Changeset 778 for GTP/trunk/Lib/Illum/IBRBillboardCloudTrees/OGRE/include/BBC

Timestamp:

04/21/06 19:56:55 (19 years ago)

Author:

igarcia

Message:

 

File:

• GTP/trunk/Lib/Illum/IBRBillboardCloudTrees/OGRE/include/BBC/BBCUtil.h (modified) (2 diffs)

GTP/trunk/Lib/Illum/IBRBillboardCloudTrees/OGRE/include/BBC/BBCUtil.h

@@ -5 +5 @@
 
 namespace BBC {
+
+const Ogre::Real EPSILON_INTERSECT = 0.00000001;
 
 class _BBCExport Util
@@ -35 +37 @@
         }
 
+        // Calculate the line segment PaPb that is the shortest route between
+        // two lines P1P2 and P3P4. Calculate also the values of mua and mub where
+        //   Pa = P1 + mua (P2 - P1)
+        //       Pb = P3 + mub (P4 - P3)
+        // Return false if no solution exists.
+
+        static int lineLineIntersect(
+                Ogre::Vector3 p1, Ogre::Vector3 p2, Ogre::Vector3 p3, Ogre::Vector3 p4, Ogre::Vector3 *pa, Ogre::Vector3 *pb,
+                Ogre::Real *mua, Ogre::Real *mub)
+        {
+                Ogre::Vector3 p13,p43,p21;
+                Ogre::Real d1343,d4321,d1321,d4343,d2121;
+                Ogre::Real numer,denom;
+
+                p13.x = p1.x - p3.x;
+                p13.y = p1.y - p3.y;
+                p13.z = p1.z - p3.z;
+                p43.x = p4.x - p3.x;
+                p43.y = p4.y - p3.y;
+                p43.z = p4.z - p3.z;
+                if (Ogre::Math::Abs(p43.x)  < EPSILON_INTERSECT && Ogre::Math::Abs(p43.y)  < EPSILON_INTERSECT && Ogre::Math::Abs(p43.z)  < EPSILON_INTERSECT)
+                {
+                        return(false);
+                }
+                p21.x = p2.x - p1.x;
+                p21.y = p2.y - p1.y;
+                p21.z = p2.z - p1.z;
+                if (Ogre::Math::Abs(p21.x)  < EPSILON_INTERSECT && Ogre::Math::Abs(p21.y)  < EPSILON_INTERSECT && Ogre::Math::Abs(p21.z)  < EPSILON_INTERSECT)
+                {
+                        return(false);
+                }
+
+                d1343 = p13.x * p43.x + p13.y * p43.y + p13.z * p43.z;
+                d4321 = p43.x * p21.x + p43.y * p21.y + p43.z * p21.z;
+                d1321 = p13.x * p21.x + p13.y * p21.y + p13.z * p21.z;
+                d4343 = p43.x * p43.x + p43.y * p43.y + p43.z * p43.z;
+                d2121 = p21.x * p21.x + p21.y * p21.y + p21.z * p21.z;
+
+                denom = d2121 * d4343 - d4321 * d4321;
+                if (Ogre::Math::Abs(denom) < EPSILON_INTERSECT)
+                {
+                        return(false);
+                }
+                numer = d1343 * d4321 - d1321 * d4343;
+
+                *mua = numer / denom;
+                *mub = (d1343 + d4321 * (*mua)) / d4343;
+
+                pa->x = p1.x + *mua * p21.x;
+                pa->y = p1.y + *mua * p21.y;
+                pa->z = p1.z + *mua * p21.z;
+                pb->x = p3.x + *mub * p43.x;
+                pb->y = p3.y + *mub * p43.y;
+                pb->z = p3.z + *mub * p43.z;
+
+                return(true);
+        }
 };
 
 /*
-extern "C" _BBCExport double fround(double n, unsigned d)
+extern "C" _BBCExport Ogre::Real fround(Ogre::Real n, unsigned d)
 { 
-        return floor(n * pow((double)10.,(int) d) + .5) / pow((double)10.,(int) d);
+        return floor(n * pow((Ogre::Real)10.,(int) d) + .5) / pow((Ogre::Real)10.,(int) d);
 }
 
-extern "C" _BBCExport int iround(double x)
+extern "C" _BBCExport int iround(Ogre::Real x)
 {
       return (int)floor(x + 0.5);