/*!
\brief Initializes the gauge attributes to sane defaults
\param gauge (MtxPieGauge *) pointer to the gauge object
*/
void mtx_pie_gauge_init (MtxPieGauge *gauge)
{
/* The events the gauge receives
* Need events for button press/release AND motion EVEN THOUGH
* we don't have a motion handler defined. It's required for the
* dash designer to do drag and move placement
*/
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
gtk_widget_add_events (GTK_WIDGET (gauge),GDK_BUTTON_PRESS_MASK
| GDK_BUTTON_RELEASE_MASK |GDK_POINTER_MOTION_MASK);
priv->w = 130;
priv->h = 20;
priv->pie_xc = 17; /* pie x center coord from LL corner */
priv->pie_yc = priv->h-3; /* pie y center coord from LL corner */
priv->pie_radius = 14; /* pie is 180deg swep so 14x28 pixels */
priv->value = 0.0; /* default values */
priv->min = 0.0;
priv->max = 100.0;
priv->precision = 2;
priv->start_angle = 180; /* lower left quadrant */
priv->sweep_angle = 180; /* CW sweep */
priv->value_font = g_strdup("Bitstream Vera Sans");
priv->value_font_scale = 0.2;
priv->cr = NULL;
priv->colormap = gdk_colormap_get_system();
priv->gc = NULL;
mtx_pie_gauge_init_colors(gauge);
/*mtx_pie_gauge_redraw (gauge);*/
}
/*!
\brief Allocates the default colors for a gauge with no options
\param widget (MegaPieGauge *) pointer to the gauge object
*/
void mtx_pie_gauge_init_colors(MtxPieGauge *gauge)
{
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
/*! Main Background */
priv->colors[COL_BG].red=0.914*65535;
priv->colors[COL_BG].green=0.914*65535;
priv->colors[COL_BG].blue=0.859*65535;
/*! Needle */
priv->colors[COL_NEEDLE].red=0.0*65535;
priv->colors[COL_NEEDLE].green=0.0*65535;
priv->colors[COL_NEEDLE].blue=0.0*65535;
/*! Text Color*/
priv->colors[COL_VALUE_FONT].red=0.1*65535;
priv->colors[COL_VALUE_FONT].green=0.1*65535;
priv->colors[COL_VALUE_FONT].blue=0.1*65535;
/*! Gauge BG Color Begin */
priv->colors[COL_LOW].red=0.0*65535;
priv->colors[COL_LOW].green=1.0*65535;
priv->colors[COL_LOW].blue=0.0*65535;
/*! Gauge BG Color Middle */
priv->colors[COL_MID].red=1.0*65535;
priv->colors[COL_MID].green=1.0*65535;
priv->colors[COL_MID].blue=0.0*65535;
/*! Gauge BG Color End */
priv->colors[COL_HIGH].red=1.0*65535;
priv->colors[COL_HIGH].green=0.0*65535;
priv->colors[COL_HIGH].blue=0.0*65535;
}
/*!
\brief sets the current value
\param gauge is the pointer to the gauge object
\param value is the new value
*/
void mtx_pie_gauge_set_value (MtxPieGauge *gauge, gfloat value)
{
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
g_return_if_fail (MTX_IS_PIE_GAUGE (gauge));
g_object_freeze_notify (G_OBJECT (gauge));
priv->value = value;
g_object_thaw_notify (G_OBJECT (gauge));
mtx_pie_gauge_redraw(gauge);
}
/*!
\brief handles exposure events when the screen is covered and then
exposed. Works by copying from a backing pixmap to screen,
\param widget (GtkWidget *) pointer to the gauge object
\param event (GdkEventExpose *) pointer to GDK event datastructure that
encodes important info like window dimensions and depth.
*/
gboolean mtx_pie_gauge_expose (GtkWidget *widget, GdkEventExpose *event)
{
MtxPieGauge * gauge = MTX_PIE_GAUGE(widget);
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
gdk_draw_drawable(widget->window,
widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
priv->pixmap,
event->area.x, event->area.y,
event->area.x, event->area.y,
event->area.width, event->area.height);
return FALSE;
}
/*!
\brief handles configure events whe nthe gauge gets created or resized.
Takes care of creating/destroying graphics contexts, backing pixmaps (two
levels are used to split the rendering for speed reasons) colormaps are
also created here as well
\param widget (GtkWidget *) pointer to the gauge object
\param event (GdkEventConfigure *) pointer to GDK event datastructure that
encodes important info like window dimensions and depth.
