// gcw-driver - PLplot Gnome Canvas Widget device driver.
//
// Copyright (C) 2004, 2005  Thomas J. Duck
// Copyright (C) 2004  Rafael Laboissiere
// All rights reserved.
//
//
// NOTICE
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
// USA
//
//
// DESCRIPTION
//
// This is the Gnome Canvas Widget driver, written by Thomas J. Duck
// following the heritage of the PLplot Gnome driver by Rafael Laboissiere.
// Like all PLplot drivers, this operates in standalone mode by default.
// However, this driver can also be used to write to a user-supplied
// GnomeCanvas.
//
// Please see the PLplot documentation for more information.
//
//
// DEVELOPMENT NOTES
//
// Truetype text is supplied using the PLPLOT_CANVAS_HACKTEXT item,
// which was cloned from gnome-print.  This text item was chosen because
// it rotates and scales under a zoom correctly and easily.
//
// It would be better to use GNOME_CANVAS_TEXT, but currently
// (4 March 2005) it doesn't rotate or scale under a zoom on the
// GnomeCanvas.  GNOME_CANVAS_TEXT uses Pango, and rotations were only
// recently implemented in the Pango API (i.e., Fall 2004).  If the
// Pango API is used directly, the bounding box doesn't rotate with the
// text on GnomeCanvas, which results in clipping.  It is likely that
// GnomeCanvas is not querying the bounding box from Pango correctly,
// and is not directing Pango to scale.  So, GnomeCanvas needs to be
// updated to deal with Pango properly.
//
// Another problem is that drawing polylines on the Gnome Canvas sometimes
// results in an 'attempt to put segment in horiz list twice' error.
// The workaround here is to plot single line segments only, but this
// results in a performance hit.  This problem will need to be corrected
// in the GnomeCanvas.
//
//
// KNOWN BUGS
//
// PLplot test suite problems:
//
//  1) Example x10c does not clip the text (there is no text clipping).
//
//  2) Example x17c, the strip chart demo, doesn't do a strip chart
//     (try the xwin driver to see how it should work).  Strip charts
//     are fundamentally incompatible with the tabbed window design of
//     the GCW driver.  Use the PlplotCanvas to create animations
//     instead.
//

#include <sys/stat.h>

#include "gcw.h"
#include "plplotcanvas-hacktext.h"

#ifdef PL_HAVE_FREETYPE

#include "plfreetype.h"
#include "plfci-truetype.h"

// Font lookup table that is constructed in plD_FreeType_init
extern FCI_to_FontName_Table FontLookup[N_TrueTypeLookup];

#endif // PL_HAVE_FREETYPE


// Device info
PLDLLIMPEXP_DRIVER const char* plD_DEVICE_INFO_gcw = "gcw:Gnome Canvas Widget:1:gcw:10:gcw\n";

// Global driver options

#ifdef PL_HAVE_FREETYPE
static PLINT text = 1;
#else
static PLINT text = 0;
#endif

static PLINT  hrshsym = 0;
static PLINT  replot  = 1;

static DrvOpt gcw_options[] =
{
    { "text",    DRV_INT, &text,    "Use truetype fonts (text=0|1)"                  },
    { "hrshsym", DRV_INT, &hrshsym, "Use Hershey symbol set (hrshsym=0|1)"           },
    { "replot",  DRV_INT, &replot,  "Allow replotting to other devices (replot=0|1)" },
    { NULL,      DRV_INT, NULL,     NULL                                             }
};


//********************
// Utility functions *
//*******************

guint32 plcolor_to_rgba( PLColor color, guchar alpha )
{
    return
        ( (int) ( color.r ) << 24 )
        + ( (int) ( color.g ) << 16 )
        + ( (int) ( color.b ) << 8 )
        + alpha;
}


//--------------------------------------------------------------------------
// plD_dispatch_init_gcw()
//
// Initializes the dispatch table.
//--------------------------------------------------------------------------

void plD_open_gcw( PLStream *pls );
void plD_init_gcw( PLStream * );
void plD_line_gcw( PLStream *, short, short, short, short );
void plD_polyline_gcw( PLStream *, short *, short *, PLINT );
void plD_eop_gcw( PLStream * );
void plD_bop_gcw( PLStream * );
void plD_tidy_gcw( PLStream * );
void plD_state_gcw( PLStream *, PLINT );
void plD_esc_gcw( PLStream *, PLINT, void * );

void plD_dispatch_init_gcw( PLDispatchTable *pdt )
{
#ifdef DEBUG_GCW_1
    gcw_debug( "<plD_dispatch_init_gcw>\n" );
#endif

#ifndef ENABLE_DYNDRIVERS
    pdt->pl_MenuStr = "Gnome Canvas Widget";
    pdt->pl_DevName = "gcw";
#endif
    pdt->pl_type     = plDevType_Interactive;
    pdt->pl_seq      = 1;
    pdt->pl_init     = (plD_init_fp) plD_init_gcw;
    pdt->pl_line     = (plD_line_fp) plD_line_gcw;
    pdt->pl_polyline = (plD_polyline_fp) plD_polyline_gcw;
    pdt->pl_eop      = (plD_eop_fp) plD_eop_gcw;
    pdt->pl_bop      = (plD_bop_fp) plD_bop_gcw;
    pdt->pl_tidy     = (plD_tidy_fp) plD_tidy_gcw;
    pdt->pl_state    = (plD_state_fp) plD_state_gcw;
    pdt->pl_esc      = (plD_esc_fp) plD_esc_gcw;

