Bug 477708 - expose nsIRegion::getrects() to scripts r=vlad

gfx/idl/nsIScriptableRegion.idl

@@ -46,7 +46,7 @@ class nsIRegion;
 [ptr] native nsIRegion(nsIRegion);
 
 
-[scriptable, uuid(82d8f400-5bde-11d3-b033-b27a62766bbc)]
+[scriptable, uuid(4d179656-a5bd-42a6-a937-c81f820dcf2f)]
 interface nsIScriptableRegion : nsISupports
 {
   void init ( ) ;
@@ -187,6 +187,13 @@ interface nsIScriptableRegion : nsISupports
   **/
   void offset ( in long aXOffset, in long aYOffset ) ;
 
+  /**
+   * @return null if there are no rects,
+   * @return flat array of rects,ie [x1,y1,width1,height1,x2...].
+   * The result will contain bogus data if values don't fit in 31 bit
+   **/
+  void getRects();
+
   /**
   * does the region intersect the rectangle?
   *

gfx/src/Makefile.in

@@ -55,6 +55,8 @@ REQUIRES	= xpcom \
 		  view \
 		  unicharutil \
 		  thebes \
+		  js \
+		  xpconnect \
 		  $(NULL)
 
 DIRS        = shared thebes

gfx/src/nsScriptableRegion.cpp

@@ -22,6 +22,7 @@
  *
  * Contributor(s):
  *   Patrick Beard
+ *   Taras Glek
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either of the GNU General Public License Version 2 or later (the "GPL"),
@@ -38,10 +39,12 @@
  * ***** END LICENSE BLOCK ***** */
 
 #include "nsScriptableRegion.h"
-#include "nsIRegion.h"
 #include "nsCOMPtr.h"
+#include "nsIXPConnect.h"
+#include "nsServiceManagerUtils.h"
+#include "jsapi.h"
 
-nsScriptableRegion::nsScriptableRegion(nsIRegion* region) : mRegion(nsnull)
+nsScriptableRegion::nsScriptableRegion(nsIRegion* region) : mRegion(nsnull), mRectSet(nsnull)
 {
 	mRegion = region;
 	NS_IF_ADDREF(mRegion);
@@ -49,7 +52,10 @@ nsScriptableRegion::nsScriptableRegion(nsIRegion* region) : mRegion(nsnull)
 
 nsScriptableRegion::~nsScriptableRegion()
 {
-	NS_IF_RELEASE(mRegion);
+  if (mRegion) {
+    mRegion->FreeRects(mRectSet);
+    NS_RELEASE(mRegion);
+  }
 }
 
 NS_IMPL_ISUPPORTS1(nsScriptableRegion, nsIScriptableRegion)
@@ -149,3 +155,50 @@ NS_IMETHODIMP nsScriptableRegion::GetRegion(nsIRegion** outRgn)
   NS_IF_ADDREF(*outRgn);
   return NS_OK;
 }
+
+NS_IMETHODIMP nsScriptableRegion::GetRects() {
+  nsAXPCNativeCallContext *ncc = nsnull;
+  nsIXPConnect *xpConnect;
+  nsresult rv = CallGetService(nsIXPConnect::GetCID(), &xpConnect);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = xpConnect->GetCurrentNativeCallContext(&ncc);
+  NS_ENSURE_SUCCESS(rv, rv);
+  
+  if (!ncc)
+    return NS_ERROR_FAILURE;
+  
+  jsval *retvalPtr;
+  ncc->GetRetValPtr(&retvalPtr);
+  
+  rv = mRegion->GetRects(&mRectSet);
+  NS_ENSURE_SUCCESS(rv, rv);
+  
+  if (!mRectSet->mNumRects) {
+    *retvalPtr = JSVAL_NULL;
+    ncc->SetReturnValueWasSet(PR_TRUE);
+    return NS_OK;
+  }
+
+  JSContext *cx = nsnull;
+  
+  rv = ncc->GetJSContext(&cx);
+  NS_ENSURE_SUCCESS(rv, rv);
+  
+  JSObject *destArray = JS_NewArrayObject(cx, mRectSet->mNumRects*4, NULL);
+  *retvalPtr = OBJECT_TO_JSVAL(destArray);
+  ncc->SetReturnValueWasSet(PR_TRUE);
+  
+  for(PRUint32 i = 0; i < mRectSet->mNumRects; i++) {
+    nsRegionRect &rect = mRectSet->mRects[i];
+    int n = i*4;
+    // This will contain bogus data if values don't fit in 31 bit
+    JS_DefineElement(cx, destArray, n, INT_TO_JSVAL(rect.x), NULL, NULL, JSPROP_ENUMERATE);
+    JS_DefineElement(cx, destArray, n+1, INT_TO_JSVAL(rect.y), NULL, NULL, JSPROP_ENUMERATE);
+    JS_DefineElement(cx, destArray, n+2, INT_TO_JSVAL(rect.width), NULL, NULL, JSPROP_ENUMERATE);
+    JS_DefineElement(cx, destArray, n+3, INT_TO_JSVAL(rect.height), NULL, NULL, JSPROP_ENUMERATE);
+  }
+
+  NS_ENSURE_SUCCESS(rv, rv);
+  return NS_OK;
+}

gfx/src/nsScriptableRegion.h

@@ -39,6 +39,7 @@
 
 #include "nsIScriptableRegion.h"
 #include "gfxCore.h"
+#include "nsIRegion.h"
 
 class nsIRegion;
 
@@ -56,4 +57,5 @@ public:
 
 private:
 	nsIRegion* mRegion;
+	nsRegionRectSet *mRectSet;
 };