/src/gdal/frmts/dted/dted_create.c

Source
/******************************************************************************
 *
 * Project:  DTED Translator
 * Purpose:  Implementation of DTEDCreate() portion of DTED API.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2001, Frank Warmerdam
 *
 * SPDX-License-Identifier: MIT
 ****************************************************************************/

#include "dted_api.h"
#include <assert.h>

#define DTED_ABS_VERT_ACC "NA  "
#define DTED_SECURITY "U"
#define DTED_EDITION 1

/************************************************************************/
/*                           DTEDFormatDMS()                            */
/************************************************************************/

static void DTEDFormatDMS(unsigned char *achField, size_t nTargetLenSize,
                          size_t nOffset, double dfAngle,
                          const char *pszLatLong, const char *pszFormat)

{
    char chHemisphere;
    int nDegrees, nMinutes, nSeconds;
    double dfRemainder;

    if (pszFormat == NULL)
        pszFormat = "%03d%02d%02d%c";

    assert(EQUAL(pszLatLong, "LAT") || EQUAL(pszLatLong, "LONG"));

    if (EQUAL(pszLatLong, "LAT"))
    {
        if (dfAngle < 0.0)
            chHemisphere = 'S';
        else
            chHemisphere = 'N';
    }
    else
    {
        if (dfAngle < 0.0)
            chHemisphere = 'W';
        else
            chHemisphere = 'E';
    }

    dfAngle = CPL_ABS(dfAngle);

    nDegrees = (int)floor(dfAngle + 0.5 / 3600.0);
    dfRemainder = dfAngle - nDegrees;
    nMinutes = (int)floor(dfRemainder * 60.0 + 0.5 / 60.0);
    dfRemainder = dfRemainder - nMinutes / 60.0;
    nSeconds = (int)floor(dfRemainder * 3600.0 + 0.5);

    snprintf((char *)achField + nOffset, nTargetLenSize - nOffset, pszFormat,
             nDegrees, nMinutes, nSeconds, chHemisphere);
}

/************************************************************************/
/*                             DTEDFormat()                             */
/************************************************************************/

static void DTEDFormat(unsigned char *pszTarget, size_t nTargetLenSize,
                       size_t nOffset, const char *pszFormat, ...)
    CPL_PRINT_FUNC_FORMAT(4, 5);

static void DTEDFormat(unsigned char *pszTarget, size_t nTargetLenSize,
                       size_t nOffset, const char *pszFormat, ...)

{
    va_list args;

    va_start(args, pszFormat);
    CPLvsnprintf((char *)pszTarget + nOffset, nTargetLenSize - nOffset,
                 pszFormat, args);
    va_end(args);
}

/************************************************************************/
/*                             DTEDCreate()                             */
/************************************************************************/

const char *DTEDCreate(const char *pszFilename, int nLevel, int nLLOriginLat,
                       int nLLOriginLong)

{
    VSILFILE *fp;
    unsigned char achRecord[3601 * 2 + 12];
    int nXSize, nYSize, nReferenceLat, iProfile;

    /* -------------------------------------------------------------------- */
    /*      Establish resolution.                                           */
    /* -------------------------------------------------------------------- */
    if (nLevel == 0)
    {
        nXSize = 121;
        nYSize = 121;
    }
    else if (nLevel == 1)
    {
        nXSize = 1201;
        nYSize = 1201;
    }
    else if (nLevel == 2)
    {
        nXSize = 3601;
        nYSize = 3601;
    }
    else
    {
        return CPLSPrintf("Illegal DTED Level value %d, only 0-2 allowed.",
                          nLevel);
    }

    nReferenceLat = nLLOriginLat < 0 ? -(nLLOriginLat + 1) : nLLOriginLat;

    if (nReferenceLat >= 80)
        nXSize = (nXSize - 1) / 6 + 1;
    else if (nReferenceLat >= 75)
        nXSize = (nXSize - 1) / 4 + 1;
    else if (nReferenceLat >= 70)
        nXSize = (nXSize - 1) / 3 + 1;
    else if (nReferenceLat >= 50)
        nXSize = (nXSize - 1) / 2 + 1;