#ifdef DEBUG_GCW_1
    gcw_debug( "</plD_dispatch_init_gcw>\n" );
#endif
}


//--------------------------------------------------------------------------
// plD_init_gcw()
//
// Initializes the device.
//
// This routine is invoked by a call to plinit.
//
//--------------------------------------------------------------------------

void plD_init_gcw( PLStream *pls )
{
    GcwPLdev* dev;

    PLINT   width, height, tmp;

    PLColor bgcolor = pls->cmap0[0];

#ifdef DEBUG_GCW_1
    gcw_debug( "<plD_init_gcw>\n" );
#endif

    // Parse the driver options
    plParseDrvOpts( gcw_options );

    // Set up the stream
    pls->termin      = 1;      // Is an interactive terminal
    pls->dev_flush   = 1;      // Handle our own flushes
    pls->plbuf_write = replot; // Use plot buffer to replot to another device
    pls->width       = 1;
    pls->dev_clear   = 0;      // Handle plclear()
    pls->dev_fill0   = 1;      // Handle solid fills

    // Create the device
    if ( ( dev = g_malloc( sizeof ( GcwPLdev ) ) ) == NULL )
        plexit( "GCW driver <plD_init_gcw>: Cannot create device" );
    pls->dev = dev;

    // Set text handling
#ifdef PL_HAVE_FREETYPE
    if ( text )
    {
        pls->dev_text    = TRUE;
        pls->dev_unicode = TRUE;
        if ( hrshsym )
            pls->dev_hrshsym = 1;

        // Initialize freetype
        plD_FreeType_init( pls );
    }
    else
    {
        pls->dev_text    = FALSE;
        pls->dev_unicode = FALSE;
    }
#else
    pls->dev_text    = FALSE;
    pls->dev_unicode = FALSE;
#endif

    // Set up pixmap support
    dev->use_pixmap      = (gboolean) ( !pls->nopixmap );
    dev->pixmap_has_data = FALSE;

    // Initialize the device colors
    dev->color         = plcolor_to_rgba( pls->cmap0[pls->icol0], 0xFF );
    dev->bgcolor.red   = (guint16) ( bgcolor.r / 255. * 65535 );
    dev->bgcolor.green = (guint16) ( bgcolor.b / 255. * 65535 );
    dev->bgcolor.blue  = (guint16) ( bgcolor.g / 255. * 65535 );

    // Set the device canvas and window pointers
    dev->canvas     = NULL;
    dev->background = NULL;
    dev->gc         = NULL;
    dev->colormap   = NULL;
    dev->window     = NULL;
    dev->notebook   = NULL;
    dev->statusbar  = NULL;
    dev->filew      = NULL;

    // Initialize the Canvas groups.  All of the plplot plotting
    // commands are drawn to the hidden group.  When the page is finalized,
    // the group is made visible, and the old group destroyed. The persistent
    // group is never erased, and always plotted at the very front.
    //
    dev->group_visible    = NULL;
    dev->group_hidden     = NULL;
    dev->group_persistent = NULL;

    // Assume that pladv should completeley refresh the page
    dev->use_persistence = FALSE;

    // Set the initialization state monitors to FALSE
    dev->plstate_width  = FALSE;
    dev->plstate_color0 = FALSE;
    dev->plstate_color1 = FALSE;

    // Initialize gtk
    gtk_init( 0, NULL );

    // Set up the physical device in the next series of commands.  It is very
    // important to do this properly, because many PLplot routines depend on
    // physical coordinates (e.g., dashed lines, hatched areas, the
    // replot mechanism, hidden line removal, etc.
    //
    // Note that coordinates in the driver are measured in device units,
    // which correspond to the pixel size on a typical screen.  The coordinates
    // reported and received from the PLplot core, however, are in virtual
    // coordinates, which is just a scaled version of the device coordinates.
    // This strategy is used so that the calculations in the PLplot
    // core are performed at reasonably high resolution.
    //
    //
    if ( pls->xlength > 0 && pls->ylength > 0 )
    {
        // xlength and length are the dimensions specified using -geometry
        // on the command line, in device coordinates.
        //
        width  = pls->xlength;
        height = pls->ylength;
    }
    else
    {
        width  = (PLINT) ( CANVAS_WIDTH * DEVICE_PIXELS_PER_IN );
        height = (PLINT) ( CANVAS_HEIGHT * DEVICE_PIXELS_PER_IN );
    }

    // If portrait mode, apply a rotation and set freeaspect
    if ( pls->portrait )
    {
        plsdiori( (PLFLT) ( 4 - ORIENTATION ) );
        pls->freeaspect = 1;
    }

    // Setup the page size for this device.  Very important for any driver!
    gcw_set_device_size( width, height );

