pointcloud/lib/pc_util.c
Éric Lemoine 07c3ddd9f6 Prefix WKB API functions with pc_
This is to avoid conflicts with other libraries, like PostGIS.
2017-06-12 08:42:45 +02:00

418 lines
8.5 KiB
C

/***********************************************************************
* pc_util.c
*
* Handy functions used by the library.
*
* PgSQL Pointcloud is free and open source software provided
* by the Government of Canada
* Copyright (c) 2013 Natural Resources Canada
*
***********************************************************************/
#include "pc_api_internal.h"
#include <float.h>
/**********************************************************************************
* WKB AND ENDIANESS UTILITIES
*/
/* Our static character->number map. Anything > 15 is invalid */
static uint8_t hex2char[256] =
{
/* not Hex characters */
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
/* 0-9 */
0,1,2,3,4,5,6,7,8,9,20,20,20,20,20,20,
/* A-F */
20,10,11,12,13,14,15,20,20,20,20,20,20,20,20,20,
/* not Hex characters */
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
/* a-f */
20,10,11,12,13,14,15,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
/* not Hex characters (upper 128 characters) */
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,
20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20
};
uint8_t*
pc_bytes_from_hexbytes(const char *hexbuf, size_t hexsize)
{
uint8_t *buf = NULL;
register uint8_t h1, h2;
int i;
if( hexsize % 2 )
pcerror("Invalid hex string, length (%d) has to be a multiple of two!", hexsize);
buf = pcalloc(hexsize/2);
if( ! buf )
pcerror("Unable to allocate memory buffer.");
for( i = 0; i < hexsize/2; i++ )
{
h1 = hex2char[(int)hexbuf[2*i]];
h2 = hex2char[(int)hexbuf[2*i+1]];
if( h1 > 15 )
pcerror("Invalid hex character (%c) encountered", hexbuf[2*i]);
if( h2 > 15 )
pcerror("Invalid hex character (%c) encountered", hexbuf[2*i+1]);
/* First character is high bits, second is low bits */
buf[i] = ((h1 & 0x0F) << 4) | (h2 & 0x0F);
}
return buf;
}
static char *hexchr = "0123456789ABCDEF";
char*
pc_hexbytes_from_bytes(const uint8_t *bytebuf, size_t bytesize)
{
char *buf = pcalloc(2*bytesize + 1); /* 2 chars per byte + null terminator */
int i;
buf[2*bytesize] = '\0';
for ( i = 0; i < bytesize; i++ )
{
/* Top four bits to 0-F */
buf[2*i] = hexchr[bytebuf[i] >> 4];
/* Bottom four bits to 0-F */
buf[2*i+1] = hexchr[bytebuf[i] & 0x0F];
}
return buf;
}
/* 0 = xdr | big endian */
/* 1 = ndr | little endian */
char
machine_endian(void)
{
static int check_int = 1; /* dont modify this!!! */
return *((char *) &check_int);
}
int32_t
int32_flip_endian(int32_t val)
{
int i;
uint8_t tmp;
uint8_t b[4];
memcpy(b, &val, 4);
for ( i = 0; i < 2; i++ )
{
tmp = b[i];
b[i] = b[3-i];
b[3-i] = tmp;
}
memcpy(&val, b, 4);
return val;
}
int16_t
int16_flip_endian(int16_t val)
{
uint8_t tmp;
uint8_t b[2];
memcpy(b, &val, 2);
tmp = b[0];
b[0] = b[1];
b[1] = tmp;
memcpy(&val, b, 2);
return val;
}
int32_t
wkb_get_int32(const uint8_t *wkb, int flip_endian)
{
int32_t i;
memcpy(&i, wkb, 4);
if ( flip_endian )
return int32_flip_endian(i);
else
return i;
}
int16_t
wkb_get_int16(const uint8_t *wkb, int flip_endian)
{
int16_t i;
memcpy(&i, wkb, 2);
if ( flip_endian )
return int16_flip_endian(i);
else
return i;
}
uint8_t *
wkb_set_double(uint8_t *wkb, double d)
{
memcpy(wkb, &d, 8);
wkb += 8;
return wkb;
}
uint8_t *
wkb_set_uint32(uint8_t *wkb, uint32_t i)
{
memcpy(wkb, &i, 4);
wkb += 4;
return wkb;
}
uint8_t *
wkb_set_char(uint8_t *wkb, char c)
{
memcpy(wkb, &c, 1);
wkb += 1;
return wkb;
}
uint32_t
pc_wkb_get_pcid(const uint8_t *wkb)
{
/* We expect the bytes to be in WKB format for PCPOINT/PCPATCH */
/* byte 0: endian */
/* byte 1-4: pcid */
/* ...data... */
uint32_t pcid;
memcpy(&pcid, wkb + 1, 4);
if ( wkb[0] != machine_endian() )
{
pcid = int32_flip_endian(pcid);
}
return pcid;
}
uint32_t
wkb_get_compression(const uint8_t *wkb)
{
/* We expect the bytes to be in WKB format for PCPATCH */
/* byte 0: endian */
/* byte 1-4: pcid */
/* byte 5-8: compression */
/* ...data... */
uint32_t compression;
