Add information regarding polygon's normal calculation

liberostelios · liberostelios · commit a2da64a47bf8 · 2017-10-07T13:29:32.000+02:00
diff --git a/src/3d/qgstessellator.cpp b/src/3d/qgstessellator.cpp
@@ -113,6 +113,8 @@ static void _makeWalls( const QgsCurve &ring, bool ccw, float extrusionHeight, Q
 
 static QVector3D _calculateNormal( const QgsCurve *curve )
 {
+  // Calculate the polygon's normal vector, based on Newell's method
+  // https://www.khronos.org/opengl/wiki/Calculating_a_Surface_Normal
   QgsVertexId::VertexType vt;
   QgsPoint pt1, pt2;
   QVector3D normal( 0, 0, 0 );

Original file line number	Diff line number	Diff line change
`@@ -113,6 +113,8 @@ static void _makeWalls( const QgsCurve &ring, bool ccw, float extrusionHeight, Q`
`113`	`113`
`114`	`114`	`static QVector3D _calculateNormal( const QgsCurve *curve )`
`115`	`115`	`{`
	`116`	`+ // Calculate the polygon's normal vector, based on Newell's method`
	`117`	`+ // https://www.khronos.org/opengl/wiki/Calculating_a_Surface_Normal`
`116`	`118`	`QgsVertexId::VertexType vt;`
`117`	`119`	`QgsPoint pt1, pt2;`
`118`	`120`	`QVector3D normal( 0, 0, 0 );`