    // Install a canvas... unless plsc->hack is set, which is a driver-specific
    // hack that indicates a PLESC_DEVINIT escape call will provide us with a
    // canvas to use.  This hack is used by the PlplotCanvas.
    //
    if ( !pls->hack )
    {
        dev->allow_resize = FALSE; // The size is set an should not be changed
        gcw_install_canvas( NULL );
    }
    else
        dev->allow_resize = TRUE;  // Resizing allowed for canvasses
                                   // provided via PLESC_DEVINIT


#ifdef DEBUG_GCW_1
    gcw_debug( "</plD_init_gcw>\n" );
#endif
}


//--------------------------------------------------------------------------
// plD_polyline_gcw()
//
// Draw a polyline in the current color.
//--------------------------------------------------------------------------

void plD_polyline_gcw( PLStream *pls, short *x, short *y, PLINT npts )
{
    GcwPLdev          * dev = pls->dev;
    GnomeCanvasPoints * points;
    GnomeCanvasPoints pts;
    GnomeCanvasGroup  * group;
    GnomeCanvasItem   * item;
    GnomeCanvas       * canvas;

    GdkPoint          * gdkpoints;

    PLINT             i;

    gdouble           width;
    guint32           color;

#ifdef DEBUG_GCW_2
    gcw_debug( "<plD_polyline_gcw />\n" );
#endif

    if ( !GNOME_IS_CANVAS( dev->canvas ) )
        plexit( "GCW driver <plD_polyline_gcw>: Canvas not found" );
    canvas = dev->canvas;

    if ( dev->use_persistence )
        group = dev->group_persistent;
    else
        group = dev->group_hidden;

    if ( dev->use_pixmap && !dev->use_persistence ) // Write to bg pixmap

    {
        if ( ( gdkpoints = (GdkPoint *) malloc( npts * sizeof ( GdkPoint ) ) ) == NULL )
        {
            plabort( "GCW driver <plD_polyline_gcw>: Could not create gdkpoints" );
            return;
        }

        if ( !pls->portrait )
        {
            for ( i = 0; i < npts; i++ )
            {
                gdkpoints[i].x = (gint) ( x[i] / VSCALE );
                gdkpoints[i].y = (gint) ( dev->height - y[i] / VSCALE );
            }
        }
        else // Swap x and y for portrait mode
        {
            for ( i = 0; i < npts; i++ )
            {
                gdkpoints[i].x = (gint) ( dev->height - y[i] / VSCALE );
                gdkpoints[i].y = (gint) ( dev->width - x[i] / VSCALE );
            }
        }

        gdk_draw_lines( dev->background, dev->gc, gdkpoints, npts );

        dev->pixmap_has_data = TRUE;

        free( gdkpoints );
    }
    else // Draw Canvas lines

    {
        // Put the data in a points structure
        if ( ( points = gnome_canvas_points_new( npts ) ) == NULL )
        {
            plabort( "GCW driver <plD_polyline_gcw>: Cannot create points" );
            return;
        }
        if ( !pls->portrait )
        {
            for ( i = 0; i < npts; i++ )
            {
                points->coords[2 * i]     = (gdouble) ( x[i] / VSCALE );
                points->coords[2 * i + 1] = (gdouble) ( -y[i] / VSCALE );
            }
        }
        else // Swap x and y for portrait mode
        {
            for ( i = 0; i < npts; i++ )
            {
                points->coords[2 * i]     = (gdouble) ( dev->height - y[i] / VSCALE );
                points->coords[2 * i + 1] = (gdouble) ( -x[i] / VSCALE );
            }
        }

        // Get the pen width and color
        width = pls->width;
        color = dev->color;


        // Workaround for the 'attempt to put segment in horiz list twice'
        // from libgnomecanvas:
        //
        //   Plot a series of line segments rather than a single polyline.
        //
        // This slows rendering down a considerable amount.  However, it is
        // unclear what else can be done.  Libgnomecanvas should be able to
        // deal with all valid data; bizarre plotting errors happen along with
        // this error.
        //
        // Note that instead of allocating a series of points structures,
        // we just refer to the original one from a separate struct
        // (GnomeCanvas does not hold a reference to the points structure).
        //

        pts.num_points = 2;
        pts.ref_count  = 1;
        pts.coords     = points->coords;

        for ( i = 0; i < npts - 1; i++ )
        {
            pts.coords = &( points->coords[2 * i] );

            if ( !GNOME_IS_CANVAS_ITEM(
                     item = gnome_canvas_item_new( group,
                         GNOME_TYPE_CANVAS_LINE,
                         "cap_style", GDK_CAP_ROUND,
                         "join-style", GDK_JOIN_ROUND,
                         "points", &pts,
                         "fill-color-rgba", color,
                         "width-units", width,
                         NULL )
                     ) )
            {
                plwarn( "GCW driver <plD_polyline_gcw>: Canvas item not created." );
            }
        }

        // Free the points structure
        gnome_canvas_points_free( points );
    }
}


//--------------------------------------------------------------------------
// plD_line_gcw()
//
// Draw a line in the current color from (x1,y1) to (x2,y2).
//--------------------------------------------------------------------------

void plD_line_gcw( PLStream *pls, short x1, short y1, short x2, short y2 )
{
    short x[2];
    short y[2];

