src/shape/Circle.cpp

   1 /*
   2  * Circle.cpp
   3  *
   4  *  Created on: Apr 29, 2012
   5  *      Author: holy
   6  */
   7
   8 #include "Circle.h"
   9
  10 #include "AABB.h"
  11
  12 namespace shape {
  13
  14 void Circle::Translate(const Vector &delta) {
  15         center += delta;
  16 }
  17
  18 void Circle::Rotate(Scalar delta) {
  19
  20 }
  21
  22
  23 bool Circle::CheckCollision(const Shape &other, Ray &na) const {
  24         if (other.CheckCollision(*this, na)) {
  25                 na.Direction() *= -1;
  26                 return true;
  27         } else {
  28                 return false;
  29         }
  30 }
  31
  32 bool Circle::CheckCollision(const AABB &other, Ray &na) const {
  33         int xZone(
  34                         center.X() < other.Left() ? 0 : (
  35                         other.Right() < center.X() ? 2 : 1));
  36         int yZone(
  37                                 center.Y() < other.Top() ? 0 : (
  38                                 other.Bottom() < center.Y() ? 2 : 1));
  39         int zone(xZone + 3 * yZone);
  40
  41         if (zone == 4) {
  42                 na.Origin() = center;
  43                 na.Direction() = (center - other.Center()).Unit();
  44                 return true;
  45         }
  46
  47         if (zone % 2) {
  48                 if (xZone == 1) { // vertical
  49                         if (Bottom() < other.Top()) return false;
  50                         if (other.Bottom() < Top()) return false;
  51
  52                         if (Bottom() < other.Bottom()) {
  53                                 na.Origin() = Vector(center.X(), Bottom());
  54                                 na.Direction() = Vector(0, -1);
  55                         } else {
  56                                 na.Origin() = Vector(center.X(), Top());
  57                                 na.Direction() = Vector(0, 1);
  58                         }
  59
  60                         return true;
  61                 } else {
  62                         if (Right() < other.Left()) return false;
  63                         if (other.Right() < Left()) return false;
  64
  65                         if (Left() < other.Left()) {
  66                                 na.Origin() = Vector(Left(), center.Y());
  67                                 na.Direction() = Vector(-1, 0);
  68                         } else {
  69                                 na.Origin() = Vector(Right(), center.Y());
  70                                 na.Direction() = Vector(1, 0);
  71                         }
  72
  73                         return true;
  74                 }
  75         } else {
  76                 Vector near(
  77                                 yZone ? other.Right() : other.Left(),
  78                                 xZone ? other.Bottom() : other.Top());
  79                 Vector distance(Center() - near);
  80                 Scalar distanceSquared(distance.LengthSquared());
  81                 if (distanceSquared < (Radius() * Radius())) {
  82                         na.Origin() = near;
  83                         na.Direction() = distance.Unit();
  84                         return true;
  85                 } else {
  86                         return false;
  87                 }
  88         }
  89 }
  90
  91 bool Circle::CheckCollision(const Circle &other, Ray &na) const {
  92         const Vector distance(center - other.center);
  93         const Scalar distanceSquared(distance.LengthSquared());
  94         const Scalar radii(radius + other.radius);
  95
  96         if (distanceSquared < (radii * radii)) {
  97                 na.Direction() = distance.Unit();
  98                 na.Origin() = center + (na.Direction() * radius);
  99                 return true;
 100         } else {
 101                 return false;
 102         }
 103 }
 104
 105
 106 std::ostream &Circle::Write(std::ostream &out) const {
 107         return out << "Circle(" << Radius() << ", " << Center() << ')';
 108 }
 109
 110 }