// Contour plotter.
//
// Copyright (C) 1995, 2000, 2001 Maurice LeBrun
// Copyright (C) 2000, 2002 Joao Cardoso
// Copyright (C) 2000-2014 Alan W. Irwin
// Copyright (C) 2004 Andrew Ross
//
// This file is part of PLplot.
//
// PLplot is free software; you can redistribute it and/or modify
// it under the terms of the GNU Library General Public License as published
// by the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// PLplot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public License
// along with PLplot; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
//
#include "plplotP.h"
#ifdef MSDOS
#pragma optimize("",off)
#endif
// Static function prototypes.
static void
plcntr( PLF2EVAL_callback plf2eval, PLPointer plf2eval_data,
PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT flev, PLINT **ipts,
PLTRANSFORM_callback pltr, PLPointer pltr_data );
static void
pldrawcn( PLF2EVAL_callback plf2eval, PLPointer plf2eval_data,
PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT flev, char *flabel, PLINT kcol, PLINT krow,
PLFLT lastx, PLFLT lasty, PLINT startedge,
PLINT **ipts, PLFLT *distance, PLINT *lastindex,
PLTRANSFORM_callback pltr, PLPointer pltr_data );
static void
plfloatlabel( PLFLT value, char *string, PLINT len );
static PLFLT
plP_pcwcx( PLINT x );
static PLFLT
plP_pcwcy( PLINT y );
static void
pl_drawcontlabel( PLFLT tpx, PLFLT tpy, char *flabel, PLFLT *distance, PLINT *lastindex );
// Error flag for aborts
static int error;
//**************************************
//
// Defaults for contour label printing.
//
//**************************************
// Font height for contour labels (normalized)
static PLFLT
contlabel_size = 0.3;
// Offset of label from contour line (if set to 0.0, labels are printed on the lines).
static PLFLT
contlabel_offset = 0.006;
// Spacing parameter for contour labels
static PLFLT
contlabel_space = 0.1;
// Activate labels, default off
static PLINT
contlabel_active = 0;
// If the contour label exceed 10^(limexp) or 10^(-limexp), the exponential format is used
static PLINT
limexp = 4;
// Number of significant digits
static PLINT
sigprec = 2;
//******* contour lines storage ***************************
static CONT_LEVEL *startlev = NULL;
static CONT_LEVEL *currlev;
static CONT_LINE *currline;
static int cont3d = 0;
static CONT_LINE *
alloc_line( void )
{
CONT_LINE *line;
if ( ( line = (CONT_LINE *) malloc( sizeof ( CONT_LINE ) ) ) == NULL )
{
plexit( "alloc_line: Insufficient memory" );
}
line->x = (PLFLT *) malloc( LINE_ITEMS * sizeof ( PLFLT ) );
line->y = (PLFLT *) malloc( LINE_ITEMS * sizeof ( PLFLT ) );
if ( ( line->x == NULL ) || ( line->y == NULL ) )
{
plexit( "alloc_line: Insufficient memory" );
}
line->npts = 0;
line->next = NULL;
return line;
}
static CONT_LEVEL *
alloc_level( PLFLT level )
{
CONT_LEVEL *node;
if ( ( node = (CONT_LEVEL *) malloc( sizeof ( CONT_LEVEL ) ) ) == NULL )
{
plexit( "alloc_level: Insufficient memory" );
}
node->level = level;
node->next = NULL;
node->line = alloc_line( );
return node;
}
static void
realloc_line( CONT_LINE *line )
{
if ( ( ( line->x = (PLFLT *) realloc( line->x,
(size_t) ( line->npts + LINE_ITEMS ) * sizeof ( PLFLT ) ) ) == NULL ) ||
( ( line->y = (PLFLT *) realloc( line->y,
(size_t) ( line->npts + LINE_ITEMS ) * sizeof ( PLFLT ) ) ) == NULL ) )
plexit( "realloc_line: Insufficient memory" );
}
// new contour level
static void
cont_new_store( PLFLT level )
{
if ( cont3d )
{
if ( startlev == NULL )
{
startlev = alloc_level( level );
currlev = startlev;
}
else
{
currlev->next = alloc_level( level );
currlev = currlev->next;
}
currline = currlev->line;
}
}
void
cont_clean_store( CONT_LEVEL *ct )
{
CONT_LINE *tline, *cline;
CONT_LEVEL *tlev, *clevel;
if ( ct != NULL )
{
clevel = ct;
do
{
cline = clevel->line;
do
{
#ifdef CONT_PLOT_DEBUG
plP_movwor( cline->x[0], cline->y[0] );
for ( j = 1; j < cline->npts; j++ )
plP_drawor( cline->x[j], cline->y[j] );
#endif
tline = cline->next;
free( cline->x );
free( cline->y );
free( cline );
cline = tline;
}
while ( cline != NULL );
tlev = clevel->next;
free( clevel );
clevel = tlev;
}
while ( clevel != NULL );
startlev = NULL;
}
}
static void
cont_xy_store( PLFLT xx, PLFLT yy )
{
if ( cont3d )
{
PLINT pts = currline->npts;
if ( pts % LINE_ITEMS == 0 )
realloc_line( currline );