#ifdef DEBUG_GCW_2
    gcw_debug( "<plD_line_gcw />\n" );
#endif

    x[0] = x1;
    x[1] = x2;
    y[0] = y1;
    y[1] = y2;

    plD_polyline_gcw( pls, x, y, (PLINT) 2 );
}


//--------------------------------------------------------------------------
// plD_eop_gcw()
//
// End of page.
//--------------------------------------------------------------------------

void plD_eop_gcw( PLStream *pls )
{
    GcwPLdev        * dev = pls->dev;
    GnomeCanvas     * canvas;

    GdkPixbuf       * pixbuf;
    GnomeCanvasItem * item;
    GnomeCanvasGroup* group;

    gdouble         dx, dy;

    gint            count = 1, n;

    void            *save_state;

    PLINT           width, height;

    if ( !GNOME_IS_CANVAS( dev->canvas ) )
        plexit( "GCW driver <plD_eop_gcw>: Canvas not found" );
    canvas = dev->canvas;

    // Ignore if there is no hidden group.  This means BOP has not been
    // called yet.
    //
    if ( !GNOME_IS_CANVAS_GROUP( dev->group_hidden ) )
        return;

#ifdef DEBUG_GCW_1
    gcw_debug( "<plD_eop_gcw>\n" );
#endif

    if ( dev->use_persistence )
        group = dev->group_persistent;
    else
        group = dev->group_hidden;

    // Retrieve the device width and height of the canvas
    width  = *(PLINT *) g_object_get_data( G_OBJECT( canvas ), "canvas-width" );
    height = *(PLINT *) g_object_get_data( G_OBJECT( canvas ), "canvas-height" );

    if ( dev->pixmap_has_data )
    {
        // Render the pixmap to a pixbuf on the canvas.
        if ( !GDK_IS_PIXBUF( pixbuf = gdk_pixbuf_get_from_drawable( NULL,
                     dev->background,
                     dev->colormap,
                     0, 0,
                     0, 0,
                     width, height ) ) )
        {
            plwarn( "GCW driver <plD_eop_gcw>: Can't draw pixmap into pixbuf." );
        }
        else // Pixbuf creation succeeded

        {
            if ( !GNOME_IS_CANVAS_ITEM(
                     item = gnome_canvas_item_new( dev->group_hidden,
                         GNOME_TYPE_CANVAS_PIXBUF,
                         "pixbuf", pixbuf,
                         "x", 1.,
                         "y", (gdouble) ( -height + 1. ),
                         "width", (gdouble) ( width ),
                         "height", (gdouble) ( height ),
                         NULL )
                     ) )
            {
                plwarn( "GCW driver <plD_eop_gcw>: Canvas item not created." );
            }

            // Free the pixbuf
            g_object_unref( pixbuf );
        }
    }
    else
    {
        // Use a rectangle for the background instead (faster)
        if ( !GNOME_IS_CANVAS_ITEM(
                 item = gnome_canvas_item_new(
                     dev->group_hidden,
                     GNOME_TYPE_CANVAS_RECT,
                     "x1", 0.,
                     "y1", (gdouble) ( -height ),
                     "x2", (gdouble) ( width ),
                     "y2", 0.,
                     "fill-color-rgba", plcolor_to_rgba( pls->cmap0[0], 0xFF ),
                     "width-units", 0.,
                     NULL )
                 ) )
        {
            plabort( "GCW driver <pld_eop_gcw>: Canvas item not created" );
            return;
        }
    }

    // Move the persistent group to the front
    gnome_canvas_item_raise_to_top( GNOME_CANVAS_ITEM( dev->group_persistent ) );

    // Move the background to the back
    if ( GNOME_IS_CANVAS_ITEM( item ) )
        gnome_canvas_item_lower_to_bottom( item );

    // Make the hidden group visible
    gnome_canvas_item_show( GNOME_CANVAS_ITEM( dev->group_hidden ) );

    // Destroy the old visible group
    if ( GNOME_IS_CANVAS_GROUP( dev->group_visible ) )
    {
        gtk_object_destroy( (GtkObject *) ( dev->group_visible ) );
        dev->group_visible = NULL;
    }

    // Clear the background pixmap
    if ( !dev->use_persistence && dev->pixmap_has_data )
        gcw_clear_background();

    // Name the hidden group as visible
    dev->group_visible = dev->group_hidden;
    dev->group_hidden  = NULL;

    // Update the canvas
    canvas->need_update = 1;
    gnome_canvas_update_now( canvas );

    //
    // Copy the plot buffer for future reference, otherwise it is
    // thrown out.
    //

    save_state = g_object_get_data( G_OBJECT( canvas ), "plotbuf" );
    save_state = (void *) plbuf_save( pls, save_state );

    // Attach the saved state to the canvas
    g_object_set_data( G_OBJECT( canvas ), "plotbuf", (gpointer) save_state );

    // If the driver is creating its own canvasses, set dev->canvas to be
    // NULL now in order to force creation of a new canvas when the next
    // drawing call is made.  The new canvas will be placed in a new
    // notebook page.
    //
    if ( dev->window != NULL )
    {
        dev->canvas           = NULL;
        dev->group_visible    = NULL;
        dev->group_hidden     = NULL;
        dev->group_persistent = NULL;
    }

