path: root/libgnomecanvas/gnome-canvas-rect.c

/* Generic bezier rect item for GnomeCanvasWidget.  Most code taken
 * from gnome-canvas-bpath but made into a rect item.
 *
 * GnomeCanvas is basically a port of the Tk toolkit's most excellent
 * canvas widget.  Tk is copyrighted by the Regents of the University
 * of California, Sun Microsystems, and other parties.
 *
 * Copyright (C) 1998,1999 The Free Software Foundation
 *
 * Authors: Federico Mena <federico@nuclecu.unam.mx>
 *          Raph Levien <raph@acm.org>
 *          Lauris Kaplinski <lauris@ximian.com>
 *          Miguel de Icaza <miguel@kernel.org>
 *          Cody Russell <bratsche@gnome.org>
 *          Rusty Conover <rconover@bangtail.net>
 */

/* These includes are set up for standalone compile. If/when this codebase
 * is integrated into libgnomeui, the includes will need to change. */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <math.h>
#include <string.h>

#include <gtk/gtk.h>
#include <cairo-gobject.h>
#include "gnome-canvas.h"
#include "gnome-canvas-util.h"

#include "gnome-canvas-rect.h"

#define GNOME_CANVAS_RECT_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), GNOME_TYPE_CANVAS_RECT, GnomeCanvasRectPrivate))

struct _GnomeCanvasRectPrivate {
    cairo_path_t *path;             /* Our bezier path representation */

    gdouble x1, y1, x2, y2;

    gdouble scale;          /* CTM scaling (for pen) */

    guint fill_set : 1;     /* Is fill color set? */
    guint outline_set : 1;      /* Is outline color set? */

    gdouble line_width;     /* Width of outline, in user coords */

    guint32 fill_rgba;      /* Fill color, RGBA */
    guint32 outline_rgba;       /* Outline color, RGBA */

    cairo_line_cap_t cap;       /* Cap style for line */
    cairo_line_join_t join;     /* Join style for line */
    cairo_fill_rule_t wind;     /* Winding rule */
    gdouble miterlimit;     /* Miter limit */

        guint n_dash;                   /* Number of elements in dashing pattern */
    gdouble *dash;      /* Dashing pattern */
        gdouble dash_offset;            /* Dashing offset */
};

enum {
    PROP_0,
    PROP_X1,
    PROP_Y1,
    PROP_X2,
    PROP_Y2,
    PROP_FILL_COLOR,
    PROP_FILL_COLOR_GDK,
    PROP_FILL_COLOR_RGBA,
    PROP_OUTLINE_COLOR,
    PROP_OUTLINE_COLOR_GDK,
    PROP_OUTLINE_COLOR_RGBA,
    PROP_LINE_WIDTH,
    PROP_CAP_STYLE,
    PROP_JOIN_STYLE,
    PROP_WIND,
    PROP_MITERLIMIT,
    PROP_DASH
};

static void   gnome_canvas_rect_bounds      (GnomeCanvasItem *item,
                          gdouble *x1, gdouble *y1, gdouble *x2, gdouble *y2);

G_DEFINE_TYPE (GnomeCanvasRect, gnome_canvas_rect, GNOME_TYPE_CANVAS_ITEM)

static guint32
get_rgba_from_color (GdkColor *color)
{
    return ((color->red & 0xff00) << 16) |
        ((color->green & 0xff00) << 8) |
        (color->blue & 0xff00) | 0xff;
}

static gboolean
gnome_canvas_rect_setup_for_fill (GnomeCanvasRect *rect,
                                  cairo_t *cr)
{
    if (!rect->priv->fill_set)
        return FALSE;

    cairo_set_source_rgba (
        cr,
        ((rect->priv->fill_rgba >> 24) & 0xff) / 255.0,
        ((rect->priv->fill_rgba >> 16) & 0xff) / 255.0,
        ((rect->priv->fill_rgba >>  8) & 0xff) / 255.0,
        ( rect->priv->fill_rgba        & 0xff) / 255.0);
    cairo_set_fill_rule (cr, rect->priv->wind);

