What does it mean?

[Farabi]

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CVector3 LP1
CVector3 TP1
float Dist1 = (LP1-TP1).Dot( Normal );


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bool CheckLineTri( CVector3 TP1, CVector3 TP2, CVector3 TP3, CVector3 LP1, CVector3 LP2, CVector3 &HitPos)
  {
   CVector3 Normal, IntersectPos;

   // Find Triangle Normal
   Normal = CrossProduct( TP2 - TP1, TP3 - TP1 );
   Normal.Normalize(); // not really needed

   // Find distance from LP1 and LP2 to the plane defined by the triangle
   float Dist1 = (LP1-TP1).Dot( Normal );
   float Dist2 = (LP2-TP1).Dot( Normal );
   if ( (Dist1 * Dist2) >= 0.0f) return false;  // line doesn't cross the triangle.
   if ( Dist1 == Dist2) return false;// line and plane are parallel

   // Find point on the line that intersects with the plane
   IntersectPos = LP1 + (LP2-LP1) * ( -Dist1/(Dist2-Dist1) );

   // Find if the interesection point lies inside the triangle by testing it against all edges
   CVector3 vTest;
   vTest = CrossProduct( Normal, TP2-TP1 );
   if ( Dot( vTest, IntersectPos-TP1) < 0.0f ) return false;
   vTest = CrossProduct( Normal, TP3-TP2 );
   if ( Dot( vTest, IntersectPos-TP2) < 0.0f ) return false;
   vTest = CrossProduct( Normal, TP1-TP3 );
   if ( Dot( vTest, IntersectPos-TP1) < 0.0f ) return false;

   HitPos = IntersectPos;
   return true;
   }



Substract the vector and then multiply with the dot product of normal, or substract and then dot product and put the result to normal?

[qWord]

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dist1 = (LP1-TP1) * Normal // "*" == dot product