Re: [Plib-users] culling problems w/ off-axis projection

[Melchior F. <mel...@gm...>]

Sending again, because I used the wrong email address. Twice! Sigh.



* John F. Fay -- Monday 31 May 2010:
> It uses the functions "_isnan"  and "_isfinite" which are just
> fine on my Windows/MSVC platform.

For some reason MICROS~1 is in love with these underscore functions,
which are, in the real world, just isnan() and isfinite(). So this
doesn't compile on Linux:

  sg.cxx: In function ‘void sgQuatToAngleAxis(float*, float*, const float*)’:
  sg.cxx:1311: error: ‘_isnan’ was not declared in this scope
  sg.cxx:1311: error: ‘_finite’ was not declared in this scope



I suggest to do something like this:


diff --git a/src/sg/sg.cxx b/src/sg/sg.cxx
index 0e182fb..b6aa05c 100644
--- a/src/sg/sg.cxx
+++ b/src/sg/sg.cxx
@@ -24,6 +24,12 @@
 
 #include "sg.h"
 
+#ifdef UL_WIN32
+#  define isnan _isnan
+#  define finite _finite
+#endif
+
+
 sgVec3 _sgGravity = { 0.0f, 0.0f, -9.8f } ;
 
 void sgVectorProductVec3 ( sgVec3 dst, const sgVec3 a, const sgVec3 b )
@@ -1308,7 +1314,7 @@ void sgQuatToAngleAxis ( SGfloat *angle,
 void sgQuatToAngleAxis ( SGfloat *angle, sgVec3 axis, const sgQuat src )
 {
   SGfloat a = (SGfloat) acos ( src[SG_W] ) ;
-  if ( _isnan(a) || !_finite(a) ) {
+  if ( isnan(a) || !finite(a) ) {
     ulSetError(UL_WARNING,"sgQuatToAngleAxis: acos(%f) %f",src[SG_W],a);
     if ( src[SG_W] >= 1 ) a = 0;
     else if ( src[SG_W] <= -1 ) a = SG_PI;

m.