    return TRUE;
}

static gboolean
gnome_canvas_rect_setup_for_stroke (GnomeCanvasRect *rect,
                                    cairo_t *cr)
{
    if (!rect->priv->outline_set)
        return FALSE;

    cairo_set_source_rgba (
        cr,
        ((rect->priv->outline_rgba >> 24) & 0xff) / 255.0,
        ((rect->priv->outline_rgba >> 16) & 0xff) / 255.0,
        ((rect->priv->outline_rgba >>  8) & 0xff) / 255.0,
        ( rect->priv->outline_rgba        & 0xff) / 255.0);
    cairo_set_line_width (cr, rect->priv->line_width);
    cairo_set_line_cap (cr, rect->priv->cap);
    cairo_set_line_join (cr, rect->priv->join);
    cairo_set_miter_limit (cr, rect->priv->miterlimit);
    cairo_set_dash (
        cr, rect->priv->dash, rect->priv->n_dash,
        rect->priv->dash_offset);

    return TRUE;
}

static void
gnome_canvas_rect_set_property (GObject *object,
                                guint property_id,
                                const GValue *value,
                                GParamSpec *pspec)
{
    GnomeCanvasItem *item;
    GnomeCanvasRect *rect;
    GnomeCanvasRectPrivate *priv;
    GdkColor color;
    GdkColor *colorptr;
    const gchar *color_string;

    item = GNOME_CANVAS_ITEM (object);
    rect = GNOME_CANVAS_RECT (object);
    priv = rect->priv;

    switch (property_id) {
    case PROP_X1:
        priv->x1 = g_value_get_double (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_Y1:
        priv->y1 = g_value_get_double (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_X2:
        priv->x2 = g_value_get_double (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_Y2:
        priv->y2 = g_value_get_double (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_FILL_COLOR:
        color_string = g_value_get_string (value);
        if (color_string != NULL) {
            if (!gdk_color_parse (color_string, &color)) {
                g_warning (
                    "Failed to parse color '%s'",
                    color_string);
                break;
            }
            priv->fill_set = TRUE;
            priv->fill_rgba = get_rgba_from_color (&color);
        } else if (priv->fill_set)
            priv->fill_set = FALSE;
        else
            break;

        gnome_canvas_item_request_update (item);
        break;

    case PROP_FILL_COLOR_GDK:
        colorptr = g_value_get_boxed (value);
        if (colorptr != NULL) {
            priv->fill_set = TRUE;
            priv->fill_rgba = get_rgba_from_color (colorptr);
        } else if (priv->fill_set)
            priv->fill_set = FALSE;
        else
            break;

        gnome_canvas_item_request_update (item);
        break;

    case PROP_FILL_COLOR_RGBA:
        priv->fill_set = TRUE;
        priv->fill_rgba = g_value_get_uint (value);

        gnome_canvas_item_request_update (item);
        break;

    case PROP_OUTLINE_COLOR:
        color_string = g_value_get_string (value);
        if (color_string != NULL) {
            if (!gdk_color_parse (color_string, &color)) {
                g_warning (
                    "Failed to parse color '%s'",
                    color_string);
                break;
            }
            priv->outline_set = TRUE;
            priv->outline_rgba = get_rgba_from_color (&color);
        } else if (priv->outline_set)
            priv->outline_set = FALSE;
        else
            break;

        gnome_canvas_item_request_update (item);
        break;

    case PROP_OUTLINE_COLOR_GDK:
        colorptr = g_value_get_boxed (value);
        if (colorptr != NULL) {
            priv->outline_set = TRUE;
            priv->outline_rgba = get_rgba_from_color (colorptr);
        } else if (priv->outline_set)
            priv->outline_set = FALSE;
        else
            break;

        gnome_canvas_item_request_update (item);
        break;

