Pitney Bowes MapXtreme - Manual (Page 323)

Chapter 17: Working with Rasters and Grids
Grid Style
MapXtreme v7.1 330 Developer Guide
Grid Images and Inflections
A continuous grid image shows an interpolation of data values across an area. A grid is made up of
grid cells where each cell represents a value. These values are represented on the map as a
continuous color gradation that is bounded by the range of data values.
The point at which the color changes due to a change in the grid value or percentage is known as an
inflection. MapXtreme creates a GridInflectionCalculator object that calculates inflection values
based on one of several supported methods. The number of inflection points for a grid coupled with
the minimum and maximum range of data values is used to determine the color gradation across the
map. The color that represents the inflection is applied to the grid as a FeatureStyleOverrideModifier.
Inflection Methods
MapXtreme supports the following calculation methods:
• Equal Cell Count–Calculates inflection values so that an equal number of cell values are within
the calculated percentage ranges.
• Equal Value Ranges–Calculates inflection values in a manner where each inflection value range
is the same size.
• Custom Cell Count–Same as Equal Cell Count, except uses custom percentage ranges.
• Custom Value Ranges–Same as Equal Value Ranges, except uses custom inflection values.
Inflection values and colors can be modified programmatically through the
MapInfo.Raster.GridInflectionCalculator class. A GridStyleControl is available from the MapXtreme
toolbox in Visual Studio.