[GDAL]在三维场景中显示DEM

粗糙实现了个版本

存储波段的基本信息和数据：

 namespace RGeos.Terrain
 {
    //存储波段的基本信息和数据
     public class RasterBandData
     {
         public double[] data;
         public int Columns;
         public int Rows;
         public double NoDataValue;
         public double MaxValue;
         public double MinValue;
     }
 }

RasterBandData

显示用的渲染对象：

 using System;
 using RGeos.SlimScene.Core;
 using SlimDX.Direct3D9;
 using System.Drawing;
 using SlimDX;
 using CustomVertex;
 using System.IO;

 namespace RGeos.Terrain
 {
     public class RTerrain : RenderableObject
     {
         Device device = null;
         private Bitmap bitMap = null;
         private RasterBandData DataDem = null;
         //定义行列数目
         private int Cols = , Rows = ;
         //定义像素的大小
         private float cellHeight = 10f, cellWidth = 10f;
         //纹理
         private Texture texture = null;
         //材质
         private Material material;
         //顶点缓冲变量
         private VertexBuffer vertexBuffer;
         //索引缓冲变量
         private IndexBuffer indexBuffer;
         // 顶点变量
         private CustomVertex.PositionTextured[] vertices;
         //索引号变量
         private int[] indices;

         public RTerrain(string name, RasterBandData dem, Bitmap bitmap)
             : base(name)
         {
             DataDem = dem;
             Cols = dem.Columns;
             Rows = dem.Rows;
             bitMap = bitmap;
         }

         public override void Initialize(DrawArgs drawArgs)
         {
             try
             {
                 device = drawArgs.Device;
                 LoadTexturesAndMaterials();
                 VertexDeclaration();
                 IndicesDeclaration();//定义索引缓冲
                 isInitialized = true;
             }
             catch (Exception ex)
             {
                 isInitialized = false;
                 throw ex;
             }

         }
         //导入贴图和材质
         private void LoadTexturesAndMaterials()
         {
             material = new Material();
             material.Diffuse = Color.White;
             material.Specular = Color.LightGray;
             material.Power = 15.0F;
             device.Material = material;
             System.IO.MemoryStream memory = new System.IO.MemoryStream();
             bitMap.Save(memory, System.Drawing.Imaging.ImageFormat.Bmp);
             memory.Seek(, SeekOrigin.Begin);
             texture = Texture.FromStream(device, memory);
         }

         public override void Update(DrawArgs drawArgs)
         {
             if (!isInitialized && isOn)
                 Initialize(drawArgs);
         }
         //定义顶点
         private void VertexDeclaration()
         {
             vertexBuffer = new VertexBuffer(device, Cols * Rows * CustomVertex.PositionTextured.SizeBytes, Usage.Dynamic | Usage.WriteOnly, CustomVertex.PositionTextured.Format, Pool.Default);
             DataStream vs = vertexBuffer.Lock(, Cols * Rows * CustomVertex.PositionTextured.SizeBytes, LockFlags.None);
             vertices = new CustomVertex.PositionTextured[Cols * Rows];//定义顶点 

             for (int i = ; i < Rows; i++)
             {
                 for (int j = ; j < Cols; j++)
                 {
                     //Color color = bitMap.GetPixel((int)(j * cellWidth), (int)(i * cellHeight));
                     float height = (float)DataDem.data[i * Cols + j];
                     if (height == DataDem.NoDataValue)
                     {
                         height = ;
                     }
                     vertices[j + i * Cols].Position = new Vector3(j * cellWidth, height, -i * cellHeight);
                     vertices[j + i * Cols].Tu = (float)j / (Cols - );
                     vertices[j + i * Cols].Tv = (float)i / (Rows - );
                 }
             }
             vs.WriteRange(vertices);
             vertexBuffer.Unlock();
             vs.Dispose();
         }
         //定义索引
         private void IndicesDeclaration()
         {
             indexBuffer = new IndexBuffer(device,  *  * (Cols - ) * (Rows - ), Usage.WriteOnly, Pool.Default, true);
             DataStream ds = indexBuffer.Lock(,  *  * (Cols - ) * (Rows - ), LockFlags.None);
             indices = new int[ * (Cols - ) * (Rows - )];
             int index = ;
             for (int i = ; i < Rows - ; i++)
             {
                 for (int j = ; j < Cols - ; j++)
                 {
                     indices[index] = j + i * (Cols);
                     indices[index + ] = j + (i + ) * Cols;
                     indices[index + ] = j + i * Cols + ;
                     indices[index + ] = j + i * Cols + ;
                     indices[index + ] = j + (i + ) * Cols;
                     indices[index + ] = j + (i + ) * Cols + ;
                     index += ;
                 }
             }
             ds.WriteRange(indices);
             indexBuffer.Unlock();
             ds.Dispose();
         }

