ArcGIS Engine渲染

符号化之Renderer( 渲染)体系

ArcGIS Engine9.3对GIS数据的符号化分为矢量数据渲染和栅格数据渲染两大类。接下来分别介绍FeatureRender和RasterRender。

1.FeatureRender对象
    FeatureRenderer是一个抽象类，它有15个子类负责进行不同类型的着色运算。它们都实现了IFeatureRenderer接口，这个接口定义了进行要素图层符号化的公共属性和方法。
    可以通过IGeoFeatureLayer::Renderer属性获得一个要素图层的符号化对象

表四

常用的要素符号化类型主要有以下6种类型，如图13所示：
    

图13

由于篇幅有限不再对每一种符号化类型的使用进行讲解，在后边的实例中将为读者演示如何进行唯一值符号化。

2.RasterRender对象
      RasterRender是一个抽象类，它有15个子类负责进行不同类型的着色运算。它们都实现了IRasterRender接口，这个接口定义了栅格图层符号化的公共属性和方法。可以通过IRasterLayer::Renderer属性获得一个栅格图层的符号化对象。

栅格符号化类型结构图如图14所示：

图14

以下代码片段是对一个RasterLayer进行RasterStretchColorRampRenderer符号化操作：

///

/// StretchColorRamp符号化RasterLayer

///

///RasterLayer

publicvoid SetStretchColorRampRenderer(IRasterLayer pRasterLayer)

{

try

{

//创建RasterStretchColorRampRendererClass对象

IRasterStretchColorRampRenderer pRStretchRender=newRasterStretchColorRampRendererClass();

//QI到IRasterRenderer

IRasterRenderer pRasterRender=pRStretchRenderas IRasterRenderer;

pRasterRender.Raster = pRasterLayer asIRaster;

pRasterRender.Update();

//创建两个起始颜色

IRgbColor pFromRgbColor =new RgbColorClass();

pFromRgbColor.Red = 255;

IRgbColor pToRgbColor =new RgbColorClass();

pToRgbColor.Blue = 255;

//创建起止颜色带

IAlgorithmicColorRamp pAlgorithmicColorRamp =newAlgorithmicColorRampClass();

pAlgorithmicColorRamp.Size = 255;

pAlgorithmicColorRamp.FromColor = pFromRgbColor asIColor;

pAlgorithmicColorRamp.ToColor = pToRgbColor asIColor;

bool btrue=true;

pAlgorithmicColorRamp.CreateRamp(out btrue);

//选择拉伸颜色带符号化的波段

pRStretchRender.BandIndex = 0;

//设置拉伸颜色带符号化所采用的颜色带

pRStretchRender.ColorRamp = pAlgorithmicColorRamp asIColorRamp;

pRasterRender.Update();

//符号化RasterLayer

pRasterLayer.Renderer = pRasterRender;

}

catch(Exception Err)

{

MessageBox.Show(Err.Message,"提示",MessageBoxButtons.OK,MessageBoxIcon.Information);

}

}

AE之分级颜色专题图渲染

参考代码1：

private void 分级渲染ToolStripMenuItem_Click(object sender, EventArgs e)

{

//值分级

IBasicHistogram pBasicHis = new BasicTableHistogramClass();

ITableHistogram pTabHis = (ITableHistogram)pBasicHis;

pTabHis.Field = "w1";

ITable pTab = (ITable)axMapControl1.get_Layer(0);

pTabHis.Table = pTab;

object doubleArrVal, longArrFreq;

pBasicHis.GetHistogram(out doubleArrVal, out longArrFreq);

IClassifyGEN pClassify = new EqualIntervalClass();  //NaturalBreaksClass

int nDes = 5;

pClassify.Classify(doubleArrVal, longArrFreq, ref nDes);

object classes = pClassify.ClassBreaks;

System.Array pArr = (System.Array)classes;

//算法梯度颜色

IAlgorithmicColorRamp pAlgoColorRamp = new AlgorithmicColorRampClass();

pAlgoColorRamp.Size = pArr.Length;

