int2 type for Unity

int2.cs

/////////////////////////////////////////////////////////////////////////////
// int2 is similar to Vector2, but with integers instead of floats
// Useful for various grid related things.
//
// - Swizzle operators xx/xy/yx/yy
// - Extended arithmetic operators similar to shader data types
//		A few examples:
//		int2(8,4) / int2(2,4) -> int2(4,1)
//			   16 / int2(2,4) -> int2(8,4)
//		int2(2,3) * int2(4,5) -> int2(8,15)
//
// - Any operator with an integer will result in an int2
// - Any operator with a float will result in a Vector2
// 

using UnityEngine;
using System.Collections;

[System.Serializable]
public struct int2 {

	//-----------------------------------------------------------------------
	// Data

	[SerializeField] public int x;
	[SerializeField] public int y;

	//-----------------------------------------------------------------------
	// Constructors

	public int2( int x, int y ) {
		this.x = x;
		this.y = y;
	}

	public int2( int size ) {
		this.x = size;
		this.y = size;
	}

	//-----------------------------------------------------------------------
	// Swizzling

	public int2 xx {
		get { return new int2( x, x ); }
	}

	public int2 xy {
		get { return new int2( x, y ); }
	}

	public int2 yx {
		get { return new int2( y, x ); }
	}

	public int2 yy {
		get { return new int2( y, y ); }
	}

	//-----------------------------------------------------------------------
	// Derived Data

	public int area {
		get { return Mathf.Abs(x * y); }
	}

	public int signedArea {
		get { return x * y; }
	}

	public bool isSquare {
		get { return x == y; }
	}

	public float min {
		get { return Mathf.Min( x, y ); }
	}

	public float max {
		get { return Mathf.Max( x, y ); }
	}

	public float euclideanLength {
		get { return Mathf.Sqrt( x * x + y * y ); }
	}

	public float rectilinearLength {
		get { return Mathf.Abs( x ) + Mathf.Abs( y ); }
	}

	public float chebyshevLength {
		get { return Mathf.Max( Mathf.Abs( x ), Mathf.Abs( y ) ); }
	}

	//-----------------------------------------------------------------------
	// Operators

	// Add

	public static int2 operator +( int2 a, int2 b ) {
		return new int2( a.x + b.x, a.y + b.y );
	}

	public static int2 operator +( int2 a, int v ) {
		return new int2( a.x + v, a.y + v );
	}

	public static int2 operator +( int v, int2 a ) {
		return new int2( a.x + v, a.y + v );
	}

	public static Vector2 operator +( int2 a, float v ) {
		return new Vector2( a.x + v, a.y + v );
	}

	public static Vector2 operator +( float v, int2 a ) {
		return new Vector2( a.x + v, a.y + v );
	}

	// Subtract

	public static int2 operator -( int2 a, int2 b ) {
		return new int2( a.x - b.x, a.y - b.y );
	}

	public static int2 operator -( int2 a, int v ) {
		return new int2( a.x - v, a.y - v );
	}

	public static int2 operator -( int v, int2 a ) {
		return new int2( v - a.x, v - a.y );
	}

	public static Vector2 operator -( int2 a, float v ) {
		return new Vector2( a.x - v, a.y - v );
	}

	public static Vector2 operator -( float v, int2 a ) {
		return new Vector2( v - a.x, v - a.y );
	}

	// Multiply

	public static int2 operator *( int2 a, int2 b ) {
		return new int2( a.x * b.x, a.y * b.y );
	}

	public static int2 operator *( int2 a, int v ) {
		return new int2( a.x * v, a.y * v );
	}

	public static int2 operator *( int v, int2 a ) {
		return new int2( a.x * v, a.y * v );
	}

	public static Vector2 operator *( int2 a, float v ) {
		return new Vector2( a.x * v, a.y * v );
	}

	public static Vector2 operator *( float v, int2 a ) {
		return new Vector2( a.x * v, a.y * v );
	}

