From 1e000e26e383837035b56e65219c7221ab3c29c9 Mon Sep 17 00:00:00 2001 From: Philip Schuchardt Date: Tue, 11 Aug 2026 19:55:12 -0500 Subject: [PATCH] cavern: Allow *cs custom to read the CRS from a file `*cs custom @FILENAME` reads the coordinate system description from a separate file. This makes it possible to specify a coordinate system as WKT or PROJJSON, which the .svx file itself can't carry because a quoted string has no way to represent the double quotes those formats are made of, and because they're usually written over several lines. --- doc/3dformat.htm | 9 +++- doc/datafile.rst | 35 +++++++++++++- src/commands.c | 115 ++++++++++++++++++++++++++++++++++++++++++++- src/filelist.h | 1 + tests/Makefile.am | 3 ++ tests/cavern.tst | 3 +- tests/csprj.out | 24 ++++++++++ tests/csprj.pos | 4 ++ tests/csprj.prj | 33 +++++++++++++ tests/csprj.svx | 11 +++++ tests/csprj2.out | 24 ++++++++++ tests/csprj2.pos | 4 ++ tests/csprj2.prj | 33 +++++++++++++ tests/csprj2.svx | 11 +++++ tests/csprjbad.out | 30 ++++++++++++ tests/csprjbad.svx | 8 ++++ 16 files changed, 343 insertions(+), 5 deletions(-) create mode 100644 tests/csprj.out create mode 100644 tests/csprj.pos create mode 100644 tests/csprj.prj create mode 100644 tests/csprj.svx create mode 100644 tests/csprj2.out create mode 100644 tests/csprj2.pos create mode 100644 tests/csprj2.prj create mode 100644 tests/csprj2.svx create mode 100644 tests/csprjbad.out create mode 100644 tests/csprjbad.svx diff --git a/doc/3dformat.htm b/doc/3dformat.htm index b6e8ab42..17546c91 100644 --- a/doc/3dformat.htm +++ b/doc/3dformat.htm @@ -60,7 +60,14 @@ There's no length limit on this string. which can be passed to PROJ. For a coordinate system with an EPSG code EPSG: followed by the code number can be used (we recommend using this if an EPSG code exists). Similarly, an ESRI code can be specified -with ESRI: followed by the code number. +with ESRI: followed by the code number. Any other description +PROJ accepts may be used, such as a PROJ string, WKT or PROJJSON - this is how +a coordinate system based on a datum PROJ has no +datum= keyword +for gets recorded. Since the metadata ends at a linefeed, the string must be +written on a single line - WKT and PROJJSON are usually pretty printed over +several lines, so a writer needs to join those lines (a single space in place +of each line break works, as neither format allows a newline inside a quoted +name).
  • Survey hierarchy separator character. Survey station names form a hierarchy, and this character separates levels in the hierarchy. E.g. 161.entrance.6. Defaults to . if this item is not diff --git a/doc/datafile.rst b/doc/datafile.rst index 57952747..45b6b06e 100644 --- a/doc/datafile.rst +++ b/doc/datafile.rst @@ -501,6 +501,11 @@ Example ; Output in the coordinate system used in the Totes Gebirge in Austria *cs out custom "+proj=tmerc +lat_0=0 +lon_0=13d20 +k=1 +x_0=0 +y_0=-5200000 +ellps=bessel +towgs84=577.326,90.129,463.919,5.137,1.474,5.297,2.4232" + :: + + ; Output in a low distortion projection described by mammoth.prj + *cs out custom @mammoth.prj + Description ``*cs`` allows the coordinate systems used for fixed points and for processed survey data to be specified. @@ -529,7 +534,35 @@ Description resource for finding the EPSG code you want. For example, ``EPSG:4167`` is NZGD2000. Supported since Survex 1.2.15. - * ``CUSTOM`` followed by a PROJ string (like in the example above). + * ``CUSTOM`` followed by a PROJ string, or by ``@`` and the name of a file + containing a description of the coordinate system - the last two examples + above