From 2bf836ea939f08ca2b58d434af3a51f7ae48cc67 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Sun, 22 Apr 2007 21:18:20 +0000
Subject: [PATCH] From Michael Platings, "In the "new method" 3DS loader,
 inverse matrices were applied to vertices, but not normals, which caused some
 models to appear with normals doubly rotated. I've now added some code to
 transform the normals."

---
 src/osgPlugins/3ds/ReaderWriter3DS.cpp | 33 +++++++++++++++++---------
 1 file changed, 22 insertions(+), 11 deletions(-)

diff --git a/src/osgPlugins/3ds/ReaderWriter3DS.cpp b/src/osgPlugins/3ds/ReaderWriter3DS.cpp
index e9b8ced53..cd2d79b1a 100644
--- a/src/osgPlugins/3ds/ReaderWriter3DS.cpp
+++ b/src/osgPlugins/3ds/ReaderWriter3DS.cpp
@@ -229,6 +229,15 @@ void print(Lib3dsNode *node, int level) {
 
 }
 
+void copyLib3dsMatrixToOsgMatrix(osg::Matrix& osg_matrix, const Lib3dsMatrix lib3ds_matrix)
+{
+    osg_matrix.set(
+        lib3ds_matrix[0][0],lib3ds_matrix[0][1],lib3ds_matrix[0][2],lib3ds_matrix[0][3],
+        lib3ds_matrix[1][0],lib3ds_matrix[1][1],lib3ds_matrix[1][2],lib3ds_matrix[1][3],
+        lib3ds_matrix[2][0],lib3ds_matrix[2][1],lib3ds_matrix[2][2],lib3ds_matrix[2][3],
+        lib3ds_matrix[3][0],lib3ds_matrix[3][1],lib3ds_matrix[3][2],lib3ds_matrix[3][3]); 
+}
+
 // Transforms points by matrix if 'matrix' is not NULL
 // Creates a Geode and Geometry (as parent,child) and adds the Geode to 'parent' parameter iff 'parent' is non-NULL
 // Returns ptr to the Geode
@@ -368,11 +377,7 @@ osg::Node* ReaderWriter3DS::ReaderObject::processNode(StateSetMap drawStateMap,L
         if (pivoted) {
             // Transform object's pivot point to the world origin
             osg::MatrixTransform* T=new osg::MatrixTransform;
-            osgmatrix.set(
-                N[0][0],N[0][1],N[0][2],N[0][3],
-                N[1][0],N[1][1],N[1][2],N[1][3],
-                N[2][0],N[2][1],N[2][2],N[2][3],
-                N[3][0],N[3][1],N[3][2],N[3][3]); 
+            copyLib3dsMatrixToOsgMatrix(osgmatrix, N);
             T->setMatrix(osgmatrix);
             T->setName("3DSPIVOTPOINT: Translate pivotpoint to (world) origin");
             //cout<<"Translation for "<<node->name<<" is "<<osgmatrix<<endl;
@@ -380,11 +385,7 @@ osg::Node* ReaderWriter3DS::ReaderObject::processNode(StateSetMap drawStateMap,L
             // rotate about "origin" (after the transform this is the world origin)
             // BUG this matrix also contains the translation to the pivot point - we should plit that out (maybe)
             osg::MatrixTransform* R=new osg::MatrixTransform;
-            osgmatrix.set(
-                M[0][0],M[0][1],M[0][2],M[0][3],
-                M[1][0],M[1][1],M[1][2],M[1][3],
-                M[2][0],M[2][1],M[2][2],M[2][3],
-                M[3][0],M[3][1],M[3][2],M[3][3]); 
+            copyLib3dsMatrixToOsgMatrix(osgmatrix, M);
             R->setMatrix(osgmatrix);
             R->setName("3DSPIVOTPOINT: Rotate");
                 
@@ -504,7 +505,7 @@ osgDB::ReaderWriter::ReadResult ReaderWriter3DS::readNode(const std::string& fil
         }
     } 
 
-;    if (osg::getNotifyLevel()>=osg::INFO)
+    if (osg::getNotifyLevel()>=osg::INFO)
     {
         osg::notify(osg::NOTICE) << "Final OSG node structure looks like this:"<< endl;
         PrintVisitor pv(osg::notify(osg::NOTICE));
@@ -614,6 +615,16 @@ osg::Drawable*   ReaderWriter3DS::ReaderObject::createDrawable(Lib3dsMesh *m,Fac
 
         }
 
+        if (matrix)
+        {
+            osg::Matrix osg_matrix;
+            copyLib3dsMatrixToOsgMatrix(osg_matrix, *matrix);
+            for (i=0; i<noVertex; ++i)
+            {
+                (*osg_normals)[i] = osg::Matrix::transform3x3((*osg_normals)[i], osg_matrix);
+            }
+        }
+
         // normalize the normal list to unit length normals.
         for (i=0; i<noVertex; ++i)
         {