src/jelly/ClosedShape.cpp

   1 #include "ClosedShape.h"
   2
   3 #include "VectorTools.h"
   4
   5
   6 namespace JellyPhysics {
   7
   8 void ClosedShape::begin () {
   9   mLocalVertices.clear();
  10 }
  11
  12
  13 int ClosedShape::addVertex (const Vector2 &vec) {
  14   mLocalVertices.push_back(vec);
  15   return mLocalVertices.size();
  16 }
  17
  18
  19 void ClosedShape::finish (bool recenter) {
  20   if (recenter) {
  21     // find the average location of all of the vertices, this is our geometrical center
  22     Vector2 center = Vector2::Zero;
  23     unsigned int c = mLocalVertices.size();
  24     for (unsigned int i = 0; i < c; ++i) center += mLocalVertices[i];
  25     center /= (float)c;
  26     // now subtract this from each element, to get proper "local" coordinates
  27     for (unsigned int i = 0; i < c; ++i) mLocalVertices[i] -= center;
  28   }
  29 }
  30
  31
  32 Vector2List ClosedShape::transformVertices (const Vector2 &worldPos, float angleInRadians, const Vector2 &scale) const {
  33   Vector2List ret = mLocalVertices;
  34   Vector2 v;
  35   unsigned int c = ret.size();
  36   for (unsigned int i = 0; i < c; ++i) {
  37     // rotate the point, and then translate
  38     v = ret[i]*scale;
  39     v = JellyPhysics::VectorTools::rotateVector(v, angleInRadians);
  40     v += worldPos;
  41     ret[i] = v;
  42   }
  43   return ret;
  44 }
  45
  46
  47 void ClosedShape::transformVertices (const Vector2 &worldPos, float angleInRadians, const Vector2 &scale, Vector2List &outList) const {
  48   float c = cosf(angleInRadians);
  49   float s = sinf(angleInRadians);
  50   Vector2List::iterator out = outList.begin();
  51   for (Vector2List::const_iterator it = mLocalVertices.begin(); it != mLocalVertices.end(); ++it, ++out) {
  52     // rotate the point, and then translate
  53     Vector2 v =(*it)*scale;
  54     v = JellyPhysics::VectorTools::rotateVector(v, c, s);
  55     v += worldPos;
  56     (*out) = v;
  57   }
  58 }
  59
  60 }