latlon.cs

功能：基于windows mobile 的地图查看器。使用vs2005开发

using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;

using Microsoft.WindowsMobile.DirectX;
using Microsoft.WindowsMobile.DirectX.Direct3D;

using WorldWindow;

namespace cfWorldWind
{
	class LatLon
	{
		Material latLonMaterial;

		public LatLon()
		{

		}

		public class LatLonLineList
		{
			public VertexBuffer vertexBuffer;
			public int numberOfPrimitives;
		}

		//public void DrawLatLonLines(Device device, float latitude, float longitude, float altitude, float viewRange)
		public List<LatLonLineList> InitializeLatLonLines(Device device, int dLat)
		{
			latLonMaterial = new Material();
			latLonMaterial.Diffuse = Color.Gray;
			latLonMaterial.Ambient = Color.Gray;

			List<LatLonLineList> alLatLonBuffers = new List<LatLonLineList>();

			//this calculation happens during init now
			//int dLat = 10;
			//double vr = drawArgs.WorldCamera.ViewRange.Radians * 0.75;
			//double vr = viewRange * .75;
			//if (vr < 0.1)
			//	dLat = 1;
			//else if (vr < 0.6)
			//	dLat = 2;
			//else if (vr < 1.1)
			//	dLat = 5;

			int dLon = dLat;

			//if (drawArgs.WorldCamera.Latitude.Radians + vr / 2 > Math.PI / 2 || drawArgs.WorldCamera.Latitude.Radians - vr / 2 < -Math.PI / 2)
			//if (MathEngine.DegreesToRadians(latitude) + vr / 2 > Math.PI / 2 || MathEngine.DegreesToRadians(latitude) - vr / 2 < -Math.PI / 2)
			//{
			// Pole visible, 10 degree longitude spacing forced
			//	dLon = 10;
			//dLat = 10;
			//}

			//int minLon = dLon >= 10 ? -180 : (int)drawArgs.WorldCamera.Longitude.Degrees / dLon * dLon - 18 * dLon;
			//int maxLon = dLon >= 10 ? 180 : (int)drawArgs.WorldCamera.Longitude.Degrees / dLon * dLon + 18 * dLon;
			//int minLat = (int)drawArgs.WorldCamera.Latitude.Degrees / dLat * dLat - 9 * dLat;
			//int maxLat = (int)drawArgs.WorldCamera.Latitude.Degrees / dLat * dLat + 9 * dLat;

			//this calculation doesnt draw all the lines
			//int minLon = dLon >= 10 ? -180 : (int)longitude / dLon * dLon - 18 * dLon;
			//int maxLon = dLon >= 10 ? 180 : (int)longitude / dLon * dLon + 18 * dLon;
			//int minLat = (int)latitude / dLat * dLat - 9 * dLat;
			//int maxLat = (int)latitude / dLat * dLat + 9 * dLat;
			//if (maxLat - minLat >= 180 || dLon == 10)
			//{
			//	minLat = -90;
			//	maxLat = 90;
			//}
			int minLon = -180;
			int maxLon = 180;
			int minLat = -90;
			int maxLat = 90;


			double radius = Settings.Radius;
			//if (drawArgs.device.RenderState.ZBufferEnable)
			if (device.RenderState.ZBufferEnable)
			{
				double bRadius = radius * 1.01f;
				//double nRadius = radius + 0.015f * drawArgs.WorldCamera.Altitude;
				double nRadius = radius + 0.015f * Settings.Radius;
				radius = nRadius < bRadius ? nRadius : bRadius;
			}

			//drawArgs.device.TextureState[0].ColorOperation = TextureOperation.Disable;
			//drawArgs.device.VertexFormat = CustomVertex.PositionColored.Format;
			//ColorOperation defaults to Modulate
			//device.TextureState[0].ColorOperation = TextureOperation.Disable;
			//device.VertexFormat = CustomVertex.PositionColored.Format;

