GRASS GIS 8 Programmer's Manual  8.2.2dev(2023)-3d2c704037
cnversions.c
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1 #include <math.h>
2 #include <grass/gis.h>
3 #include <grass/display.h>
4 
5 /****** OLD CODE
6 * #include "windround.h"
7 **********/
8 /* D_do_conversions(window, t, b, l, r)
9  * struct Cell_head *window ;
10  * int t, b, l, r ;
11  *
12  * Sets up conversion coefficients to translate between three
13  * coordinate systems:
14  *
15  * 1. Screen coordinates (given by t, b, l, r values)
16  * 2. UTM coordinates (given by values in window structure)
17  * 3. Window array coors (given by values in window structure)
18  *
19  * Once D_do_conversions is called, lots of conversion coefficients
20  * and conversion routines are available.
21  *
22  * Calls to convert row and column (x and y) values in one system to
23  * another system are available. In addition calls which return the
24  * conversion coefficients are alos provided.
25  */
26 
27 struct vector
28 {
29  double x, y;
30 };
31 
32 struct rect
33 {
34  double west;
35  double east;
36  double south;
37  double north;
38  struct vector size;
39 };
40 
41 /* Bounding rectangles */
42 static struct rect D; /* Display coordinates, pixels, (0,0) towards NW */
43 static struct rect A; /* Map array coordinates, integers, (0,0) towards NW */
44 static struct rect U; /* UTM coordinates, meters, (0,0) towards SW */
45 
46 /* Conversion factors */
47 static struct vector D_to_A_conv; /* Display to Array */
48 static struct vector A_to_U_conv; /* Array to UTM */
49 static struct vector U_to_D_conv; /* UTM to Display */
50 
51 /* others */
52 static int is_lat_lon;
53 
54 
55 static void calc_size(struct rect *rect)
56 {
57  rect->size.x = rect->east - rect->west;
58  rect->size.y = rect->south - rect->north;
59 }
60 
61 static void calc_conv(struct vector *conv,
62  const struct vector *src, const struct vector *dst)
63 {
64  conv->x = dst->x / src->x;
65  conv->y = dst->y / src->y;
66 }
67 
68 static void fit_aspect(struct rect *rect, const struct rect *ref)
69 {
70  struct vector conv;
71  double scale, size, delta;
72 
73  calc_conv(&conv, &rect->size, &ref->size);
74 
75  if (fabs(conv.y) > fabs(conv.x)) {
76  scale = fabs(conv.y) / fabs(conv.x);
77  size = rect->size.x / scale;
78  delta = rect->size.x - size;
79  rect->west += delta/2;
80  rect->east -= delta/2;
81  rect->size.x = size;
82  }
83  else {
84  scale = fabs(conv.x) / fabs(conv.y);
85  size = rect->size.y / scale;
86  delta = rect->size.y - size;
87  rect->north += delta/2;
88  rect->south -= delta/2;
89  rect->size.y = size;
90  }
91 }
92 
94 {
95  calc_conv(&D_to_A_conv, &D.size, &A.size);
96  calc_conv(&A_to_U_conv, &A.size, &U.size);
97  calc_conv(&U_to_D_conv, &U.size, &D.size);
98 }
99 
100 void D_fit_d_to_u(void)
101 {
102  fit_aspect(&D, &U);
103 }
104 
105 void D_fit_u_to_d(void)
106 {
107  fit_aspect(&U, &D);
108 }
109 
111 {
112  fprintf(stderr,
113  " D_w %10.1f D_e %10.1f D_s %10.1f D_n %10.1f\n",
114  D.west, D.east, D.south, D.north);
115  fprintf(stderr,
116  " A_w %10.1f A_e %10.1f A_s %10.1f A_n %10.1f\n",
117  A.west, A.east, A.south, A.north);
118  fprintf(stderr,
119  " U_w %10.1f U_e %10.1f U_s %10.1f U_n %10.1f\n",
120  U.west, U.east, U.south, U.north);
121 
122  fprintf(stderr,
123  " D_x %10.1f D_y %10.1f\n" "\n", D.size.x, D.size.y);
124  fprintf(stderr,
125  " A_x %10.1f A_y %10.1f\n" "\n", A.size.x, A.size.y);
126  fprintf(stderr,
127  " U_x %10.1f U_y %10.1f\n" "\n", U.size.x, U.size.y);
128 
129  fprintf(stderr, " D_to_A_conv.x %10.1f D_to_A_conv.y %10.1f \n",
130  D_to_A_conv.x, D_to_A_conv.y);
131  fprintf(stderr, " A_to_U_conv.x %10.1f A_to_U_conv.y %10.1f \n",
132  A_to_U_conv.x, A_to_U_conv.y);
133  fprintf(stderr, " U_to_D_conv.x %10.1f U_to_D_conv.y %10.1f \n",
134  U_to_D_conv.x, U_to_D_conv.y);
135 }
136 
137 /*!