#ifdef DEBUG_GCW_1
    gcw_debug( "</plD_eop_gcw>\n" );
#endif
}


//--------------------------------------------------------------------------
// plD_bop_gcw()
//
// Set up for the next page.
//
//--------------------------------------------------------------------------

void plD_bop_gcw( PLStream *pls )
{
    GcwPLdev   * dev = pls->dev;
    GnomeCanvas* canvas;

    if ( !GNOME_IS_CANVAS( dev->canvas ) )
    {
        if ( pls->hack )
            return;              // Wait for a canvas via DEVINIT
        else
            gcw_install_canvas( NULL );
    }
    canvas = dev->canvas;

#ifdef DEBUG_GCW_1
    gcw_debug( "<plD_bop_gcw>\n" );
#endif

    // Replay escape calls that come in before PLESC_DEVINIT.  Some of them
    // required a Canvas that didn't exist yet.
    //
    if ( dev->plstate_width )
        plD_state_gcw( pls, PLSTATE_WIDTH );
    if ( dev->plstate_color0 )
        plD_state_gcw( pls, PLSTATE_COLOR0 );
    if ( dev->plstate_color1 )
        plD_state_gcw( pls, PLSTATE_COLOR1 );
    dev->plstate_width  = FALSE;
    dev->plstate_color0 = FALSE;
    dev->plstate_color1 = FALSE;

    // Creat a new hidden group; all new drawing will be to this group
    if ( !GNOME_IS_CANVAS_ITEM(
             dev->group_hidden = GNOME_CANVAS_GROUP( gnome_canvas_item_new(
                     gnome_canvas_root( canvas ),
                     gnome_canvas_clipgroup_get_type(),
                     "x", 0.,
                     "y", 0.,
                     NULL ) )
             ) )
    {
        plexit( "GCW driver <plD_bop_gcw>: Canvas group cannot be created" );
    }

    // Set the clip to NULL
    g_object_set( G_OBJECT( dev->group_hidden ), "path", NULL, NULL );

    // Hide this group until drawing is done
    gnome_canvas_item_hide( GNOME_CANVAS_ITEM( dev->group_hidden ) );

#ifdef DEBUG_GCW_1
    gcw_debug( "</plD_bop_gcw>\n" );
#endif
}


//--------------------------------------------------------------------------
// plD_tidy_gcw()
//
// Close graphics file
//--------------------------------------------------------------------------

void plD_tidy_gcw( PLStream *pls )
{
    GcwPLdev* dev = pls->dev;

#ifdef DEBUG_GCW_1
    gcw_debug( "<plD_tidy_gcw>\n" );
#endif

#ifdef PL_HAVE_FREETYPE
    if ( pls->dev_text )
    {
        FT_Data *FT = (FT_Data *) pls->FT;
        plscmap0n( FT->ncol0_org );
        plD_FreeType_Destroy( pls );
    }
#endif

    if ( dev->window != NULL )
    {
        gtk_main();
    }

#ifdef DEBUG_GCW_1
    gcw_debug( "</plD_tidy_gcw>\n" );
#endif
}


//--------------------------------------------------------------------------
// plD_state_gcw()
//
// Handle change in PLStream state (color, pen width, fill attribute, etc).
//
// Note that PLplot sometimes tries to change states before the device is
// fully initialized (i.e., via PLESC_DEVINIT).  We must keep track of
// such attempts, and invoke the state change during the next call to
// plD_bop_gcw.
//
//--------------------------------------------------------------------------

void plD_state_gcw( PLStream *pls, PLINT op )
{
    GcwPLdev* dev = pls->dev;
    char    opname[20], msg[100];

#ifdef DEBUG_GCW_1
    if ( op == PLSTATE_WIDTH )
        strcpy( opname, "PLSTATE_WIDTH" );
    else if ( op == PLSTATE_COLOR0 )
        strcpy( opname, "PLSTATE_COLOR0" );
    else if ( op == PLSTATE_COLOR1 )
        strcpy( opname, "PLSTATE_COLOR1" );
    else if ( op == PLSTATE_FILL )
        strcpy( opname, "PLSTATE_FILL" );
    else if ( op == PLSTATE_CMAP0 )
        strcpy( opname, "PLSTATE_CMAP0" );
    else if ( op == PLSTATE_CMAP1 )
        strcpy( opname, "PLSTATE_CMAP1" );
    else
        strcpy( opname, "unknown" );
    snprintf( msg, 100, "<plD_state_gcw />: %s\n", opname );
    gcw_debug( msg );
#endif

    switch ( op )
    {
    case PLSTATE_WIDTH:
        if ( GNOME_IS_CANVAS( dev->canvas ) )
        {
            if ( dev->use_pixmap )
            {
                gdk_gc_set_line_attributes( dev->gc, pls->width,
                    GDK_LINE_SOLID,
                    GDK_CAP_BUTT,
                    GDK_JOIN_MITER );
            }
        }
        else
            dev->plstate_width = TRUE;
        break;

    case PLSTATE_COLOR0:
        if ( GNOME_IS_CANVAS( dev->canvas ) )
        {
            dev->color = plcolor_to_rgba( pls->cmap0[pls->icol0], 0xFF );
            if ( dev->use_pixmap )
                gcw_set_gdk_color();
        }
        else
            dev->plstate_color0 = TRUE;
        break;

