/// <summary>
/// Returns the style based on a numeric DataColumn, where style
/// properties are linearly interpolated between max and min values.
/// </summary>
/// <param name="row">Feature</param>
/// <returns><see cref="Mapsui.Styles.IStyle">Style</see> calculated by a linear interpolation between the min/max styles</returns>
public IStyle?GetStyle(IFeature row)
{
double attr;
try { attr = Convert.ToDouble(row[ColumnName.ToUpper()]); }
catch { throw new Exception("Invalid Attribute type in Gradient Theme - Couldn't parse attribute (must be numerical)"); }
if (MinStyle.GetType() != MaxStyle.GetType())
{
throw new ArgumentException("MinStyle and MaxStyle must be of the same type");
}
var style = (IStyle)Activator.CreateInstance(MinStyle.GetType()) !;
if (MinStyle is LabelStyle && MaxStyle is LabelStyle)
{
CalculateLabelStyle(style as LabelStyle, MinStyle as LabelStyle, MaxStyle as LabelStyle, attr);
}
if (MinStyle is VectorStyle && MaxStyle is VectorStyle)
{
CalculateVectorStyle(style as VectorStyle, MinStyle as VectorStyle, MaxStyle as VectorStyle, attr);
}
if (MinStyle is SymbolStyle && MaxStyle is SymbolStyle)
{
CalculateSymbolStyle(style as SymbolStyle, MinStyle as SymbolStyle, MaxStyle as SymbolStyle, attr);
}
return(style);
}
/// <summary>
/// Returns the style based on a numeric DataColumn, where style
/// properties are linearly interpolated between max and min values.
/// </summary>
/// <param name="feature">Feature</param>
/// <returns><see cref="SharpMap.Styles.IStyle">Style</see> calculated by a linear interpolation between the min/max styles</returns>
public override IStyle GetStyle(IFeature feature)
{
double attr;
try
{
attr = FeatureAttributeAccessorHelper.GetAttributeValue <double>(feature, attributeName);
}
catch
{
throw new ApplicationException(
"Invalid Attribute type in Gradient Theme - Couldn't parse attribute (must be numerical)");
}
if (MinStyle.GetType() != MaxStyle.GetType())
{
throw new ArgumentException("MinStyle and MaxStyle must be of the same type");
}
switch (MinStyle.GetType().FullName)
{
case "SharpMap.Styles.VectorStyle":
return(CalculateVectorStyle(attr));
case "SharpMap.Styles.LabelStyle":
return(CalculateLabelStyle(MinStyle as LabelStyle, MaxStyle as LabelStyle, attr));
default:
throw new ArgumentException(
"Only SharpMap.Styles.VectorStyle and SharpMap.Styles.LabelStyle are supported for the gradient theme");
}
}
/// <summary>
/// Returns the style based on a numeric DataColumn, where style
/// properties are linearly interpolated between max and min values.
/// </summary>
/// <param name="row">Feature</param>
/// <returns><see cref="SharpMap.Styles.IStyle">Style</see> calculated by a linear interpolation between the min/max styles</returns>
public IStyle GetStyle(FeatureDataRow row)
{
Double weighting;
try
{
weighting = Convert.ToDouble(row[_columnName]);
}
catch
{
throw new InvalidOperationException(
"Invalid attribute type in gradient theme. " +
"Couldn't parse weighting attribute (must be numeric).");
}
if (MinStyle == null)
{
throw new InvalidOperationException("Cannot create a gradient style if the MinStyle is missing.");
}
if (MaxStyle == null)
{
throw new InvalidOperationException("Cannot create a gradient style if the MaxStyle is missing.");
}
Type minStyleType = MinStyle.GetType();
Type maxStyleType = MaxStyle.GetType();
if (minStyleType != maxStyleType)
{
throw new ArgumentException("MinStyle and MaxStyle must be of the same type");
}
CalculateStyleDelegate styleCalculator;
_styleTypeFunctionTable.TryGetValue(minStyleType.TypeHandle, out styleCalculator);
if (styleCalculator == null)
{
throw new ArgumentException(
"Only SharpMap.Styles.VectorStyle and SharpMap.Styles.LabelStyle " +
"are supported for the gradient theme");
}
return(styleCalculator(MinStyle, MaxStyle, weighting));
}