Circle.cpp

Go to the documentation of this file.

/*
   Copyright 2022 Rishi Challa
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at
 
       http://www.apache.org/licenses/LICENSE-2.0
 
   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/
 
#include "Circle.hpp"
 
#include <Kale/Math/RotatedRect/RotatedRect.hpp>
#include <Kale/Math/Rect/Rect.hpp>
#include <Kale/Math/Ray/Ray.hpp>
#include <Kale/Math/Line/Line.hpp>
 
#include <stdexcept>
 
using namespace Kale;
 
Circle::Circle() : center(0, 0), radius(1) {
    // Empty Body
}
 
Circle::Circle(const Vector2f& center, float radius) : center(center), radius(radius) {
    // Empty Body
}
 
Rect Circle::getBoundingBox() const {
    return {center + Vector2f{-radius, radius}, center + Vector2f{radius, -radius}};
}
 
bool Circle::pointCollision(Vector2f point) const {
    Vector2f tmp = point - center;
    return tmp.dot(tmp) <= radius * radius;
}
 
bool Circle::rectCollision(RotatedRect rect) const {
    if (rect.pointCollision(center)) return true;
    return lineCollision({rect.point1, rect.point2}) || lineCollision({rect.point2, rect.point3}) ||
        lineCollision({rect.point3, rect.point4}) || lineCollision({rect.point4, rect.point1});
}
 
bool Circle::rectCollision(Rect rect) const {
    return rect.circleCollision(*this);
}
 
bool Circle::circleCollision(Circle circle) const {
    Vector2f tmp = circle.center - center;
    return tmp.dot(tmp) <= pow(radius + circle.radius, 2.0f);
}
 
bool Circle::rayCollision(Ray ray) const {
    Vector2f proj = (center - ray.origin).project(ray.direction);
    if (sign(proj.x) != sign(ray.direction.x)) proj = ray.origin;
    else proj += ray.origin;
    return pointCollision(proj);
}
 
bool Circle::lineCollision(Line line) const {
    Vector2f proj = line.point1 + (center - line.point1).project(line.point2 - line.point1);
    if (proj.x > line.point2.x) proj = line.point2;
    else if (proj.x < line.point1.x) proj = line.point1;
    return pointCollision(proj);
}