    case PLSTATE_COLOR1:
        if ( GNOME_IS_CANVAS( dev->canvas ) )
        {
            dev->color = plcolor_to_rgba( pls->cmap1[pls->icol1], 0xFF );
            if ( dev->use_pixmap )
                gcw_set_gdk_color();
        }
        else
            dev->plstate_color1 = TRUE;
        break;

    case PLSTATE_FILL:
        break;

    case PLSTATE_CMAP0:
        break;

    case PLSTATE_CMAP1:
        break;

    default:
        break;
    }
}


//--------------------------------------------------------------------------
// fill_polygon()
//
// Fills the polygon defined by the given points.  Used for shade
// plotting.  Only solid fills are allowed.
//--------------------------------------------------------------------------

static void fill_polygon( PLStream* pls )
{
    GnomeCanvasPoints* points;
    GnomeCanvasGroup * group;
    GnomeCanvasItem  * item;
    GcwPLdev         * dev = pls->dev;
    GnomeCanvas      * canvas;

    PLINT            i;

    GdkPoint         * gdkpoints;

    PLINT            tmp;

#ifdef DEBUG_GCW_2
    gcw_debug( "<fill_polygon />\n" );
#endif

    if ( !GNOME_IS_CANVAS( dev->canvas ) )
        plexit( "GCW driver <fill_polygon>: Canvas not found" );
    canvas = dev->canvas;

    if ( dev->use_persistence )
        group = dev->group_persistent;
    else
        group = dev->group_hidden;

    if ( dev->use_pixmap && !dev->use_persistence ) // Write to a pixmap

    {
        if ( ( gdkpoints = (GdkPoint *) malloc( pls->dev_npts * sizeof ( GdkPoint ) ) ) == NULL )
        {
            plabort( "GCW driver <fill_polygon>: Could not create gdkpoints" );
            return;
        }

        if ( !pls->portrait )
        {
            for ( i = 0; i < pls->dev_npts; i++ )
            {
                gdkpoints[i].x = (gint) ( pls->dev_x[i] / VSCALE );
                gdkpoints[i].y = (gint) ( dev->height - pls->dev_y[i] / VSCALE );
            }
        }
        else // Swap x and y for portrait mode
        {
            for ( i = 0; i < pls->dev_npts; i++ )
            {
                gdkpoints[i].x = (gint) ( dev->height - pls->dev_y[i] / VSCALE );
                gdkpoints[i].y = (gint) ( dev->width - pls->dev_x[i] / VSCALE );
            }
        }

        gdk_draw_polygon( dev->background, dev->gc, TRUE, gdkpoints, pls->dev_npts );

        dev->pixmap_has_data = TRUE;

        free( gdkpoints );
    }
    else // Use Gnome Canvas polygons

    {
        if ( ( points = gnome_canvas_points_new( pls->dev_npts ) ) == NULL )
        {
            plabort( "GCW driver <fill_polygon>: Could not create points" );
            return;
        }

        if ( !pls->portrait )
        {
            for ( i = 0; i < pls->dev_npts; i++ )
            {
                points->coords[2 * i]     = (gdouble) ( pls->dev_x[i] / VSCALE );
                points->coords[2 * i + 1] = (gdouble) ( -pls->dev_y[i] / VSCALE );
            }
        }
        else // Swap x and y for portrait mode
        {
            for ( i = 0; i < pls->dev_npts; i++ )
            {
                points->coords[2 * i]     = (gdouble) ( dev->height - pls->dev_y[i] / VSCALE );
                points->coords[2 * i + 1] = (gdouble) ( -pls->dev_x[i] / VSCALE );
            }
        }

        if ( !GNOME_IS_CANVAS_ITEM(
                 item = gnome_canvas_item_new( group,
                     GNOME_TYPE_CANVAS_POLYGON,
                     "points", points,
                     "fill-color-rgba", dev->color,
                     // "outline-color-rgba",dev->color,
                     NULL )
                 ) )
        {
            plwarn( "GCW driver <fill_polygon>: Canvas item not created." );
        }

        gnome_canvas_points_free( points );


        // Draw a thin outline for each polygon; note that doing this
        // using the "outline-color-rgba" property above can result in
        // Canvas errors.
        //
        tmp        = pls->width;
        pls->width = 1;
        plD_polyline_gcw( pls, pls->dev_x, pls->dev_y, pls->dev_npts );
        pls->width = tmp;
    }
}

#ifdef PL_HAVE_FREETYPE
//--------------------------------------------------------------------------
// proc_str()
//
// Handles call to draw text on the canvas when the HAS_TEXT escape funtion
// case is invoked.
//
// This routine is unicode enabled, and requires freetype.
//--------------------------------------------------------------------------

static void proc_str( PLStream *pls, EscText *args )
{
    PLFLT           *t = args->xform; // Transform matrix for string

    GnomeCanvasGroup* group;
    GcwPLdev        * dev = pls->dev;
    GnomeCanvas     * canvas;

