From 36b5e5901950c95230dfd6c6e44559ca5238906c Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Fri, 27 Nov 2009 15:32:43 +0000
Subject: [PATCH] From Paul Martz, "This change address the following issue: an
 app opens a Viewer on a multidisplay system, configured to
 setUpViewAcrossAllDisplays, with a non-default clear mask. In this case, OSG
 failed to propagate the clear mask to the slave Cameras, resulting in the
 clear mask being ignored. To fix this issue, this revision adds a new
 CullSettings::VariablesMask bit, CLEAR_MASK, to explicitly control
 inheritance of the clear mask. This bit is set by default, which means that
 the clear mask now inherits by default, whereas previously it did not."

---
 include/osg/Camera          |  2 +-
 include/osg/CullSettings    | 37 +++++++++++++++++++------------------
 src/osg/Camera.cpp          |  3 +++
 src/osgUtil/CullVisitor.cpp |  8 ++++++++
 4 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/include/osg/Camera b/include/osg/Camera
index b1d5b538f..5c733e2b8 100644
--- a/include/osg/Camera
+++ b/include/osg/Camera
@@ -84,7 +84,7 @@ class OSG_EXPORT Camera : public Transform, public CullSettings
 
         /** Set the clear mask used in glClear(..).
           * Defaults to GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT. */
-        inline void setClearMask(GLbitfield mask) { _clearMask = mask; }
+        inline void setClearMask(GLbitfield mask) { _clearMask = mask; applyMaskAction(CLEAR_MASK); }
 
         /** Get the clear mask.*/
         inline GLbitfield getClearMask() const { return _clearMask; }
diff --git a/include/osg/CullSettings b/include/osg/CullSettings
index 617f7251a..b0da3ad57 100644
--- a/include/osg/CullSettings
+++ b/include/osg/CullSettings
@@ -58,24 +58,25 @@ class OSG_EXPORT CullSettings
         
         enum VariablesMask
         {
-            COMPUTE_NEAR_FAR_MODE                   = 0x00000001,
-            CULLING_MODE                            = 0x00000002,
-            LOD_SCALE                               = 0x00000004,
-            SMALL_FEATURE_CULLING_PIXEL_SIZE        = 0x00000008,
-            CLAMP_PROJECTION_MATRIX_CALLBACK        = 0x00000010,
-            NEAR_FAR_RATIO                          = 0x00000020,
-            IMPOSTOR_ACTIVE                         = 0x00000040,
-            DEPTH_SORT_IMPOSTOR_SPRITES             = 0x00000080,
-            IMPOSTOR_PIXEL_ERROR_THRESHOLD          = 0x00000100,
-            NUM_FRAMES_TO_KEEP_IMPOSTORS_SPRITES    = 0x00000200,
-            CULL_MASK                               = 0x00000400,
-            CULL_MASK_LEFT                          = 0x00000800,
-            CULL_MASK_RIGHT                         = 0x00001000,
-            CLEAR_COLOR                             = 0x00002000,
-            LIGHTING_MODE                           = 0x00004000,
-            LIGHT                                   = 0x00008000,
-            DRAW_BUFFER                             = 0x00010000,
-            READ_BUFFER                             = 0x00020000,
+            COMPUTE_NEAR_FAR_MODE                   = (0x1 << 0),
+            CULLING_MODE                            = (0x1 << 1),
+            LOD_SCALE                               = (0x1 << 2),
+            SMALL_FEATURE_CULLING_PIXEL_SIZE        = (0x1 << 3),
+            CLAMP_PROJECTION_MATRIX_CALLBACK        = (0x1 << 4),
+            NEAR_FAR_RATIO                          = (0x1 << 5),
+            IMPOSTOR_ACTIVE                         = (0x1 << 6),
+            DEPTH_SORT_IMPOSTOR_SPRITES             = (0x1 << 7),
+            IMPOSTOR_PIXEL_ERROR_THRESHOLD          = (0x1 << 8),
+            NUM_FRAMES_TO_KEEP_IMPOSTORS_SPRITES    = (0x1 << 9),
+            CULL_MASK                               = (0x1 << 10),
+            CULL_MASK_LEFT                          = (0x1 << 11),
+            CULL_MASK_RIGHT                         = (0x1 << 12),
+            CLEAR_COLOR                             = (0x1 << 13),
+            CLEAR_MASK                              = (0x1 << 14),
+            LIGHTING_MODE                           = (0x1 << 15),
+            LIGHT                                   = (0x1 << 16),
+            DRAW_BUFFER                             = (0x1 << 17),
+            READ_BUFFER                             = (0x1 << 18),
 
             NO_VARIABLES                            = 0x00000000,
             ALL_VARIABLES                           = 0xFFFFFFFF
diff --git a/src/osg/Camera.cpp b/src/osg/Camera.cpp
index 487fb1256..94c74d0a2 100644
--- a/src/osg/Camera.cpp
+++ b/src/osg/Camera.cpp
@@ -397,6 +397,9 @@ void Camera::inheritCullSettings(const CullSettings& settings, unsigned int inhe
         if (inheritanceMask & CLEAR_COLOR)
             _clearColor = camera->_clearColor;
 
+        if (inheritanceMask & CLEAR_MASK)
+            _clearMask = camera->_clearMask;
+
         if (inheritanceMask & DRAW_BUFFER)
             _drawBuffer = camera->_drawBuffer;
 
diff --git a/src/osgUtil/CullVisitor.cpp b/src/osgUtil/CullVisitor.cpp
index 5d5c891c4..2b5870c5e 100644
--- a/src/osgUtil/CullVisitor.cpp
+++ b/src/osgUtil/CullVisitor.cpp
@@ -1304,6 +1304,14 @@ void CullVisitor::apply(osg::Camera& camera)
         {
             rtts->setClearColor(camera.getClearColor());
         }
+        if (camera.getInheritanceMask() & CLEAR_MASK)
+        {
+            rtts->setClearMask(previous_stage->getClearMask());
+        }
+        else
+        {
+            rtts->setClearMask(camera.getClearMask());
+        }
 
         
         // set the color mask.