    /* -------------------------------------------------------------------- */
    /*      Open the file.                                                  */
    /* -------------------------------------------------------------------- */
    fp = VSIFOpenL(pszFilename, "wb");

    if (fp == NULL)
    {
        return CPLSPrintf("Unable to create file `%s'.", pszFilename);
    }

    /* -------------------------------------------------------------------- */
    /*      Format and write the UHL record.                                */
    /* -------------------------------------------------------------------- */
    memset(achRecord, ' ', DTED_UHL_SIZE);

    DTEDFormat(achRecord, sizeof(achRecord), 0, "UHL1");

    DTEDFormatDMS(achRecord, sizeof(achRecord), 4, nLLOriginLong, "LONG", NULL);
    DTEDFormatDMS(achRecord, sizeof(achRecord), 12, nLLOriginLat, "LAT", NULL);

    DTEDFormat(achRecord, sizeof(achRecord), 20, "%04d",
               (3600 / (nXSize - 1)) * 10);
    DTEDFormat(achRecord, sizeof(achRecord), 24, "%04d",
               (3600 / (nYSize - 1)) * 10);

    DTEDFormat(achRecord, sizeof(achRecord), 28, "%4s", DTED_ABS_VERT_ACC);
    DTEDFormat(achRecord, sizeof(achRecord), 32, "%-3s", DTED_SECURITY);
    DTEDFormat(achRecord, sizeof(achRecord), 47, "%04d", nXSize);
    DTEDFormat(achRecord, sizeof(achRecord), 51, "%04d", nYSize);
    DTEDFormat(achRecord, sizeof(achRecord), 55, "%c", '0');

    if (VSIFWriteL(achRecord, DTED_UHL_SIZE, 1, fp) != 1)
        return "UHL record write failed.";

    /* -------------------------------------------------------------------- */
    /*      Format and write the DSI record.                                */
    /* -------------------------------------------------------------------- */
    memset(achRecord, ' ', DTED_DSI_SIZE);

    DTEDFormat(achRecord, sizeof(achRecord), 0, "DSI");
    DTEDFormat(achRecord, sizeof(achRecord), 3, "%1s", DTED_SECURITY);

    DTEDFormat(achRecord, sizeof(achRecord), 59, "DTED%d", nLevel);
    DTEDFormat(achRecord, sizeof(achRecord), 64, "%015d", 0);
    DTEDFormat(achRecord, sizeof(achRecord), 87, "%02d", DTED_EDITION);
    DTEDFormat(achRecord, sizeof(achRecord), 89, "%c", 'A');
    DTEDFormat(achRecord, sizeof(achRecord), 90, "%04d", 0);
    DTEDFormat(achRecord, sizeof(achRecord), 94, "%04d", 0);
    DTEDFormat(achRecord, sizeof(achRecord), 98, "%04d", 0);
    DTEDFormat(achRecord, sizeof(achRecord), 126, "PRF89020B");
    DTEDFormat(achRecord, sizeof(achRecord), 135, "00");
    DTEDFormat(achRecord, sizeof(achRecord), 137, "0005");
    DTEDFormat(achRecord, sizeof(achRecord), 141, "MSL");
    DTEDFormat(achRecord, sizeof(achRecord), 144, "WGS84");

    /* origin */
    DTEDFormatDMS(achRecord, sizeof(achRecord), 185, nLLOriginLat, "LAT",
                  "%02d%02d%02d.0%c");
    DTEDFormatDMS(achRecord, sizeof(achRecord), 194, nLLOriginLong, "LONG",
                  "%03d%02d%02d.0%c");

    /* SW */
    DTEDFormatDMS(achRecord, sizeof(achRecord), 204, nLLOriginLat, "LAT",
                  "%02d%02d%02d%c");
    DTEDFormatDMS(achRecord, sizeof(achRecord), 211, nLLOriginLong, "LONG",
                  NULL);

