Use raycasting instead of OpenGL selection mode to pick tracks

[r2c2.git] / source / libr2c2 / trackpart.cpp

diff --git a/source/libr2c2/trackpart.cpp b/source/libr2c2/trackpart.cpp
index f677c703ee5a7e89f7ffa9d241fbaa69754f433c..d60d374091556b2f89441e9febfc4ddda4ebd7fa 100644 (file)
--- a/source/libr2c2/trackpart.cpp
+++ b/source/libr2c2/trackpart.cpp
@@ -1,7 +1,7 @@
 /* $Id$
 
 This file is part of R²C²
-Copyright © 2006-2010  Mikkosoft Productions, Mikko Rasa
+Copyright © 2006-2011  Mikkosoft Productions, Mikko Rasa
 Distributed under the GPL
 */
 
@@ -92,6 +92,33 @@ TrackPart *TrackPart::get_link(unsigned i) const
        return links[i];
 }
 
+bool TrackPart::collide_ray(const Vector &start, const Vector &ray, float width) const
+{
+       Vector local_start(start.x-pos.x, start.y-pos.y, start.z);
+       float c = cos(dir);
+       float s = sin(dir);
+       local_start = Vector(c*local_start.x+s*local_start.y, c*local_start.y-s*local_start.x, local_start.z);
+       Vector local_ray(c*ray.x+s*ray.y, c*ray.y-s*ray.x, ray.z);
+
+       float d = -local_start.z/local_ray.z;
+       if(d<0)
+               return false;
+
+       Vector base(local_start.x+d*local_ray.x, local_start.y+d*local_ray.y);
+
+       if(radius)
+       {
+               base.y -= radius;
+               if(radius<0)
+                       base.y = -base.y;
+               float r = sqrt(base.x*base.x+base.y*base.y)-abs(radius);
+               float a = atan2(base.x, -base.y);
+               return (a>=0 && a<=length && r>=-width/2 && r<=width/2);
+       }
+       else
+               return (base.x>=0 && base.x<=length && base.y>=-width/2 && base.y<=width/2);
+}
+
 
 TrackPart::Loader::Loader(TrackPart &p):
        Msp::DataFile::BasicLoader<TrackPart>(p)