diff -ru trackballs-1.1.4.orig/src/glHelp.cc trackballs-1.1.4/src/glHelp.cc
--- trackballs-1.1.4.orig/src/glHelp.cc	2007-04-07 09:15:09.000000000 -0400
+++ trackballs-1.1.4/src/glHelp.cc	2011-04-12 12:04:01.142847026 -0400
@@ -741,29 +741,6 @@
     }
 }
 
-/* C <- A(B) */
-void useMatrix(Matrix4d A,const double B[3],double C[3]) {
-  int i,k;
-  for(i=0;i<3;i++) {
-    C[i] = A[i][3];
-    for(k=0;k<3;k++)
-      C[i] += A[i][k] * B[k];
-  }
-  double h=A[3][3];
-  for(k=0;k<3;k++) h+=A[3][k];
-  for(k=0;k<3;k++) C[k] /= h;
-}
-
-/* C <- A(B) */
-void useMatrix(Matrix3d A,const double B[3],double C[3]) {
-  int i,k;
-  for(i=0;i<3;i++) {
-    C[i] = A[i][3];
-    for(k=0;k<3;k++)
-      C[i] += A[i][k] * B[k];
-  }
-}
-
 /* C <- A */
 void assign(const Matrix4d A,Matrix4d C) {
   int i,j;
diff -ru trackballs-1.1.4.orig/src/glHelp.h trackballs-1.1.4/src/glHelp.h
--- trackballs-1.1.4.orig/src/glHelp.h	2006-08-05 11:22:32.000000000 -0400
+++ trackballs-1.1.4/src/glHelp.h	2011-04-12 12:04:16.689745593 -0400
@@ -57,8 +57,6 @@
 void zero(double[3]);
 
 void debugMatrix(Matrix4d);
-void useMatrix(Matrix4d,const double[3],double[3]);
-void useMatrix(Matrix3d,const double[3],double[3]);
 void identityMatrix(Matrix4d);
 void assign(const Matrix4d,Matrix4d);
 void matrixMult(Matrix4d,Matrix4d,Matrix4d);