    /* NW */
    DTEDFormatDMS(achRecord, sizeof(achRecord), 219, nLLOriginLat + 1, "LAT",
                  "%02d%02d%02d%c");
    DTEDFormatDMS(achRecord, sizeof(achRecord), 226, nLLOriginLong, "LONG",
                  NULL);

    /* NE */
    DTEDFormatDMS(achRecord, sizeof(achRecord), 234, nLLOriginLat + 1, "LAT",
                  "%02d%02d%02d%c");
    DTEDFormatDMS(achRecord, sizeof(achRecord), 241, nLLOriginLong + 1, "LONG",
                  NULL);

    /* SE */
    DTEDFormatDMS(achRecord, sizeof(achRecord), 249, nLLOriginLat, "LAT",
                  "%02d%02d%02d%c");
    DTEDFormatDMS(achRecord, sizeof(achRecord), 256, nLLOriginLong + 1, "LONG",
                  NULL);

    DTEDFormat(achRecord, sizeof(achRecord), 264, "0000000.0");
    DTEDFormat(achRecord, sizeof(achRecord), 264, "0000000.0");

    DTEDFormat(achRecord, sizeof(achRecord), 273, "%04d",
               (3600 / (nYSize - 1)) * 10);
    DTEDFormat(achRecord, sizeof(achRecord), 277, "%04d",
               (3600 / (nXSize - 1)) * 10);

    DTEDFormat(achRecord, sizeof(achRecord), 281, "%04d", nYSize);
    DTEDFormat(achRecord, sizeof(achRecord), 285, "%04d", nXSize);
    DTEDFormat(achRecord, sizeof(achRecord), 289, "%02d", 0);

    if (VSIFWriteL(achRecord, DTED_DSI_SIZE, 1, fp) != 1)
        return "DSI record write failed.";

    /* -------------------------------------------------------------------- */
    /*      Create and write ACC record.                                    */
    /* -------------------------------------------------------------------- */
    memset(achRecord, ' ', DTED_ACC_SIZE);

    DTEDFormat(achRecord, sizeof(achRecord), 0, "ACC");

    DTEDFormat(achRecord, sizeof(achRecord), 3, "NA");
    DTEDFormat(achRecord, sizeof(achRecord), 7, "NA");
    DTEDFormat(achRecord, sizeof(achRecord), 11, "NA");
    DTEDFormat(achRecord, sizeof(achRecord), 15, "NA");

    DTEDFormat(achRecord, sizeof(achRecord), 55, "00");

    if (VSIFWriteL(achRecord, DTED_ACC_SIZE, 1, fp) != 1)
        return "ACC record write failed.";

    /* -------------------------------------------------------------------- */
    /*      Write blank template profile data records.                      */
    /* -------------------------------------------------------------------- */
    memset(achRecord, 0, nYSize * 2 + 12);
    memset(achRecord + 8, 0xff, nYSize * 2);

    achRecord[0] = 0252;

    for (iProfile = 0; iProfile < nXSize; iProfile++)
    {
        achRecord[1] = 0;
        achRecord[2] = (GByte)(iProfile / 256);
        achRecord[3] = (GByte)(iProfile % 256);

        achRecord[4] = (GByte)(iProfile / 256);
        achRecord[5] = (GByte)(iProfile % 256);

        if (VSIFWriteL(achRecord, nYSize * 2 + 12, 1, fp) != 1)
            return "Data record write failed.";
    }

    if (VSIFCloseL(fp) != 0)
        return "I/O error";