currline->x[pts] = xx;
currline->y[pts] = yy;
currline->npts++;
}
else
plP_drawor( xx, yy );
}
static void
cont_mv_store( PLFLT xx, PLFLT yy )
{
if ( cont3d )
{
if ( currline->npts != 0 ) // not an empty list, allocate new
{
currline->next = alloc_line( );
currline = currline->next;
}
// and fill first element
currline->x[0] = xx;
currline->y[0] = yy;
currline->npts = 1;
}
else
plP_movwor( xx, yy );
}
// small routine to set offset and spacing of contour labels, see desciption above
void c_pl_setcontlabelparam( PLFLT offset, PLFLT size, PLFLT spacing, PLINT active )
{
contlabel_offset = offset;
contlabel_size = size;
contlabel_space = spacing;
contlabel_active = active;
}
// small routine to set the format of the contour labels, description of limexp and prec see above
void c_pl_setcontlabelformat( PLINT lexp, PLINT sigdig )
{
limexp = lexp;
sigprec = sigdig;
}
static void pl_drawcontlabel( PLFLT tpx, PLFLT tpy, char *flabel, PLFLT *distance, PLINT *lastindex )
{
PLFLT delta_x, delta_y;
PLINT currx_old, curry_old;
delta_x = plP_pcdcx( plsc->currx ) - plP_pcdcx( plP_wcpcx( tpx ) );
delta_y = plP_pcdcy( plsc->curry ) - plP_pcdcy( plP_wcpcy( tpy ) );
currx_old = plsc->currx;
curry_old = plsc->curry;
*distance += sqrt( delta_x * delta_x + delta_y * delta_y );
plP_drawor( tpx, tpy );
if ( (int) ( fabs( *distance / contlabel_space ) ) > *lastindex )
{
PLFLT scale, vec_x, vec_y, mx, my, dev_x, dev_y, off_x, off_y;
vec_x = tpx - plP_pcwcx( currx_old );
vec_y = tpy - plP_pcwcy( curry_old );
// Ensure labels appear the right way up
if ( vec_x < 0 )
{
vec_x = -vec_x;
vec_y = -vec_y;
}
mx = (double) plsc->wpxscl / (double) plsc->phyxlen;
my = (double) plsc->wpyscl / (double) plsc->phyylen;
dev_x = -my * vec_y / mx;
dev_y = mx * vec_x / my;
scale = sqrt( ( mx * mx * dev_x * dev_x + my * my * dev_y * dev_y ) /
( contlabel_offset * contlabel_offset ) );
off_x = dev_x / scale;
off_y = dev_y / scale;
plptex( tpx + off_x, tpy + off_y, vec_x, vec_y, 0.5, flabel );
plP_movwor( tpx, tpy );
( *lastindex )++;
}
else
plP_movwor( tpx, tpy );
}
// Format contour labels. Arguments:
// value: floating point number to be formatted
// string: the formatted label, plptex must be called with it to actually
// print the label
//
static void plfloatlabel( PLFLT value, char *string, PLINT len )
{
PLINT setpre, precis;
// form[10] gives enough space for all non-malicious formats.
// tmpstring[15] gives enough room for 3 digits in a negative exponent
// or 4 digits in a positive exponent + null termination. That
// should be enough for all non-malicious use.
// Obviously there are security issues here that
// should be addressed as well.
//
#define FORM_LEN 10
#define TMPSTRING_LEN 15
char form[FORM_LEN], tmpstring[TMPSTRING_LEN];
PLINT exponent = 0;
PLFLT mant, tmp;
PLINT prec = sigprec;
plP_gprec( &setpre, &precis );
if ( setpre )
prec = precis;
if ( value > 0.0 )
tmp = log10( value );
else if ( value < 0.0 )
tmp = log10( -value );
else
tmp = 0;
if ( tmp >= 0.0 )
exponent = (int) tmp;
else if ( tmp < 0.0 )
{
tmp = -tmp;
if ( floor( tmp ) < tmp )
exponent = -(int) ( floor( tmp ) + 1.0 );
else
exponent = -(int) ( floor( tmp ) );
}
mant = value / pow( 10.0, exponent );
if ( mant != 0.0 )
mant = (int) ( mant * pow( 10.0, prec - 1 ) + 0.5 * mant / fabs( mant ) ) / pow( 10.0, prec - 1 );
snprintf( form, FORM_LEN, "%%.%df", prec - 1 );
snprintf( string, (size_t) len, form, mant );
snprintf( tmpstring, TMPSTRING_LEN, "#(229)10#u%d", exponent );
strncat( string, tmpstring, (size_t) len - strlen( string ) - 1 );
if ( abs( exponent ) < limexp || value == 0.0 )
{
value = pow( 10.0, exponent ) * mant;
if ( exponent >= 0 )
prec = prec - 1 - exponent;
else
prec = prec - 1 + abs( exponent );
if ( prec < 0 )
prec = 0;
snprintf( form, FORM_LEN, "%%.%df", (int) prec );
snprintf( string, (size_t) len, form, value );
}
}
// physical coords (x) to world coords
static PLFLT
plP_pcwcx( PLINT x )
{
return ( ( x - plsc->wpxoff ) / plsc->wpxscl );
}
// physical coords (y) to world coords
static PLFLT
plP_pcwcy( PLINT y )
{
return ( ( y - plsc->wpyoff ) / plsc->wpyscl );
}
//--------------------------------------------------------------------------
// plf2eval1()
//
// Does a lookup from a 2d function array. Array is of type (PLFLT **),
// and is column dominant (normal C ordering).
