Merge lp:~smspillaz/compiz-core/compiz-core.fix_978900 into lp:compiz-core

[Sam Spilsbury]

== Problem ==

It was possible that the requested paint region would never intersect the allowed region for shadows so windows would always be painted with full shadows. (eg, shadowRegion is a region with a big hole in the middle, and requested paints fell within that hole)

== Solution ==

Intersect against the full output region when checking whether to use the offset region provided.

== Tests ==

already covered.

[Alan Griffiths (alan-griffiths)]

LGTM

review: Approve

[Daniel van Vugt (vanvugt)]

I don't see any change with this branch. At least there are no regressions.

On both the machines I tested, dropdown menu shadows are never clipped at all (bug 659816). So I can't tell if this fix is working.

review: Abstain

[Daniel van Vugt (vanvugt)]

Hmm, my precise test machine is now behaving better than it was yesterday. I'll retest this...

[Daniel van Vugt (vanvugt)]

Now tested on precise. Sad to say that bug 978900 is not fixed. :(

review: Needs Fixing

[Daniel van Vugt (vanvugt)]

Actually it seems I made a mistake in my debian/patches/series. This fix is now working on precise.

review: Approve

=== modified file 'plugins/decor/src/decor.cpp'
--- plugins/decor/src/decor.cpp	2012-04-08 10:09:51 +0000
+++ plugins/decor/src/decor.cpp	2012-04-11 13:23:43 +0000
@@ -214,26 +214,6 @@
 		         const CompRegion   &region,
 		         unsigned int       mask)
 {
-    const CompRegion *preg = NULL;
-
-    if ((mask & (PAINT_WINDOW_ON_TRANSFORMED_SCREEN_MASK |
-		 PAINT_WINDOW_WITH_OFFSET_MASK)))
-	preg = &region;
-    else if (mask & PAINT_WINDOW_TRANSFORMED_MASK)
-	preg = &infiniteRegion;
-    else
-    {
-	tmpRegion = shadowRegion;
-	tmpRegion &= region;
-	preg = &tmpRegion;
-    }
-
-    /* In case some plugin needs to paint us with an offset region */
-    if (preg->isEmpty ())
-	preg = &region;
-
-    const CompRegion &reg (*preg);
-
     if (wd &&
 	wd->decor->type == WINDOW_DECORATION_TYPE_PIXMAP)
     {
@@ -241,6 +221,30 @@
 	GLTexture::MatrixList ml (1);
 	mask |= PAINT_WINDOW_BLEND_MASK;
 
+	const CompRegion *preg = NULL;
+
+	if ((mask & (PAINT_WINDOW_ON_TRANSFORMED_SCREEN_MASK |
+		 PAINT_WINDOW_WITH_OFFSET_MASK)))
+	    preg = &region;
+	else if (mask & PAINT_WINDOW_TRANSFORMED_MASK)
+	    preg = &infiniteRegion;
+	else
+	{
+	    tmpRegion = mOutputRegion;
+	    tmpRegion &= region;
+
+	    if (tmpRegion.isEmpty ())
+		preg = &region;
+	    else
+		preg = &shadowRegion;
+	}
+
+	/* In case some plugin needs to paint us with an offset region */
+	if (preg->isEmpty ())
+	    preg = &region;
+
+	const CompRegion &reg (*preg);
+
 	gWindow->geometry ().reset ();
 
 	for (int i = 0; i < wd->nQuad; i++)
@@ -262,8 +266,7 @@
 	    gWindow->glDrawTexture (wd->decor->texture->textures[0],
 				    attrib, mask);
     }
-    else if (wd && !reg.isEmpty () &&
-	     wd->decor->type == WINDOW_DECORATION_TYPE_WINDOW)
+    else if (wd && wd->decor->type == WINDOW_DECORATION_TYPE_WINDOW)
     {
 	GLTexture::MatrixList ml (1);
 
@@ -276,7 +279,7 @@
 	{
 	    ml[0] = gWindow->matrices ()[0];
 	    gWindow->geometry ().reset ();
-	    gWindow->glAddGeometry (ml, window->frameRegion (), reg);
+	    gWindow->glAddGeometry (ml, window->frameRegion (), region);
 
 	    if (gWindow->geometry ().vCount)
 		gWindow->glDrawTexture (gWindow->textures ()[0], attrib, mask);
@@ -289,7 +292,7 @@
 	    {
 		ml[0] = gWindow->matrices ()[i];
 		gWindow->geometry ().reset ();
-		gWindow->glAddGeometry (ml, regions[i], reg);
+		gWindow->glAddGeometry (ml, regions[i], region);
 
 		if (gWindow->geometry ().vCount)
 		    gWindow->glDrawTexture (gWindow->textures ()[i], attrib,