    return NULL;
}

Coverage Report

Created: 2026-11-12 08:28

Line	Count	Source
1		/******************************************************************************
2		*
3		* Project: DTED Translator
4		* Purpose: Implementation of DTEDCreate() portion of DTED API.
5		* Author: Frank Warmerdam, warmerdam@pobox.com
6		*
7		******************************************************************************
8		* Copyright (c) 2001, Frank Warmerdam
9		*
10		* SPDX-License-Identifier: MIT
11		****************************************************************************/
12
13		#include "dted_api.h"
14		#include <assert.h>
15
16	0	#define DTED_ABS_VERT_ACC "NA "
17	0	#define DTED_SECURITY "U"
18	0	#define DTED_EDITION 1
19
20		/************************************************************************/
21		/* DTEDFormatDMS() */
22		/************************************************************************/
23
24		static void DTEDFormatDMS(unsigned char *achField, size_t nTargetLenSize,
25		size_t nOffset, double dfAngle,
26		const char pszLatLong, const char pszFormat)
27
28	0	{
29	0	char chHemisphere;
30	0	int nDegrees, nMinutes, nSeconds;
31	0	double dfRemainder;
32
33	0	if (pszFormat == NULL)
34	0	pszFormat = "%03d%02d%02d%c";
35
36	0	assert(EQUAL(pszLatLong, "LAT") \|\| EQUAL(pszLatLong, "LONG"));
37
38	0	if (EQUAL(pszLatLong, "LAT"))
39	0	{
40	0	if (dfAngle < 0.0)
41	0	chHemisphere = 'S';
42	0	else
43	0	chHemisphere = 'N';
44	0	}
45	0	else
46	0	{
47	0	if (dfAngle < 0.0)
48	0	chHemisphere = 'W';
49	0	else
50	0	chHemisphere = 'E';
51	0	}
52
53	0	dfAngle = CPL_ABS(dfAngle);
54
55	0	nDegrees = (int)floor(dfAngle + 0.5 / 3600.0);
56	0	dfRemainder = dfAngle - nDegrees;
57	0	nMinutes = (int)floor(dfRemainder * 60.0 + 0.5 / 60.0);
58	0	dfRemainder = dfRemainder - nMinutes / 60.0;
59	0	nSeconds = (int)floor(dfRemainder * 3600.0 + 0.5);
60
61	0	snprintf((char *)achField + nOffset, nTargetLenSize - nOffset, pszFormat,
62	0	nDegrees, nMinutes, nSeconds, chHemisphere);
63	0	}
64
65		/************************************************************************/
66		/* DTEDFormat() */
67		/************************************************************************/
68
69		static void DTEDFormat(unsigned char *pszTarget, size_t nTargetLenSize,
70		size_t nOffset, const char *pszFormat, ...)
71		CPL_PRINT_FUNC_FORMAT(4, 5);
72
73		static void DTEDFormat(unsigned char *pszTarget, size_t nTargetLenSize,
74		size_t nOffset, const char *pszFormat, ...)
75
76	0	{
77	0	va_list args;
78
79	0	va_start(args, pszFormat);
80	0	CPLvsnprintf((char *)pszTarget + nOffset, nTargetLenSize - nOffset,
81	0	pszFormat, args);
82	0	va_end(args);
83	0	}
84
85		/************************************************************************/
86		/* DTEDCreate() */
87		/************************************************************************/
88
89		const char DTEDCreate(const char pszFilename, int nLevel, int nLLOriginLat,
90		int nLLOriginLong)
91
92	0	{
93	0	VSILFILE *fp;
94	0	unsigned char achRecord[3601 * 2 + 12];
95	0	int nXSize, nYSize, nReferenceLat, iProfile;
96
97		/* -------------------------------------------------------------------- */
98		/* Establish resolution. */
99		/* -------------------------------------------------------------------- */
100	0	if (nLevel == 0)
101	0	{
102	0	nXSize = 121;
103	0	nYSize = 121;
104	0	}
