Hi,

While testing plplot 5.11.1 with a map with polygons on Windows my application terminated due to a call to plabort. It was caused by calling plfill with n < 3. I investigated further on my Debian Stable system with a recent version of master [d71e48]. The bug is still present in this version.

Attached a modified x19.cc which calls plabort when drawing the map. In order to do so I replaced the cglobe.sh? files with the files in this archive [1] (854.21 KB). The first plot is fine, the seconds calls plabort.

I added a proof-of-concept fix, which also cleans up the duplicate tests in the if statements in drawmapdata. I'm not convinced this is the right approach. I still see glitches, but I'm not sure whether they are all caused by fact lines at the left hand side of the plot are sometimes omitted.


[1] http://www.naturalearthdata.com/http//www.naturalearthdata.com/download/50m/cultural/ne_50m_admin_0_countries_lakes.zip

Regards,
Mark de Wever
diff --git a/src/plmap.c b/src/plmap.c
index 4030512..a175e8d 100644
--- a/src/plmap.c
+++ b/src/plmap.c
@@ -149,17 +149,13 @@ drawmapdata( PLMAPFORM_callback mapform, int shapetype, PLINT n, PLFLT *x, PLFLT
     if ( mapform != NULL )
         ( *mapform )( n, x, y );
 
-    if ( shapetype == SHPT_ARC )
-        plline( n, x, y );
-    else if ( shapetype == SHPT_POINT )
-        for ( i = 0; i < n; ++i )
-            plptex( x[i], y[i], dx, dy, just, text );
-    else if ( shapetype == SHPT_POLYGON )
-        plfill( n, x, y );
-    else if ( shapetype == SHPT_ARCZ || shapetype == SHPT_ARCM )
+    if ( shapetype == SHPT_ARC || shapetype == SHPT_ARCZ || shapetype == SHPT_ARCM )
         plline( n, x, y );
     else if ( shapetype == SHPT_POLYGON || shapetype == SHPT_POLYGONZ || shapetype == SHPT_POLYGONM )
-        plfill( n, x, y );
+        if ( n == 2 )
+            plline( n, x, y );
+        else
+            plfill( n, x, y );
     else if ( shapetype == SHPT_POINT || shapetype == SHPT_POINTM || shapetype == SHPT_POINTZ )
         for ( i = 0; i < n; ++i )
             plptex( x[i], y[i], dx, dy, just, text );
//--------------------------------------------------------------------------
// $Id: x19.cc 12532 2013-09-26 15:18:37Z andrewross $
//--------------------------------------------------------------------------
//
//--------------------------------------------------------------------------
// Copyright (C) 2004  Andrew Ross
// Copyright (C) 2004  Alan W. Irwin
//
// 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; version 2 of the License.
//
// 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
//--------------------------------------------------------------------------
//
//--------------------------------------------------------------------------
// Implementation of PLplot example 19 in C++.
//--------------------------------------------------------------------------

#include "plc++demos.h"

#ifdef PL_USE_NAMESPACE
using namespace std;
#endif

class x19 {
public:
    x19( int, char ** );

private:
    // Class data
    plstream *pls;
};

void
map_transform( PLFLT x, PLFLT y, PLFLT *xt, PLFLT *yt, PLPointer /* data */ )
{
    PLFLT radius;

    radius = 90.0 - y;
    *xt    = radius * cos( x * M_PI / 180.0 );
    *yt    = radius * sin( x * M_PI / 180.0 );
}

//--------------------------------------------------------------------------
// mapform19
//
// Defines specific coordinate transformation for example 19.
// Not to be confused with mapform in src/plmap.c.
// x[], y[] are the coordinates to be plotted.
//--------------------------------------------------------------------------

void
mapform19( PLINT n, PLFLT *x, PLFLT *y )
{
    int   i;
    PLFLT xp, yp, radius;
    for ( i = 0; i < n; i++ )
    {
        radius = 90.0 - y[i];
        xp     = radius * cos( x[i] * M_PI / 180.0 );
        yp     = radius * sin( x[i] * M_PI / 180.0 );
        x[i]   = xp;
        y[i]   = yp;
    }
}

// "Normalize" longitude values so that they always fall between -180.0 and
// 180.0
PLFLT
normalize_longitude( PLFLT lon )
{
    PLFLT times;
    if ( lon >= -180.0 && lon <= 180.0 )
    {
        return ( lon );
    }
    else
    {
        times = floor( ( fabs( lon ) + 180.0 ) / 360.0 );
        if ( lon < 0.0 )
        {
            return ( lon + 360.0 * times );
        }
        else
        {
            return ( lon - 360.0 * times );
        }
    }
}

// A custom axis labeling function for longitudes and latitudes.
void
geolocation_labeler( PLINT axis, PLFLT value, char *label, PLINT length, 
PLPointer /* data */ )
{
    const char *direction_label = "";
    PLFLT      label_val        = 0.0;

    if ( axis == PL_Y_AXIS )
    {
        label_val = value;
        if ( label_val > 0.0 )
        {
            direction_label = " N";
        }
        else if ( label_val < 0.0 )
        {
            direction_label = " S";
        }
        else
        {
            direction_label = "Eq";
        }
    }
    else if ( axis == PL_X_AXIS )
    {
        label_val = normalize_longitude( value );
        if ( label_val > 0.0 )
        {
            direction_label = " E";
        }
        else if ( label_val < 0.0 )
        {
            direction_label = " W";
        }
        else
        {
            direction_label = "";
        }
    }
    if ( axis == PL_Y_AXIS && value == 0.0 )
    {
        // A special case for the equator
        snprintf( label, length, "%s", direction_label );
    }
    else
    {
        snprintf( label, length, "%.0f%s", fabs( label_val ), direction_label );
    }
}


x19::x19( int argc, char ** argv )
{
    PLFLT minx, maxx, miny, maxy;

    pls = new plstream();

    pls->parseopts( &argc, argv, PL_PARSE_FULL );

    pls->init();
    pls->col0( 1 );
    pls->slabelfunc( geolocation_labeler, NULL );

    miny = -90;
    maxy = 90;

    minx = -120;
    maxx = 238;

    pls->env( minx, maxx, miny, maxy, 1, 70 );
    pls->map( NULL, "cglobe", minx, maxx, miny, maxy );

        // Shift Abort
    minx += 20;
    maxx += 20;

    pls->env( minx, maxx, miny, maxy, 1, 70 );
    pls->map( NULL, "cglobe", minx, maxx, miny, maxy );

    delete pls;
}

int main( int argc, char ** argv )
{
    x19 *x = new x19( argc, argv );

    delete x;
}


//--------------------------------------------------------------------------
//                              End of x19.cc
//--------------------------------------------------------------------------
------------------------------------------------------------------------------
_______________________________________________
Plplot-devel mailing list
Plplot-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/plplot-devel

Reply via email to