138  * \brief initialize conversions
139  *
140  * The relationship between the earth <b>region</b> and the <b>top, bottom,
141  * left</b>, and <b>right</b> screen coordinates is established, which then
142  * allows conversions between all three coordinate systems to be performed.
143  * Note this routine is called by <i>D_setup</i>.
144  *
145  * \param window region
146  * \param t top
147  * \param b bottom
148  * \param l left
149  * \param r right
150  * \return none
151  */
152 void D_do_conversions(const struct Cell_head *window,
153  double t, double b, double l, double r)
154 {
155  D_set_region(window);
156  D_set_dst(t, b, l, r);
157  D_fit_d_to_u();
159 #ifdef DEBUG
161 #endif /* DEBUG */
162 }
163 
164 
165 int D_is_lat_lon(void) { return (is_lat_lon); }
166 
167 double D_get_d_to_a_xconv(void) { return (D_to_A_conv.x); }
168 double D_get_d_to_a_yconv(void) { return (D_to_A_conv.y); }
169 double D_get_d_to_u_xconv(void) { return (1/U_to_D_conv.x); }
170 double D_get_d_to_u_yconv(void) { return (1/U_to_D_conv.y); }
171 double D_get_a_to_u_xconv(void) { return (A_to_U_conv.x); }
172 double D_get_a_to_u_yconv(void) { return (A_to_U_conv.y); }
173 double D_get_a_to_d_xconv(void) { return (1/D_to_A_conv.x); }
174 double D_get_a_to_d_yconv(void) { return (1/D_to_A_conv.y); }
175 double D_get_u_to_d_xconv(void) { return (U_to_D_conv.x); }
176 double D_get_u_to_d_yconv(void) { return (U_to_D_conv.y); }
177 double D_get_u_to_a_xconv(void) { return (1/A_to_U_conv.x); }
178 double D_get_u_to_a_yconv(void) { return (1/A_to_U_conv.y); }
179 
180 double D_get_ns_resolution(void) { return D_get_a_to_u_yconv(); }
181 double D_get_ew_resolution(void) { return D_get_a_to_u_xconv(); }
182 
183 double D_get_u_west(void) { return (U.west); }
184 double D_get_u_east(void) { return (U.east); }
185 double D_get_u_north(void) { return (U.north); }
186 double D_get_u_south(void) { return (U.south); }
187 
188 double D_get_a_west(void) { return (A.west); }
189 double D_get_a_east(void) { return (A.east); }
190 double D_get_a_north(void) { return (A.north); }
191 double D_get_a_south(void) { return (A.south); }
192 
193 double D_get_d_west(void) { return (D.west); }
194 double D_get_d_east(void) { return (D.east); }
195 double D_get_d_north(void) { return (D.north); }
196 double D_get_d_south(void) { return (D.south); }
197 
198 void D_set_region(const struct Cell_head *window)
199 {
200  D_set_src(window->north, window->south, window->west, window->east);
201  D_set_grid(0, window->rows, 0, window->cols);
202  is_lat_lon = (window->proj == PROJECTION_LL);
203 }
204 
205 void D_set_src(double t, double b, double l, double r)
206 {
207  U.north = t;
208  U.south = b;
209  U.west = l;
210  U.east = r;
211  calc_size(&U);
212 }
213 
214 /*!
