adapted comments in localFrame and import2tablesSurface::importPlyPTM and...

adapted comments in localFrame and import2tablesSurface::importPlyPTM and secured localFrame (no more possibility of generating a zero vector)

include/Algo/Import/import2tablesSurface.hpp

@@ -674,8 +674,7 @@ bool MeshTablesSurface<PFP>::importPlyPTMgeneric(const std::string& filename, st
  * @param attrNames : reference that will be filled with the attribute names ;
  *  - 1 attrName for geometric position (VEC3)
  *  - 3 attrNames for local frame (3xVEC3) : Tangent, Bitangent and Normal vector
- *  - 6 attrNames for the function coefficients (6xVEC3) : 6 RGB coefficients being successively the constants, the linears (v then u) and the quadratics : a0 + a1*v + a2*u + a3*u*v + a4*v^2 + a5*u^2.
- * @return bool : success.
+ *  - 6 attrNames for the function coefficients (6xVEC3) : 6 RGB coefficients being successively the quadratic members, the linears and the constants (u then v) : a*u^2 + b*v^2 + c*uv + d*u + e*v +f.
   * @return bool : success.
  */
 template <typename PFP>

include/Utils/localFrame.h

@@ -179,9 +179,18 @@ public: // methods
 	} ;
 
 private : // private constants
-	const VEC3 T ;
-	const VEC3 B ;
-	const VEC3 N ;
+	// (T,B,N) can be any orthonormal direct frame
+	// zeros are not recommended since they can
+	// generate zero vectors after a dot product
+	static const REAL Tx = 0.267261 ;
+	static const REAL Ty = 0.534522 ;
+	static const REAL Tz = 0.801784 ;
+	static const REAL Bx = 0.844416 ;
+	static const REAL By = -0.530776 ;
+	static const REAL Bz = 0.0723785 ;
+	static const REAL Nx = 0.464255 ;
+	static const REAL Ny = 0.657695 ;
+	static const REAL Nz = -0.593215 ;
 } ;
 
 } // Utils

include/Utils/localFrame.hpp

@@ -28,10 +28,7 @@ namespace CGoGN {
 namespace Utils {
 
 template<typename PFP>
-LocalFrame<PFP>::LocalFrame(const VEC3& T, const VEC3& B, const VEC3& N) :
-	T(1,0,0), // (T,B,N) can be any orthonormal direct frame
-	B(0,1,0), // but has to be initialized exactly the same
-	N(0,0,1)  // in every constructor !
+LocalFrame<PFP>::LocalFrame(const VEC3& T, const VEC3& B, const VEC3& N)
 {
 	m_T = T ;
 	m_B = B ;
@@ -39,11 +36,11 @@ LocalFrame<PFP>::LocalFrame(const VEC3& T, const VEC3& B, const VEC3& N) :
 }
 
 template<typename PFP>
-LocalFrame<PFP>::LocalFrame(const VEC3& compressedFrame) :
-	T(1,0,0), // (T,B,N) can be any orthonormal direct frame
-	B(0,1,0), // but has to be initialized exactly the same
-	N(0,0,1)  // in every constructor !{
+LocalFrame<PFP>::LocalFrame(const VEC3& compressedFrame)
 {
+	const VEC3 T(Tx,Ty,Tz) ;
+	const VEC3 N(Nx,Ny,Nz) ;
+
 	// get known data
 	const REAL& theta1 = compressedFrame[0] ;
 	const REAL& phi = compressedFrame[1] ;
@@ -60,6 +57,10 @@ typename Geom::Vector<3,typename PFP::REAL> LocalFrame<PFP>::getCompressed() con
 {
 	VEC3 res ;
 
+	const VEC3 T(Tx,Ty,Tz) ;
+	const VEC3 B(Bx,By,Bz) ;
+	const VEC3 N(Nx,Ny,Nz) ;
+
 	REAL& theta1 = res[0] ;
 	REAL& phi = res[1] ;
 	REAL& theta2 = res[2] ;