//--------------------------------------------------------------------------
PLFLT
plf2eval1( PLINT ix, PLINT iy, PLPointer plf2eval_data )
{
PLFLT value;
PLFLT **z = (PLFLT **) plf2eval_data;
value = z[ix][iy];
return value;
}
//--------------------------------------------------------------------------
// plf2eval2()
//
// Does a lookup from a 2d function array. plf2eval_data is treated as type
// (PLfGrid2 *).
//--------------------------------------------------------------------------
PLFLT
plf2eval2( PLINT ix, PLINT iy, PLPointer plf2eval_data )
{
PLFLT value;
PLfGrid2 *grid = (PLfGrid2 *) plf2eval_data;
value = grid->f[ix][iy];
return value;
}
//--------------------------------------------------------------------------
// plf2eval()
//
// Does a lookup from a 2d function array. Array is of type (PLFLT *), and
// is column dominant (normal C ordering). You MUST fill the ny maximum
// array index entry in the PLfGrid struct.
//--------------------------------------------------------------------------
PLFLT
plf2eval( PLINT ix, PLINT iy, PLPointer plf2eval_data )
{
PLFLT value;
PLfGrid *grid = (PLfGrid *) plf2eval_data;
value = grid->f[ix * grid->ny + iy];
return value;
}
//--------------------------------------------------------------------------
// plf2evalr()
//
// Does a lookup from a 2d function array. Array is of type (PLFLT *), and
// is row dominant (Fortran ordering). You MUST fill the nx maximum array
// index entry in the PLfGrid struct.
//--------------------------------------------------------------------------
PLFLT
plf2evalr( PLINT ix, PLINT iy, PLPointer plf2eval_data )
{
PLFLT value;
PLfGrid *grid = (PLfGrid *) plf2eval_data;
value = grid->f[ix + iy * grid->nx];
return value;
}
//--------------------------------------------------------------------------
//
// cont_store:
//
// Draw contour lines in memory.
// cont_clean_store() must be called after use to release allocated memory.
//
//--------------------------------------------------------------------------
void
cont_store( PLFLT_MATRIX f, PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT_VECTOR clevel, PLINT nlevel,
PLTRANSFORM_callback pltr, PLPointer pltr_data,
CONT_LEVEL **contour )
{
cont3d = 1;
plcont( f, nx, ny, kx, lx, ky, ly, clevel, nlevel,
pltr, pltr_data );
*contour = startlev;
cont3d = 0;
}
//--------------------------------------------------------------------------
// void plcont()
//
// Draws a contour plot from data in f(nx,ny). Is just a front-end to
// plfcont, with a particular choice for f2eval and f2eval_data.
//--------------------------------------------------------------------------
void
c_plcont( PLFLT_MATRIX f, PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT_VECTOR clevel, PLINT nlevel,
PLTRANSFORM_callback pltr, PLPointer pltr_data )
{
plfcont( plf2eval1, (PLPointer) f,
nx, ny, kx, lx, ky, ly, clevel, nlevel,
pltr, pltr_data );
}
//--------------------------------------------------------------------------
// void plfcont()
//
// Draws a contour plot using the function evaluator f2eval and data stored
// by way of the f2eval_data pointer. This allows arbitrary organizations
// of 2d array data to be used.
//
// The subrange of indices used for contouring is kx to lx in the x
// direction and from ky to ly in the y direction. The array of contour
// levels is clevel(nlevel), and "pltr" is the name of a function which
// transforms array indicies into world coordinates.
//
// Note that the fortran-like minimum and maximum indices (kx, lx, ky, ly)
// are translated into more C-like ones. I've only kept them as they are
// for the plfcont() argument list because of backward compatibility.