memcpy(&compression, wkb+1+4, 4);
if ( wkb[0] != machine_endian() )
{
compression = int32_flip_endian(compression);
}
return compression;
}
uint32_t
wkb_get_npoints(const uint8_t *wkb)
{
/* We expect the bytes to be in WKB format for PCPATCH */
/* byte 0: endian */
/* byte 1-4: pcid */
/* byte 5-8: compression */
/* byte 9-12: npoints */
/* ...data... */
uint32_t npoints;
memcpy(&npoints, wkb+1+4+4, 4);
if ( wkb[0] != machine_endian() )
{
npoints = int32_flip_endian(npoints);
}
return npoints;
}
uint8_t*
uncompressed_bytes_flip_endian(const uint8_t *bytebuf, const PCSCHEMA *schema, uint32_t npoints)
{
int i, j, k;
size_t bufsize = schema->size * npoints;
uint8_t *buf = pcalloc(bufsize);
memcpy(buf, bytebuf, bufsize);
for ( i = 0; i < npoints ; i++ )
{
for ( j = 0; j < schema->ndims; j++ )
{
PCDIMENSION *dimension = schema->dims[j];
uint8_t *ptr = buf + i * schema->size + dimension->byteoffset;
for ( k = 0; k < ((dimension->size)/2); k++ )
{
int l = dimension->size - k - 1;
uint8_t tmp = ptr[k];
ptr[k] = ptr[l];
ptr[l] = tmp;
}
}
}
return buf;
}
int
pc_bounds_intersects(const PCBOUNDS *b1, const PCBOUNDS *b2)
{
if ( b1->xmin > b2->xmax ||
b1->xmax < b2->xmin ||
b1->ymin > b2->ymax ||
b1->ymax < b2->ymin )
{
return PC_FALSE;
}
return PC_TRUE;
}
void
pc_bounds_init(PCBOUNDS *b)
{
b->xmin = b->ymin = DBL_MAX;
b->xmax = b->ymax = -1*DBL_MAX;
}
void pc_bounds_merge(PCBOUNDS *b1, const PCBOUNDS *b2)
{
if ( b2->xmin < b1->xmin ) b1->xmin = b2->xmin;
if ( b2->ymin < b1->ymin ) b1->ymin = b2->ymin;
if ( b2->xmax > b1->xmax ) b1->xmax = b2->xmax;
if ( b2->ymax > b1->ymax ) b1->ymax = b2->ymax;
}
static uint32_t srid_mask = 0x20000000;
static uint32_t m_mask = 0x40000000;
static uint32_t z_mask = 0x80000000;
uint8_t *
pc_bounding_diagonal_wkb_from_bounds(
const PCBOUNDS *bounds, const PCSCHEMA *schema, size_t *wkbsize)
{
uint8_t *wkb, *ptr;
uint32_t wkbtype;
size_t size;
wkbtype = 2; /* WKB LINESTRING */
size = 1 + 4 + 4 + (2 * 2 * 8); /* endian + type + npoints + 2 dbl pts */
if ( schema->srid != 0 )
{
wkbtype |= srid_mask;
size += 4;
}
wkb = pcalloc(size);
ptr = wkb;
ptr = wkb_set_char(ptr, machine_endian()); /* Endian flag */
ptr = wkb_set_uint32(ptr, wkbtype); /* Geometry type */
if ( schema->srid != 0 )
{
ptr = wkb_set_uint32(ptr, schema->srid); /* SRID */
}
ptr = wkb_set_uint32(ptr, 2); /* NPOINTS = 2 */
// point 1
ptr = wkb_set_double(ptr, bounds->xmin);
ptr = wkb_set_double(ptr, bounds->ymin);
// point 2
ptr = wkb_set_double(ptr, bounds->xmax);
ptr = wkb_set_double(ptr, bounds->ymax);
if ( wkbsize )
*wkbsize = size;
return wkb;
}
uint8_t *
pc_bounding_diagonal_wkb_from_stats(const PCSTATS *stats, size_t *wkbsize)
{
const PCSCHEMA *schema = stats->min.schema;
const PCPOINT *stat;
uint8_t *wkb, *ptr;
uint32_t wkbtype;
size_t size;
double val;
wkbtype = 2; /* WKB LINESTRING */
size = 1 + 4 + 4 + (2 * 2 * 8); /* endian + type + npoints + 2 dbl pts */
if ( schema->srid != 0 )
{
wkbtype |= srid_mask;
size += 4;
}
if ( schema->zdim )
{
wkbtype |= z_mask;
size += 2 * 8;
}
if ( schema->mdim )
{
wkbtype |= m_mask;
size += 2 * 8;
}
wkb = pcalloc(size);
ptr = wkb;
ptr = wkb_set_char(ptr, machine_endian()); /* Endian flag */
ptr = wkb_set_uint32(ptr, wkbtype); /* Geometry type */
if ( schema->srid != 0 )
{
ptr = wkb_set_uint32(ptr, schema->srid); /* SRID */
}
ptr = wkb_set_uint32(ptr, 2); /* NPOINTS = 2 */
// point 1
stat = &stats->min;
pc_point_get_x(stat, &val);
ptr = wkb_set_double(ptr, val);
pc_point_get_y(stat, &val);
ptr = wkb_set_double(ptr, val);
if ( schema->zdim )
{
pc_point_get_z(stat, &val);
ptr = wkb_set_double(ptr, val);
}
if ( schema->mdim )
{
pc_point_get_m(stat, &val);
ptr = wkb_set_double(ptr, val);
}
// point 2
stat = &stats->max;
pc_point_get_x(stat, &val);
ptr = wkb_set_double(ptr, val);
pc_point_get_y(stat, &val);
ptr = wkb_set_double(ptr, val);
if ( schema->zdim )
{
pc_point_get_z(stat, &val);
ptr = wkb_set_double(ptr, val);
}
if ( schema->mdim )
{
pc_point_get_m(stat, &val);
ptr = wkb_set_double(ptr, val);
}
if ( wkbsize )
*wkbsize = size;
return wkb;
}