IRgbColor pFromColor = new RgbColorClass(), pToColor = new RgbColorClass();

pFromColor.Red = 0;

pFromColor.Green = 255;

pFromColor.Blue = 0;

pToColor.Red = 255;

pToColor.Green = 0;

pToColor.Blue = 255;

pAlgoColorRamp.FromColor = pFromColor;

pAlgoColorRamp.ToColor = pToColor;

bool ok = true;

pAlgoColorRamp.CreateRamp(out ok);

//颜色梯度结束

IClassBreaksRenderer pRender = new ClassBreaksRendererClass();

pRender.BreakCount = pArr.Length;

pRender.Field = "w1";

ISimpleFillSymbol pSym;

for (int i = 0; i < pArr.Length; i++)

{

pRender.set_Break(i, (double)pArr.GetValue(i));

pSym = new SimpleFillSymbolClass();

pSym.Color = pAlgoColorRamp.get_Color(i);

pRender.set_Symbol(i, (ISymbol)pSym);

}

IGeoFeatureLayer pGeoLyr = (IGeoFeatureLayer)axMapControl1.get_Layer(0);

pGeoLyr.Renderer = (IFeatureRenderer)pRender;

axMapControl1.Refresh();

axTOCControl1.Update();

}

参考代码2：

private void 分层设色ToolStripMenuItem_Click(object sender, EventArgs e)

{

//获取当前图层 ，并把它设置成IGeoFeatureLayer的实例

IMap pMap = axMapControl1.Map;

ILayer pLayer = pMap.get_Layer(0) as IFeatureLayer;

IFeatureLayer pFeatureLayer = pLayer as IFeatureLayer;

IGeoFeatureLayer pGeoFeatureLayer = pLayer as IGeoFeatureLayer;

//获取图层上的feature

IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;

IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, false);

IFeature pFeature = pFeatureCursor.NextFeature();

//

IFeatureRenderer PR=pGeoFeatureLayer.Renderer;

//JoinData("县级区域", "DZGB", "sectioncode");   //join外部表

// int DC ;

int  desiredClasses = 5;

string fieldName = "w1";

int classesCount;

double[] classes;

string strOutput = "";

bool ok;

object dataFrequency;

object dataValues;

ITable pTable ;

//IClassify pClassify;

EqualIntervalClass pClassify;

//IBasicHistogram pTableHistogram = new BasicTableHistogramClass();

//IHistogram pTableHistogram = new BasicTableHistogramClass();

ITableHistogram pTableHistogram = new BasicTableHistogramClass() as ITableHistogram;

IBasicHistogram pHistogram;

IClassBreaksRenderer pClassBreaksRenderer;

IHsvColor pFromColor;

IHsvColor pToColor;

IAlgorithmicColorRamp pAlgorithmicColorRamp;

IEnumColors pEnumColors;

IColor pColor;

ISimpleFillSymbol pSimpleFillSymbol;

pLayer = (IFeatureLayer)axMapControl1.get_Layer(0);

pGeoFeatureLayer = (IGeoFeatureLayer)pLayer;

pTable = (ITable)pGeoFeatureLayer;

pHistogram = (IBasicHistogram)pTableHistogram;

// Get values and frequencies for the field

pTableHistogram.Field = fieldName;

pTableHistogram.Table = pTable;

pHistogram.GetHistogram(out dataValues, out dataFrequency);

// Put values and frequencies into an Equal Interval Classify Object

pClassify = new EqualIntervalClass();

//pClassify = new NaturalBreaksClass();

pClassify.SetHistogramData(dataValues, dataFrequency);

pClassify.Classify(dataValues, dataFrequency, ref desiredClasses);

//pClassify.Classify(ref desiredClasses);

classes = (double[])pClassify.ClassBreaks;

classesCount = classes.Length;

// Initialise a new Class Breaks renderer

// Supply the number of Class Breaks and the field to perform. the class breaks on

pClassBreaksRenderer = new ClassBreaksRendererClass();

pClassBreaksRenderer.Field = fieldName;

pClassBreaksRenderer.BreakCount = classesCount;

pClassBreaksRenderer.SortClassesAscending = true;

// Use algorithmic color ramp to generate an range of colors between YELLOW to RED