    case PROP_OUTLINE_COLOR_RGBA:
        priv->outline_set = TRUE;
        priv->outline_rgba = g_value_get_uint (value);

        gnome_canvas_item_request_update (item);
        break;

    case PROP_LINE_WIDTH:
        priv->line_width = g_value_get_double (value);

        gnome_canvas_item_request_update (item);
        break;

    case PROP_WIND:
        priv->wind = g_value_get_enum (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_CAP_STYLE:
        priv->cap = g_value_get_enum (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_JOIN_STYLE:
        priv->join = g_value_get_enum (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_MITERLIMIT:
        priv->miterlimit = g_value_get_double (value);
        gnome_canvas_item_request_update (item);
        break;

    case PROP_DASH:
        /* XXX */
        g_warn_if_reached ();
        break;

    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
        break;
    }
}

static void
gnome_canvas_rect_get_property (GObject *object,
                                guint property_id,
                                GValue *value,
                                GParamSpec *pspec)
{
    GnomeCanvasRect *rect = GNOME_CANVAS_RECT (object);
    GnomeCanvasRectPrivate *priv = rect->priv;

    switch (property_id) {

    case PROP_X1:
        g_value_set_double (value, priv->x1);
        break;

    case PROP_Y1:
        g_value_set_double (value, priv->y1);
        break;

    case PROP_X2:
        g_value_set_double (value, priv->x2);
        break;

    case PROP_Y2:
        g_value_set_double (value, priv->y2);
        break;

    case PROP_FILL_COLOR_RGBA:
        g_value_set_uint (value, priv->fill_rgba);
        break;

    case PROP_OUTLINE_COLOR_RGBA:
        g_value_set_uint (value, priv->outline_rgba);
        break;

    case PROP_WIND:
        g_value_set_uint (value, priv->wind);
        break;

    case PROP_CAP_STYLE:
        g_value_set_enum (value, priv->cap);
        break;

    case PROP_JOIN_STYLE:
        g_value_set_enum (value, priv->join);
        break;

    case PROP_LINE_WIDTH:
        g_value_set_double (value, priv->line_width);
        break;

    case PROP_MITERLIMIT:
        g_value_set_double (value, priv->miterlimit);
        break;

    case PROP_DASH:
        /* XXX */
        g_warn_if_reached ();
        break;

    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
        break;
    }
}

static void
gnome_canvas_rect_dispose (GnomeCanvasItem *object)
{
    GnomeCanvasRect *rect;

    g_return_if_fail (GNOME_IS_CANVAS_RECT (object));

    rect = GNOME_CANVAS_RECT (object);

    if (rect->priv->path != NULL) {
        cairo_path_destroy (rect->priv->path);
        rect->priv->path = NULL;
    }

    g_free (rect->priv->dash);
    rect->priv->dash = NULL;

    if (GNOME_CANVAS_ITEM_CLASS (gnome_canvas_rect_parent_class)->dispose)
        GNOME_CANVAS_ITEM_CLASS (gnome_canvas_rect_parent_class)->dispose (object);
}

static void
gnome_canvas_rect_update (GnomeCanvasItem *item,
                          const cairo_matrix_t *i2c,
                          gint flags)
{
    gdouble x1, x2, y1, y2;

    GNOME_CANVAS_ITEM_CLASS (gnome_canvas_rect_parent_class)->
        update (item, i2c, flags);

    gnome_canvas_rect_bounds (item, &x1, &y1, &x2, &y2);
    gnome_canvas_matrix_transform_rect (i2c, &x1, &y1, &x2, &y2);

    gnome_canvas_update_bbox (
        item, floor (x1), floor (y1), ceil (x2), ceil (y2));
}

static void
gnome_canvas_rect_draw (GnomeCanvasItem *item,
                        cairo_t *cr,
                        gint x,
                        gint y,
                        gint width,
                        gint height)
{
    GnomeCanvasRect *rect;
    cairo_matrix_t matrix;

