From 656a1b6da50703c8b41230f1e471f1bf5ed8a8f6 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Tue, 1 Jun 2010 14:12:03 +0000
Subject: [PATCH] From Frederic Bouvier, "here is my proposal. It is supposed
 to be used like this :

   osg::Camera* c = createCamera();
   c->attach( osg::Camera::COLOR_BUFFER0, texture3d, 0,
osg::Camera::FACE_CONTROLLED_BY_GEOMETRY_SHADER );

it works also for cubemap textures and 2d texture arrays
"
---
 include/osg/Camera            |  2 ++
 include/osg/FrameBufferObject |  2 ++
 src/osg/Camera.cpp            |  2 ++
 src/osg/FrameBufferObject.cpp | 18 +++++++++++++++---
 4 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/include/osg/Camera b/include/osg/Camera
index d2ae3a50f..5eb3dc216 100644
--- a/include/osg/Camera
+++ b/include/osg/Camera
@@ -330,6 +330,8 @@ class OSG_EXPORT Camera : public Transform, public CullSettings
             COLOR_BUFFER15 = COLOR_BUFFER0+15
         };
 
+        static const unsigned int FACE_CONTROLLED_BY_GEOMETRY_SHADER;
+
         /** Attach a buffer with specified OpenGL internal format.*/
         void attach(BufferComponent buffer, GLenum internalFormat);
 
diff --git a/include/osg/FrameBufferObject b/include/osg/FrameBufferObject
index 3a84c4a29..4401450b1 100644
--- a/include/osg/FrameBufferObject
+++ b/include/osg/FrameBufferObject
@@ -157,6 +157,7 @@ namespace osg
         typedef void GL_APIENTRY TglFramebufferTexture1D(GLenum, GLenum, GLenum, GLuint, GLint);
         typedef void GL_APIENTRY TglFramebufferTexture2D(GLenum, GLenum, GLenum, GLuint, GLint);
         typedef void GL_APIENTRY TglFramebufferTexture3D(GLenum, GLenum, GLenum, GLuint, GLint, GLint);
+        typedef void GL_APIENTRY TglFramebufferTexture(GLenum, GLenum, GLint, GLint);
         typedef void GL_APIENTRY TglFramebufferTextureLayer(GLenum, GLenum, GLuint, GLint, GLint);
         typedef void GL_APIENTRY TglFramebufferRenderbuffer(GLenum, GLenum, GLenum, GLuint);
         typedef void GL_APIENTRY TglGenerateMipmap(GLenum);
@@ -176,6 +177,7 @@ namespace osg
         TglFramebufferTexture1D* glFramebufferTexture1D;
         TglFramebufferTexture2D* glFramebufferTexture2D;
         TglFramebufferTexture3D* glFramebufferTexture3D;
+        TglFramebufferTexture* glFramebufferTexture;
         TglFramebufferTextureLayer* glFramebufferTextureLayer;
         TglFramebufferRenderbuffer* glFramebufferRenderbuffer;
         TglGenerateMipmap* glGenerateMipmap;
diff --git a/src/osg/Camera.cpp b/src/osg/Camera.cpp
index 3b3584e1b..ccef7f8bd 100644
--- a/src/osg/Camera.cpp
+++ b/src/osg/Camera.cpp
@@ -16,6 +16,8 @@
 
 using namespace osg;
 
+const unsigned int Camera::FACE_CONTROLLED_BY_GEOMETRY_SHADER = 0xffffffff;
+
 Camera::Camera():
     _view(0),
     _allowEventFocus(true),
diff --git a/src/osg/FrameBufferObject.cpp b/src/osg/FrameBufferObject.cpp
index cb23a82f5..ce94c3014 100644
--- a/src/osg/FrameBufferObject.cpp
+++ b/src/osg/FrameBufferObject.cpp
@@ -55,6 +55,7 @@ FBOExtensions::FBOExtensions(unsigned int contextID)
     glFramebufferTexture1D(0),
     glFramebufferTexture2D(0),
     glFramebufferTexture3D(0),
+    glFramebufferTexture(0),
     glFramebufferTextureLayer(0),
     glFramebufferRenderbuffer(0),
     glGenerateMipmap(0),
@@ -73,6 +74,7 @@ FBOExtensions::FBOExtensions(unsigned int contextID)
     LOAD_FBO_EXT(glFramebufferTexture1D);
     LOAD_FBO_EXT(glFramebufferTexture2D);
     LOAD_FBO_EXT(glFramebufferTexture3D);
+    LOAD_FBO_EXT(glFramebufferTexture);
     LOAD_FBO_EXT(glFramebufferTextureLayer);
     LOAD_FBO_EXT(glFramebufferRenderbuffer);
     LOAD_FBO_EXT(glGenerateMipmap);
@@ -90,6 +92,7 @@ FBOExtensions::FBOExtensions(unsigned int contextID)
         glFramebufferTexture1D != 0 &&
         glFramebufferTexture2D != 0 &&
         glFramebufferTexture3D != 0 &&
+        glFramebufferTexture != 0 &&
         glFramebufferRenderbuffer != 0 &&
         glGenerateMipmap != 0 &&
         glGetRenderbufferParameteriv != 0;
@@ -554,16 +557,25 @@ void FrameBufferAttachment::attach(State &state, GLenum target, GLenum attachmen
         ext->glFramebufferTexture2D(target, attachment_point, GL_TEXTURE_2D_MULTISAMPLE, tobj->id(), _ximpl->level);
         break;
     case Pimpl::TEXTURE3D:
-        ext->glFramebufferTexture3D(target, attachment_point, GL_TEXTURE_3D, tobj->id(), _ximpl->level, _ximpl->zoffset);
+        if (_ximpl->zoffset == Camera::FACE_CONTROLLED_BY_GEOMETRY_SHADER)
+            ext->glFramebufferTexture(target, attachment_point, tobj->id(), _ximpl->level);
+        else
+            ext->glFramebufferTexture3D(target, attachment_point, GL_TEXTURE_3D, tobj->id(), _ximpl->level, _ximpl->zoffset);
         break;
     case Pimpl::TEXTURE2DARRAY:
-        ext->glFramebufferTextureLayer(target, attachment_point, tobj->id(), _ximpl->level, _ximpl->zoffset);
+        if (_ximpl->zoffset == Camera::FACE_CONTROLLED_BY_GEOMETRY_SHADER)
+            ext->glFramebufferTexture(target, attachment_point, tobj->id(), _ximpl->level);
+        else
+            ext->glFramebufferTextureLayer(target, attachment_point, tobj->id(), _ximpl->level, _ximpl->zoffset);
         break;
     case Pimpl::TEXTURERECT:
         ext->glFramebufferTexture2D(target, attachment_point, GL_TEXTURE_RECTANGLE, tobj->id(), 0);
         break;
     case Pimpl::TEXTURECUBE:
-        ext->glFramebufferTexture2D(target, attachment_point, GL_TEXTURE_CUBE_MAP_POSITIVE_X + _ximpl->cubeMapFace, tobj->id(), _ximpl->level);
+        if (_ximpl->cubeMapFace == Camera::FACE_CONTROLLED_BY_GEOMETRY_SHADER)
+            ext->glFramebufferTexture(target, attachment_point, tobj->id(), _ximpl->level);
+        else
+            ext->glFramebufferTexture2D(target, attachment_point, GL_TEXTURE_CUBE_MAP_POSITIVE_X + _ximpl->cubeMapFace, tobj->id(), _ximpl->level);
         break;
     }
 }