public static void CategorizeNumericPointLayer(Shapefile sf, int classificationField = 1,
tkClassificationType Method = tkClassificationType.ctNaturalBreaks)
{
float ptSize = 0;
if (sf.Categories.Generate(classificationField, Method, NumberOfCategories))
{
for (int n = 0; n < sf.Categories.Count; n++)
{
var category = sf.Categories.Item[n];
ptSize = PointSizeOfMaxCategory * ((float)(n + 1) / sf.Categories.Count);
category.DrawingOptions.PointSize = ptSize;
category.DrawingOptions.LineColor = new Utils().ColorByName(tkMapColor.White);
}
}
var cat0 = sf.Categories.Add("zero");
Field f = sf.Field[classificationField];
cat0.Expression = $"[{f.Name}]=0";
cat0.DrawingOptions.PointSize = 0;
cat0.DrawingOptions.FillVisible = false;
cat0.DrawingOptions.LineVisible = false;
sf.Categories.ApplyExpression(sf.Categories.CategoryIndex[cat0]);
}
/// <summary>
/// Creates the specified number of visualization categories and expressions for them.
/// </summary>
/// <remarks>The method can be useful to override generation routine provided in ShapefileCategories.GenerateCategories()
/// which always generate categories covering the full range of values of the specified field. This method can
/// define the range of values explicitly, therefore certain values can be excluded from classification or on contrary
/// categories can be added for the values which aren't yet present in the table.</remarks>
/// <param name="FieldIndex">The index of the field to build classification by.</param>
/// <param name="ClassificationType">The type of the classification.</param>
/// <param name="numClasses">The number of categories to add. If ClassificationType equals ctUniqueValues this value will be skipped.</param>
/// <param name="MinValue">The minimal value of the field to include in the classification.</param>
/// <param name="MaxValue">Th maximum value of the field to include in the classification.</param>
/// <returns>True on successful adding and false otherwise.</returns>
public bool AddRange(int FieldIndex, tkClassificationType ClassificationType, int numClasses, object MinValue, object MaxValue)
{
throw new NotImplementedException();
}
/// <summary>
/// Generates categories based on specified field.
/// </summary>
/// <param name="FieldName">Name of the field.</param>
/// <param name="ClassificationType">Type of the classification.</param>
/// <param name="numClasses">The number classes.</param>
/// <returns>True on success.</returns>
/// \new494 Added in version 4.9.4
public bool Generate2(string FieldName, tkClassificationType ClassificationType, int numClasses)
{
throw new NotImplementedException();
}
/// <summary>
/// Generates visualization categories by certain attribute
/// </summary>
/// <param name="FieldIndex">The index of the field to generate categories by.</param>
/// <param name="ClassificationType">The type of classification.</param>
/// <param name="numClasses">Number of classes to generate. The parameter is omitted
/// in case unique values classification is used.</param>
/// <returns>True on successful generation and false otherwise.</returns>
public bool Generate(int FieldIndex, tkClassificationType ClassificationType, int numClasses)
{
throw new NotImplementedException();
}
/// <summary>
/// Builds classification for the raster band.
/// </summary>
/// <param name="MinValue">The minimum value.</param>
/// <param name="MaxValue">The maximum value.</param>
/// <param name="classification">The classification type.</param>
/// <param name="NumCategories">The number of categories.</param>
/// <returns>Resulting classification.</returns>
public GridColorScheme Classify(double MinValue, double MaxValue, tkClassificationType classification, int NumCategories)
{
throw new NotImplementedException();
}
/// <summary>
/// Generates visualization categories for OGR layer.
/// </summary>
/// <param name="Fieldname">%Field name to use as a base for classification.</param>
/// <param name="ClassificationType">Type of classification.</param>
/// <param name="numClasses">Number of classes (is not used with unique values classification type).</param>
/// <param name="colorStart">Starting color for the color scheme.</param>
/// <param name="colorEnd">End color for the color scheme.</param>
/// <param name="schemeType">Type of color scheme.</param>
/// <returns>True on success.</returns>
/// <remarks> The whole set of features will be used during classification, not only those currently loaded into memory.
/// Therefore the method has definite advantage over calling OgrLayer.GetBuffer.Categories.Generate
/// directly for large layers.\n\n
///
/// Categories will be added to underlying shapefile (OgrLayer.GetBuffer). This method
/// will trigger the population of this shapefile if it's not yet in memory. \n
///
/// The following code opens "buildings" layer, generates categories based on "population"
/// field and then saves them as a "new_style" to the datasource.\n
///
/// \code
/// var layer = new OgrLayer();
/// if (!layer.OpenFromDatabase(CONNECTION_STRING, "buildings"))
/// {
/// Debug.WriteLine("Failed to open the layer: " + layer.GdalLastErrorMsg);
/// }
/// else
/// {
/// layer.LabelExpression = "[Name]";
/// layer.LabelPosition = tkLabelPositioning.lpCenter;
/// layer.GlobalCallback = this;
///
/// if (!layer.GenerateCategories("population", tkClassificationType.ctEqualIntervals,
/// 10, tkMapColor.Blue, tkMapColor.Yellow, tkColorSchemeType.ctSchemeGraduated))
/// {
/// Debug.WriteLine("Failed to generated categories: " + layer.get_ErrorMsg(layer.LastErrorCode));
/// }
/// else
/// {
/// var sf = layer.GetBuffer();
/// Debug.WriteLine("Number of generated categories: " + sf.Categories.Count);
///
/// // save it as a new style
/// if (!layer.SaveStyle("new_style"))
/// {
/// Debug.WriteLine("Failed to save style: " + layer.GdalLastErrorMsg);
/// }
/// else
/// {
/// Debug.WriteLine("The new style has been saved.");
/// }
/// }
/// layer.Close();
/// }
/// \endcode
/// </remarks>
public bool GenerateCategories(string Fieldname, tkClassificationType ClassificationType, int numClasses,
tkMapColor colorStart, tkMapColor colorEnd, tkColorSchemeType schemeType)
{
throw new NotImplementedException();
}