    PLUNICODE       fci; // The unicode font characterization integer
    guchar          *fontname = NULL;
    gint            font_size;
    GnomeFont       *font;
    GnomeFontFace   *face;
    GnomeGlyphList  *glyphlist;
    guint           Nglyphs;

    gdouble         affine_baseline[6]  = { 0., 0., 0., 0., 0., 0. }; // Affine transforms
    gdouble         affine_translate[6] = { 0., 0., 0., 0., 0., 0. };
    gdouble         affine_rotate[6]    = { 0., 0., 0., 0., 0., 0. };
    gdouble         affine_plplot[6]    = { 0., 0., 0., 0., 0., 0. };

    GnomeCanvasItem * item[200];             // List of string segments
    gdouble         width[200], height[200]; // Height and width of string segment
    gdouble         up_list[200];            // Indicates sub/sup position of string segment
    gdouble         up = 0, scale = 1;       // Used to create superscripts and subscripts

    ArtDRect        bbox;                    // Bounding box for each segment to get width & height

    const PLUNICODE *text;                   // The text and pointers to it
    guint           i = 0, Ntext;            // The text index and maximum length

    char            esc;                     // The escape character

    guint           N           = 0;         // The number of text segments
    gdouble         total_width = 0, sum_width = 0;

    guint           symbol;


#ifdef DEBUG_GCW_2
    gcw_debug( "<proc_str>\n" );
#endif

    if ( !GNOME_IS_CANVAS( dev->canvas ) )
        plexit( "GCW driver <proc_str>: Canvas not found" );
    canvas = dev->canvas;

    if ( dev->use_persistence )
        group = dev->group_persistent;
    else
        group = dev->group_hidden;

    // Retrieve the escape character
    plgesc( &esc );

    // Put the transform matrix values in the order expected by libart.
    // Note that the plplot transform matrix only has a rotation and shear;
    // plplot's rotation direction and shear are opposite from that expected
    // by libart, hence the negative signs below.
    //
    affine_plplot[0] = t[0];  // cos(theta)
    affine_plplot[1] = -t[2]; // sin(theta)
    affine_plplot[2] = -t[1]; // a cos(theta) - sin(theta)
    affine_plplot[3] = t[3];  // a sin(theta) + cos(theta)

    // Font size: size is in pixels but chrht is in mm.  Why the extra factor?
    font_size = (gint) ( pls->chrht * DEVICE_PIXELS_PER_MM * 1.5 );

    // Determine the default font
    plgfci( &fci );
    fontname = plP_FCI2FontName( fci, FontLookup, N_TrueTypeLookup );
    if ( fontname == NULL )
    {
        plabort( "GCW driver <proc_str>: FCI inconsistent with TrueTypeLookup" );
        return;
    }

    // Retrieve the font face
    face = gnome_font_face_find_from_filename( fontname, 0 );

    // Get the unicode string
    text  = args->unicode_array;
    Ntext = (guint) ( args->unicode_array_len );

    // Process the string: Break it into segments of constant font and size,
    // making sure we process control characters as we come to them.  Save
    // the extra information that will allow us to place the text on the
    // canvas.
    //
    while ( i < Ntext )
    {
        // Process the next character

        if ( text[i] & PL_FCI_MARK ) // Is it a font characterization index?

        {                            // Determine the font name
            fontname = plP_FCI2FontName( text[i], FontLookup, N_TrueTypeLookup );
            if ( fontname == NULL )
            {
                plabort( "GCW driver <proc_str>: FCI inconsistent with "
                    "TrueTypeLookup" );
                return;
            }

            // Retrieve the font face
            gnome_font_unref( face ); // We already have a face
            face = gnome_font_face_find_from_filename( fontname, 0 );

            i++; // Move ahead to the next character
        }
        else
        {
            if ( text[i] == esc ) // Check for escape sequences

            {                     // Process escape sequence
                i++;              // Move on to next character
                if ( i >= Ntext )
                {
                    plwarn( "GCW driver <proc_str>: Invalid escape sequence "
                        "provided in text." );
                    return;
                }

                switch ( text[i] )
                {
                case '#':  // <esc><esc>; this should translate to a hash
                    break; // Watch out for it later

                // Move to lower sub/sup position
                case 'd':
                case 'D':
                    if ( up > 0. )
                        scale *= 1.25;            // Subscript scaling parameter
                    else
                        scale *= 0.8;             // Subscript scaling parameter
                    up -= font_size / 2.;
                    break;

                // Move to higher sub/sup position
                case 'u':
                case 'U':
                    if ( up < 0. )
                        scale *= 1.25;            // Subscript scaling parameter
                    else
                        scale *= 0.8;             // Subscript scaling parameter
                    up += font_size / 2.;
                    break;

                // Ignore the next sequences

                // Overline
                case '+':

                // Underline
                case '-':

                // Backspace
                case 'b':
                case 'B':
                    plwarn( "GCW driver <proc_str>: '+', '-', and 'b' text "
                        "escape sequences not processed." );
                    break;
                } // switch(text[i])

                if ( text[i] != '#' )
                    i++; // Move ahead to the next character
            } // if(text[i] == esc)
        }                // if(text[i] & PL_FCI_MARK)


        if ( i == Ntext )
            continue;               // End of string

        // Save the sub/sup position
        up_list[N] = up;

        // Get the font
        font = gnome_font_face_get_font_default( face, font_size * scale );
        // printf("\n\nfont name = %s\n\n",gnome_font_get_name(font));