// Initial color: YELLOW

pFromColor = new HsvColorClass();

pFromColor.Hue = 60;

pFromColor.Saturation = 100;

pFromColor.Value = 96;

// Final color: RED

pToColor = new HsvColorClass();

pToColor.Hue = 0;

pToColor.Saturation = 100;

pToColor.Value = 96;

// Set up HSV Color ramp to span from YELLOW to RED

pAlgorithmicColorRamp = new AlgorithmicColorRampClass();

pAlgorithmicColorRamp.Algorithm = esriColorRampAlgorithm.esriHSVAlgorithm;

pAlgorithmicColorRamp.FromColor = pFromColor;

pAlgorithmicColorRamp.ToColor = pToColor;

pAlgorithmicColorRamp.Size = classesCount;

pAlgorithmicColorRamp.CreateRamp(out ok);

pEnumColors = pAlgorithmicColorRamp.Colors;

for (int index = 0; index < classesCount - 1; index++)

{

pColor = pEnumColors.Next();

pSimpleFillSymbol = new SimpleFillSymbolClass();

pSimpleFillSymbol.Color = pColor;

pSimpleFillSymbol.Style = esriSimpleFillStyle.esriSFSSolid;

pClassBreaksRenderer.set_Symbol(index, (ISymbol)pSimpleFillSymbol);

pClassBreaksRenderer.set_Break(index, classes[index + 1]);

// Store each break value for user output

strOutput += "-" + classes[index + 1] + "\n";

}

pGeoFeatureLayer.Renderer = (IFeatureRenderer)pClassBreaksRenderer;

//this.axMapControl1.Refresh();

/////////////////////////////////////////////////////////////////////////////////////////

//////////////////////////////////////////////////////////////////////////////////////////

//get the custom property from which is supposed to be the layer to be saved

object customProperty = null;

//IMapControl3 mapControl = null;

customProperty = axMapControl1.CustomProperty;

//ask the user to set a name for the new layer file

SaveFileDialog saveFileDialog = new SaveFileDialog();

saveFileDialog.Filter = "Layer File|*.lyr|All Files|*.*";

saveFileDialog.Title = "生成专题图";

saveFileDialog.RestoreDirectory = true;

saveFileDialog.FileName = System.IO.Path.Combine(saveFileDialog.InitialDirectory, pGeoFeatureLayer.Name + ".lyr");

//get the layer name from the user

DialogResult dr = saveFileDialog.ShowDialog();

if (saveFileDialog.FileName != "" && dr == DialogResult.OK)

{

if (System.IO.File.Exists(saveFileDialog.FileName))

{

//try to delete the existing file

System.IO.File.Delete(saveFileDialog.FileName);

}

//create a new LayerFile instance

ILayerFile layerFile = new LayerFileClass();

//create a new layer file

layerFile.New(saveFileDialog.FileName);

//attach the layer file with the actual layer

layerFile.ReplaceContents((ILayer)pGeoFeatureLayer);

//save the layer file

layerFile.Save();

//ask the user whether he‘d like to add the layer to the map

if (DialogResult.Yes == MessageBox.Show("Would you like to add the layer to the map?", "Message", MessageBoxButtons.YesNo,MessageBoxIcon.Question))

{

axMapControl1.AddLayerFromFile(saveFileDialog.FileName, 0);

}

}

IActiveView pActiveView = axMapControl1.Map as IActiveView;

pActiveView.Refresh();

axTOCControl1.Update();

}

参考代码3：

private void 等级专题图ToolStripMenuItem_Click(object sender, EventArgs e)

{

// 获取当前图层，并把它设置成IGeoFeatureLayer的实例

ILayer pLayer = axMapControl1.get_Layer(0);

IFeatureLayer pFeatLayer = (IFeatureLayer)pLayer;

IGeoFeatureLayer pGeoFeatLayer = (IGeoFeatureLayer)pLayer;

IFeatureClass pFeatClass = pFeatLayer.FeatureClass;

// We‘re going to retrieve frequency data from a population

// field and then clasify this data

ITable pTable = (ITable)pFeatClass;

