Changeset 7677 for code/trunk/src/modules/objects

Timestamp:

Nov 26, 2010, 1:25:56 PM (14 years ago)

Author:

dafrick

Message:

Adding yet another class of ForceFields and using it in The Time Machine.

Location:

code/trunk/src/modules/objects

Files:

• ForceField.cc (modified) (6 diffs)
• ForceField.h (modified) (3 diffs)

code/trunk/src/modules/objects/ForceField.cc

@@ -44 +44 @@
     /*static*/ const std::string ForceField::modeTube_s = "tube";
     /*static*/ const std::string ForceField::modeSphere_s = "sphere";
+    /*static*/ const std::string ForceField::modeInvertedSphere_s = "invertedSphere";
 
     /**
@@ -79 +80 @@
         XMLPortParam(ForceField, "velocity", setVelocity, getVelocity, xmlelement, mode).defaultValues(100);
         XMLPortParam(ForceField, "diameter", setDiameter, getDiameter, xmlelement, mode).defaultValues(500);
-        XMLPortParam(ForceField, "length"  , setLength  , getLength  , xmlelement, mode).defaultValues(2000);
+        XMLPortParam(ForceField, "length", setLength  , getLength  , xmlelement, mode).defaultValues(2000);
         XMLPortParam(ForceField, "mode", setMode, getMode, xmlelement, mode);
     }
@@ -102 +103 @@
 
                 // Vector from the center of the force field to the object its acting on.
-                // TODO: This could probably be simplified.
                 Vector3 distanceVector = it->getWorldPosition() - (this->getWorldPosition() + (this->halfLength_ * direction));
 
-                // The object is outside of the length of the ForceField.
+                // The object is outside a ball around the center with radius length/2 of the ForceField.
                 if(distanceVector.length() > this->halfLength_)
                     continue;
@@ -137 +137 @@
             }
         }
+        else if(this->mode_ == forceFieldMode::invertedSphere)
+        {
+            // Iterate over all objects that could possibly be affected by the ForceField.
+            for (ObjectList<MobileEntity>::iterator it = ObjectList<MobileEntity>::begin(); it != ObjectList<MobileEntity>::end(); ++it)
+            {
+                Vector3 distanceVector = this->getWorldPosition() - it->getWorldPosition();
+                float distance = distanceVector.length();
+                // If the object is within 'radius' distance and no more than 'length' away from the boundary of the sphere.
+                float range = this->radius_ - this->halfLength_*2;
+                if (distance < this->radius_ && distance > range)
+                {
+                    distanceVector.normalise();
+                    // Apply a force proportional to the velocity, with highest force at the boundary of the sphere, linear decreasing until reaching a distance of 'radius-length' from the origin, where the force reaches zero.
+                    it->applyCentralForce((distance-range)/range * this->velocity_ * distanceVector);
+                }
+            }
+        }
     }
 
@@ -151 +168 @@
         else if(mode == ForceField::modeSphere_s)
             this->mode_ = forceFieldMode::sphere;
+        else if(mode == ForceField::modeInvertedSphere_s)
+            this->mode_ = forceFieldMode::invertedSphere;
         else
         {
@@ -172 +191 @@
             case forceFieldMode::sphere:
                 return ForceField::modeSphere_s;
+            case forceFieldMode::invertedSphere:
+                return ForceField::modeInvertedSphere_s;
             default:
                 return ForceField::modeTube_s;

code/trunk/src/modules/objects/ForceField.h

@@ -54 +54 @@
         enum Value {
             tube, //!< The ForceField has a tube shape.
-            sphere //!< The ForceField has a spherical shape.
+            sphere, //!< The ForceField has a spherical shape.
+            invertedSphere //!< The ForceField has a spherical shape but "inverted" behavior.
         };
     }
@@ -67 +68 @@
         - @b length The length of the ForceField. Default is 2000.
         - @b mode The mode the ForceField is in. For mode:
-            - <em>tube</em> A ForceField which exerts force only in the direction it is oriented. The force is only exerted on objects that are in a tube of length <em>length</em> and diameter <em>diameter</em>. The magintude of the force is proportional to the <em>velocity</em>, being highest when an object is in the middle of the tube (radius-wise), linearly decreasing with greater radii and finally reaching zero, when the object is <code>diameter/2</code> away from the orientation vector.
+            - <em>tube</em> A ForceField which exerts force only in the direction it is oriented. The force is only exerted on objects that are in a tube of length <em>length</em> and diameter <em>diameter</em> (with rounded start and end faces, so in fact the <em>length</em> parameter specifies a ball with <code>origin + length/2</code> as the center and <code>length/2</code> as the radius). The magintude of the force is proportional to the <em>velocity</em>, being highest when an object is in the middle of the tube (radius-wise), linearly decreasing with greater radii and finally reaching zero, when the object is <code>diameter/2</code> away from the orientation vector.
             - <em>sphere</em> A Force Field which exerts force radially away from itself, with the greatest magnitude (proportional to <em>velocity</em>) being in the origin of the ForceField, linearly decreasing with respect to the distance to the origin and finally reaching zero at distance <code>diameter/2</code>.
             Default is <em>tube</em>.
+            - <em>invertedSphere</em> 
 
     @author
@@ -134 +136 @@
             static const std::string modeTube_s;
             static const std::string modeSphere_s;
+            static const std::string modeInvertedSphere_s;
 
             float velocity_; //!< The velocity of the ForceField.