    rect = GNOME_CANVAS_RECT (item);

    cairo_save (cr);

    gnome_canvas_item_i2c_matrix (item, &matrix);
    cairo_transform (cr, &matrix);

    if (gnome_canvas_rect_setup_for_fill (rect, cr)) {
        cairo_rectangle (
            cr,
            rect->priv->x1 - x,
            rect->priv->y1 - y,
            rect->priv->x2 - rect->priv->x1,
            rect->priv->y2 - rect->priv->y1);
        cairo_fill (cr);
    }

    if (gnome_canvas_rect_setup_for_stroke (rect, cr)) {
        cairo_rectangle (
            cr,
            rect->priv->x1 - x,
            rect->priv->y1 - y,
            rect->priv->x2 - rect->priv->x1,
            rect->priv->y2 - rect->priv->y1);
        cairo_stroke (cr);
    }

    cairo_restore (cr);
}

static GnomeCanvasItem *
gnome_canvas_rect_point (GnomeCanvasItem *item,
                         gdouble x,
                         gdouble y,
                         gint cx,
                         gint cy)
{
    GnomeCanvasRect *rect;
    cairo_t *cr;

    rect = GNOME_CANVAS_RECT (item);

    cr = gnome_canvas_cairo_create_scratch ();

    cairo_rectangle (
        cr,
        rect->priv->x1,
        rect->priv->y1,
        rect->priv->x2 - rect->priv->x1,
        rect->priv->y2 - rect->priv->y1);

    if (gnome_canvas_rect_setup_for_fill (rect, cr) &&
        cairo_in_fill (cr, x, y)) {
        cairo_destroy (cr);
        return item;
    }

    if (gnome_canvas_rect_setup_for_stroke (rect, cr) &&
        cairo_in_stroke (cr, x, y)) {
        cairo_destroy (cr);
        return item;
    }

    cairo_destroy (cr);

    return NULL;
}

static void
gnome_canvas_rect_bounds (GnomeCanvasItem *item,
                          gdouble *x1,
                          gdouble *y1,
                          gdouble *x2,
                          gdouble *y2)
{
    GnomeCanvasRect *rect;
    cairo_t *cr;

    rect = GNOME_CANVAS_RECT (item);

    cr = gnome_canvas_cairo_create_scratch ();

    cairo_rectangle (
        cr,
        rect->priv->x1,
        rect->priv->y1,
        rect->priv->x2 - rect->priv->x1,
        rect->priv->y2 - rect->priv->y1);

    if (gnome_canvas_rect_setup_for_stroke (rect, cr))
        cairo_stroke_extents (cr, x1, y1, x2, y2);
    else if (gnome_canvas_rect_setup_for_fill (rect, cr))
        cairo_fill_extents (cr, x1, y1, x2, y2);
    else {
        *x1 = *x2 = *y1 = *y2 = 0;
    }

    cairo_destroy (cr);
}

static void
gnome_canvas_rect_class_init (GnomeCanvasRectClass *class)
{
    GObjectClass *object_class;
    GnomeCanvasItemClass *item_class;

    g_type_class_add_private (class, sizeof (GnomeCanvasRectPrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = gnome_canvas_rect_set_property;
    object_class->get_property = gnome_canvas_rect_get_property;

    item_class = GNOME_CANVAS_ITEM_CLASS (class);
    item_class->dispose = gnome_canvas_rect_dispose;
    item_class->update = gnome_canvas_rect_update;
    item_class->draw = gnome_canvas_rect_draw;
    item_class->point = gnome_canvas_rect_point;
    item_class->bounds = gnome_canvas_rect_bounds;