//--------------------------------------------------------------------------
void
plfcont( PLF2EVAL_callback f2eval, PLPointer f2eval_data,
PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT_VECTOR clevel, PLINT nlevel,
PLTRANSFORM_callback pltr, PLPointer pltr_data )
{
PLINT i, **ipts;
if ( pltr == NULL )
{
// If pltr is undefined, abort with an error.
plabort( "plfcont: The pltr callback must be defined" );
return;
}
if ( kx < 1 || kx >= lx )
{
plabort( "plfcont: indices must satisfy 1 <= kx <= lx <= nx" );
return;
}
if ( ky < 1 || ky >= ly )
{
plabort( "plfcont: indices must satisfy 1 <= ky <= ly <= ny" );
return;
}
if ( ( ipts = (PLINT **) malloc( (size_t) nx * sizeof ( PLINT * ) ) ) == NULL )
{
plexit( "plfcont: Insufficient memory" );
}
for ( i = 0; i < nx; i++ )
{
if ( ( ipts[i] = (PLINT *) malloc( (size_t) ny * sizeof ( PLINT * ) ) ) == NULL )
{
plexit( "plfcont: Insufficient memory" );
}
}
for ( i = 0; i < nlevel; i++ )
{
plcntr( f2eval, f2eval_data,
nx, ny, kx - 1, lx - 1, ky - 1, ly - 1, clevel[i], ipts,
pltr, pltr_data );
if ( error )
{
error = 0;
goto done;
}
}
done:
for ( i = 0; i < nx; i++ )
{
free( (void *) ipts[i] );
}
free( (void *) ipts );
}
//--------------------------------------------------------------------------
// void plcntr()
//
// The contour for a given level is drawn here. Note iscan has nx
// elements. ixstor and iystor each have nstor elements.
//--------------------------------------------------------------------------
static void
plcntr( PLF2EVAL_callback f2eval, PLPointer f2eval_data,
PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT flev, PLINT **ipts,
PLTRANSFORM_callback pltr, PLPointer pltr_data )
{
PLINT kcol, krow, lastindex;
PLFLT distance;
PLFLT save_def, save_scale;
char flabel[30];
plgchr( &save_def, &save_scale );
save_scale = save_scale / save_def;
cont_new_store( flev );
// format contour label for plptex and define the font height of the labels
plfloatlabel( flev, flabel, 30 );
plschr( 0.0, contlabel_size );
// Clear array for traversed squares
for ( kcol = kx; kcol < lx; kcol++ )
{
for ( krow = ky; krow < ly; krow++ )
{
ipts[kcol][krow] = 0;
}
}
for ( krow = ky; krow < ly; krow++ )
{
for ( kcol = kx; kcol < lx; kcol++ )
{
if ( ipts[kcol][krow] == 0 )
{
// Follow and draw a contour
pldrawcn( f2eval, f2eval_data,
nx, ny, kx, lx, ky, ly, flev, flabel, kcol, krow,
0.0, 0.0, -2, ipts, &distance, &lastindex,
pltr, pltr_data );
if ( error )
return;
}
}
}
plschr( save_def, save_scale );
}
//--------------------------------------------------------------------------
// void pldrawcn()
//
// Follow and draw a contour.
//--------------------------------------------------------------------------
static void
pldrawcn( PLF2EVAL_callback f2eval, PLPointer f2eval_data,
PLINT nx, PLINT ny, PLINT kx, PLINT lx,
PLINT ky, PLINT ly, PLFLT flev, char *flabel, PLINT kcol, PLINT krow,
PLFLT lastx, PLFLT lasty, PLINT startedge, PLINT **ipts,
PLFLT *distance, PLINT *lastindex,
PLTRANSFORM_callback pltr, PLPointer pltr_data )
{
PLFLT f[4];
PLFLT px[4], py[4], locx[4], locy[4];
PLINT iedge[4];
PLINT i, j, k, num, first, inext, kcolnext, krownext, sfi, sfj;
( *pltr )( kcol, krow + 1, &px[0], &py[0], pltr_data );
( *pltr )( kcol, krow, &px[1], &py[1], pltr_data );
( *pltr )( kcol + 1, krow, &px[2], &py[2], pltr_data );
( *pltr )( kcol + 1, krow + 1, &px[3], &py[3], pltr_data );
f[0] = f2eval( kcol, krow + 1, f2eval_data ) - flev;
f[1] = f2eval( kcol, krow, f2eval_data ) - flev;
f[2] = f2eval( kcol + 1, krow, f2eval_data ) - flev;
f[3] = f2eval( kcol + 1, krow + 1, f2eval_data ) - flev;
for ( i = 0, j = 1; i < 4; i++, j = ( j + 1 ) % 4 )
{
// Use intermediates to avoid possible floating point
// under / over flow during multiplication.