215  * \brief returns frame bounds in source coordinate system
216  *
217  * D_get_src() returns the frame bounds in the source coordinate system
218  * (used by D_* functions)
219  *
220  * \param t top
221  * \param b bottom
222  * \param l left
223  * \param r right
224  * \return void
225  */
226 void D_get_src(double *t, double *b, double *l, double *r)
227 {
228  *t = U.north;
229  *b = U.south;
230  *l = U.west;
231  *r = U.east;
232 }
233 
234 void D_set_grid(int t, int b, int l, int r)
235 {
236  A.north = t;
237  A.south = b;
238  A.west = l;
239  A.east = r;
240  calc_size(&A);
241 }
242 
243 void D_get_grid(int *t, int *b, int *l, int *r)
244 {
245  *t = A.north;
246  *b = A.south;
247  *l = A.west;
248  *r = A.east;
249 }
250 
251 void D_set_dst(double t, double b, double l, double r)
252 {
253  D.north = t;
254  D.south = b;
255  D.west = l;
256  D.east = r;
257  calc_size(&D);
258 }
259 
260 /*!
261  * \brief returns frame bounds in destination coordinate system
262  *
263  * D_get_dst() returns the frame bounds in the destination coordinate system
264  * (used by R_* commands).
265  * The various D_setup() commands all set the destination coordinate
266  * system to the current frame reported by R_get_window().
267  *
268  * \param t top
269  * \param b bottom
270  * \param l left
271  * \param r right
272  * \return none
273  */
274 void D_get_dst(double *t, double *b, double *l, double *r)
275 {
276  *t = D.north;
277  *b = D.south;
278  *l = D.west;
279  *r = D.east;
280 }
281 
282 void D_get_u(double x[2][2])
283 {
284  x[0][0] = U.west;
285  x[0][1] = U.east;
286  x[1][0] = U.north;
287  x[1][1] = U.south;
288 }
289 
290 void D_get_a(int x[2][2])
291 {
292  x[0][0] = (int)A.west;
293  x[0][1] = (int)A.east;
294  x[1][0] = (int)A.north;
295  x[1][1] = (int)A.south;
296 }
297 
298 void D_get_d(double x[2][2])
299 {
300  x[0][0] = D.west;
301  x[0][1] = D.east;
302  x[1][0] = D.north;
303  x[1][1] = D.south;
304 }
305 
306 /*!
307  * \brief screen to array (y)
308  *
309  * Returns a <i>row</i> value in the array coordinate system when provided the
310  * corresponding <b>y</b> value in the screen coordinate system.
311  *
312  * \param D_row y
313  * \return double
314  */
315 
316 double D_d_to_a_row(double D_row)
317 {
318  return A.north + (D_row - D.north) * D_to_A_conv.y;
319 }
320 
321 
322 /*!
323  * \brief screen to array (x)
324  *
325  * Returns a <i>column</i> value in the array coordinate system when provided the
326  * corresponding <b>x</b> value in the screen coordinate system.
327  *
328  * \param D_col x
329  * \return double
330  */
331 
332 double D_d_to_a_col(double D_col)
333 {
334  return A.west + (D_col - D.west) * D_to_A_conv.x;
335 }
336 
337 
338 /*!
339  * \brief screen to earth (y)
340  *
341  * Returns a <i>north</i> value in the earth coordinate system when provided the
342  * corresponding <b>y</b> value in the screen coordinate system.
343  *
344  * \param D_row y
345  * \return double
346  */
347 
348 double D_d_to_u_row(double D_row)
349 {
350  return U.north + (D_row - D.north) / U_to_D_conv.y;
351 }
352 
353 
354 /*!
355  * \brief screen to earth (x)
356  *
357  * Returns an <i>east</i> value in the earth coordinate system when provided the
358  * corresponding <b>x</b> value in the screen coordinate system.
359  *
360  * \param D_col x
361  * \return double
362  */
363 
364 double D_d_to_u_col(double D_col)
365 {
366  return U.west + (D_col - D.west) / U_to_D_conv.x;
367 }
368 
369 
370 /*!
371  * \brief array to earth (row)
372  *
373  * Returns a <i>y</i> value in the earth coordinate system when provided the
374  * corresponding <b>row</b> value in the array coordinate system.