	// Divide

	public static int2 operator /( int2 a, int2 b ) {
		return new int2( a.x / b.x, a.y / b.y );
	}

	public static int2 operator /( int2 a, int v ) {
		return new int2( a.x / v, a.y / v );
	}

	public static int2 operator /( int v, int2 a ) {
		return new int2( v / a.x, v / a.y );
	}

	public static Vector2 operator /( int2 a, float v ) {
		return new Vector2( a.x / v, a.y / v );
	}

	public static Vector2 operator /( float v, int2 a ) {
		return new Vector2( v / a.x, v / a.y );
	}

	// Component index access

	public int this[int i] {
		get {
			if( i == 0 )
				return x;
			else if( i == 1 )
				return y;
			else
				throw new System.IndexOutOfRangeException( "Expected an index of 0 or 1. " + i + " is out of range" );
		}
		set {
			if( i == 0 )
				x = value;
			else if( i == 1 )
				y = value;
			else
				throw new System.IndexOutOfRangeException( "Expected an index of 0 or 1. " + i + " is out of range" );
		}
	}
	
	//-----------------------------------------------------------------------
	// Static members

	public static int2 zero		= new int2( 0, 0 );
	public static int2 one		= new int2( 1, 1 );
	public static int2 right	= new int2( 1, 0 );
	public static int2 left		= new int2(-1, 0 );
	public static int2 up		= new int2( 0, 1 );
	public static int2 down		= new int2( 0,-1 );

	//-----------------------------------------------------------------------
	// Typecasting

	public static implicit operator Vector2( int2 i ) { // int2 to Vector2
		return new Vector2( i.x, i.y );
	}

	public static explicit operator int2( Vector2 v ) { // Vector2 to int2. Explicit due to precision loss
		return v.FloorToInt2(); // Floor replicates the behavior when typecasting float to int
	}

	//-----------------------------------------------------------------------
	// Static functions

	public static Vector2 Lerp( int2 a, int2 b, float t, bool extrapolate = false ) {
		t = extrapolate ? t : Mathf.Clamp01(t);
		return a * ( 1f - t ) + b * t;
	}

	public static float EuclideanDistance(int2 a, int2 b) {
		return (a - b).euclideanLength;
	}

	public static float RectilinearDistance( int2 a, int2 b ) {
		return ( a - b ).rectilinearLength;
	}

	public static float ChebyshevDistance( int2 a, int2 b ) {
		return ( a - b ).chebyshevLength;
	}

	public override string ToString() {
		return "[ "+x+" , "+y+" ]";
	}

}



// So that it integrates a bit more neatly into Unity's other classes
public static class int2extensions {

	//-----------------------------------------------------------------------
	// Rect

	// May be slightly immoral to have hidden floors in these

	public static int2 GetSize( this Rect r ) { 
		return new int2( Mathf.FloorToInt( r.width ), Mathf.FloorToInt( r.height ) );
	}

	public static int2 GetPosition( this Rect r ) {
		return new int2( Mathf.FloorToInt( r.width ), Mathf.FloorToInt( r.height ) );
	}

	//-----------------------------------------------------------------------
	// Texture

	public static void SetResolution( this Texture t, int2 resolution ) {
		t.width = resolution.x;
		t.height = resolution.y;
	}

	public static int2 GetResolution( this Texture t ) {
		return new int2(t.width,t.height);
	}

	//-----------------------------------------------------------------------
	// Vector2

	public static int2 RoundToInt2( this Vector2 v ) {
		return new int2( Mathf.RoundToInt(v.x), Mathf.RoundToInt(v.y) );
	}

	public static int2 FloorToInt2( this Vector2 v ) {
		return new int2( Mathf.FloorToInt( v.x ), Mathf.FloorToInt( v.y ) );
	}

	public static int2 CeilToInt2( this Vector2 v ) {
		return new int2( Mathf.CeilToInt( v.x ), Mathf.CeilToInt( v.y ) );
	}

}