sfi = ( f[i] > 0.0 ) ? 1 : ( ( f[i] < 0.0 ) ? -1 : 0 );
sfj = ( f[j] > 0.0 ) ? 1 : ( ( f[j] < 0.0 ) ? -1 : 0 );
iedge[i] = ( sfi * sfj > 0 ) ? -1 : ( ( sfi * sfj < 0 ) ? 1 : 0 );
}
// Mark this square as done
ipts[kcol][krow] = 1;
// Check if no contour has been crossed i.e. iedge[i] = -1
if ( ( iedge[0] == -1 ) && ( iedge[1] == -1 ) && ( iedge[2] == -1 )
&& ( iedge[3] == -1 ) )
return;
// Check if this is a completely flat square - in which case
// ignore it
if ( ( f[0] == 0.0 ) && ( f[1] == 0.0 ) && ( f[2] == 0.0 ) &&
( f[3] == 0.0 ) )
return;
// Calculate intersection points
num = 0;
if ( startedge < 0 )
{
first = 1;
}
else
{
locx[num] = lastx;
locy[num] = lasty;
num++;
first = 0;
}
for ( k = 0, i = ( startedge < 0 ? 0 : startedge ); k < 4; k++, i = ( i + 1 ) % 4 )
{
if ( i == startedge )
continue;
// If the contour is an edge check it hasn't already been done
if ( f[i] == 0.0 && f[( i + 1 ) % 4] == 0.0 )
{
kcolnext = kcol;
krownext = krow;
if ( i == 0 )
kcolnext--;
if ( i == 1 )
krownext--;
if ( i == 2 )
kcolnext++;
if ( i == 3 )
krownext++;
if ( ( kcolnext < kx ) || ( kcolnext >= lx ) ||
( krownext < ky ) || ( krownext >= ly ) ||
( ipts[kcolnext][krownext] == 1 ) )
continue;
}
if ( ( iedge[i] == 1 ) || ( f[i] == 0.0 ) )
{
j = ( i + 1 ) % 4;
if ( f[i] != 0.0 )
{
locx[num] = ( px[i] * fabs( f[j] ) + px[j] * fabs( f[i] ) ) / fabs( f[j] - f[i] );
locy[num] = ( py[i] * fabs( f[j] ) + py[j] * fabs( f[i] ) ) / fabs( f[j] - f[i] );
}
else
{
locx[num] = px[i];
locy[num] = py[i];
}
// If this is the start of the contour then move to the point
if ( first == 1 )
{
cont_mv_store( locx[num], locy[num] );
first = 0;
*distance = 0;
*lastindex = 0;
}
else
{
// Link to the next point on the contour
if ( contlabel_active )
pl_drawcontlabel( locx[num], locy[num], flabel, distance, lastindex );
else
cont_xy_store( locx[num], locy[num] );
// Need to follow contour into next grid box
// Easy case where contour does not pass through corner
if ( f[i] != 0.0 )
{
kcolnext = kcol;
krownext = krow;
inext = ( i + 2 ) % 4;
if ( i == 0 )
kcolnext--;
if ( i == 1 )
krownext--;
if ( i == 2 )
kcolnext++;
if ( i == 3 )
krownext++;
if ( ( kcolnext >= kx ) && ( kcolnext < lx ) &&
( krownext >= ky ) && ( krownext < ly ) &&
( ipts[kcolnext][krownext] == 0 ) )
{
pldrawcn( f2eval, f2eval_data,
nx, ny, kx, lx, ky, ly, flev, flabel,
kcolnext, krownext,
locx[num], locy[num], inext, ipts,
distance, lastindex,
pltr, pltr_data );
}
}
// Hard case where contour passes through corner
// This is still not perfect - it may lose the contour
// which won't upset the contour itself (we can find it
// again later) but might upset the labelling
else
{
kcolnext = kcol;
krownext = krow;
inext = ( i + 2 ) % 4;
if ( i == 0 )
{
kcolnext--; krownext++;
}
if ( i == 1 )
{
krownext--; kcolnext--;
}
if ( i == 2 )
{
kcolnext++; krownext--;
}
if ( i == 3 )
{
krownext++; kcolnext++;
}
if ( ( kcolnext >= kx ) && ( kcolnext < lx ) &&
( krownext >= ky ) && ( krownext < ly ) &&
( ipts[kcolnext][krownext] == 0 ) )
{
pldrawcn( f2eval, f2eval_data,
nx, ny, kx, lx, ky, ly, flev, flabel,
kcolnext, krownext,
locx[num], locy[num], inext, ipts,
distance, lastindex,
pltr, pltr_data );
}
}
if ( first == 1 )
{
// Move back to first point
cont_mv_store( locx[num], locy[num] );
first = 0;
*distance = 0;
*lastindex = 0;
first = 0;
}
else
{
first = 1;
}
num++;
}
}
}
}
//--------------------------------------------------------------------------
// pltr0()
//
// Identity transformation.
//--------------------------------------------------------------------------
void
pltr0( PLFLT x, PLFLT y, PLFLT *tx, PLFLT *ty, PLPointer PL_UNUSED( pltr_data ) )
{
*tx = x;
*ty = y;
}
//--------------------------------------------------------------------------
// pltr1()
//
// Does linear interpolation from singly dimensioned coord arrays.
//
// Just abort for now if coordinates are out of bounds (don't think it's
// possible, but if so we could use linear extrapolation).
//--------------------------------------------------------------------------
void
pltr1( PLFLT x, PLFLT y, PLFLT *tx, PLFLT *ty, PLPointer pltr_data )
{
PLINT ul, ur, vl, vr;
PLFLT du, dv;
PLFLT xl, xr, yl, yr;
PLcGrid *grid = (PLcGrid *) pltr_data;
PLFLT *xg = grid->xg;
PLFLT *yg = grid->yg;
PLINT nx = grid->nx;
PLINT ny = grid->ny;
ul = (PLINT) x;
ur = ul + 1;
du = x - ul;
vl = (PLINT) y;
vr = vl + 1;
dv = y - vl;
if ( x < 0 || x > nx - 1 || y < 0 || y > ny - 1 )
{
plexit( "pltr1: Invalid coordinates" );
}
// Look up coordinates in row-dominant array.