			System.Drawing.Font f = new System.Drawing.Font("Arial", 8F, System.Drawing.FontStyle.Regular);
			Microsoft.WindowsMobile.DirectX.Direct3D.Font dispFont = new Microsoft.WindowsMobile.DirectX.Direct3D.Font(device, f);

			// Draw latitude lines
			for (int i = minLon; i < maxLon; i = i + dLon)
			{
				int itr = 0;
				int numPoints = (maxLat - minLat) / dLat + 1;
				CustomVertex.PositionColored[] curLine = new CustomVertex.PositionColored[numPoints];

				for (int j = minLat; j <= maxLat; j = j + dLat)
				{
					Vector3 pos = MathEngine.SphericalToCartesian((float)j, (float)i, radius);
					curLine[itr].X = pos.X;
					curLine[itr].Y = pos.Y;
					curLine[itr].Z = pos.Z;
					//curLine[itr].Color = World.Settings.latLonLinesColor;
					curLine[itr].Color = Color.Gray.ToArgb();
					itr++;
				}

				//drawArgs.device.DrawUserPrimitives(PrimitiveType.LineStrip, numPoints - 1, curLine);
				VertexBuffer vb = new VertexBuffer(typeof(CustomVertex.PositionColored), numPoints, device, 0, CustomVertex.PositionColored.Format, Pool.SystemMemory);
				GraphicsStream stm = vb.Lock(0, 0, 0);
				stm.Write(curLine);
				vb.Unlock();
				//device.SetStreamSource(0, vb, 0);
				//device.DrawPrimitives(PrimitiveType.LineStrip, 0, numPoints-1);
				LatLonLineList llll = new LatLonLineList();
				llll.vertexBuffer = vb;
				llll.numberOfPrimitives = numPoints - 1;
				alLatLonBuffers.Add(llll);

				/*
				// Draw longitude label
				//float lat = (float)(drawArgs.WorldCamera.Latitude + drawArgs.WorldCamera.ViewRange * 0.15).Degrees;
				float lat = (float)(MathEngine.RadiansToDegrees(MathEngine.DegreesToRadians(latitude) + viewRange * 0.15));
				if (lat > 70)
					lat = 70;
				Vector3 v = MathEngine.SphericalToCartesian(lat, (float)i, radius);
				//if (drawArgs.WorldCamera.ViewFrustum.ContainsPoint(v))
				//{
					string s = "";
					if (i > 0)
						s = i.ToString() + "E";
					else if (i < 0)
						s = Math.Abs(i).ToString() + "W";
					else
						s = i.ToString();

					//v.Project(drawArgs.device.Viewport, drawArgs.device.Transform.Projection, drawArgs.device.Transform.View, drawArgs.device.Transform.World);
					//drawArgs.defaultDrawingFont.DrawText(null, s, new System.Drawing.Rectangle((int)v.X + 2, (int)v.Y, drawArgs.screenWidth, drawArgs.screenHeight), DrawTextFormat.NoClip, World.Settings.latLonLinesColor);
					v.Project(device.Viewport, device.Transform.Projection, device.Transform.View, device.Transform.World);
					dispFont.DrawText(null, s, new System.Drawing.Rectangle((int)v.X + 2, (int)v.Y, device.Viewport.Width, device.Viewport.Height), DrawTextFormat.NoClip, Color.Gray);
				//}
				 */
			}