105	0	else if (nLevel == 1)
106	0	{
107	0	nXSize = 1201;
108	0	nYSize = 1201;
109	0	}
110	0	else if (nLevel == 2)
111	0	{
112	0	nXSize = 3601;
113	0	nYSize = 3601;
114	0	}
115	0	else
116	0	{
117	0	return CPLSPrintf("Illegal DTED Level value %d, only 0-2 allowed.",
118	0	nLevel);
119	0	}
120
121	0	nReferenceLat = nLLOriginLat < 0 ? -(nLLOriginLat + 1) : nLLOriginLat;
122
123	0	if (nReferenceLat >= 80)
124	0	nXSize = (nXSize - 1) / 6 + 1;
125	0	else if (nReferenceLat >= 75)
126	0	nXSize = (nXSize - 1) / 4 + 1;
127	0	else if (nReferenceLat >= 70)
128	0	nXSize = (nXSize - 1) / 3 + 1;
129	0	else if (nReferenceLat >= 50)
130	0	nXSize = (nXSize - 1) / 2 + 1;
131
132		/* -------------------------------------------------------------------- */
133		/* Open the file. */
134		/* -------------------------------------------------------------------- */
135	0	fp = VSIFOpenL(pszFilename, "wb");
136
137	0	if (fp == NULL)
138	0	{
139	0	return CPLSPrintf("Unable to create file `%s'.", pszFilename);
140	0	}
141
142		/* -------------------------------------------------------------------- */
143		/* Format and write the UHL record. */
144		/* -------------------------------------------------------------------- */
145	0	memset(achRecord, ' ', DTED_UHL_SIZE);
146
147	0	DTEDFormat(achRecord, sizeof(achRecord), 0, "UHL1");
148
149	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 4, nLLOriginLong, "LONG", NULL);
150	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 12, nLLOriginLat, "LAT", NULL);
151
152	0	DTEDFormat(achRecord, sizeof(achRecord), 20, "%04d",
153	0	(3600 / (nXSize - 1)) * 10);
154	0	DTEDFormat(achRecord, sizeof(achRecord), 24, "%04d",
155	0	(3600 / (nYSize - 1)) * 10);
156
157	0	DTEDFormat(achRecord, sizeof(achRecord), 28, "%4s", DTED_ABS_VERT_ACC);
158	0	DTEDFormat(achRecord, sizeof(achRecord), 32, "%-3s", DTED_SECURITY);
159	0	DTEDFormat(achRecord, sizeof(achRecord), 47, "%04d", nXSize);
160	0	DTEDFormat(achRecord, sizeof(achRecord), 51, "%04d", nYSize);
161	0	DTEDFormat(achRecord, sizeof(achRecord), 55, "%c", '0');
162
163	0	if (VSIFWriteL(achRecord, DTED_UHL_SIZE, 1, fp) != 1)
164	0	return "UHL record write failed.";
165
166		/* -------------------------------------------------------------------- */
167		/* Format and write the DSI record. */
168		/* -------------------------------------------------------------------- */
169	0	memset(achRecord, ' ', DTED_DSI_SIZE);
170
171	0	DTEDFormat(achRecord, sizeof(achRecord), 0, "DSI");
172	0	DTEDFormat(achRecord, sizeof(achRecord), 3, "%1s", DTED_SECURITY);
173
174	0	DTEDFormat(achRecord, sizeof(achRecord), 59, "DTED%d", nLevel);
175	0	DTEDFormat(achRecord, sizeof(achRecord), 64, "%015d", 0);
176	0	DTEDFormat(achRecord, sizeof(achRecord), 87, "%02d", DTED_EDITION);
177	0	DTEDFormat(achRecord, sizeof(achRecord), 89, "%c", 'A');
178	0	DTEDFormat(achRecord, sizeof(achRecord), 90, "%04d", 0);
179	0	DTEDFormat(achRecord, sizeof(achRecord), 94, "%04d", 0);
180	0	DTEDFormat(achRecord, sizeof(achRecord), 98, "%04d", 0);
181	0	DTEDFormat(achRecord, sizeof(achRecord), 126, "PRF89020B");
182	0	DTEDFormat(achRecord, sizeof(achRecord), 135, "00");
183	0	DTEDFormat(achRecord, sizeof(achRecord), 137, "0005");
184	0	DTEDFormat(achRecord, sizeof(achRecord), 141, "MSL");
185	0	DTEDFormat(achRecord, sizeof(achRecord), 144, "WGS84");
186