// Have to handle right boundary specially -- if at the edge, we'd better
// not reference the out of bounds point.
//
xl = xg[ul];
yl = yg[vl];
if ( ur == nx )
{
*tx = xl;
}
else
{
xr = xg[ur];
*tx = xl * ( 1 - du ) + xr * du;
}
if ( vr == ny )
{
*ty = yl;
}
else
{
yr = yg[vr];
*ty = yl * ( 1 - dv ) + yr * dv;
}
}
//--------------------------------------------------------------------------
// pltr2()
//
// Does linear interpolation from doubly dimensioned coord arrays (column
// dominant, as per normal C 2d arrays).
//
// This routine includes lots of checks for out of bounds. This would occur
// occasionally due to some bugs in the contour plotter (now fixed). If an
// out of bounds coordinate is obtained, the boundary value is provided
// along with a warning. These checks should stay since no harm is done if
// if everything works correctly.
//--------------------------------------------------------------------------
void
pltr2( PLFLT x, PLFLT y, PLFLT *tx, PLFLT *ty, PLPointer pltr_data )
{
PLINT ul, ur, vl, vr;
PLFLT du, dv;
PLFLT xll, xlr, xrl, xrr;
PLFLT yll, ylr, yrl, yrr;
PLFLT xmin, xmax, ymin, ymax;
PLcGrid2 *grid = (PLcGrid2 *) pltr_data;
PLFLT **xg = grid->xg;
PLFLT **yg = grid->yg;
PLINT nx = grid->nx;
PLINT ny = grid->ny;
ul = (PLINT) x;
ur = ul + 1;
du = x - ul;
vl = (PLINT) y;
vr = vl + 1;
dv = y - vl;
xmin = 0;
xmax = nx - 1;
ymin = 0;
ymax = ny - 1;
if ( x < xmin || x > xmax || y < ymin || y > ymax )
{
plwarn( "pltr2: Invalid coordinates" );
if ( x < xmin )
{
if ( y < ymin )
{
*tx = xg[0][0];
*ty = yg[0][0];
}
else if ( y > ymax )
{
*tx = xg[0][ny - 1];
*ty = yg[0][ny - 1];
}
else
{
xll = xg[0][vl];
yll = yg[0][vl];
xlr = xg[0][vr];
ylr = yg[0][vr];
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
}
else if ( x > xmax )
{
if ( y < ymin )
{
*tx = xg[nx - 1][0];
*ty = yg[nx - 1][0];
}
else if ( y > ymax )
{
*tx = xg[nx - 1][ny - 1];
*ty = yg[nx - 1][ny - 1];
}
else
{
xll = xg[nx - 1][vl];
yll = yg[nx - 1][vl];
xlr = xg[nx - 1][vr];
ylr = yg[nx - 1][vr];
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
}
else
{
if ( y < ymin )
{
xll = xg[ul][0];
xrl = xg[ur][0];
yll = yg[ul][0];
yrl = yg[ur][0];
*tx = xll * ( 1 - du ) + xrl * ( du );
*ty = yll * ( 1 - du ) + yrl * ( du );
}
else if ( y > ymax )
{
xlr = xg[ul][ny - 1];
xrr = xg[ur][ny - 1];
ylr = yg[ul][ny - 1];
yrr = yg[ur][ny - 1];
*tx = xlr * ( 1 - du ) + xrr * ( du );
*ty = ylr * ( 1 - du ) + yrr * ( du );
}
}
}
// Normal case.
// Look up coordinates in row-dominant array.
// Have to handle right boundary specially -- if at the edge, we'd
// better not reference the out of bounds point.
//
else
{
xll = xg[ul][vl];
yll = yg[ul][vl];
// ur is out of bounds
if ( ur == nx && vr < ny )
{
xlr = xg[ul][vr];
ylr = yg[ul][vr];
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
// vr is out of bounds
else if ( ur < nx && vr == ny )
{
xrl = xg[ur][vl];
yrl = yg[ur][vl];
*tx = xll * ( 1 - du ) + xrl * ( du );
*ty = yll * ( 1 - du ) + yrl * ( du );
}
// both ur and vr are out of bounds
else if ( ur == nx && vr == ny )
{
*tx = xll;
*ty = yll;
}
// everything in bounds
else
{
xrl = xg[ur][vl];
xlr = xg[ul][vr];
xrr = xg[ur][vr];
yrl = yg[ur][vl];
ylr = yg[ul][vr];
yrr = yg[ur][vr];
*tx = xll * ( 1 - du ) * ( 1 - dv ) + xlr * ( 1 - du ) * ( dv ) +
xrl * ( du ) * ( 1 - dv ) + xrr * ( du ) * ( dv );
*ty = yll * ( 1 - du ) * ( 1 - dv ) + ylr * ( 1 - du ) * ( dv ) +
yrl * ( du ) * ( 1 - dv ) + yrr * ( du ) * ( dv );
}
}
}
//--------------------------------------------------------------------------
// pltr2p()
//
// Just like pltr2() but uses pointer arithmetic to get coordinates from 2d
// grid tables. This form of grid tables is compatible with those from
// PLplot 4.0. The grid data must be pointed to by a PLcGrid structure.