*/
gboolean mtx_pie_gauge_configure (GtkWidget *widget, GdkEventConfigure *event)
{
MtxPieGauge * gauge = MTX_PIE_GAUGE(widget);
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
priv->w = widget->allocation.width;
priv->h = widget->allocation.height;
if (priv->gc)
g_object_unref(priv->gc);
/* Backing pixmap (copy of window) */
if (priv->pixmap)
g_object_unref(priv->pixmap);
priv->pixmap=gdk_pixmap_new(widget->window,
priv->w,priv->h,
gtk_widget_get_visual(widget)->depth);
gdk_draw_rectangle(priv->pixmap,
widget->style->black_gc,
TRUE, 0,0,
priv->w,priv->h);
/* Static Background pixmap */
if (priv->bg_pixmap)
g_object_unref(priv->bg_pixmap);
priv->bg_pixmap=gdk_pixmap_new(widget->window,
priv->w,priv->h,
gtk_widget_get_visual(widget)->depth);
gdk_draw_rectangle(priv->bg_pixmap,
widget->style->black_gc,
TRUE, 0,0,
priv->w,priv->h);
gdk_window_set_back_pixmap(widget->window,priv->pixmap,0);
priv->gc = gdk_gc_new(priv->bg_pixmap);
gdk_gc_set_colormap(priv->gc,priv->colormap);
if (priv->font_options)
cairo_font_options_destroy(priv->font_options);
priv->font_options = cairo_font_options_create();
cairo_font_options_set_antialias(priv->font_options,
CAIRO_ANTIALIAS_GRAY);
generate_pie_gauge_background(gauge);
update_pie_gauge_position(gauge);
return TRUE;
}
/*!
\brief gets the current value
\param gauge is the pointer to the gauge object
*/
gfloat mtx_pie_gauge_get_value (MtxPieGauge *gauge)
{
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
g_return_val_if_fail ((MTX_IS_PIE_GAUGE (gauge)),0.0);
return priv->value;
}
/*!
\brief draws the static elements of the gauge (only on resize), This includes
the border, units and name strings, tick marks and warning regions
This is the cairo version.
\param widget (MtxPieGauge *) pointer to the gauge object
*/
void generate_pie_gauge_background(MtxPieGauge *gauge)
{
cairo_t *cr = NULL;
gint w = 0;
gint h = 0;
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
w = GTK_WIDGET(gauge)->allocation.width;
h = GTK_WIDGET(gauge)->allocation.height;
if (!priv->bg_pixmap)
return;
/* get a cairo_t */
cr = gdk_cairo_create (priv->bg_pixmap);
cairo_set_font_options(cr,priv->font_options);
cairo_set_source_rgb (cr,
priv->colors[COL_BG].red/65535.0,
priv->colors[COL_BG].green/65535.0,
priv->colors[COL_BG].blue/65535.0);
/* Background Rectangle */
cairo_rectangle (cr,
0,0,w,h);
cairo_fill(cr);
/* first one big yellow, with the green and red on top
* This prevents seeing BG pixels due to antialiasing errors */
cairo_move_to(cr,priv->pie_xc,priv->pie_yc);
cairo_set_source_rgb (cr,
priv->colors[COL_MID].red/65535.0,
priv->colors[COL_MID].green/65535.0,
priv->colors[COL_MID].blue/65535.0);
cairo_arc(cr, priv->pie_xc, priv->pie_yc, priv->pie_radius,
priv->start_angle*(M_PI/180.0),
(priv->start_angle+priv->sweep_angle)*(M_PI/180.0));
cairo_fill(cr);
/* Low green Arc (*/
cairo_move_to(cr,priv->pie_xc,priv->pie_yc);
cairo_set_source_rgb (cr,
priv->colors[COL_LOW].red/65535.0,
priv->colors[COL_LOW].green/65535.0,
priv->colors[COL_LOW].blue/65535.0);
cairo_arc(cr, priv->pie_xc, priv->pie_yc, priv->pie_radius,
priv->start_angle*(M_PI/180.0),
(priv->start_angle+45)*(M_PI/180.0));
cairo_fill(cr);
/* High red Arc */
cairo_move_to(cr,priv->pie_xc,priv->pie_yc);
cairo_set_source_rgb (cr,
priv->colors[COL_HIGH].red/65535.0,
priv->colors[COL_HIGH].green/65535.0,
priv->colors[COL_HIGH].blue/65535.0);
cairo_arc(cr, priv->pie_xc, priv->pie_yc, priv->pie_radius,
(priv->start_angle+135)*(M_PI/180.0),
(priv->start_angle+180)*(M_PI/180.0));
cairo_fill(cr);
/* Pie Gauge Arcs */
cairo_set_line_width (cr, 1.0);
cairo_set_source_rgb (cr,
priv->colors[COL_NEEDLE].red/65535.0,
priv->colors[COL_NEEDLE].green/65535.0,
priv->colors[COL_NEEDLE].blue/65535.0);
cairo_arc(cr, priv->pie_xc, priv->pie_yc, priv->pie_radius,
priv->start_angle*(M_PI/180.0),
(priv->start_angle+priv->sweep_angle)*(M_PI/180.0));
cairo_stroke(cr);
cairo_destroy (cr);
}
/*!
