sun.cs

Beginning C# Game Programming 的源代码

using System;
using System.Drawing;
using Microsoft.DirectX;
using Microsoft.DirectX.DirectDraw;

namespace SpaceWar {
	/// <summary>
	/// Handles the drawing of the sun
	/// </summary>
	public class Sun {
		const int NumPoints = 16;
		const int NumLines = 8;
		
		Point center;
		Point[] ends = new Point[NumPoints];

		public Sun(Point center, int radius) {
			this.center = center;

			double angle = 0;
			double inc = 3.1415926535 * 2 / NumPoints;
			for (int i = 0; i < NumPoints; i++) {
				ends[i].X = (int) Math.Round(Math.Cos(angle) * radius) + center.X;
				ends[i].Y = (int) Math.Round(Math.Sin(angle) * radius) + center.Y;
				angle += inc;
			}
		}

		public void Draw(Surface surface) {
			int dimLine = Constants.random.Next(NumLines);
			for (int i = 0; i < NumLines; i++) {
				if (i == dimLine)
					surface.ForeColor = Color.FromArgb(0,170,170);
				else
					surface.ForeColor = Color.Yellow;
				surface.DrawLine(ends[i].X, ends[i].Y,
					ends[i + NumLines].X, ends[i + NumLines].Y);
			}
		}
	}
}