/* HSV color selector for GTK+
*
* Copyright (C) 1999 The Free Software Foundation
*
* Authors: Simon Budig <Simon.Budig@unix-ag.org> (original code)
* Federico Mena-Quintero <federico@gimp.org> (cleanup for GTK+)
* Jonathan Blandford <jrb@redhat.com> (cleanup for GTK+)
*
* 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 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, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GTK+ Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GTK+ at ftp://ftp.gtk.org/pub/gtk/.
*/
#include "config.h"
#define GDK_DISABLE_DEPRECATION_WARNINGS
#include <math.h>
#include <string.h>
#include "gtkhsv.h"
#include "gtkbindings.h"
#include "gtkmarshalers.h"
#include "gtkrender.h"
#include "gtkstylecontext.h"
#include "gtktypebuiltins.h"
#include "gtkintl.h"
/**
* SECTION:gtkhsv
* @Short_description: A “color wheel” widget
* @Title: GtkHSV
* @See_also: #GtkColorSelection, #GtkColorSelectionDialog
*
* #GtkHSV is the “color wheel” part of a complete color selector widget.
* It allows to select a color by determining its HSV components in an
* intuitive way. Moving the selection around the outer ring changes the hue,
* and moving the selection point inside the inner triangle changes value and
* saturation.
*
* #GtkHSV has been deprecated together with #GtkColorSelection, where
* it was used.
*/
/* Default width/height */
#define DEFAULT_SIZE 100
/* Default ring width */
#define DEFAULT_RING_WIDTH 10
/* Dragging modes */
typedef enum {
DRAG_NONE,
DRAG_H,
DRAG_SV
} DragMode;
/* Private part of the GtkHSV structure */
struct _GtkHSVPrivate
{
/* Color value */
double h;
double s;
double v;
/* Size and ring width */
int size;
int ring_width;
/* Window for capturing events */
GdkWindow *window;
/* Dragging mode */
DragMode mode;
guint focus_on_ring : 1;
};
/* Signal IDs */
enum {
CHANGED,
MOVE,
LAST_SIGNAL
};
static void gtk_hsv_destroy (GtkWidget *widget);
static void gtk_hsv_realize (GtkWidget *widget);
static void gtk_hsv_unrealize (GtkWidget *widget);
static void gtk_hsv_get_preferred_width (GtkWidget *widget,
gint *minimum,
gint *natural);
static void gtk_hsv_get_preferred_height (GtkWidget *widget,
gint *minimum,
gint *natural);
static void gtk_hsv_size_allocate (GtkWidget *widget,
GtkAllocation *allocation);
static gboolean gtk_hsv_button_press (GtkWidget *widget,
GdkEventButton *event);
static gboolean gtk_hsv_button_release (GtkWidget *widget,
GdkEventButton *event);
static gboolean gtk_hsv_motion (GtkWidget *widget,
GdkEventMotion *event);
static gboolean gtk_hsv_draw (GtkWidget *widget,
cairo_t *cr);
static gboolean gtk_hsv_grab_broken (GtkWidget *widget,
GdkEventGrabBroken *event);
static gboolean gtk_hsv_focus (GtkWidget *widget,
GtkDirectionType direction);
static void gtk_hsv_move (GtkHSV *hsv,
GtkDirectionType dir);
static guint hsv_signals[LAST_SIGNAL];
G_DEFINE_TYPE_WITH_PRIVATE (GtkHSV, gtk_hsv, GTK_TYPE_WIDGET)
/* Class initialization function for the HSV color selector */
static void
gtk_hsv_class_init (GtkHSVClass *class)
{
GObjectClass *gobject_class;
GtkWidgetClass *widget_class;
GtkHSVClass *hsv_class;
GtkBindingSet *binding_set;
gobject_class = (GObjectClass *) class;
widget_class = (GtkWidgetClass *) class;
hsv_class = GTK_HSV_CLASS (class);
widget_class->destroy = gtk_hsv_destroy;
widget_class->realize = gtk_hsv_realize;
widget_class->unrealize = gtk_hsv_unrealize;
widget_class->get_preferred_width = gtk_hsv_get_preferred_width;
widget_class->get_preferred_height = gtk_hsv_get_preferred_height;
widget_class->size_allocate = gtk_hsv_size_allocate;
