Bug 907011 - Expose cairo objects from gfxContext when using Azure/cairo. r=Bas

gfx/2d/DrawTargetCairo.cpp

@@ -1026,6 +1026,9 @@ DrawTargetCairo::GetNativeSurface(NativeSurfaceType aType)
   if (aType == NATIVE_SURFACE_CAIRO_SURFACE) {
     return cairo_get_target(mContext);
   }
+  if (aType == NATIVE_SURFACE_CAIRO_CONTEXT) {
+    return mContext;
+  }
 
   return nullptr;
 }

gfx/2d/Types.h

@@ -69,6 +69,7 @@ enum NativeSurfaceType
 {
   NATIVE_SURFACE_D3D10_TEXTURE,
   NATIVE_SURFACE_CAIRO_SURFACE,
+  NATIVE_SURFACE_CAIRO_CONTEXT,
   NATIVE_SURFACE_CGCONTEXT,
   NATIVE_SURFACE_CGCONTEXT_ACCELERATED
 };

gfx/thebes/gfxContext.cpp

@@ -138,7 +138,19 @@ gfxContext::~gfxContext()
 gfxASurface *
 gfxContext::OriginalSurface()
 {
-    return mSurface;
+    if (mCairo || mSurface) {
+        return mSurface;
+    }
+
+    if (mOriginalDT && mOriginalDT->GetType() == BACKEND_CAIRO) {
+        cairo_surface_t *s =
+            (cairo_surface_t*)mOriginalDT->GetNativeSurface(NATIVE_SURFACE_CAIRO_SURFACE);
+        if (s) {
+            mSurface = gfxASurface::Wrap(s);
+            return mSurface;
+        }
+    }
+    return nullptr;
 }
 
 already_AddRefed<gfxASurface>
@@ -157,6 +169,16 @@ gfxContext::CurrentSurface(gfxFloat *dx, gfxFloat *dy)
         cairo_surface_get_device_offset(s, dx, dy);
     return gfxASurface::Wrap(s);
   } else {
+    if (mDT->GetType() == BACKEND_CAIRO) {
+        cairo_surface_t *s =
+            (cairo_surface_t*)mDT->GetNativeSurface(NATIVE_SURFACE_CAIRO_SURFACE);
+        if (s) {
+            if (dx && dy)
+                cairo_surface_get_device_offset(s, dx, dy);
+            return gfxASurface::Wrap(s);
+        }
+    }
+
     if (dx && dy) {
       *dx = *dy = 0;
     }
@@ -172,6 +194,14 @@ gfxContext::GetCairo()
     return mCairo;
   }
 
+  if (mDT->GetType() == BACKEND_CAIRO) {
+    cairo_t *ctx =
+      (cairo_t*)mOriginalDT->GetNativeSurface(NATIVE_SURFACE_CAIRO_CONTEXT);
+    if (ctx) {
+      return ctx;
+    }
+  }
+
   if (mRefCairo) {
     // Set transform!
     return mRefCairo;

gfx/thebes/gfxWindowsNativeDrawing.cpp

@@ -11,6 +11,7 @@
 #include "gfxWindowsSurface.h"
 #include "gfxAlphaRecovery.h"
 #include "gfxPattern.h"
+#include "mozilla/gfx/2D.h"
 
 enum {
     RENDER_STATE_INIT,
@@ -182,7 +183,9 @@ gfxWindowsNativeDrawing::BeginNativeDrawing()
 bool
 gfxWindowsNativeDrawing::IsDoublePass()
 {
-    if (!mContext->IsCairo()) {
+    if (!mContext->IsCairo() &&
+        (mContext->GetDrawTarget()->GetType() != mozilla::gfx::BACKEND_CAIRO ||
+         mContext->GetDrawTarget()->IsDualDrawTarget())) {
       return true;
     }