Collision detection for Shapes

intersect.cpp

#include <Siv3D.hpp>


template <class T>
const bool intersect(const T& shape1, const Shape& shape2)
{
	const Shape::Type type = shape2.type();

	switch (type)
	{
	case Shape::Type::Circle:
		return shape1.intersects(shape2.storage.circle);

	case Shape::Type::RectF:
		return shape1.intersects(shape2.storage.rectF);

	case Shape::Type::Quad:
		return shape1.intersects(*shape2.storage.quad);

	case Shape::Type::Triangle:
		return shape1.intersects(shape2.storage.triangle);
	}

	return false;
}

void Main()
{
	Graphics::SetBackground(Palette::Slategray);


	const Vec2 pos { 640 / 2, 480 / 2 };

	Array<Shape> shapes;
	shapes.push_back(Shape(Circle(pos, 50))); //Circle
	shapes.push_back(Shape(RectF(pos.movedBy(-130, -130), 100, 200))); //RectF
	shapes.push_back(Shape(RectF(pos.movedBy(0, -100), 120, 100).rotated(45_deg))); //Quad
	shapes.push_back(Shape(Triangle(pos, pos.movedBy(140, 0), pos.movedBy(0, 120)))); //Triangle


	while (System::Update())
	{
		for (auto& s : shapes)
		{
			if (intersect(Vec2(Mouse::Pos()), s))
			{
				s.draw(Palette::Orange);
			}

			s.drawFrame(3);
		}
	}
}