show each of these in turn. + + Such a file may contain a PROJ string, but the point of it is that it can + also hold WKT or PROJJSON, which are made up of double quoted strings + written over several lines and so are awkward to write in a ``.svx`` + file. This means a ``.prj`` file such as those which accompany ESRI + shapefiles can be used directly, so you can georeference a survey to match + GIS data you already have. + + It's worth using WKT when the datum you need is one PROJ has no + ``+datum=`` keyword for, which is the case for most datums in current use + (such as NAD83(2011), ETRS89 and GDA2020). A PROJ string can only express + a datum as an ellipsoid plus a static shift, so PROJ quietly drops such a + datum when it converts a coordinate system to a PROJ string. + + The filename is relative to the directory containing the file the ``*cs`` + command is in, and an extension of ``.prj`` is assumed if the name as + given doesn't exist. Use double quotes around the name if it contains + spaces - the ``@`` may go either side of the opening quote, so both + ``@"My Cave.prj"`` and ``"@My Cave.prj"`` work. + + The lines of the file are joined together with a single space, since the + coordinate system is stored in the ``.3d`` file as a single line. This + only affects whitespace which the formats treat as insignificant, because + neither WKT nor PROJJSON allows a newline inside a quoted name. + + Reading the coordinate system from a file was added in Survex 1.4.23. * ``ESRI:`` followed by a positive integer code. ESRI codes are used by ArcGIS to specify coordinate systems (in a similar way to EPSG codes) diff --git a/src/commands.c b/src/commands.c index 5834a3d2..f826f0bf 100644 --- a/src/commands.c +++ b/src/commands.c @@ -33,6 +33,7 @@ #include "datain.h" #include "date.h" #include "debug.h" +#include "filelist.h" #include "filename.h" #include "message.h" #include "netbits.h" @@ -2486,6 +2487,92 @@ static const sztok cs_tab[] = { {NULL, CS_NONE} }; +/* Read a coordinate system from the file FNM, as specified by + * `*cs custom @FILENAME`. FP is the position of FILENAME in the current file, + * which any diagnostic is reported against. + * + * WKT and PROJJSON are made up of double quoted strings and are usually + * written over several lines, which makes them awkward to write in a .svx + * file. Keeping such a description in its own file also means a .prj file + * such as those which accompany ESRI shapefiles can be used directly. + * + * Returns the coordinate system description, or NULL if the file couldn't be + * opened (in which case a diagnostic has been reported). + */ +static char * +read_cs_from_file(const char *fnm, const filepos *fp) +{ + char *pth = path_from_fnm(file.filename); + char *fnm_used = NULL; + FILE *fh = fopen_portable(pth, fnm, EXT_PRJ, "rb", &fnm_used); + free(pth); + if (fh == NULL) { + set_pos(fp); + compile_diagnostic(DIAG_ERR|DIAG_STRING, /*Couldn’t open file “%s”*/1, + fnm); + return NULL; + } + + int c = GETC(fh); + if (c == 0xef) { + /* Skip a UTF-8 "BOM" if there is one - PROJ rejects a description which + * starts with one. */ + if (GETC(fh) == 0xbb && GETC(fh) == 0xbf) { + c = GETC(fh); + } else { + rewind(fh); + c = GETC(fh); + } + } + + /* We store the coordinate system in the .3d file as part of a + * newline-terminated line, so it can't contain a newline. Join the lines + * with a single space, dropping blanks at the start and end of each line. + * Neither WKT nor PROJJSON allows a newline inside a quoted name, so only + * insignificant whitespace is affected. + */ + /* The s_clear() calls give