IBasicHistogram pBasicHistogram = new BasicTableHistogramClass();

ITableHistogram pTableHistogram = (ITableHistogram)pBasicHistogram;

// Get values and frequencies for the population field into a table histogram object

string fieldName = "w1";

pTableHistogram.Field = fieldName;

pTableHistogram.Table = pTable;

object dataValues;

object dataFrequency;

pBasicHistogram.GetHistogram(out dataValues, out dataFrequency);

IClassifyGEN pClassifyGEN = new QuantileClass();

int numClass = 3;

pClassifyGEN.Classify(dataValues, dataFrequency, ref numClass);

double[] classes = (double[])pClassifyGEN.ClassBreaks;

long classesCount = long.Parse(classes.GetUpperBound(0).ToString());

// Initialize a new class breaks renderer and supply the number of class breaks

// and the field to perform the class breaks on

IClassBreaksRenderer pClassBreaksRenderer = new ClassBreaksRendererClass();

pClassBreaksRenderer.Field = fieldName;

pClassBreaksRenderer.MinimumBreak = classes[0];

pClassBreaksRenderer.SortClassesAscending = true;

// 设置着色对象的分级数目

pClassBreaksRenderer.BreakCount = int.Parse(classesCount.ToString());

// 创建并设置随机色谱

IAlgorithmicColorRamp pAlgorithmicColorRamp = new AlgorithmicColorRampClass();

pAlgorithmicColorRamp.Algorithm = esriColorRampAlgorithm.esriCIELabAlgorithm;

IEnumColors pEnumColors;

IRgbColor pColor1 = new RgbColorClass();

IRgbColor pColor2 = new RgbColorClass();

pColor1.Red = 255;

pColor1.Green = 210;

pColor1.Blue = 210;

pColor2.Red = 190;

pColor2.Green = 0;

pColor2.Blue = 170;

pAlgorithmicColorRamp.FromColor = pColor1;

pAlgorithmicColorRamp.ToColor = pColor2;

pAlgorithmicColorRamp.Size = numClass;

bool ok = true;

pAlgorithmicColorRamp.CreateRamp(out ok);

pEnumColors = pAlgorithmicColorRamp.Colors;

pEnumColors.Reset();

IClassBreaksUIProperties pUIProperties = (IClassBreaksUIProperties)pClassBreaksRenderer;

pUIProperties.ColorRamp = "Custom";

ISimpleFillSymbol pSimpleMarkerSymbol = new SimpleFillSymbolClass();

IColor pColor;

int[] colors = new int[numClass];

// be careful, indices are different for the different lists

for (int breakIndex = 0; breakIndex < classesCount; breakIndex++)

{

pClassBreaksRenderer.set_Label(breakIndex, classes[breakIndex] + "-" + classes[breakIndex + 1]);

pUIProperties.set_LowBreak(breakIndex, classes[breakIndex]);

ISimpleFillSymbol pFillSymbol = new SimpleFillSymbolClass();

pColor = pEnumColors.Next();

pFillSymbol.Color = pColor;

colors[breakIndex] = pColor.RGB;

pClassBreaksRenderer.set_Symbol(breakIndex, (ISymbol)pFillSymbol);

pClassBreaksRenderer.set_Break(breakIndex, classes[breakIndex + 1]);

}

// 将等级图渲染对象与渲染图层挂钩

pGeoFeatLayer.Renderer = (IFeatureRenderer)pClassBreaksRenderer;

axMapControl1.ActiveView.Refresh();

axTOCControl1.Update();

}

参考代码4：

private void 等级图ToolStripMenuItem_Click(object sender, EventArgs e)

{

//获取当前图层 ，并把它设置成IGeoFeatureLayer的实例

IMap pMap = axMapControl1.Map;

ILayer pLayer = pMap.get_Layer(0) as IFeatureLayer;

IFeatureLayer pFeatureLayer = pLayer as IFeatureLayer;

IGeoFeatureLayer pGeoFeatureLayer = pLayer as IGeoFeatureLayer;

//获取图层上的feature

IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;

IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, false);

IFeature pFeature = pFeatureCursor.NextFeature();

