cocos2dx 碰撞检测
//用平台封装的函数进行碰撞检测
//将砖块精灵放入一个数组（容器）之中然后一 一进行碰撞检测
bool MyMap::isCollideWithHeroX()
{
for(auto x:Road)
{
if(x->boundingBox().intersectsRect(myHero->getSprite()->boundingBox())) //boundingBox().intersectsRect(）这个函数获取的是精灵的标准矩形，如果要更精确的检测可以自己获取一个不规则多边形进行检测
{
return true;
}
}
return false;
}
//网上学习
检测矩形与矩形碰撞的函数：
bool intersectsRect(const CCRect &rect) 使用方法： rect1.intersectsRect(rect2);
检测点与矩形碰撞的函数： bool containsPoint(const CCPoint &point) 使用方法： rect.containsPoint(point);
下面重点说矩形与圆形的碰撞检测： PS：先说一下cocos2d-x中的矩形Rect，Rect的构造有四个参数，x, y, width, height,如下图所示
//
// CGCircle.h
// HelloCpp
//
// Created by Mike on 14-1-16.
//
//
#ifndef __HelloCpp__CGCircle__
#define __HelloCpp__CGCircle__
#include <iostream>
#include "cocos2d.h"
using namespace std;
using namespace cocos2d;
class CGCircle
{
private:
//float _radius; //半径
//Point _position; //圆心
public:
CC_SYNTHESIZE(float, _radius, Radius);
CC_SYNTHESIZE(Point, _position, Position);
CGCircle(float radius, Point position): _radius(radius), _position(position){};
bool isContainRect(Rect rect);
};
#endif /* defined(__HelloCpp__CGCircle__) */</iostream>
// CGCircle.cpp
// HelloCpp
//
// Created by Mike on 14-1-16.
//
//
#include "CGCircle.h"
bool CGCircle::isContainRect(Rect rect)
{
bool _isContian = false;
Point orign = _position; //圆心，新建坐标系的原点
//圆的外切正方形 Rect(x, y, width, heigth) x,y是原点，左下顶点
Rect square = Rect::Rect(_position.x - _radius, _position.y - _radius,
2 * _radius, 2 * _radius);
do {
Point rectVertex0 = rect.origin; //左下
Point rectVertex1 = rect.origin + Point(rect.size.width, 0); //右下
Point rectVertex2 = rect.origin + Point(rect.size.width, rect.size.height); //右上
Point rectVertex3 = rect.origin + Point(0, rect.size.height); //左上
Point pos[] = {rectVertex0, rectVertex1, rectVertex2, rectVertex3};
if ((pos[1].x - orign.x) * (pos[3].x - orign.x) > 0 &&
(pos[1].y - orign.y) * (pos[3].y - orign.y) > 0)
{
//右下顶点和左上顶点在同一象限，说明整个矩形位于一个象限内 若各顶点至少有一个在圆内则相交
for (int i = 0; i < 4; i++) {
//判断矩形四个顶点是否至少有一个位于圆内
if (((pos[i].x - orign.x) * (pos[i].x - orign.x)
+ (pos[i].y - orign.y) * (pos[i].y - orign.y))
<= _radius * _radius)
{
goto next;
}
}
}
if (square.intersectsRect(rect)) {
goto next;
}
for (int i = 0; i < 4; i++) {
if (pos[i] == orign) {
goto next;
}
}
break;
next:
_isContian = true;
} while (0);
return _isContian;
}
Size visibleSize = Director::getInstance()->getVisibleSize();
auto circleS = Sprite::create("circle.png");
circleS->setPosition(Point(visibleSize.width/2, visibleSize.height/2));
this->addChild(circleS, 0);
auto rectS = Sprite::create("rect.png");
rectS->setPosition(Point(circleS->getPositionX() - 100, circleS->getPositionY()));
this->addChild(rectS, 0);
CGCircle circle0 = CGCircle(circleS->getContentSize().width/2, circleS->getPosition());
Rect rect0 = Rect(rectS->getPositionX() - rectS->getContentSize().width/2,
rectS->getPositionY() - rectS->getContentSize().height/2,
rectS->getContentSize().width, rectS->getContentSize().height);
if (circle0.isContainRect(rect0)) {
CCLOG("circleS与rectS碰撞了");
}
else CCLOG("circleS与rectS未碰撞");
float radius = 30.0;
Point position = Point(300, 300);
CGCircle circle = CGCircle(radius, position);
Rect rect1 = Rect(280, 290, 10, 30);
if (circle.isContainRect(rect1))
{
CCLOG("矩形1与圆碰撞了");
}
Rect rect2 = Rect(210, 290, 10, 30);
if (! circle.isContainRect(rect2))
{
CCLOG("矩形2与圆未碰撞");
}