/// <summary>
/// 将像素转换成地图单元
/// </summary>
/// <param name="pActiveView">提供各种转换信息</param>
/// <param name="pixelUnits">像素单元</param>
/// <returns>像素单元大小</returns>
public static double ConvertPixelsToMapUnits(IActiveView pActiveView, double pixelUnits)
{
if (pActiveView == null)
{
return(-1);
}
//获取 the ScreenDisplay
IScreenDisplay screenDisplay = pActiveView.ScreenDisplay;
//获取 DisplayTransformation
IDisplayTransformation displayTransformation = screenDisplay.DisplayTransformation;
//获取一个设备帧并用它来获得x轴方向上的像素数
tagRECT deviceRECT = displayTransformation.get_DeviceFrame();
int pixelExtent = (deviceRECT.right - deviceRECT.left);
//获取当前可是区域的地图范围
IEnvelope envelope = displayTransformation.VisibleBounds;
double realWorldDisplayExtent = envelope.Width;
//计算一个像素大小
if (pixelExtent == 0)
{
return(-1);
}
double sizeOfOnePixel = (realWorldDisplayExtent / pixelExtent);
//得出像素单元大小
return(pixelUnits * sizeOfOnePixel);
}
private static double GetLengthInMapUnits(IActiveView activeView, double mm)
{
if (activeView == null)
{
return(-1);
}
IScreenDisplay screenDisplay = activeView.ScreenDisplay;
IDisplayTransformation displayTransformation = screenDisplay.DisplayTransformation;
var dpi = displayTransformation.Resolution;
var inches = mm / 25.4;
tagRECT deviceRect = displayTransformation.get_DeviceFrame();
int pixelExtent = (deviceRect.right - deviceRect.left);
var pixels = dpi * inches;
IDistanceConverter distanceConverter = new DistanceConverter();
IEnvelope envelope = displayTransformation.VisibleBounds;
double realWorldDisplayExtent = envelope.Width;
if (pixelExtent == 0)
{
return(-1);
}
var sizeOfOnePixel = (realWorldDisplayExtent / pixelExtent);
return(pixels * sizeOfOnePixel);
}
public static IEnvelope GetSearchEnvelope(IActiveView pActiveView, IPoint pPoint)
{
try
{
double num = 6.0;
IEnvelope visibleBounds = null;
if (pActiveView != null)
{
IDisplayTransformation displayTransformation = pActiveView.ScreenDisplay.DisplayTransformation;
visibleBounds = displayTransformation.VisibleBounds;
tagRECT deviceFrame = displayTransformation.get_DeviceFrame();
double height = 0.0;
long num3 = 0L;
height = visibleBounds.Height;
num3 = deviceFrame.bottom - deviceFrame.top;
double num4 = 0.0;
num4 = height / ((double)num3);
num *= num4;
}
if (pPoint == null)
{
return(null);
}
visibleBounds = pPoint.Envelope;
visibleBounds.Width = num;
visibleBounds.Height = num;
visibleBounds.CenterAt(pPoint);
return(visibleBounds);
}
catch (Exception)
{
return(null);
}
}
/// <summary>
/// Converts the pixels to map units.
/// </summary>
/// <param name="activeView">The active view.</param>
/// <param name="targetSpatialRef">The target spatial reference.</param>
/// <param name="pixelValue">The pixel value.</param>
/// <param name="useWidth">if set to <c>true</c> [use width].</param>
/// <returns>System.Double.</returns>
public static double ConvertPixelsToMapUnits(IActiveView activeView, ISpatialReference targetSpatialRef, double pixelValue, bool useWidth = true)
{
double result;
if (activeView == null)
{
result = 0.0;
}
else if (pixelValue == 0.0)
{
result = 0.0;
}
else if (targetSpatialRef is IUnknownCoordinateSystem)
{
result = 0.0;
}
else
{
IDisplayTransformation displayTransformation = activeView.ScreenDisplay.DisplayTransformation;
IEnvelope visibleBounds = displayTransformation.VisibleBounds;
visibleBounds.Project(targetSpatialRef);
tagRECT deviceFrame = displayTransformation.get_DeviceFrame();
double num;
long num2;
if (useWidth)
{
num = visibleBounds.Width;
num2 = (long)(deviceFrame.right - deviceFrame.left);
}
else
{
num = visibleBounds.Height;
num2 = (long)(deviceFrame.bottom - deviceFrame.top);
}
if (num == 0.0)
{
result = 0.0;
}
else if (num2 == 0L)
{
result = 0.0;
}
else
{
double num3 = num / (double)num2;
result = pixelValue * num3;
}
}
return(result);
}
/// <summary>
/// 如果地图的参考比例尺被设定,该函数起作用,将指定的像素转换为地图的范围
/// </summary>
/// <param name="pMap">地图接口</param>
/// <param name="pixels">像素</param>
/// <returns>地图对应的范围</returns>
public static double ConvertPixels2ReferenceScaleMapUnits(IMap pMap, int pixels)
{
IActiveView pView = (IActiveView)pMap;
if (pMap.ReferenceScale > 0)
{
IDisplayTransformation pDT = pView.ScreenDisplay.DisplayTransformation;
tagRECT deviceRECT = pDT.get_DeviceFrame();
int pixelExtent = deviceRECT.right - deviceRECT.left;
IEnvelope pEnv = pDT.VisibleBounds;
double realWorldDisplayExtent = pEnv.Width;
double sizeOfOnePixel = realWorldDisplayExtent / pixelExtent;
return(pixels * sizeOfOnePixel);
}
return(pixels);
}
/// <summary>
/// Converts a screen pixel distance to the real distance.