//--------------------------------------------------------------------------
void
pltr2p( PLFLT x, PLFLT y, PLFLT *tx, PLFLT *ty, PLPointer pltr_data )
{
PLINT ul, ur, vl, vr;
PLFLT du, dv;
PLFLT xll, xlr, xrl, xrr;
PLFLT yll, ylr, yrl, yrr;
PLFLT xmin, xmax, ymin, ymax;
PLcGrid *grid = (PLcGrid *) pltr_data;
PLFLT *xg = grid->xg;
PLFLT *yg = grid->yg;
PLINT nx = grid->nx;
PLINT ny = grid->ny;
ul = (PLINT) x;
ur = ul + 1;
du = x - ul;
vl = (PLINT) y;
vr = vl + 1;
dv = y - vl;
xmin = 0;
xmax = nx - 1;
ymin = 0;
ymax = ny - 1;
if ( x < xmin || x > xmax || y < ymin || y > ymax )
{
plwarn( "pltr2p: Invalid coordinates" );
if ( x < xmin )
{
if ( y < ymin )
{
*tx = *xg;
*ty = *yg;
}
else if ( y > ymax )
{
*tx = *( xg + ( ny - 1 ) );
*ty = *( yg + ( ny - 1 ) );
}
else
{
ul = 0;
xll = *( xg + ul * ny + vl );
yll = *( yg + ul * ny + vl );
xlr = *( xg + ul * ny + vr );
ylr = *( yg + ul * ny + vr );
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
}
else if ( x > xmax )
{
if ( y < ymin )
{
*tx = *( xg + ( ny - 1 ) * nx );
*ty = *( yg + ( ny - 1 ) * nx );
}
else if ( y > ymax )
{
*tx = *( xg + ( ny - 1 ) + ( nx - 1 ) * ny );
*ty = *( yg + ( ny - 1 ) + ( nx - 1 ) * ny );
}
else
{
ul = nx - 1;
xll = *( xg + ul * ny + vl );
yll = *( yg + ul * ny + vl );
xlr = *( xg + ul * ny + vr );
ylr = *( yg + ul * ny + vr );
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
}
else
{
if ( y < ymin )
{
vl = 0;
xll = *( xg + ul * ny + vl );
xrl = *( xg + ur * ny + vl );
yll = *( yg + ul * ny + vl );
yrl = *( yg + ur * ny + vl );
*tx = xll * ( 1 - du ) + xrl * ( du );
*ty = yll * ( 1 - du ) + yrl * ( du );
}
else if ( y > ymax )
{
vr = ny - 1;
xlr = *( xg + ul * ny + vr );
xrr = *( xg + ur * ny + vr );
ylr = *( yg + ul * ny + vr );
yrr = *( yg + ur * ny + vr );
*tx = xlr * ( 1 - du ) + xrr * ( du );
*ty = ylr * ( 1 - du ) + yrr * ( du );
}
}
}
// Normal case.
// Look up coordinates in row-dominant array.
// Have to handle right boundary specially -- if at the edge, we'd better
// not reference the out of bounds point.
//
else
{
xll = *( xg + ul * ny + vl );
yll = *( yg + ul * ny + vl );
// ur is out of bounds
if ( ur == nx && vr < ny )
{
xlr = *( xg + ul * ny + vr );
ylr = *( yg + ul * ny + vr );
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
// vr is out of bounds
else if ( ur < nx && vr == ny )
{
xrl = *( xg + ur * ny + vl );
yrl = *( yg + ur * ny + vl );
*tx = xll * ( 1 - du ) + xrl * ( du );
*ty = yll * ( 1 - du ) + yrl * ( du );
}
// both ur and vr are out of bounds
else if ( ur == nx && vr == ny )
{
*tx = xll;
*ty = yll;
}
// everything in bounds
else
{
xrl = *( xg + ur * ny + vl );
xlr = *( xg + ul * ny + vr );
xrr = *( xg + ur * ny + vr );
yrl = *( yg + ur * ny + vl );
ylr = *( yg + ul * ny + vr );
yrr = *( yg + ur * ny + vr );
*tx = xll * ( 1 - du ) * ( 1 - dv ) + xlr * ( 1 - du ) * ( dv ) +
xrl * ( du ) * ( 1 - dv ) + xrr * ( du ) * ( dv );
*ty = yll * ( 1 - du ) * ( 1 - dv ) + ylr * ( 1 - du ) * ( dv ) +
yrl * ( du ) * ( 1 - dv ) + yrr * ( du ) * ( dv );
}
}
}
//--------------------------------------------------------------------------
// pltr2f()
//
// Does linear interpolation from doubly dimensioned coord arrays
// (row dominant, i.e. Fortran ordering).
