/// <summary>
/// 获取绘图工具（绘制非持久图形）
/// </summary>
/// <returns></returns>
public moUserDrawingTool GetDrawingTool()
{
Graphics g = Graphics.FromHwnd(this.Handle);
moUserDrawingTool sDrawingTool = CreateDrawingTool(g);
return(sDrawingTool);
}
/// <summary>
/// 新建一个绘图工具
/// </summary>
/// <returns></returns>
private moUserDrawingTool CreateDrawingTool(Graphics graphics)
{
moRectangle sExtent = GetExtent();
double sMapScale = mMapDrawingReference.MapScale;
double dpm = mMapDrawingReference.dpm;
double mpu = mMapDrawingReference.mpu;
moUserDrawingTool sDrawingTool = new moUserDrawingTool(graphics, sExtent, sMapScale, dpm, mpu);
return(sDrawingTool);
}
private void DrawBufferMap2()
{
//（1）获取地图窗口的范围
moRectangle sExtent = GetExtent();
if (sExtent.IsEmpty == true)
{
return;
}
//（2）绘制缓冲位图1
Graphics g = Graphics.FromImage(mBufferMap2);
g.Clear(Color.White);
Rectangle sRect = new Rectangle(0, 0, mBufferMap1.Width, mBufferMap1.Height);
g.DrawImage(mBufferMap1, sRect, sRect, GraphicsUnit.Pixel);
//（3）绘制所有图层的选择要素，采用倒序
double sMapScale = mMapDrawingReference.MapScale;
double dpm = mMapDrawingReference.dpm;
double mpu = mMapDrawingReference.mpu;
Int32 sLayerCount = _Layers.Count;
for (Int32 i = sLayerCount - 1; i >= 0; i--)
{
moMapLayer sLayer = _Layers.GetItem(i);
if (sLayer.ShapeType == moGeometryTypeConstant.Point)
{
sLayer.DrawSelectedFeatures(g, sExtent, sMapScale, dpm, mpu, mSelectedPointSymbol);
}
else if (sLayer.ShapeType == moGeometryTypeConstant.MultiPolyline)
{
sLayer.DrawSelectedFeatures(g, sExtent, sMapScale, dpm, mpu, mSelectedLineSymbol);
}
else if (sLayer.ShapeType == moGeometryTypeConstant.MultiPolygon)
{
sLayer.DrawSelectedFeatures(g, sExtent, sMapScale, dpm, mpu, mSelectedFillSymbol);
}
}
//（4）触发事件，以便用户程序继续绘图
if (AfterTrackingLayerDraw != null)
{
//新建绘图工具
moUserDrawingTool sDrawingTool = CreateDrawingTool(g);
AfterTrackingLayerDraw(this, sDrawingTool);
}
g.Dispose();
}