smlgeo.sml

# smlgeo.sml
#
# SML script to demonstrate creation of georef object in SML
#
# 1. opens a Raster - cb_tm/blue
# 2. creates a new Vector object and draws a box
# 3. georeferences the Vector so that it bounds the raster
#
# NOTES:
# 1. you must use a minimum of three control points 
# 2. they must not be all on the same line!
#
#
# AUTHOR: 			David Wilson
# 						MicroImages, Inc.
# REQUESTED BY:
# CREATION DATE: 	Nov. 4, 1997
# REVISION LIST: 
#

#########################################################################################
#
# alternate method to get extents of object
#
# can use this in general - if last parm is omitted then returns object coordinates
#
# rgeoref = GetLastUsedGeorefObject(Rin)
# GetObjectExtents(Rin, rxmin, rymin, rxmax, rymax, rgeoref)
#
# now do same for Vector except do not use georef parm
# this will give us object coordinates
# GetObjectExtents(Vout, vxmin, vymin, vxmax, vymax)
#
#########################################################################################


# the source arrays will hold the object coordinates
# for a raster this would be cell values
# for Vector, CAD, TIN it would be object, (non-georefenced), coordinates
array numeric xsrc[5], ysrc[5], zsrc[5];

# the destination arrays will hold the appropriate, (georeferenced), values
array numeric xdest[5], ydest[5], zdest[5];

# arrays to hold Vector points to draw box
array numeric xpoints[10];
array numeric ypoints[10];

# fill in the control points (source and destination) - need 3 minimum

# we will assume a georeferenced raster and a non-georeferenced vector 
# that we wish to georeference to the raster

clear();

raster Rin;
vector Vout;
class Georef rgeoref;
numeric numlines, numcols;
numeric xUL, yUL, xLR, yLR, xUR, yUR, xLL, yLL;

# get the raster
GetInputRaster(Rin);

# get number of lines and columns
numlines = NumLins(Rin);
numcols = NumCols(Rin);

# get the upper left (UL), lower right (LR) 
# upper right (UR), and lower left (LL) coordinates
rgeoref = GetLastUsedGeorefObject(Rin);
ObjectToMap(Rin, 0, 0, rgeoref, xUL, yUL);
ObjectToMap(Rin, numcols, numlines, rgeoref, xLR, yLR);
ObjectToMap(Rin, numcols, 0, rgeoref, xUR, yUR);
ObjectToMap(Rin, 0, numlines, rgeoref, xLL, yLL);

printf("UL: %7.2f %7.2f\n", xUL, yUL);
printf("UR: %7.2f %7.2f\n", xUR, yUR);
printf("LL: %7.2f %7.2f\n", xLL, yLL);
printf("LR: %7.2f %7.2f\n", xLR, yLR);

# create a new Vector here !!!!
# we will draw a box to and match it to the raster
GetOutputVector(Vout, "VectorToolkit");

# draw the box - this will create a polygon
# fill in the points
xpoints[1] = 0;
ypoints[1] = 0;
xpoints[2] = 100;
ypoints[2] = 0;
xpoints[3] = 100;
ypoints[3] = 100;
xpoints[4] = 0;
ypoints[4] = 100;
xpoints[5] = 0;
ypoints[5] = 0;

VectorAddLine(Vout, 5, xpoints, ypoints);


# fill in four control points - one for each corner
# the source values are for the Vector
 
# control point 1 - upper left corner
xsrc[1] = 0;
ysrc[1] = 100;
zsrc[1] = 0;

xdest[1] = xUL;
ydest[1] = yUL;
zdest[1] = 0;

# control point 2 - lower right corner
xsrc[2] = 100;
ysrc[2] = 0;
zsrc[2] = 0;

xdest[2] = xLR;
ydest[2] = yLR;
zdest[2] = 0;

# control point 3 - upper right corner
xsrc[3] = 100;
ysrc[3] = 100;
zsrc[3] = 0;

xdest[3] = xUR;
ydest[3] = yUR;
zdest[3] = 0;

# control point 3 - lower left corner
xsrc[4] = 0;
ysrc[4] = 0;
zsrc[4] = 0;

xdest[4] = xLL;
ydest[4] = yLL;
zdest[4] = 0;

# print out the control points
numeric i;
for i = 1 to 4 {
	printf("%s %2d %7.2f %7.2f %7.2f  ", "i: xsrc, ysrc, zsrc, xdest, ydest, zdest ", i, xsrc[i], ysrc[i], zsrc[i]);
	printf("%7.2f %7.2f %7.2f\n", xdest[i], ydest[i], zdest[i]);
	}

# set number of control points
numeric numpoints = 4;

# now create the georef via dialog
CreateControlPointGeoref(Vout, numpoints, xsrc, ysrc, zsrc, xdest, ydest, zdest);

GeorefFree(rgeoref);
CloseRaster(Rin);