375  *
376  * \param A_row row
377  * \return double
378  */
379 
380 double D_a_to_u_row(double A_row)
381 {
382  return U.north + (A_row - A.north) * A_to_U_conv.y;
383 }
384 
385 
386 /*!
387  * \brief array to earth (column)
388  *
389  * Returns an <i>x</i> value in the earth coordinate system when
390  * provided the corresponding <b>column</b> value in the array coordinate
391  * system.
392  *
393  * \param A_col column
394  * \return double
395  */
396 
397 double D_a_to_u_col(double A_col)
398 {
399  return U.west + (A_col - A.west) * A_to_U_conv.x;
400 }
401 
402 
403 /*!
404  * \brief array to screen (row)
405  *
406  * Returns a <i>y</i> value in the screen coordinate system when provided the
407  * corresponding <b>row</b> value in the array coordinate system.
408  *
409  * \param A_row row
410  * \return double
411  */
412 
413 double D_a_to_d_row(double A_row)
414 {
415  return D.north + (A_row - A.north) / D_to_A_conv.y;
416 }
417 
418 
419 /*!
420  * \brief array to screen (column)
421  *
422  * Returns an <i>x</i> value in the screen coordinate system when
423  * provided the corresponding <b>column</b> value in the array coordinate
424  * system.
425  *
426  * \param A_col column
427  * \return double
428  */
429 
430 double D_a_to_d_col(double A_col)
431 {
432  return D.west + (A_col - A.west) / D_to_A_conv.x;
433 }
434 
435 
436 /*!
437  * \brief earth to screen (north)
438  *
439  * Returns a <i>y</i> value in the screen coordinate system when provided the
440  * corresponding <b>north</b> value in the earth coordinate system.
441  *
442  * \param U_row north
443  * \return double
444  */
445 
446 double D_u_to_d_row(double U_row)
447 {
448  return D.north + (U_row - U.north) * U_to_D_conv.y;
449 }
450 
451 
452 /*!
453  * \brief earth to screen (east)
454  *
455  * Returns an <i>x</i> value in the screen coordinate system when provided the
456  * corresponding <b>east</b> value in the earth coordinate system.
457  *
458  * \param U_col east
459  * \return double
460  */
461 
462 double D_u_to_d_col(double U_col)
463 {
464  return D.west + (U_col - U.west) * U_to_D_conv.x;
465 }
466 
467 
468 /*!
469  * \brief earth to array (north)
470  *
471  * Returns a <i>row</i> value in the array coordinate system when provided the
472  * corresponding <b>north</b> value in the earth coordinate system.
473  *
474  * \param U_row north
475  * \return double
476  */
477 
478 double D_u_to_a_row(double U_row)
479 {
480  return A.north + (U_row - U.north) / A_to_U_conv.y;
481 }
482 
483 
484 /*!
485  * \brief earth to array (east
486  *
487  * Returns a <i>column</i> value in the array coordinate system when provided the
488  * corresponding <b>east</b> value in the earth coordinate system.
489  *
490  * \param U_col east
491  * \return double
492  */
493 
494 double D_u_to_a_col(double U_col)
495 {
496  return A.west + (U_col - U.west) / A_to_U_conv.x;
497 }
double D_d_to_a_col(double D_col)
screen to array (x)
Definition: cnversions.c:332
double D_u_to_a_row(double U_row)
earth to array (north)
Definition: cnversions.c:478
double D_get_a_east(void)
Definition: cnversions.c:189
double D_get_d_to_u_xconv(void)
Definition: cnversions.c:169
void D_set_src(double t, double b, double l, double r)
Definition: cnversions.c:205
void D_get_dst(double *t, double *b, double *l, double *r)
returns frame bounds in destination coordinate system
Definition: cnversions.c:274
double D_get_d_to_a_xconv(void)
Definition: cnversions.c:167
2D/3D raster map header (used also for region)
Definition: gis.h:423
double D_get_u_to_d_yconv(void)
Definition: cnversions.c:176
int D_is_lat_lon(void)
Definition: cnversions.c:165
double west
Extent coordinates (west)
Definition: gis.h:475
double D_a_to_u_row(double A_row)