         public override void Render(DrawArgs drawArgs)
         {
             if (!isInitialized || !isOn)
                 return;
             VertexFormat curFormat = drawArgs.Device.VertexFormat;
             int curZEnable = drawArgs.Device.GetRenderState(RenderState.ZEnable);
             int curLighting = drawArgs.Device.GetRenderState(RenderState.Lighting);
             int curCull = drawArgs.Device.GetRenderState(RenderState.CullMode);
             int curAlphaBlendEnable = drawArgs.Device.GetRenderState(RenderState.AlphaBlendEnable);
             int curDepthBias = drawArgs.Device.GetRenderState(RenderState.DepthBias);
             int curColorOperation = drawArgs.Device.GetTextureStageState(, TextureStage.ColorOperation);
             try
             {
                 drawArgs.Device.SetRenderState(RenderState.Lighting, false);
              drawArgs.Device.VertexFormat = PositionTextured.Format;
                 drawArgs.Device.SetRenderState(RenderState.ZEnable, true);
                 drawArgs.Device.SetRenderState(RenderState.CullMode, Cull.None);
                 drawArgs.Device.SetTextureStageState(, TextureStage.ColorOperation, TextureOperation.Modulate);
                 drawArgs.Device.SetTextureStageState(, TextureStage.ColorArg1, TextureArgument.Texture);
                 drawArgs.Device.SetTextureStageState(, TextureStage.ColorArg2, TextureArgument.Diffuse);
                 drawArgs.Device.SetTextureStageState(, TextureStage.AlphaOperation, TextureOperation.Disable);
                 device.SetTexture(, texture);//设置贴图 

                 device.SetStreamSource(, vertexBuffer, , PositionTextured.SizeBytes);
                 device.Indices = indexBuffer;
                 device.DrawIndexedPrimitives(PrimitiveType.TriangleList, , , (Cols * Rows), , indices.Length / );
             }
             catch (Exception ex)
             {
             }
             finally
             {
                 drawArgs.Device.VertexFormat = curFormat;
                 drawArgs.Device.SetRenderState(RenderState.ZEnable, curZEnable);
                 drawArgs.Device.SetRenderState(RenderState.Lighting, curLighting);
                 drawArgs.Device.SetRenderState(RenderState.CullMode, curCull);
                 drawArgs.Device.SetRenderState(RenderState.AlphaBlendEnable, curAlphaBlendEnable);
                 drawArgs.Device.SetRenderState(RenderState.DepthBias, curDepthBias);
                 drawArgs.Device.SetTextureStageState(, TextureStage.ColorOperation, curColorOperation);
             }
         }

         public override void Dispose()
         {
             if (vertexBuffer != null)
             {
                 vertexBuffer.Dispose();
                 vertexBuffer = null;
                 texture = null;
                 vertices = null;
             }
             if (indexBuffer != null)
             {
                 indexBuffer.Dispose();
                 indexBuffer = null;
                 indices = null;
             }
         }

         public override bool PerformSelectionAction(DrawArgs drawArgs)
         {
             throw new NotImplementedException();
         }
     }
 }

RTerrain

调用方法：

   OpenFileDialog dlg = new OpenFileDialog();
             dlg.Title = "";
             dlg.Filter = "Img(*.img)|*.img";
             if (dlg.ShowDialog() == DialogResult.OK)
             {
                 string file = dlg.FileName;
                 string NameOf = System.IO.Path.GetFileNameWithoutExtension(file);
                 DemHelper dem = new DemHelper();
                 dem.Start();
                 dem.Read(file);
                 RasterBandData bandata = dem.ReadDate(, );
                 Bitmap bitmap = dem.MakeGrayScale(, );
                 Vector3 position = new Vector3(-100f, 0f, 100f);
                 //SimpleRasterShow simRaster = new SimpleRasterShow(NameOf, position, bitmap.Width, bitmap.Height);
                 //simRaster.IsOn = true;
                 //simRaster.RenderPriority = RenderPriority.Custom;
                 //simRaster.bitmap = bitmap;
                 //mSceneControl.CurrentWorld.RenderableObjects.ChildObjects.Add(simRaster);
                 RTerrain terrain = new RTerrain(NameOf, bandata, bitmap);
                 terrain.IsOn = true;
                 mSceneControl.CurrentWorld.RenderableObjects.ChildObjects.Add(terrain);
             }