187		/* origin */
188	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 185, nLLOriginLat, "LAT",
189	0	"%02d%02d%02d.0%c");
190	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 194, nLLOriginLong, "LONG",
191	0	"%03d%02d%02d.0%c");
192
193		/* SW */
194	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 204, nLLOriginLat, "LAT",
195	0	"%02d%02d%02d%c");
196	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 211, nLLOriginLong, "LONG",
197	0	NULL);
198
199		/* NW */
200	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 219, nLLOriginLat + 1, "LAT",
201	0	"%02d%02d%02d%c");
202	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 226, nLLOriginLong, "LONG",
203	0	NULL);
204
205		/* NE */
206	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 234, nLLOriginLat + 1, "LAT",
207	0	"%02d%02d%02d%c");
208	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 241, nLLOriginLong + 1, "LONG",
209	0	NULL);
210
211		/* SE */
212	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 249, nLLOriginLat, "LAT",
213	0	"%02d%02d%02d%c");
214	0	DTEDFormatDMS(achRecord, sizeof(achRecord), 256, nLLOriginLong + 1, "LONG",
215	0	NULL);
216
217	0	DTEDFormat(achRecord, sizeof(achRecord), 264, "0000000.0");
218	0	DTEDFormat(achRecord, sizeof(achRecord), 264, "0000000.0");
219
220	0	DTEDFormat(achRecord, sizeof(achRecord), 273, "%04d",
221	0	(3600 / (nYSize - 1)) * 10);
222	0	DTEDFormat(achRecord, sizeof(achRecord), 277, "%04d",
223	0	(3600 / (nXSize - 1)) * 10);
224
225	0	DTEDFormat(achRecord, sizeof(achRecord), 281, "%04d", nYSize);
226	0	DTEDFormat(achRecord, sizeof(achRecord), 285, "%04d", nXSize);
227	0	DTEDFormat(achRecord, sizeof(achRecord), 289, "%02d", 0);
228
229	0	if (VSIFWriteL(achRecord, DTED_DSI_SIZE, 1, fp) != 1)
230	0	return "DSI record write failed.";
231
232		/* -------------------------------------------------------------------- */
233		/* Create and write ACC record. */
234		/* -------------------------------------------------------------------- */
235	0	memset(achRecord, ' ', DTED_ACC_SIZE);
236
237	0	DTEDFormat(achRecord, sizeof(achRecord), 0, "ACC");
238
239	0	DTEDFormat(achRecord, sizeof(achRecord), 3, "NA");
240	0	DTEDFormat(achRecord, sizeof(achRecord), 7, "NA");
241	0	DTEDFormat(achRecord, sizeof(achRecord), 11, "NA");
242	0	DTEDFormat(achRecord, sizeof(achRecord), 15, "NA");
243
244	0	DTEDFormat(achRecord, sizeof(achRecord), 55, "00");
245
246	0	if (VSIFWriteL(achRecord, DTED_ACC_SIZE, 1, fp) != 1)
247	0	return "ACC record write failed.";
248
249		/* -------------------------------------------------------------------- */
250		/* Write blank template profile data records. */
251		/* -------------------------------------------------------------------- */
252	0	memset(achRecord, 0, nYSize * 2 + 12);
253	0	memset(achRecord + 8, 0xff, nYSize * 2);
254
255	0	achRecord[0] = 0252;
256
257	0	for (iProfile = 0; iProfile < nXSize; iProfile++)
258	0	{
259	0	achRecord[1] = 0;
260	0	achRecord[2] = (GByte)(iProfile / 256);
261	0	achRecord[3] = (GByte)(iProfile % 256);
262
263	0	achRecord[4] = (GByte)(iProfile / 256);
264	0	achRecord[5] = (GByte)(iProfile % 256);
265
266	0	if (VSIFWriteL(achRecord, nYSize * 2 + 12, 1, fp) != 1)
267	0	return "Data record write failed.";
268	0	}
269
270	0	if (VSIFCloseL(fp) != 0)
271	0	return "I/O error";
272
273	0	return NULL;
274	0	}