From d1f6169889914c169d0a3fc19f589d43231a3cc7 Mon Sep 17 00:00:00 2001
From: scrawl <scrawl@baseoftrash.de>
Date: Wed, 23 Mar 2016 16:48:41 +0100
Subject: [PATCH] Add special handling of RigGeometry tangents in ShaderVisitor

---
 components/sceneutil/riggeometry.cpp | 30 ++++++++++++++++++++++++++++
 components/sceneutil/riggeometry.hpp |  2 ++
 components/shader/shadervisitor.cpp  | 17 ++++++++++++----
 3 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/components/sceneutil/riggeometry.cpp b/components/sceneutil/riggeometry.cpp
index 87afce034..895ff7e34 100644
--- a/components/sceneutil/riggeometry.cpp
+++ b/components/sceneutil/riggeometry.cpp
@@ -99,6 +99,13 @@ void RigGeometry::setSourceGeometry(osg::ref_ptr<osg::Geometry> sourceGeometry)
     setColorArray(from.getColorArray());
     setSecondaryColorArray(from.getSecondaryColorArray());
     setFogCoordArray(from.getFogCoordArray());
+
+    // need to copy over texcoord list manually due to a missing null pointer check in setTexCoordArrayList(), this has been fixed in OSG 3.5
+    osg::Geometry::ArrayList& texCoordList = from.getTexCoordArrayList();
+    for (unsigned int i=0; i<texCoordList.size(); ++i)
+        if (texCoordList[i])
+            setTexCoordArray(i, texCoordList[i], osg::Array::BIND_PER_VERTEX);
+
     setTexCoordArrayList(from.getTexCoordArrayList());
     setVertexAttribArrayList(from.getVertexAttribArrayList());
 
@@ -120,6 +127,19 @@ void RigGeometry::setSourceGeometry(osg::ref_ptr<osg::Geometry> sourceGeometry)
         normalArray->setVertexBufferObject(vbo);
         setNormalArray(normalArray, osg::Array::BIND_PER_VERTEX);
     }
+
+    if (from.getTexCoordArray(7) && dynamic_cast<osg::Vec4Array*>(from.getTexCoordArray(7)))
+    {
+        // tangents
+        osg::ref_ptr<osg::Array> tangentArray = osg::clone(from.getTexCoordArray(7), osg::CopyOp::DEEP_COPY_ALL);
+        tangentArray->setVertexBufferObject(vbo);
+        setTexCoordArray(7, tangentArray, osg::Array::BIND_PER_VERTEX);
+    }
+}
+
+osg::ref_ptr<osg::Geometry> RigGeometry::getSourceGeometry()
+{
+    return mSourceGeometry;
 }
 
 bool RigGeometry::initFromParentSkeleton(osg::NodeVisitor* nv)
@@ -225,9 +245,11 @@ void RigGeometry::update(osg::NodeVisitor* nv)
     // skinning
     osg::Vec3Array* positionSrc = static_cast<osg::Vec3Array*>(mSourceGeometry->getVertexArray());
     osg::Vec3Array* normalSrc = static_cast<osg::Vec3Array*>(mSourceGeometry->getNormalArray());
+    osg::Vec4Array* tangentSrc = static_cast<osg::Vec4Array*>(mSourceGeometry->getTexCoordArray(7));
 
     osg::Vec3Array* positionDst = static_cast<osg::Vec3Array*>(getVertexArray());
     osg::Vec3Array* normalDst = static_cast<osg::Vec3Array*>(getNormalArray());
+    osg::Vec4Array* tangentDst = static_cast<osg::Vec4Array*>(getTexCoordArray(7));
 