each string a buffer, which for an empty file it + * would otherwise still lack by the time we use it - s_steal() writes the + * terminating zero byte to one, and s_appends() reads from one. + */ + string cs = S_INIT; + s_clear(&cs); + string blanks = S_INIT; + s_clear(&blanks); + bool line_break = false; + for ( ; c != EOF; c = GETC(fh)) { + if (c == '\n' || c == '\r') { + line_break = true; + s_clear(&blanks); + continue; + } + if (c == ' ' || c == '\t') { + /* Only keep blanks which turn out to be between two non-blanks on + * the same line. */ + if (cs.len) s_appendch(&blanks, c); + continue; + } + if (cs.len) { + if (line_break) { + s_appendch(&cs, ' '); + } else { + s_appends(&cs, &blanks); + } + } + s_clear(&blanks); + line_break = false; + s_appendch(&cs, c); + } + s_free(&blanks); + + if (FERROR(fh)) + fatalerror_in_file(fnm_used, 0, /*Error reading file*/18); + fclose(fh); + free(fnm_used); + + return s_steal(&cs); +} + static void cmd_cs(void) { @@ -2545,14 +2632,36 @@ cmd_cs(void) switch (cs) { case CS_NONE: break; - case CS_CUSTOM: + case CS_CUSTOM: { ok_for_output = MAYBE; + skipblanks(); + /* `@FILENAME` reads the coordinate system from a file. If FILENAME + * is quoted then the `@` may be written either side of the opening + * quote. + */ + bool from_file = (ch == '@'); + if (from_file) nextch(); get_pos(&fp); string str = S_INIT; read_string(&str); - proj_str = s_steal(&str); + const char *p = s_str(&str); + if (!from_file && *p == '@') { + from_file = true; + ++p; + } + if (from_file) { + proj_str = read_cs_from_file(p, &fp); + s_free(&str); + if (!proj_str) { + skipline(); + return; + } + } else { + proj_str = s_steal(&str); + } cs_sub = 0; break; + } case CS_EPSG: case CS_ESRI: ok_for_output = MAYBE; if (ch == ':' && isdigit(nextch())) { @@ -2766,6 +2875,7 @@ cmd_cs(void) /* Same as the current output projection, so valid for input. */ } else if (pcs->proj_str && strcmp(proj_str, pcs->proj_str) == 0) { /* Same as the current input projection, so nothing to do! */ + free(proj_str); return; } else if (ok_for_output == MAYBE) { /* (ok_for_output == MAYBE) also happens to indicate whether we need @@ -2779,6 +2889,7 @@ cmd_cs(void) proj_context_errno_string(PJ_DEFAULT_CTX, proj_context_errno(PJ_DEFAULT_CTX))); skipline(); + free(proj_str); return; } proj_destroy(pj); diff --git a/src/filelist.h b/src/filelist.h index 215cbbff..694d5d78 100644 --- a/src/filelist.h +++ b/src/filelist.h @@ -24,3 +24,4 @@ #define EXT_SVX_MSG "msg" #define EXT_INI "ini" #define EXT_LOG "log" +#define EXT_PRJ "prj" diff --git a/tests/Makefile.am b/tests/Makefile.am index 0fef3790..2f9aeb92 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -177,6 +177,9 @@ csbad.altout csbad.out csbad.svx\ csbadsdfix.altout csbadsdfix.out csbadsdfix.svx\ csfeet.out csfeet.pos csfeet.svx\ cslonglat.out cslonglat.svx\ +csprj.out csprj.pos csprj.prj csprj.svx\ +csprj2.out csprj2.pos csprj2.prj csprj2.svx\ +csprjbad.out csprjbad.svx\ omitfixaroundsolve.out omitfixaroundsolve.svx\ repeatreading.svx repeatreading.out repeatreading.pos\ mixedeols.out mixedeols.svx\ diff --git a/tests/cavern.tst b/tests/cavern.tst index 4b1d228b..5d2882bb 100755 --- a/tests/cavern.tst +++ b/tests/cavern.tst @@ -120,7 +120,8 @@ TESTS_= passage hanging_lrud equatenosuchstn surveytypo\ skipafterbadomit passagebad badreadingdotplus badcalibrate calibrate_clino\ badunits badbegin anonstn anonstnbad anonstnrev doubleinc reenterlots\ - cs csbad csbadsdfix csfeet cslonglat omitfixaroundsolve repeatreading\ + cs csbad csbadsdfix csfeet cslonglat csprj csprj2 csprjbad\ + omitfixaroundsolve