        // Create the glyphlist for this text segment
        glyphlist = gnome_glyphlist_new();
        gnome_glyphlist_font( glyphlist, font );
        gnome_glyphlist_color( glyphlist, dev->color );
        gnome_glyphlist_advance( glyphlist, TRUE );
        gnome_glyphlist_kerning( glyphlist, 0. );
        gnome_glyphlist_letterspace( glyphlist, 0. );

        // Free the font
        gnome_font_unref( font );

        // Move along to the next escape or FCI character, stuffing
        // everything else into the glyphlist.
        //
        Nglyphs = 0;
        while ( i < Ntext && !( text[i] & PL_FCI_MARK ) )
        {
            // Differentiate between ## and escape sequences
            if ( text[i] == esc )
            {
                if ( !( i > 0 && text[i - 1] == esc ) )
                    break;
            }

            gnome_glyphlist_glyph( glyphlist,
                gnome_font_lookup_default( font, text[i] ) );
            i++; Nglyphs++;
        }

        if ( Nglyphs )
        {
            // Determine the bounding box of the text
            gnome_glyphlist_bbox( glyphlist, NULL, 0, &bbox );
            width[N]  = bbox.x1 - bbox.x0;
            height[N] = bbox.y1 - bbox.y0;

            // Keep track of the total string width so that we can justify it
            total_width += width[N];
            if ( N != 0 )
                total_width += 2;           // Add a little extra space

            // Create the canvas text item
            if ( !GNOME_IS_CANVAS_ITEM(
                     item[N] = gnome_canvas_item_new( group,
                         PLPLOT_TYPE_CANVAS_HACKTEXT,
                         "glyphlist", glyphlist,
                         "fill-color-rgba", dev->color,
                         "x", 0.,
                         "y", 0.,
                         NULL )
                     ) )
            {
                plabort( "GCW driver <proc_str>: Canvas item not created" );
                return;
            }

            // Free the glyphlist
            gnome_glyphlist_unref( glyphlist );

            // Advance to next string segment
            N++;
        } // if(Nglyphs)


        // Don't overflow buffer
        if ( N == 200 && i < Ntext )
        {
            plabort( "GCW driver <proc_str>: too many text segments" );
            return;
        }
    } // while(i<Ntext)

    // We have all of the string segments.  Place each on the canvas
    // appropriately.
    //
    for ( i = 0; i < N; i++ )
    {
        // Calculate and apply the affine transforms
        art_affine_rotate( affine_rotate, 90. * ( pls->diorot - pls->portrait ) );
        if ( !pls->portrait )
        {
            art_affine_translate( affine_baseline,
                -total_width * args->just + sum_width,
                height[0] / 2.5 - up_list[i] );
            art_affine_translate( affine_translate,
                args->x / VSCALE, -args->y / VSCALE );
        }
        else // Swap x and y for portrait mode
        {
            art_affine_translate( affine_baseline,
                -total_width * args->just + sum_width,
                height[0] / 2.5 - up_list[i] );
            art_affine_translate( affine_translate,
                dev->height - args->y / VSCALE, -args->x / VSCALE );
        }
        gnome_canvas_item_affine_relative( item[i], affine_translate );
        gnome_canvas_item_affine_relative( item[i], affine_rotate );
        gnome_canvas_item_affine_relative( item[i], affine_plplot );
        gnome_canvas_item_affine_relative( item[i], affine_baseline );

        // Keep track of the position in the string
        sum_width += width[i];
        if ( i != N - 1 )
            sum_width += 2;               // Add a little extra space
    }

#ifdef DEBUG_GCW_2
    gcw_debug( "</proc_str>\n" );
#endif
}
#endif //PL_HAVE_FREETYPE


//--------------------------------------------------------------------------
// plD_esc_gcw()
//
// Escape functions.
//
//--------------------------------------------------------------------------

void plD_esc_gcw( PLStream *pls, PLINT op, void *ptr )
{
    GcwPLdev* dev = pls->dev;

#ifdef DEBUG_GCW_1
    char opname[20], msg[100];
    if ( op == PLESC_DEVINIT )
        strcpy( opname, "PLESC_DEVINIT" );
    else if ( op == PLESC_CLEAR )
        strcpy( opname, "PLESC_CLEAR" );
    else if ( op == PLESC_FILL )
        strcpy( opname, "PLESC_FILL" );
    else if ( op == PLESC_HAS_TEXT )
        strcpy( opname, "PLESC_HAS_TEXT" );
    else if ( op == PLESC_GRAPH )
        strcpy( opname, "PLESC_GRAPH" );
    else
        strcpy( opname, "unknown" );
    snprintf( msg, 100, "<plD_esc_gcw />: %s\n", opname );
    gcw_debug( msg );
#endif

    switch ( op )
    {
    case PLESC_DEVINIT:
        gcw_init_canvas( GNOME_CANVAS( ptr ) );
        pls->hack = 0;
        break;

    case PLESC_CLEAR:
        break;

    case PLESC_FILL:
        fill_polygon( pls );
        break;

#ifdef PL_HAVE_FREETYPE
    case PLESC_HAS_TEXT:
        proc_str( pls, ptr ); // Draw the text
        break;
#endif

    case PLESC_GRAPH:
        break;

    default:
        break;
    }
}