//
// This routine includes lots of checks for out of bounds. This would
// occur occasionally due to a bug in the contour plotter that is now fixed.
// If an out of bounds coordinate is obtained, the boundary value is provided
// along with a warning. These checks should stay since no harm is done if
// if everything works correctly.
//--------------------------------------------------------------------------
void
pltr2f( PLFLT x, PLFLT y, PLFLT *tx, PLFLT *ty, void *pltr_data )
{
PLINT ul, ur, vl, vr;
PLFLT du, dv;
PLFLT xll, xlr, xrl, xrr;
PLFLT yll, ylr, yrl, yrr;
PLFLT xmin, xmax, ymin, ymax;
PLcGrid *cgrid = (PLcGrid *) pltr_data;
PLFLT *xg = cgrid->xg;
PLFLT *yg = cgrid->yg;
PLINT nx = cgrid->nx;
PLINT ny = cgrid->ny;
ul = (PLINT) x;
ur = ul + 1;
du = x - ul;
vl = (PLINT) y;
vr = vl + 1;
dv = y - vl;
xmin = 0;
xmax = nx - 1;
ymin = 0;
ymax = ny - 1;
if ( x < xmin || x > xmax || y < ymin || y > ymax )
{
plwarn( "pltr2f: Invalid coordinates" );
if ( x < xmin )
{
if ( y < ymin )
{
*tx = *xg;
*ty = *yg;
}
else if ( y > ymax )
{
*tx = *( xg + ( ny - 1 ) * nx );
*ty = *( yg + ( ny - 1 ) * nx );
}
else
{
ul = 0;
xll = *( xg + ul + vl * nx );
yll = *( yg + ul + vl * nx );
xlr = *( xg + ul + vr * nx );
ylr = *( yg + ul + vr * nx );
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
}
else if ( x > xmax )
{
if ( y < ymin )
{
*tx = *( xg + ( nx - 1 ) );
*ty = *( yg + ( nx - 1 ) );
}
else if ( y > ymax )
{
*tx = *( xg + ( nx - 1 ) + ( ny - 1 ) * nx );
*ty = *( yg + ( nx - 1 ) + ( ny - 1 ) * nx );
}
else
{
ul = nx - 1;
xll = *( xg + ul + vl * nx );
yll = *( yg + ul + vl * nx );
xlr = *( xg + ul + vr * nx );
ylr = *( yg + ul + vr * nx );
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
}
else
{
if ( y < ymin )
{
vl = 0;
xll = *( xg + ul + vl * nx );
xrl = *( xg + ur + vl * nx );
yll = *( yg + ul + vl * nx );
yrl = *( yg + ur + vl * nx );
*tx = xll * ( 1 - du ) + xrl * ( du );
*ty = yll * ( 1 - du ) + yrl * ( du );
}
else if ( y > ymax )
{
vr = ny - 1;
xlr = *( xg + ul + vr * nx );
xrr = *( xg + ur + vr * nx );
ylr = *( yg + ul + vr * nx );
yrr = *( yg + ur + vr * nx );
*tx = xlr * ( 1 - du ) + xrr * ( du );
*ty = ylr * ( 1 - du ) + yrr * ( du );
}
}
}
// Normal case.
// Look up coordinates in row-dominant array.
// Have to handle right boundary specially -- if at the edge, we'd
// better not reference the out of bounds point.
else
{
xll = *( xg + ul + vl * nx );
yll = *( yg + ul + vl * nx );
// ur is out of bounds
if ( ur == nx && vr < ny )
{
xlr = *( xg + ul + vr * nx );
ylr = *( yg + ul + vr * nx );
*tx = xll * ( 1 - dv ) + xlr * ( dv );
*ty = yll * ( 1 - dv ) + ylr * ( dv );
}
// vr is out of bounds
else if ( ur < nx && vr == ny )
{
xrl = *( xg + ur + vl * nx );
yrl = *( yg + ur + vl * nx );
*tx = xll * ( 1 - du ) + xrl * ( du );
*ty = yll * ( 1 - du ) + yrl * ( du );
}
// both ur and vr are out of bounds
else if ( ur == nx && vr == ny )
{
*tx = xll;
*ty = yll;
}
// everything in bounds
else
{
xrl = *( xg + ur + vl * nx );
xlr = *( xg + ul + vr * nx );
xrr = *( xg + ur + vr * nx );
yrl = *( yg + ur + vl * nx );
ylr = *( yg + ul + vr * nx );
yrr = *( yg + ur + vr * nx );
*tx = xll * ( 1 - du ) * ( 1 - dv ) + xlr * ( 1 - du ) * ( dv ) +
xrl * ( du ) * ( 1 - dv ) + xrr * ( du ) * ( dv );
*ty = yll * ( 1 - du ) * ( 1 - dv ) + ylr * ( 1 - du ) * ( dv ) +
yrl * ( du ) * ( 1 - dv ) + yrr * ( du ) * ( dv );
}
}
}