repeatreading\ mixedeols utf8bom nonewlineateof suspectreadings cmd_data_default\ cmd_data_ignore\ quadrant_bearing bad_quadrant_bearing\ diff --git a/tests/csprj.out b/tests/csprj.out new file mode 100644 index 00000000..c4cb8d94 --- /dev/null +++ b/tests/csprj.out @@ -0,0 +1,24 @@ + +Removing trailing traverses... + +Concatenating traverses... + +Simplifying network... + +Calculating network... + +Calculating traverses... + +Calculating trailing traverses... + +Calculating statistics... + +Approximate full range of grid convergence: 0.0dg at entrance to 0.0dg at b +Survey contains 3 survey stations, joined by 2 legs. +There are 0 loops. +Total length of survey legs = 55.00m ( 55.00m adjusted) +Total plan length of survey legs = 54.87m +Total vertical length of survey legs = 3.49m +Vertical range = 2.61m (from entrance at 200.00m to a at 197.39m) +North-South range = 17.67m (from a at 1109.86m to b at 1092.19m) +East-West range = 47.55m (from b at 935.37m to entrance at 887.82m) diff --git a/tests/csprj.pos b/tests/csprj.pos new file mode 100644 index 00000000..b2af0f79 --- /dev/null +++ b/tests/csprj.pos @@ -0,0 +1,4 @@ +( Easting, Northing, Altitude ) +( 917.71, 1109.86, 197.39 ) a +( 935.37, 1092.19, 198.26 ) b +( 887.82, 1109.86, 200.00 ) entrance diff --git a/tests/csprj.prj b/tests/csprj.prj new file mode 100644 index 00000000..bb40c2e4 --- /dev/null +++ b/tests/csprj.prj @@ -0,0 +1,33 @@ +PROJCRS["Mammoth Cave LDP", + BASEGEOGCRS["NAD83(2011)", + DATUM["NAD83 (National Spatial Reference System 2011)", + ELLIPSOID["GRS 1980",6378137,298.257222101, + LENGTHUNIT["metre",1]]], + PRIMEM["Greenwich",0, + ANGLEUNIT["degree",0.0174532925199433]], + ID["EPSG",6318]], + CONVERSION["Transverse Mercator", + METHOD["Transverse Mercator", + ID["EPSG",9807]], + PARAMETER["Latitude of natural origin",37.1866, + ANGLEUNIT["degree",0.0174532925199433], + ID["EPSG",8801]], + PARAMETER["Longitude of natural origin",-86.1005, + ANGLEUNIT["degree",0.0174532925199433], + ID["EPSG",8802]], + PARAMETER["Scale factor at natural origin",1, + SCALEUNIT["unity",1], + ID["EPSG",8805]], + PARAMETER["False easting",0, + LENGTHUNIT["metre",1], + ID["EPSG",8806]], + PARAMETER["False northing",0, + LENGTHUNIT["metre",1], + ID["EPSG",8807]]], + CS[Cartesian,2], + AXIS["(E)",east, + ORDER[1], + LENGTHUNIT["metre",1]], + AXIS["(N)",north, + ORDER[2], + LENGTHUNIT["metre",1]]] diff --git a/tests/csprj.svx b/tests/csprj.svx new file mode 100644 index 00000000..a7cccb4b --- /dev/null +++ b/tests/csprj.svx @@ -0,0 +1,11 @@ +; pos=yes warn=0 +; Test *cs custom @FILENAME, which reads the coordinate system from a separate +; file. Here that's a low distortion projection for a cave, written as WKT +; over several lines - a PROJ string can't express the datum it's based on. +*cs EPSG:6318 +*cs out CUSTOM @csprj.prj + +*fix entrance -86.0905 37.1966 200 + +entrance a 30.0 090 -05 +a b 25.0 135 +02 diff --git a/tests/csprj2.out b/tests/csprj2.out new file mode 100644 index 00000000..cac0d37f --- /dev/null +++ b/tests/csprj2.out @@ -0,0 +1,24 @@ + +Removing trailing traverses... + +Concatenating traverses... + +Simplifying network... + +Calculating network... + +Calculating traverses... + +Calculating trailing traverses... + +Calculating statistics... + +Approximate full range of grid convergence: 0.0dg at entrance to 0.0dg at b +Survey contains 3 survey stations, joined by 2 legs. +There are 0 loops. +Total length of survey legs = 55.00m ( 55.00m adjusted) +Total plan length of survey legs = 54.87m +Total vertical length of survey legs = 3.49m +Vertical range = 2.61m (from entrance at 