/// </summary>
/// <param name="pixels">Number of pixels on the screen.</param>
/// <param name="display">Esri display.</param>
/// <returns>Real world distance.</returns>
public static double PixelsToDistance(int pixels, IScreenDisplay display)
{
IDisplayTransformation transformation = display.DisplayTransformation;
// get number of pixels in x axis
tagRECT deviceRect = transformation.get_DeviceFrame();
int pixelsOfMapWidth = deviceRect.right - deviceRect.left;
// get extent of visible area in map
IEnvelope mapExtent = transformation.VisibleBounds;
double distOfMapWidth = mapExtent.Width;
// calculate size of one pixel
double sizeOfPixel = distOfMapWidth / pixelsOfMapWidth;
return(sizeOfPixel * pixels);
}
/// <summary>
/// 屏幕距离转换为地图距离,用地图可视范围的宽度/设备宽，得到每个像素代表的地图长度
/// </summary>
/// <param name="pScreenDisplay"></param>
/// <param name="pixel"></param>
/// <returns></returns>
public static double ConvertPixelToMapUnit(IScreenDisplay pScreenDisplay, int pixel)
{
if (pScreenDisplay == null)
{
return(0);
}
IDisplayTransformation pDisplayTransformation = pScreenDisplay.DisplayTransformation;
tagRECT rectDevice = pDisplayTransformation.get_DeviceFrame();
IEnvelope pMapBoundary = pDisplayTransformation.VisibleBounds;
int nDeviceWidth = rectDevice.right - rectDevice.left;
double dMapWidth = pMapBoundary.Width;
return(pixel * (dMapWidth / nDeviceWidth));
}
public double ConvertPixelsToMapUnits(IActiveView pActiveView, double dPixelUnits, bool bWidthFlag)
{
try
{
if (pActiveView == null)
{
return(0.0);
}
if (dPixelUnits == 0.0)
{
return(0.0);
}
IDisplayTransformation displayTransformation = pActiveView.ScreenDisplay.DisplayTransformation;
IEnvelope visibleBounds = displayTransformation.VisibleBounds;
tagRECT deviceFrame = displayTransformation.get_DeviceFrame();
double width = 0.0;
long num2 = 0L;
if (bWidthFlag)
{
width = visibleBounds.Width;
num2 = deviceFrame.right - deviceFrame.left;
}
else
{
width = visibleBounds.Height;
num2 = deviceFrame.bottom - deviceFrame.top;
}
if (width == 0.0)
{
return(0.0);
}
if (num2 == 0L)
{
return(0.0);
}
double num3 = 0.0;
num3 = width / ((double)num2);
return(dPixelUnits * num3);
}
catch (Exception exception)
{
this.mErrOpt.ErrorOperate(this.mSubSysName, "FunFactory.UnitFun", "ConvertMapToPixelsUnits", exception.GetHashCode().ToString(), exception.Source, exception.Message, "", "", "");
return(-1.0);
}
}
public static double ConvertScreenPixelsToMapUnits(IScreenDisplay scrnDsp, double pixels)
{
IDisplayTransformation dspTransform = scrnDsp.DisplayTransformation;
double refScale = dspTransform.ReferenceScale;
if (refScale != 0)
{
double scaleRatio = dspTransform.ScaleRatio;
double pixelCount = dspTransform.ToPoints(scaleRatio);
double pixelSize = (double)scaleRatio / (double)pixelCount;
return(pixelSize * pixels);
}
else
{
tagRECT deviceFrame = dspTransform.get_DeviceFrame();
int pixelExtent = deviceFrame.right - deviceFrame.left;
IEnvelope visBounds = dspTransform.VisibleBounds;
double pixelSize = (double)visBounds.Width / (double)pixelExtent;
return(pixelSize * pixels);
}
}
/// <summary>
/// nDeviceFrameUpdated event handler
/// </summary>
/// <param name="sender"></param>
/// <param name="sizeChanged"></param>
private void OnDeviceFrameUpdated(IDisplayTransformation sender, bool sizeChanged)
{
//update the device frame rectangle
m_deviceFrame = sender.get_DeviceFrame();
}
/// <summary>
/// nDeviceFrameUpdated event handler
/// </summary>
/// <param name="sender"></param>
/// <param name="sizeChanged"></param>
private void OnDeviceFrameUpdated(IDisplayTransformation sender, bool sizeChanged)
{
//update the device frame rectangle
m_deviceFrame = sender.get_DeviceFrame();
}
