Files
OpenRA/OpenRA.Mods.Common/Util.cs
2016-01-19 23:35:18 +00:00

122 lines
3.0 KiB
C#

#region Copyright & License Information
/*
* Copyright 2007-2015 The OpenRA Developers (see AUTHORS)
* This file is part of OpenRA, which is free software. It is made
* available to you under the terms of the GNU General Public License
* as published by the Free Software Foundation. For more information,
* see COPYING.
*/
#endregion
using System;
using System.Collections.Generic;
using System.Linq;
using OpenRA.Support;
using OpenRA.Traits;
namespace OpenRA.Mods.Common
{
public static class Util
{
public static int TickFacing(int facing, int desiredFacing, int rot)
{
var leftTurn = (facing - desiredFacing) & 0xFF;
var rightTurn = (desiredFacing - facing) & 0xFF;
if (Math.Min(leftTurn, rightTurn) < rot)
return desiredFacing & 0xFF;
else if (rightTurn < leftTurn)
return (facing + rot) & 0xFF;
else
return (facing - rot) & 0xFF;
}
public static int GetNearestFacing(int facing, int desiredFacing)
{
var turn = desiredFacing - facing;
if (turn > 128)
turn -= 256;
if (turn < -128)
turn += 256;
return facing + turn;
}
public static int QuantizeFacing(int facing, int numFrames)
{
var step = 256 / numFrames;
var a = (facing + step / 2) & 0xff;
return a / step;
}
public static WPos BetweenCells(World w, CPos from, CPos to)
{
return WPos.Lerp(w.Map.CenterOfCell(from), w.Map.CenterOfCell(to), 1, 2);
}
/* pretty crap */
public static IEnumerable<T> Shuffle<T>(this IEnumerable<T> ts, MersenneTwister random)
{
var items = ts.ToList();
while (items.Count > 0)
{
var t = items.Random(random);
yield return t;
items.Remove(t);
}
}
static IEnumerable<CPos> Neighbours(CPos c, bool allowDiagonal)
{
yield return c;
yield return new CPos(c.X - 1, c.Y);
yield return new CPos(c.X + 1, c.Y);
yield return new CPos(c.X, c.Y - 1);
yield return new CPos(c.X, c.Y + 1);
if (allowDiagonal)
{
yield return new CPos(c.X - 1, c.Y - 1);
yield return new CPos(c.X + 1, c.Y - 1);
yield return new CPos(c.X - 1, c.Y + 1);
yield return new CPos(c.X + 1, c.Y + 1);
}
}
public static IEnumerable<CPos> ExpandFootprint(IEnumerable<CPos> cells, bool allowDiagonal)
{
return cells.SelectMany(c => Neighbours(c, allowDiagonal)).Distinct();
}
public static IEnumerable<CPos> AdjacentCells(World w, Target target)
{
var cells = target.Positions.Select(p => w.Map.CellContaining(p)).Distinct();
return ExpandFootprint(cells, true);
}
public static int ApplyPercentageModifiers(int number, IEnumerable<int> percentages)
{
// See the comments of PR#6079 for a faster algorithm if this becomes a performance bottleneck
var a = (decimal)number;
foreach (var p in percentages)
a *= p / 100m;
return (int)a;
}
public static IEnumerable<CPos> RandomWalk(CPos p, MersenneTwister r)
{
for (;;)
{
var dx = r.Next(-1, 2);
var dy = r.Next(-1, 2);
if (dx == 0 && dy == 0)
continue;
p += new CVec(dx, dy);
yield return p;
}
}
}
}