			// Draw longitude lines
			for (int iLatitude = minLat; iLatitude <= maxLat; iLatitude = iLatitude + dLat)
			{
				/*
				// Draw latitude label
				//float lon = (float)(drawArgs.WorldCamera.Longitude - drawArgs.WorldCamera.ViewRange * 0.25f).Degrees;
				float lon = (float)(MathEngine.RadiansToDegrees(MathEngine.DegreesToRadians(longitude) - viewRange * 0.25f));
				Vector3 v = MathEngine.SphericalToCartesian((float)iLatitude, lon, radius);
				//if (drawArgs.WorldCamera.ViewFrustum.ContainsPoint(v))
				//{
					v.Project(device.Viewport, device.Transform.Projection, device.Transform.View, device.Transform.World);
					int latLabel = iLatitude;
					if (latLabel > 90)
						latLabel = 180 - latLabel;
					else if (latLabel < -90)
						latLabel = -180 - latLabel;
					string s = Math.Abs(latLabel).ToString();
					if (latLabel > 0)
						s += "N";
					else if (latLabel < 0)
						s += "S";
					//drawArgs.defaultDrawingFont.DrawText(null, s, new System.Drawing.Rectangle((int)v.X, (int)v.Y, drawArgs.screenWidth, drawArgs.screenHeight), DrawTextFormat.NoClip, World.Settings.latLonLinesColor);
					dispFont.DrawText(null, s, new System.Drawing.Rectangle((int)v.X, (int)v.Y, device.Viewport.Width, device.Viewport.Height), DrawTextFormat.NoClip, Color.Gray);
				//}
				 */

				int numPoints = (maxLon - minLon) / dLon + 1;
				int itr = 0;
				CustomVertex.PositionColored[] curLine = new CustomVertex.PositionColored[numPoints];
				for (int j = minLon; j <= maxLon; j = j + dLon)
				{
					Vector3 pos = MathEngine.SphericalToCartesian((float)iLatitude, (float)j, radius);
					curLine[itr].X = pos.X;
					curLine[itr].Y = pos.Y;
					curLine[itr].Z = pos.Z;

					if (iLatitude == 0)
					{
						curLine[itr].Color = Color.Red.ToArgb(); //TODO this color is ignored
					}
					else
					{
						curLine[itr].Color = Color.Gray.ToArgb(); //TODO this color is ignored
					}

					itr++;
				}
				//drawArgs.device.DrawUserPrimitives(PrimitiveType.LineStrip, numPoints - 1, curLine);
				VertexBuffer vb = new VertexBuffer(typeof(CustomVertex.PositionColored), numPoints, device, 0, CustomVertex.PositionColored.Format, Pool.SystemMemory);
				GraphicsStream stm = vb.Lock(0, 0, 0);
				stm.Write(curLine);
				vb.Unlock();
				//device.SetStreamSource(0, vb, 0);
				//device.DrawPrimitives(PrimitiveType.LineStrip, 0, numPoints - 1);
				LatLonLineList llll = new LatLonLineList();
				llll.vertexBuffer = vb;
				llll.numberOfPrimitives = numPoints - 1;
				alLatLonBuffers.Add(llll);
			}
			return alLatLonBuffers;
		}

		public void RenderLatLonLines(Device device, List<LatLonLineList> alLatLonBuffers)
		{
			//WTF
			//the default value is Modules, so reset that at the end
			//device.TextureState[0].ColorOperation = TextureOperation.Disable;

			//TODO draw labels on lines?
			//TODO viewFrustum to remove labels?
			if (alLatLonBuffers != null)
			{
				//TODO how am i supposed to do this instead?
				device.Material = latLonMaterial;
				device.SetTexture(0, null);

				foreach (LatLonLineList llll in alLatLonBuffers)
				{
					device.SetStreamSource(0, llll.vertexBuffer, 0);
					device.DrawPrimitives(PrimitiveType.LineStrip, 0, llll.numberOfPrimitives);
				}
			}

			//device.TextureState[0].ColorOperation = TextureOperation.Modulate;
		}

		public void Dispose(List<LatLonLineList> latLonList)
		{
			if (latLonList != null)
			{
				foreach (LatLonLineList llll in latLonList)
				{
					llll.vertexBuffer.Dispose();
					llll.vertexBuffer = null;
				}
				latLonList.Clear();
				latLonList = null;
			}
		}
	}
}