From bbb7da03ac56a600b72dd81708db3f2af2113887 Mon Sep 17 00:00:00 2001
From: Emmanuele Bassi <ebassi@linux.intel.com>
Date: Mon, 13 Feb 2012 18:19:48 +0000
Subject: [PATCH] Add a note on the paint volume origin
This should avoid trying to fix the origin of a paint volume set from
the allocation's origin, and thus breaking everything.
A PaintVolume for an actor is defined to be relative to the actor's
modelview unless specifically modified by internal functions; the origin
of an actor's allocation is, on the other hand, parent-relative.
---
clutter/clutter-actor.c | 5 ++++-
clutter/clutter-paint-volume.c | 8 ++++++--
clutter/clutter-types.h | 5 ++++-
3 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/clutter/clutter-actor.c b/clutter/clutter-actor.c
index 61ec21980..3bb8b96f6 100644
--- a/clutter/clutter-actor.c
+++ b/clutter/clutter-actor.c
@@ -4692,7 +4692,10 @@ clutter_actor_real_get_paint_volume (ClutterActor *self,
res = FALSE;
/* we start from the allocation */
- clutter_paint_volume_set_from_allocation (volume, self);
+ clutter_paint_volume_set_width (volume,
+ priv->allocation.x2 - priv->allocation.x1);
+ clutter_paint_volume_set_height (volume,
+ priv->allocation.y2 - priv->allocation.y1);
/* if the actor has a clip set then we have a pretty definite
* size for the paint volume: the actor cannot possibly paint
diff --git a/clutter/clutter-paint-volume.c b/clutter/clutter-paint-volume.c
index 5b5427460..419b28198 100644
--- a/clutter/clutter-paint-volume.c
+++ b/clutter/clutter-paint-volume.c
@@ -970,6 +970,10 @@ _clutter_actor_set_default_paint_volume (ClutterActor *self,
clutter_actor_get_allocation_box (self, &box);
+ /* we only set the width and height, as the paint volume is defined
+ * to be relative to the actor's modelview, which means that the
+ * allocation's origin has already been applied
+ */
clutter_paint_volume_set_width (volume, box.x2 - box.x1);
clutter_paint_volume_set_height (volume, box.y2 - box.y1);
@@ -984,8 +988,8 @@ _clutter_actor_set_default_paint_volume (ClutterActor *self,
* Sets the #ClutterPaintVolume from the allocation of @actor.
*
* This function should be used when overriding the
- * <function>get_paint_volume()</function> by #ClutterActor sub-classes that do
- * not paint outside their allocation.
+ * #ClutterActorClass.get_paint_volume() by #ClutterActor sub-classes
+ * that do not paint outside their allocation.
*
* A typical example is:
*
diff --git a/clutter/clutter-types.h b/clutter/clutter-types.h
index 2136874ee..ecd0d161f 100644
--- a/clutter/clutter-types.h
+++ b/clutter/clutter-types.h
@@ -112,9 +112,12 @@ typedef union _ClutterEvent ClutterEvent;
* whose members cannot be directly accessed.
*
* A <structname>ClutterPaintVolume</structname> represents an
- * a bounding volume whos internal representation isn't defined but
+ * a bounding volume whose internal representation isn't defined but
* can be set and queried in terms of an axis aligned bounding box.
*
+ * A <structname>ClutterPaintVolume</structname> for a #ClutterActor
+ * is defined to be relative from the current actor modelview matrix.
+ *
* Other internal representation and methods for describing the
* bounding volume may be added in the future.
*