cefclient: Set recommended command-line switches for off-screen rendering

tests/cefclient/browser/client_app_browser.cc

@@ -6,12 +6,49 @@
 
 #include "include/base/cef_logging.h"
 #include "include/cef_cookie.h"
+#include "cefclient/common/client_switches.h"
 
 namespace client {
 
 ClientAppBrowser::ClientAppBrowser() {
 }
 
+void ClientAppBrowser::OnBeforeCommandLineProcessing(
+    const CefString& process_type,
+    CefRefPtr<CefCommandLine> command_line) {
+  // Pass additional command-line flags to the browser process.
+  if (process_type.empty()) {
+    // Pass additional command-line flags when off-screen rendering is enabled.
+    if (command_line->HasSwitch(switches::kOffScreenRenderingEnabled)) {
+      // If the PDF extension is enabled then cc Surfaces must be disabled for
+      // PDFs to render correctly.
+      // See https://bitbucket.org/chromiumembedded/cef/issues/1689 for details.
+      if (!command_line->HasSwitch("disable-extensions") &&
+          !command_line->HasSwitch("disable-pdf-extension")) {
+        command_line->AppendSwitch("disable-surfaces");
+      }
+
+      // Use software rendering and compositing (disable GPU) for increased FPS
+      // and decreased CPU usage. This will also disable WebGL so remove these
+      // switches if you need that capability.
+      // See https://bitbucket.org/chromiumembedded/cef/issues/1257 for details.
+      if (!command_line->HasSwitch(switches::kEnableGPU)) {
+        command_line->AppendSwitch("disable-gpu");
+        command_line->AppendSwitch("disable-gpu-compositing");
+      }
+
+      // Synchronize the frame rate between all processes. This results in
+      // decreased CPU usage by avoiding the generation of extra frames that
+      // would otherwise be discarded. The frame rate can be set at browser
+      // creation time via CefBrowserSettings.windowless_frame_rate or changed
+      // dynamically using CefBrowserHost::SetWindowlessFrameRate. In cefclient
+      // it can be set via the command-line using `--off-screen-frame-rate=XX`.
+      // See https://bitbucket.org/chromiumembedded/cef/issues/1368 for details.
+      command_line->AppendSwitch("enable-begin-frame-scheduling");
+    }
+  }
+}
+
 void ClientAppBrowser::OnContextInitialized() {
   CreateDelegates(delegates_);
 

tests/cefclient/browser/client_app_browser.h

@@ -46,6 +46,9 @@ class ClientAppBrowser : public ClientApp,
   static CefRefPtr<CefPrintHandler> CreatePrintHandler();
 
   // CefApp methods.
+  void OnBeforeCommandLineProcessing(
+      const CefString& process_type,
+      CefRefPtr<CefCommandLine> command_line) OVERRIDE;
   CefRefPtr<CefBrowserProcessHandler> GetBrowserProcessHandler() OVERRIDE {
     return this;
   }

tests/cefclient/common/client_switches.cc

@@ -27,6 +27,7 @@ const char kShowUpdateRect[] = "show-update-rect";
 const char kMouseCursorChangeDisabled[] = "mouse-cursor-change-disabled";
 const char kRequestContextPerBrowser[] = "request-context-per-browser";
 const char kBackgroundColor[] = "background-color";
+const char kEnableGPU[] = "enable-gpu";
 
 }  // namespace switches
 }  // namespace client

tests/cefclient/common/client_switches.h

@@ -21,6 +21,7 @@ extern const char kShowUpdateRect[];
 extern const char kMouseCursorChangeDisabled[];
 extern const char kRequestContextPerBrowser[];
 extern const char kBackgroundColor[];
+extern const char kEnableGPU[];
 
 }  // namespace switches
 }  // namespace client