gravity.cpp

   1 #include "gravity.h"
   2 #include <math.h>
   3
   4 void GravityManager::subscribe(Thing* thing) {
   5         things.insert(thing);
   6 }
   7
   8 void GravityManager::addPlatform(Platform* linha) {
   9         platforms.insert(linha);
  10 }
  11
  12 void GravityManager::deleteThing(Thing* thing) {
  13         things.erase(things.find(thing));
  14 }
  15
  16 void GravityManager::update() {
  17         std::set<Thing*>::iterator it;
  18         std::set<Platform*>::iterator plat;
  19         for (it = things.begin(); it != things.end(); it++) {
  20                 (*it)->addSpeed(0,(*it)->gravityRate);
  21                 double timeToCollide = 9999;
  22                 Platform* collidedWith = NULL;
  23                 (*it)->onGround = false;
  24                 for (plat = platforms.begin(); plat != platforms.end(); plat++) {
  25                         double t;
  26                         if (checkGround(*it, *plat, t)) {
  27                                 timeToCollide = t;
  28                                 collidedWith = *plat;
  29                                 double angle = collidedWith->angle();
  30                                 double slope = angle / (PI/2);
  31                                 if (slope != 1 && (*it)->getSpeedY() >= 0)
  32                                         (*it)->onGround = true;
  33                                 if (slope == 1) { //colisao com parede
  34                                         double dir = sign((*it)->getSpeedX());
  35                                         (*it)->setSpeed(dir*-3,(*it)->getSpeedY());
  36                                 }
  37                                 else if ((*it)->getSpeedY() >= (*it)->gravityRate) {
  38                                         (*it)->setSpeed((*it)->getSpeedX(),(*it)->getSpeedY()*timeToCollide);
  39                                 }
  40                                 if ((*it)->getSpeedY() < 0) {
  41                                 }
  42                         }
  43                 }
  44         }
  45 }
  46
  47 void GravityManager::removePlatforms() {
  48         platforms.clear();
  49 }
  50
  51 //caso ocorra colisao, t retorna em quanto tempo ela ocorrera
  52 bool GravityManager::checkGround(Thing* thing, Platform *platform, double &t) {
  53         if (platform->isPassable() && thing->bypass)
  54                 return false;
  55         Linha l1 = thing->getBaseLine();
  56         l1.translate(thing->getPosition());
  57         Linha l2 = l1;
  58         l2.translate(thing->getSpeed());
  59         Linha l3(l1.vertices[0],l2.vertices[0]);
  60         Linha l4(l1.vertices[1],l2.vertices[1]);
  61         Linha plat = platform->getLine();
  62         t = 9999;
  63         if (linesIntersect(l1,plat))
  64                 t = 0;
  65         else {
  66                 if (linesIntersect(l3,plat))
  67                         t = std::min(t,timeToIntersection(l3,plat));
  68                 if (linesIntersect(l4,plat))
  69                         t = std::min(t,timeToIntersection(l4,plat));
  70                 if (linesIntersect(l2,plat))
  71                         t = std::min(t,1.0);
  72         }
  73         return (0<= t && t <= 1.0);
  74 }