osu-lazer/Symcol.Core/GameObjects/SymcolHitbox.cs

using osu.Framework.Graphics;
using OpenTK;
using Symcol.Core.Graphics.Containers;

namespace Symcol.Core.GameObjects
{
    public class SymcolHitbox : SymcolContainer
    {
        /// <summary>
        /// whether we want to do hit detection
        /// </summary>
        public int Team { get; set; }

        /// <summary>
        /// whether we want to do hit detection
        /// </summary>
        public bool HitDetection { get; set; } = true;

        /// <summary>
        /// the shape of this object (used for hit detection)
        /// </summary>
        public Shape Shape { get; }

        public SymcolHitbox(Vector2 size, Shape shape = Shape.Circle)
        {
            Anchor = Anchor.Centre;
            Origin = Anchor.Centre;

            Shape = shape;
            Size = size;

            if (Shape == Shape.Circle)
                Child = new SymcolContainer
                {
                    RelativeSizeAxes = Axes.Both,
                    CornerRadius = Width / 2
                };
            else if (Shape == Shape.Rectangle)
                Child = new SymcolContainer
                {
                    RelativeSizeAxes = Axes.Both
                };
        }

        public bool HitDetect(SymcolHitbox hitbox1, SymcolHitbox hitbox2)
        {
            if (hitbox1.HitDetection && hitbox2.HitDetection && hitbox1.Team != hitbox2.Team)
            {
                if (hitbox1.Shape == Shape.Circle && hitbox2.Shape == Shape.Circle)
                {
                    if (hitbox1.ScreenSpaceDrawQuad.AABB.IntersectsWith(hitbox2.ScreenSpaceDrawQuad.AABB))
                        return true;
                }
                else if (hitbox1.Shape == Shape.Circle && hitbox2.Shape == Shape.Rectangle || hitbox1.Shape == Shape.Rectangle && hitbox2.Shape == Shape.Circle)
                {
                    if (hitbox1.ScreenSpaceDrawQuad.AABB.IntersectsWith(hitbox2.ScreenSpaceDrawQuad.AABB))
                        return true;
                }
                else if (hitbox1.Shape == Shape.Rectangle && hitbox2.Shape == Shape.Rectangle)
                {
                    if (hitbox1.ScreenSpaceDrawQuad.AABB.IntersectsWith(hitbox2.ScreenSpaceDrawQuad.AABB))
                        return true;
                }
                else if (hitbox1.Shape == Shape.Complex || hitbox2.Shape == Shape.Complex)
                    foreach (SymcolContainer child1 in hitbox1.Children)
                        foreach (SymcolContainer child2 in hitbox2.Children)
                            if (child1.ScreenSpaceDrawQuad.AABB.IntersectsWith(child2.ScreenSpaceDrawQuad.AABB))
                                return true;
            }
            return false;
        }
    }

    public enum Shape
    {
        Circle,
        Rectangle,
        Complex
    }
}