     for (Bone2VertexMap::const_iterator it = mBone2VertexMap.begin(); it != mBone2VertexMap.end(); ++it)
     {
@@ -251,11 +273,19 @@ void RigGeometry::update(osg::NodeVisitor* nv)
             unsigned short vertex = *vertexIt;
             (*positionDst)[vertex] = resultMat.preMult((*positionSrc)[vertex]);
             (*normalDst)[vertex] = osg::Matrix::transform3x3((*normalSrc)[vertex], resultMat);
+            if (tangentDst)
+            {
+                osg::Vec4f srcTangent = (*tangentSrc)[vertex];
+                osg::Vec3f transformedTangent = osg::Matrix::transform3x3(osg::Vec3f(srcTangent.x(), srcTangent.y(), srcTangent.z()), resultMat);
+                (*tangentDst)[vertex] = osg::Vec4f(transformedTangent, srcTangent.w());
+            }
         }
     }
 
     positionDst->dirty();
     normalDst->dirty();
+    if (tangentDst)
+        tangentDst->dirty();
 }
 
 void RigGeometry::updateBounds(osg::NodeVisitor *nv)
diff --git a/components/sceneutil/riggeometry.hpp b/components/sceneutil/riggeometry.hpp
index 90d4c1156..8ce753402 100644
--- a/components/sceneutil/riggeometry.hpp
+++ b/components/sceneutil/riggeometry.hpp
@@ -43,6 +43,8 @@ namespace SceneUtil
         /// @note The source geometry will not be modified.
         void setSourceGeometry(osg::ref_ptr<osg::Geometry> sourceGeom);
 
+        osg::ref_ptr<osg::Geometry> getSourceGeometry();
+
         // Called automatically by our CullCallback
         void update(osg::NodeVisitor* nv);
 
diff --git a/components/shader/shadervisitor.cpp b/components/shader/shadervisitor.cpp
index ea9cb11ac..dbba721c2 100644
--- a/components/shader/shadervisitor.cpp
+++ b/components/shader/shadervisitor.cpp
@@ -14,6 +14,7 @@
 
 #include <components/resource/imagemanager.hpp>
 #include <components/vfs/manager.hpp>
+#include <components/sceneutil/riggeometry.hpp>
 
 #include "shadermanager.hpp"
 
@@ -313,24 +314,32 @@ namespace Shader
         {
             const ShaderRequirements& reqs = mRequirements.back();
 
+            osg::ref_ptr<osg::Geometry> sourceGeometry = &geometry;
+            SceneUtil::RigGeometry* rig = dynamic_cast<SceneUtil::RigGeometry*>(&geometry);
+            if (rig)
+                sourceGeometry = rig->getSourceGeometry();
+
             if (mAllowedToModifyStateSets)
             {
                 // make sure that all UV sets are there
                 for (std::map<int, std::string>::const_iterator it = reqs.mTextures.begin(); it != reqs.mTextures.end(); ++it)
                 {
-                    if (geometry.getTexCoordArray(it->first) == NULL)
-                        geometry.setTexCoordArray(it->first, geometry.getTexCoordArray(0));
+                    if (sourceGeometry->getTexCoordArray(it->first) == NULL)
+                        sourceGeometry->setTexCoordArray(it->first, sourceGeometry->getTexCoordArray(0));
                 }
             }
 
             if (reqs.mTexStageRequiringTangents != -1 && mAllowedToModifyStateSets)
             {
                 osg::ref_ptr<osgUtil::TangentSpaceGenerator> generator (new osgUtil::TangentSpaceGenerator);
-                generator->generate(&geometry, reqs.mTexStageRequiringTangents);
+                generator->generate(sourceGeometry, reqs.mTexStageRequiringTangents);
 
-                geometry.setTexCoordArray(7, generator->getTangentArray(), osg::Array::BIND_PER_VERTEX);
+                sourceGeometry->setTexCoordArray(7, generator->getTangentArray(), osg::Array::BIND_PER_VERTEX);
             }
 
+            if (rig)
+                rig->setSourceGeometry(sourceGeometry);
+
             // TODO: find a better place for the stateset
             if (reqs.mShaderRequired || mForceShaders)
                 createProgram(reqs, geometry);