\brief updates the gauge position, This is the CAIRO implementation that
looks a bit nicer, though is a little bit slower
\param widget (MtxPieGauge *) pointer to the gauge object
*/
void update_pie_gauge_position (MtxPieGauge *gauge)
{
GtkWidget * widget = NULL;
cairo_font_weight_t weight;
cairo_font_slant_t slant;
gfloat tmpf = 0.0;
gfloat needle_pos = 0.0;
gchar * tmpbuf = NULL;
gchar * message = NULL;
GdkPoint tip;
cairo_t *cr = NULL;
cairo_text_extents_t extents;
MtxPieGaugePrivate *priv = MTX_PIE_GAUGE_GET_PRIVATE(gauge);
widget = GTK_WIDGET(gauge);
/* Copy background pixmap to intermediary for final rendering */
gdk_draw_drawable(priv->pixmap,
widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
priv->bg_pixmap,
0,0,
0,0,
widget->allocation.width,widget->allocation.height);
cr = gdk_cairo_create (priv->pixmap);
cairo_set_font_options(cr,priv->font_options);
cairo_set_antialias(cr,CAIRO_ANTIALIAS_DEFAULT);
/* Update the VALUE text */
cairo_set_source_rgb (cr,
priv->colors[COL_VALUE_FONT].red/65535.0,
priv->colors[COL_VALUE_FONT].green/65535.0,
priv->colors[COL_VALUE_FONT].blue/65535.0);
tmpbuf = g_utf8_strup(priv->value_font,-1);
if (g_strrstr(tmpbuf,"BOLD"))
weight = CAIRO_FONT_WEIGHT_BOLD;
else
weight = CAIRO_FONT_WEIGHT_NORMAL;
if (g_strrstr(tmpbuf,"OBLIQUE"))
slant = CAIRO_FONT_SLANT_OBLIQUE;
else if (g_strrstr(tmpbuf,"ITALIC"))
slant = CAIRO_FONT_SLANT_ITALIC;
else
slant = CAIRO_FONT_SLANT_NORMAL;
g_free(tmpbuf);
cairo_select_font_face (cr, priv->value_font, slant, weight);
cairo_set_font_size (cr, 11);
if (priv->valname)
message = g_strdup_printf("%s:%.*f", priv->valname,priv->precision,priv->value);
else
message = g_strdup_printf("%.*f", priv->precision,priv->value);
cairo_text_extents (cr, message, &extents);
cairo_move_to (cr,
((priv->w-(priv->pie_radius*2.0 + 5)-extents.width)/2.0) +priv->pie_radius*2.0,
priv->pie_yc - (extents.height/4.0));
cairo_show_text (cr, message);
g_free(message);
cairo_stroke (cr);
/* gauge hands */
tmpf = (priv->value-priv->min)/(priv->max-priv->min);
needle_pos = (priv->start_angle+(tmpf*priv->sweep_angle))*(M_PI/180);
cairo_set_source_rgb (cr, priv->colors[COL_NEEDLE].red/65535.0,
priv->colors[COL_NEEDLE].green/65535.0,
priv->colors[COL_NEEDLE].blue/65535.0);
cairo_set_line_width (cr, 1.5);
tip.x = priv->pie_xc + (priv->pie_radius * cos (needle_pos));
tip.y = priv->pie_yc + (priv->pie_radius * sin (needle_pos));
cairo_move_to (cr, priv->pie_xc,priv->pie_yc);
cairo_line_to (cr, tip.x,tip.y);
cairo_stroke(cr);
cairo_destroy(cr);
}
