[Plib-cvs] plib/src/sg sg.cxx,1.38,1.39 sg.h,1.50,1.51

[Steve B. <sj...@us...>]

Update of /cvsroot/plib/plib/src/sg
In directory sc8-pr-cvs1:/tmp/cvs-serv5321/plib/src/sg

Modified Files:
	sg.cxx sg.h 
Log Message:
Angle calculation routines changed to return degree results.


Index: sg.cxx
===================================================================
RCS file: /cvsroot/plib/plib/src/sg/sg.cxx,v
retrieving revision 1.38
retrieving revision 1.39
diff -u -d -r1.38 -r1.39
--- sg.cxx	9 Sep 2002 09:07:03 -0000	1.38
+++ sg.cxx	7 Oct 2003 03:00:08 -0000	1.39
@@ -156,10 +156,12 @@
 }
 
 // -dw- inconsistent linkage!
+
 float sgTriArea( sgVec3 p0, sgVec3 p1, sgVec3 p2 )
 {
   /* 
     From comp.graph.algorithms FAQ
+
 	2A(P) = abs(N.(sum_{i=0}^{n-1}(v_i x v_{i+1})))
 	This is an optimized version for a triangle
[...180 lines suppressed...]
 {
+  // nornmal has to be normalized.
   sgVec3 nv1, nv2 ;
 
   sgNormalizeVec3 ( nv1, v1 ) ;
@@ -1001,6 +1001,14 @@
 
     dst->hpr[2] = sgATan2 ( sr, cr ) ;
   }
+}
+
+
+void sgMakeNormal(sgVec2 dst, const sgVec2 a, const sgVec2 b )
+{
+  sgSubVec2 ( dst, b, a ) ;
+  float tmp = dst [ 0 ] ; dst [ 0 ] = -dst [ 1 ] ; dst [ 1 ] = tmp ;
+  sgNormaliseVec2 ( dst ) ;
 }
 
 

Index: sg.h
===================================================================
RCS file: /cvsroot/plib/plib/src/sg/sg.h,v
retrieving revision 1.50
retrieving revision 1.51
diff -u -d -r1.50 -r1.51
--- sg.h	15 Sep 2003 21:53:53 -0000	1.50
+++ sg.h	7 Oct 2003 03:00:11 -0000	1.51
@@ -854,6 +854,9 @@
   sgReflectInPlaneVec3 ( dst, dst, plane ) ;
 }
 
+extern void sgMakeNormal    ( sgVec2 dst, const sgVec3 a, const sgVec3 b ) ;
+
+
 extern void sgMakeNormal    ( sgVec3 dst, const sgVec3 a, const sgVec3 b, const sgVec3 c ) ;
 
 
@@ -888,21 +891,26 @@
 float sgTriArea( sgVec3 p0, sgVec3 p1, sgVec3 p2 );
 
 
-// Fast code. Result is in the range  0..pi:
+// Fast code. Result is in the range  0..180:
 inline SGfloat sgAngleBetweenNormalizedVec3 ( sgVec3 v1, sgVec3 v2 )
 {
   float f = sgScalarProductVec3 ( v1, v2 ) ;
   
-  return (float)(acos((f>=1.0f)?1.0f:(f<=-1.0f)?-1.0f:f)*SG_RADIANS_TO_DEGREES) ;
+  return (float) acos ( ( f >=  1.0f ) ?  1.0f :
+                        ( f <= -1.0f ) ? -1.0f : f ) * 
+                                 SG_RADIANS_TO_DEGREES ;
 }
 
-// Fast code. Result is in the range  0..pi:
+// Fast code. Result is in the range  0..180:
+
 SGfloat sgAngleBetweenVec3 ( sgVec3 v1, sgVec3 v2 );
 
-// all three have to be normalized. Slow code. Result is in the range  0..2*pi:
+// All three have to be normalized. Slow code. Result is in the range  0..360:
+
 SGfloat sgAngleBetweenNormalizedVec3 (sgVec3 first, sgVec3 second, sgVec3 normal);
 
-// normal has to be normalized. Slow code. Result is in the range  0..2*pi:
+// Normal has to be normalized. Slow code. Result is in the range  0..360:
+
 SGfloat sgAngleBetweenVec3 ( sgVec3 v1, sgVec3 v2, sgVec3 normal );
 
 class sgSphere