200.00m to a at 197.39m) +North-South range = 17.67m (from a at 41819.44m to b at 41801.78m) +East-West range = 47.55m (from b at 10891.01m to entrance at 10843.46m) diff --git a/tests/csprj2.pos b/tests/csprj2.pos new file mode 100644 index 00000000..7fb569af --- /dev/null +++ b/tests/csprj2.pos @@ -0,0 +1,4 @@ +( Easting, Northing, Altitude ) +( 10873.35, 41819.44, 197.39 ) a +( 10891.01, 41801.78, 198.26 ) b +( 10843.46, 41819.44, 200.00 ) entrance diff --git a/tests/csprj2.prj b/tests/csprj2.prj new file mode 100644 index 00000000..df9d4f2a --- /dev/null +++ b/tests/csprj2.prj @@ -0,0 +1,33 @@ +PROJCRS["Mammoth Cave LDP", + BASEGEOGCRS["NAD83(2011)", + DATUM["NAD83 (National Spatial Reference System 2011)", + ELLIPSOID["GRS 1980",6378137,298.257222101, + LENGTHUNIT["metre",1]]], + PRIMEM["Greenwich",0, + ANGLEUNIT["degree",0.0174532925199433]], + ID["EPSG",6318]], + CONVERSION["Mammoth Cave LDP TM", + METHOD["Transverse Mercator", + ID["EPSG",9807]], + PARAMETER["Latitude of natural origin",37, + ANGLEUNIT["degree",0.0174532925199433], + ID["EPSG",8801]], + PARAMETER["Longitude of natural origin",-86.1, + ANGLEUNIT["degree",0.0174532925199433], + ID["EPSG",8802]], + PARAMETER["Scale factor at natural origin",1.0000383, + SCALEUNIT["unity",1], + ID["EPSG",8805]], + PARAMETER["False easting",10000, + LENGTHUNIT["metre",1], + ID["EPSG",8806]], + PARAMETER["False northing",20000, + LENGTHUNIT["metre",1], + ID["EPSG",8807]]], + CS[Cartesian,2], + AXIS["easting (E)",east, + ORDER[1], + LENGTHUNIT["metre",1]], + AXIS["northing (N)",north, + ORDER[2], + LENGTHUNIT["metre",1]]] diff --git a/tests/csprj2.svx b/tests/csprj2.svx new file mode 100644 index 00000000..9ae0d094 --- /dev/null +++ b/tests/csprj2.svx @@ -0,0 +1,11 @@ +; pos=yes warn=0 +; Test that *cs custom @FILENAME assumes a .prj extension if the name as given +; doesn't exist, and that a UTF-8 "BOM" at the start of the file is skipped. +; The coordinate system is quoted here too, with the `@` inside the quotes. +*cs EPSG:6318 +*cs out CUSTOM "@csprj2" + +*fix entrance -86.0905 37.1966 200 + +entrance a 30.0 090 -05 +a b 25.0 135 +02 diff --git a/tests/csprjbad.out b/tests/csprjbad.out new file mode 100644 index 00000000..e3aa2292 --- /dev/null +++ b/tests/csprjbad.out @@ -0,0 +1,30 @@ +./csprjbad.svx:4:17: error: Couldn't open file "nosuchfile.prj" + *cs out CUSTOM @nosuchfile.prj + ^~~~~~~~~~~~~~ +./csprjbad.svx:6: error: The input projection is set but the output projection isn't + *fix entrance -86.0905 37.1966 200 + +Removing trailing traverses... + +Concatenating traverses... + +Simplifying network... + +Calculating network... + +Calculating traverses... + +Calculating trailing traverses... + +Calculating statistics... + +Survey contains 2 survey stations, joined by 1 leg. +There are 0 loops. +Total length of survey legs = 30.00m ( 30.00m adjusted) +Total plan length of survey legs = 29.89m +Total vertical length of survey legs = 2.61m +Vertical range = 2.61m (from entrance at 200.00m to a at 197.39m) +North-South range = 0.00m (from a at 37.20m to a at 37.20m) +East-West range = 29.89m (from a at -56.20m to entrance at -86.09m) + +There were 0 warning(s) and 2 error(s) - no output files produced. diff --git a/tests/csprjbad.svx b/tests/csprjbad.svx new file mode 100644 index 00000000..8491a7fa --- /dev/null +++ b/tests/csprjbad.svx @@ -0,0 +1,8 @@ +; pos=fail error=2 +; Test the error from *cs custom @FILENAME naming a file which isn't there. +*cs EPSG:6318 +*cs out CUSTOM @nosuchfile.prj + +*fix entrance -86.0905 37.1966 200 + +entrance a 30.0 090 -05 -- 2.50.1 (Apple Git-155)