+
+    std::shared_ptr<platf::img_t> img;
+    if (!pull_free_image_cb(img))
+      return capture_e::interrupted;
+
+    auto d3d_img = std::static_pointer_cast<img_d3d_t>(img);
+    d3d_img->blank = false;  // image is always ready for capture
+    if (complete_img(d3d_img.get(), false) == 0) {
+      texture_lock_helper lock_helper(d3d_img->capture_mutex.get());
+      if (lock_helper.lock()) {
+        device_ctx->CopyResource(d3d_img->capture_texture.get(), src.get());
+      }
+      else {
+        BOOST_LOG(error) << "Failed to lock capture texture";
+        return capture_e::error;
+      }
+    }
+    else {
+      return capture_e::error;
+    }
+    img_out = img;
+    if (img_out) {
+      img_out->frame_timestamp = frame_timestamp;
+    }
+
+    return capture_e::ok;
+  }
+
+  capture_e
+  display_wgc_vram_t::release_snapshot() {
+    return dup.release_frame();
+  }
+
+  int
+  display_wgc_vram_t::init(const ::video::config_t &config, const std::string &display_name) {
+    if (display_base_t::init(config, display_name) || dup.init(this, config))
+      return -1;
+
+    return 0;
+  }
+
   std::shared_ptr<platf::img_t>
   display_vram_t::alloc_img() {
     auto img = std::make_shared<img_d3d_t>();