Hi,
I have posted some minor cosmetic / printing patches in the past to the Gforge
site, however it looks like they were either overlooked- or not deemed worth
implementing.
The patch in mind enabled printing of the transformation matrix, as computed
by v.transform, when prompted by the user. I have tried to add this
functionality with a minimal impact on module design- and followed several of
Glynn's suggested coding practices. The patches are attached to this message.
If this is too specialized for v.transform I will continue to maintain my
local copies. What do people think?
Cheers,
Dylan
--
Dylan Beaudette
Soils and Biogeochemistry Graduate Group
University of California at Davis
530.754.7341
? lib/vector/transform/OBJ.i686-pc-linux-gnu
Index: lib/vector/transform/transform.c
===================================================================
RCS file: /home/grass/grassrepository/grass6/lib/vector/transform/transform.c,v
retrieving revision 1.2
diff -u -r1.2 transform.c
--- lib/vector/transform/transform.c 9 Feb 2006 03:08:58 -0000 1.2
+++ lib/vector/transform/transform.c 19 Sep 2007 19:04:54 -0000
@@ -60,7 +60,7 @@
double residual[] residual error for each point
double *rms; overall root mean square error
****************************************************************/
-
+#include <stdio.h>
#include <math.h>
#include <grass/libtrans.h>
@@ -68,6 +68,8 @@
static double A0,A1,A2,A3,A4,A5;
static double B0,B1,B2,B3,B4,B5;
+
+
static int resid(
double *,double *,double *,double *,int *,int,double *,double *,int);
@@ -144,6 +146,7 @@
B4 = bbr[1];
B5 = bbr[2];
+
/* the inverse equation */
x = B2 * B4 - B1 * B5 ;
@@ -180,6 +183,23 @@
return 0;
}
+
+
+/*
+return the transformation matrix in a convinient format
+*/
+int print_transform_matrix()
+ {
+ fprintf(stdout, "\nTransformation Matrix\n");
+ fprintf(stdout, "| xoff a b |\n");
+ fprintf(stdout, "| yoff d e |\n");
+ fprintf(stdout, "-------------------------------------\n");
+ fprintf(stdout, "%f %f %f \n", -B3, B2, -B5);
+ fprintf(stdout, "%f %f %f \n", -B0, -B1, B4);
+ fprintf(stdout, "-------------------------------------\n");
+ return 1 ;
+ }
+
/**************************************************************
These routines are internal to this source code
? vector/v.transform/OBJ.i686-pc-linux-gnu
Index: vector/v.transform/description.html
===================================================================
RCS file: /home/grass/grassrepository/grass6/vector/v.transform/description.html,v
retrieving revision 1.13
diff -u -r1.13 description.html
--- vector/v.transform/description.html 7 Sep 2007 14:10:36 -0000 1.13
+++ vector/v.transform/description.html 19 Sep 2007 19:07:48 -0000
@@ -37,6 +37,15 @@
parameters based on their category number. If the parameter cannot be
fetched from the table, default value is used instead.<p>
+<h3>Affine Transformation Matrix</h3>
+The affine transformation matrix can optionally be printed with the '-m' flag. The format of the matrix is:
+<div class="code" style="width:30%;"><pre>
+| x_offset a b |
+| y_offset d e |
+</pre></div>
+
+This format can be used in the <a href="http://postgis.refractions.net/docs/ch06.html#id2904406";>Affine() function of PostGIS</a> [Affine(geom, a, b, d, e, xoff, yoff)], or directly compared to the output of a similar operation performed in R.
+
<h2>EXAMPLE</h2>
<h3>DXF/DWG drawings</h3>
Index: vector/v.transform/main.c
===================================================================
RCS file: /home/grass/grassrepository/grass6/vector/v.transform/main.c,v
retrieving revision 1.34
diff -u -r1.34 main.c
--- vector/v.transform/main.c 7 Sep 2007 14:10:36 -0000 1.34
+++ vector/v.transform/main.c 19 Sep 2007 19:07:49 -0000
@@ -44,9 +44,10 @@
struct file_info Current, Trans, Coord;
struct GModule *module;
+
struct Option *old, *new, *pointsfile, *xshift, *yshift, *zshift,
*xscale, *yscale, *zscale, *zrot, *columns, *table, *field;
- struct Flag *quiet_flag, *tozero_flag, *shift_flag;
+ struct Flag *quiet_flag, *tozero_flag, *shift_flag, *print_mat_flag;;
char *mapset, mon[4], date[40], buf[1000];
struct Map_info Old, New;
@@ -77,7 +78,12 @@
tozero_flag = G_define_flag();
tozero_flag->key = 't';
tozero_flag->description = _("Shift all z values to bottom=0");
-
+
+
+ print_mat_flag = G_define_flag();
+ print_mat_flag->key = 'm';
+ print_mat_flag->description = _("Print the transformation matrix to stdout");
+
/* remove in GRASS7 */
shift_flag = G_define_flag();
shift_flag->key = 's';
@@ -321,15 +327,23 @@
if (!quiet_flag->answer) {
Vect_get_map_box (&New, &box );
- G_message ( _("New vector map <%s> boundary coordinates:"), new->answer);
+ G_message ( _("\nNew vector map <%s> boundary coordinates:"), new->answer);
G_message ( _(" N: %-10.3f S: %-10.3f"), box.N, box.S);
G_message ( _(" E: %-10.3f W: %-10.3f"), box.E, box.W);
G_message ( _(" B: %6.3f T: %6.3f"), box.B, box.T);
+
+ /*
+ print the transformation matrix if requested
+ */
+ if (print_mat_flag->answer)
+ print_transform_matrix();
+
}
Vect_close (&New);
G_done_msg (" ");
+
exit(EXIT_SUCCESS) ;
}
_______________________________________________
grass-dev mailing list
[email protected]
http://grass.itc.it/mailman/listinfo/grass-dev
