IRasterGeometryProc::ProjectFast does not generate square size raster

Description

When projecting a raster using IRasterGeometryProc::ProjectFast, the cell size of the output raster is not square even though the signature allows a square cell size to be specified.

Cause

This is a known problem with ArcGIS 8.1.

Solution or Workaround

1. Use IRasterProperty::SpatialReference to set the Spatial Reference to a Raster.
2. Calculate the current raster's height and width, based on the current raster's extent and the cell size.
3. Update the current raster's extent accordingly so that:
   
   

   n*Cell size = Extent in X dimension and
   m*Cell size = Extent in Y dimension. 

   
   
4. Set the current raster's extent and then set the raster's column and row.
   
   

   Note:
   The sequence you follow does matter.