1 files changed, 111 insertions, 0 deletions
diff --git a/gfx/thebes/PrintTargetRecording.cpp b/gfx/thebes/PrintTargetRecording.cpp
new file mode 100644
index 0000000000..4d73995184
--- /dev/null
+++ b/gfx/thebes/PrintTargetRecording.cpp
@@ -0,0 +1,111 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "PrintTargetRecording.h"
+
+#include "cairo.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/Logging.h"
+
+namespace mozilla {
+namespace gfx {
+
+PrintTargetRecording::PrintTargetRecording(cairo_surface_t* aCairoSurface,
+                                           const IntSize& aSize)
+    : PrintTarget(aCairoSurface, aSize) {}
+
+/* static */
+already_AddRefed<PrintTargetRecording> PrintTargetRecording::CreateOrNull(
+    const IntSize& aSize) {
+  if (!Factory::CheckSurfaceSize(aSize)) {
+    return nullptr;
+  }
+
+  // Perhaps surprisingly, this surface is never actually drawn to.  This class
+  // creates a DrawTargetRecording using CreateRecordingDrawTarget, and
+  // that needs another DrawTarget to be passed to it.  You might expect the
+  // type of the DrawTarget that is passed to matter because it would seem
+  // logical to encoded its type in the recording, and on replaying the
+  // recording a DrawTarget of the same type would be created.  However, the
+  // passed DrawTarget's type doesn't seem to be encoded any more accurately
+  // than just "BackendType::CAIRO".  Even if it were, the code that replays the
+  // recording is PrintTranslator::TranslateRecording which (indirectly) calls
+  // MakePrintTarget on the type of nsIDeviceContextSpecProxy that is created
+  // for the platform that we're running on, and the type of DrawTarget that
+  // that returns is hardcoded.
+  //
+  // The only reason that we use cairo_recording_surface_create here is:
+  //
+  //   * It's pretty much the only cairo_*_surface_create methods that's both
+  //     available on all platforms and doesn't require allocating a
+  //     potentially large surface.
+  //
+  //   * Since we need a DrawTarget to pass to CreateRecordingDrawTarget we
+  //     might as well leverage our base class's machinery to create a
+  //     DrawTarget (it's as good a way as any other that will work), and to do
+  //     that we need a cairo_surface_t.
+  //
+  // So the fact that this is a "recording" PrintTarget and the function that
+  // we call here is cairo_recording_surface_create is simply a coincidence. We
+  // could use any cairo_*_surface_create method and this class would still
+  // work.
+  //
+  cairo_surface_t* surface =
+      cairo_recording_surface_create(CAIRO_CONTENT_COLOR_ALPHA, nullptr);
+
+  if (cairo_surface_status(surface)) {
+    return nullptr;
+  }
+
+  // The new object takes ownership of our surface reference.
+  RefPtr<PrintTargetRecording> target =
+      new PrintTargetRecording(surface, aSize);
+
+  return target.forget();
+}
+
+already_AddRefed<DrawTarget> PrintTargetRecording::MakeDrawTarget(
+    const IntSize& aSize, DrawEventRecorder* aRecorder) {
+  MOZ_ASSERT(aRecorder, "A DrawEventRecorder is required");
+
+  if (!aRecorder) {
+    return nullptr;
+  }
+
+  RefPtr<DrawTarget> dt = PrintTarget::MakeDrawTarget(aSize, nullptr);
+  if (dt) {
+    dt = CreateRecordingDrawTarget(aRecorder, dt);
+    if (!dt || !dt->IsValid()) {
+      return nullptr;
+    }
+  }
+
+  return dt.forget();
+}
+
+already_AddRefed<DrawTarget> PrintTargetRecording::CreateRecordingDrawTarget(
+    DrawEventRecorder* aRecorder, DrawTarget* aDrawTarget) {
+  MOZ_ASSERT(aRecorder);
+  MOZ_ASSERT(aDrawTarget);
+
+  RefPtr<DrawTarget> dt;
+
+  if (aRecorder) {
+    // It doesn't really matter what we pass as the DrawTarget here.
+    dt = gfx::Factory::CreateRecordingDrawTarget(aRecorder, aDrawTarget,
+                                                 aDrawTarget->GetRect());
+  }
+
+  if (!dt || !dt->IsValid()) {
+    gfxCriticalNote
+        << "Failed to create a recording DrawTarget for PrintTarget";
+    return nullptr;
+  }
+
+  return dt.forget();
+}
+
+}  // namespace gfx
+}  // namespace mozilla