//////////////////////////////////////////////////////////////////////

//定义所需的接口对象和相关变量

IClassBreaksUIProperties pUIProperties;

object dataValues;

object dataFrequency;

//double[] cb;

int breakIndex;

long ClassesCount;

int numClass;

numClass = 10;

double[] Classes;

//////////////////////////////////////////////////////////////////////

ITable pTable;

pTable = pFeatureClass as ITable;

IBasicHistogram pBasicHist = new BasicTableHistogramClass();

ITableHistogram pTableHist;

pTableHist = (ITableHistogram)pBasicHist;

//Get values and frequencies for the population field into a table histogram object

pTableHist.Field = "w1";

pTableHist.Table = pTable;

pBasicHist.GetHistogram(out dataValues, out dataFrequency);

IClassifyGEN pClassifyGEN = new QuantileClass();

pClassifyGEN.Classify(dataValues, dataFrequency, ref numClass);

Classes = (double[])pClassifyGEN.ClassBreaks;

ClassesCount = long.Parse(Classes.GetUpperBound(0).ToString());

//Initialise a new class breaks renderer and supply the number of class breaks and the field to perform. the class breaks on.

IClassBreaksRenderer pClassBreaksRenderer = new ClassBreaksRendererClass();

pClassBreaksRenderer.Field = "w1";

//pClassBreaksRenderer.BreakCount = ClassesCount;

pClassBreaksRenderer.MinimumBreak = Classes[0];

pClassBreaksRenderer.SortClassesAscending = true;

//设置着色对象的分级数目

pClassBreaksRenderer.BreakCount = int.Parse(ClassesCount.ToString());

//创建并设置随机色谱

IAlgorithmicColorRamp pColorRamp = new AlgorithmicColorRampClass();

pColorRamp.Algorithm = esriColorRampAlgorithm.esriCIELabAlgorithm;

IEnumColors pEnumColors;

IRgbColor pColor1 = new RgbColorClass();

IRgbColor pColor2 = new RgbColorClass();

pColor1.Red = 255;

pColor1.Green = 210;

pColor1.Blue = 210;

pColor2.Red = 190;

pColor2.Green = 0;

pColor2.Blue = 170;

pColorRamp.FromColor = pColor1;

pColorRamp.ToColor = pColor2;

pColorRamp.Size = numClass;

bool ok = true;

//pColorRamp.CreateRamp(out ok);

pColorRamp.CreateRamp(out ok);

pEnumColors = pColorRamp.Colors;

pEnumColors.Reset();// use this interface to set dialog properties

pUIProperties = pClassBreaksRenderer as IClassBreaksUIProperties;

pUIProperties.ColorRamp = "Custom";

ISimpleFillSymbol pSimpleMarkerSymbol = new SimpleFillSymbolClass();

IColor pColor;

int[] colors = new int[numClass];

// be careful, indices are different for the diff lists

for (breakIndex = 0; breakIndex < ClassesCount; breakIndex++)

{

pClassBreaksRenderer.set_Label(breakIndex, Classes[breakIndex] + " - " + Classes[breakIndex + 1]);

pUIProperties.set_LowBreak(breakIndex, Classes[breakIndex]);

pSimpleMarkerSymbol = new SimpleFillSymbolClass();

pColor = pEnumColors.Next();

pSimpleMarkerSymbol.Color = pColor;

colors[breakIndex] = pColor.RGB;

pClassBreaksRenderer.set_Symbol(breakIndex, (ISymbol)pSimpleMarkerSymbol);

pClassBreaksRenderer.set_Break(breakIndex, Classes[breakIndex + 1]);

}

//将等级图渲染对象与渲染图层挂钩

pGeoFeatureLayer.Renderer = (IFeatureRenderer)pClassBreaksRenderer;

//刷新地图和TOOCotrol

IActiveView pActiveView = axMapControl1.Map as IActiveView;

pActiveView.Refresh();

axTOCControl1.Update();

}

from:  http://blog.sina.com.cn/s/blog_90b91bf101015jkj.html

http://blog.sina.com.cn/s/blog_642c66ed0101cs5m.html