    g_object_class_install_property (
        object_class,
        PROP_X1,
        g_param_spec_double (
            "x1",
            NULL,
            NULL,
            -G_MAXDOUBLE,
            G_MAXDOUBLE,
            0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_Y1,
        g_param_spec_double (
            "y1",
            NULL,
            NULL,
            -G_MAXDOUBLE,
            G_MAXDOUBLE,
            0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_X2,
        g_param_spec_double (
            "x2",
            NULL,
            NULL,
            -G_MAXDOUBLE,
            G_MAXDOUBLE,
            0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_Y2,
        g_param_spec_double (
            "y2",
            NULL,
            NULL,
            -G_MAXDOUBLE,
            G_MAXDOUBLE,
            0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_FILL_COLOR,
        g_param_spec_string (
            "fill_color",
            NULL,
            NULL,
            NULL,
            G_PARAM_WRITABLE));

    g_object_class_install_property (
        object_class,
        PROP_FILL_COLOR_GDK,
        g_param_spec_boxed (
            "fill_color_gdk",
            NULL,
            NULL,
            GDK_TYPE_COLOR,
            G_PARAM_WRITABLE));

    g_object_class_install_property (
        object_class,
        PROP_FILL_COLOR_RGBA,
        g_param_spec_uint (
            "fill_color_rgba",
            NULL,
            NULL,
            0,
            G_MAXUINT,
            0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_OUTLINE_COLOR,
        g_param_spec_string (
            "outline_color",
            NULL,
            NULL,
            NULL,
            G_PARAM_WRITABLE));

    g_object_class_install_property (
        object_class,
        PROP_OUTLINE_COLOR_GDK,
        g_param_spec_boxed (
            "outline_color_gdk",
            NULL,
            NULL,
            GDK_TYPE_COLOR,
            G_PARAM_WRITABLE));

    g_object_class_install_property (
        object_class,
        PROP_OUTLINE_COLOR_RGBA,
        g_param_spec_uint (
            "outline_rgba",
            NULL,
            NULL,
            0,
            G_MAXUINT,
            0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_LINE_WIDTH,
        g_param_spec_double (
            "line_width",
            NULL,
            NULL,
            0.0,
            G_MAXDOUBLE,
            1.0,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_CAP_STYLE,
        g_param_spec_enum (
            "cap_style",
            NULL,
            NULL,
            CAIRO_GOBJECT_TYPE_LINE_CAP,
            CAIRO_LINE_CAP_BUTT,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_JOIN_STYLE,
        g_param_spec_enum (
            "join_style",
            NULL,
            NULL,
            CAIRO_GOBJECT_TYPE_LINE_JOIN,
            CAIRO_LINE_JOIN_MITER,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_WIND,
        g_param_spec_enum (
            "wind",
            NULL,
            NULL,
            CAIRO_GOBJECT_TYPE_FILL_RULE,
            CAIRO_FILL_RULE_EVEN_ODD,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_MITERLIMIT,
        g_param_spec_double (
            "miterlimit",
            NULL,
            NULL,
            0.0,
            G_MAXDOUBLE,
            10.43,
            G_PARAM_READWRITE));

#if 0
    /* XXX: Find a good way to pass dash properties in a property */
    g_object_class_install_property (
        object_class,
        PROP_DASH,
        g_param_spec_pointer (
            "dash",
            NULL,
            NULL,
            G_PARAM_READWRITE));
#endif
}

static void
gnome_canvas_rect_init (GnomeCanvasRect *rect)
{
    rect->priv = GNOME_CANVAS_RECT_GET_PRIVATE (rect);

    rect->priv->scale = 1.0;

    rect->priv->fill_set = FALSE;
    rect->priv->outline_set = FALSE;

    rect->priv->line_width = 1.0;

    rect->priv->fill_rgba = 0x0000003f;
    rect->priv->outline_rgba = 0x0000007f;

    rect->priv->cap = CAIRO_LINE_CAP_BUTT;
    rect->priv->join = CAIRO_LINE_JOIN_MITER;
    rect->priv->wind = CAIRO_FILL_RULE_EVEN_ODD;
    rect->priv->miterlimit = 10.43;    /* X11 default */

    rect->priv->n_dash = 0;
    rect->priv->dash = NULL;
}