NAME
RcomputeExtend - compute (xUL,yUL) and nrRows, nrCols from some coordinates
SYNOPSIS
#include "csf.h"
void RcomputeExtend
(
REAL8 *xUL,
REAL8 *yUL,
size_t *nrRows,
size_t *nrCols,
double x_1,
double y_1,
double x_2,
double y_2,
CSF_PT projection,
REAL8 cellSize,
double rounding
);
PARAMETERS
-
REAL8 *xUL
-
write-only, resulting xUL
-
REAL8 *yUL
-
write-only, resulting yUL
-
size_t *nrRows
-
write-only, resulting nrRows
-
size_t *nrCols
-
write-only, resulting nrCols
-
double x_1
-
first x-coordinate
-
double y_1
-
first y-coordinate
-
double x_2
-
second x-coordinate
-
double y_2
-
second y-coordinate
-
CSF_PT projection
-
required projection
Possible values for a
CSF_PT
are as follows:
* these two can be returned by or passed to a csf2 function
- PT_YINCT2B - Y increase from top to bottom.
- PT_YDECT2B - Y decrease from top to bottom.
* this one CANNOT be returned by NOR passed to a csf2 function
- PT_UNDEFINED - Just some value different from the rest.
-
REAL8 cellSize
-
required cellsize, > 0
-
double rounding
-
assure that (xUL/rounding), (yUL/rouding)
(xLL/rounding) and (yLL/rounding) will
will all be an integers values > 0
DESCRIPTION
RcomputeExtend computes parameters to create a raster maps
from minimum and maximum x and y coordinates, projection information,
cellsize and units. The resulting parameters are computed that the
smallest raster map can be created that will include the two
coordinates given, assuming a default angle of 0.
Which coordinates are the maximum or minimum are
determined by the function itself.