array to earth (row)
Definition: cnversions.c:380
double D_d_to_a_row(double D_row)
screen to array (y)
Definition: cnversions.c:316
char * dst
Definition: lz4.h:599
void D_get_grid(int *t, int *b, int *l, int *r)
Definition: cnversions.c:243
void D_fit_u_to_d(void)
Definition: cnversions.c:105
double D_d_to_u_col(double D_col)
screen to earth (x)
Definition: cnversions.c:364
#define x
double D_get_d_west(void)
Definition: cnversions.c:193
double D_get_u_north(void)
Definition: cnversions.c:185
double D_get_a_to_d_xconv(void)
Definition: cnversions.c:173
double D_get_a_south(void)
Definition: cnversions.c:191
double D_get_ew_resolution(void)
Definition: cnversions.c:181
#define D
Definition: gis/intersect.c:74
double D_get_a_west(void)
Definition: cnversions.c:188
double l
Definition: r_raster.c:39
double t
Definition: r_raster.c:39
double D_get_u_east(void)
Definition: cnversions.c:184
double north
Extent coordinates (north)
Definition: gis.h:469
double D_get_d_east(void)
Definition: cnversions.c:194
double D_get_d_north(void)
Definition: cnversions.c:195
double b
Definition: r_raster.c:39
void D_fit_d_to_u(void)
Definition: cnversions.c:100
void D_set_grid(int t, int b, int l, int r)
Definition: cnversions.c:234
double D_u_to_d_col(double U_col)
earth to screen (east)
Definition: cnversions.c:462
void D_get_u(double x[2][2])
Definition: cnversions.c:282
double south
Extent coordinates (south)
Definition: gis.h:471
double D_get_a_north(void)
Definition: cnversions.c:190
double D_get_ns_resolution(void)
Definition: cnversions.c:180
#define PROJECTION_LL
Projection code - Latitude-Longitude.
Definition: gis.h:116
void D_do_conversions(const struct Cell_head *window, double t, double b, double l, double r)
initialize conversions
Definition: cnversions.c:152
double D_get_d_to_u_yconv(void)
Definition: cnversions.c:170
double D_get_a_to_d_yconv(void)
Definition: cnversions.c:174
double D_get_u_south(void)
Definition: cnversions.c:186
int proj
Projection code.
Definition: gis.h:455
double D_u_to_a_col(double U_col)
earth to array (east
Definition: cnversions.c:494
double D_a_to_d_row(double A_row)
array to screen (row)
Definition: cnversions.c:413
double D_get_u_to_a_xconv(void)
Definition: cnversions.c:177
void D_show_conversions(void)
Definition: cnversions.c:110
void D_update_conversions(void)
Definition: cnversions.c:93
double D_get_a_to_u_yconv(void)
Definition: cnversions.c:172
void D_set_dst(double t, double b, double l, double r)
Definition: cnversions.c:251
double D_get_d_south(void)
Definition: cnversions.c:196
double D_get_u_to_d_xconv(void)
Definition: cnversions.c:175
int cols
Number of columns for 2D data.
Definition: gis.h:442
double D_a_to_u_col(double A_col)
array to earth (column)
Definition: cnversions.c:397
double D_get_d_to_a_yconv(void)
Definition: cnversions.c:168
double east
Extent coordinates (east)
Definition: gis.h:473
double D_get_a_to_u_xconv(void)
Definition: cnversions.c:171
double D_d_to_u_row(double D_row)
screen to earth (y)
Definition: cnversions.c:348
void D_get_d(double x[2][2])
Definition: cnversions.c:298
void D_get_a(int x[2][2])
Definition: cnversions.c:290
int rows
Number of rows for 2D data.
Definition: gis.h:438
double D_u_to_d_row(double U_row)
earth to screen (north)
Definition: cnversions.c:446
void D_set_region(const struct Cell_head *window)
Definition: cnversions.c:198
double D_get_u_west(void)
Definition: cnversions.c:183
double r
Definition: r_raster.c:39
double D_a_to_d_col(double A_col)
array to screen (column)
Definition: cnversions.c:430
void D_get_src(double *t, double *b, double *l, double *r)
returns frame bounds in source coordinate system
Definition: cnversions.c:226
double D_get_u_to_a_yconv(void)
Definition: cnversions.c:178