widget_class->button_press_event = gtk_hsv_button_press;
widget_class->button_release_event = gtk_hsv_button_release;
widget_class->motion_notify_event = gtk_hsv_motion;
widget_class->draw = gtk_hsv_draw;
widget_class->focus = gtk_hsv_focus;
widget_class->grab_broken_event = gtk_hsv_grab_broken;
gtk_widget_class_set_accessible_role (widget_class, ATK_ROLE_COLOR_CHOOSER);
hsv_class->move = gtk_hsv_move;
hsv_signals[CHANGED] =
g_signal_new (I_("changed"),
G_OBJECT_CLASS_TYPE (gobject_class),
G_SIGNAL_RUN_FIRST,
G_STRUCT_OFFSET (GtkHSVClass, changed),
NULL, NULL,
NULL,
G_TYPE_NONE, 0);
hsv_signals[MOVE] =
g_signal_new (I_("move"),
G_OBJECT_CLASS_TYPE (gobject_class),
G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
G_STRUCT_OFFSET (GtkHSVClass, move),
NULL, NULL,
NULL,
G_TYPE_NONE, 1,
GTK_TYPE_DIRECTION_TYPE);
binding_set = gtk_binding_set_by_class (class);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_Up, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_UP);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_KP_Up, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_UP);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_Down, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_DOWN);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_KP_Down, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_DOWN);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_Right, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_RIGHT);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_KP_Right, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_RIGHT);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_Left, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_LEFT);
gtk_binding_entry_add_signal (binding_set, GDK_KEY_KP_Left, 0,
"move", 1,
G_TYPE_ENUM, GTK_DIR_LEFT);
}
static void
gtk_hsv_init (GtkHSV *hsv)
{
GtkHSVPrivate *priv;
priv = gtk_hsv_get_instance_private (hsv);
hsv->priv = priv;
gtk_widget_set_has_window (GTK_WIDGET (hsv), FALSE);
gtk_widget_set_can_focus (GTK_WIDGET (hsv), TRUE);
priv->h = 0.0;
priv->s = 0.0;
priv->v = 0.0;
priv->size = DEFAULT_SIZE;
priv->ring_width = DEFAULT_RING_WIDTH;
}
static void
gtk_hsv_destroy (GtkWidget *widget)
{
GTK_WIDGET_CLASS (gtk_hsv_parent_class)->destroy (widget);
}
static void
gtk_hsv_realize (GtkWidget *widget)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
GtkAllocation allocation;
GdkWindow *parent_window;
GdkWindowAttr attr;
int attr_mask;
gtk_widget_set_realized (widget, TRUE);
gtk_widget_get_allocation (widget, &allocation);
attr.window_type = GDK_WINDOW_CHILD;
attr.x = allocation.x;
attr.y = allocation.y;
attr.width = allocation.width;
attr.height = allocation.height;
attr.wclass = GDK_INPUT_ONLY;
attr.event_mask = gtk_widget_get_events (widget);
attr.event_mask |= (GDK_KEY_PRESS_MASK
| GDK_BUTTON_PRESS_MASK
| GDK_BUTTON_RELEASE_MASK
| GDK_POINTER_MOTION_MASK
| GDK_ENTER_NOTIFY_MASK
| GDK_LEAVE_NOTIFY_MASK);
attr_mask = GDK_WA_X | GDK_WA_Y;
parent_window = gtk_widget_get_parent_window (widget);
gtk_widget_set_window (widget, parent_window);
g_object_ref (parent_window);
priv->window = gdk_window_new (parent_window, &attr, attr_mask);
gdk_window_set_user_data (priv->window, hsv);
gdk_window_show (priv->window);
}
static void
gtk_hsv_unrealize (GtkWidget *widget)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
gdk_window_set_user_data (priv->window, NULL);
gdk_window_destroy (priv->window);
priv->window = NULL;
GTK_WIDGET_CLASS (gtk_hsv_parent_class)->unrealize (widget);
}
static void
gtk_hsv_get_preferred_width (GtkWidget *widget,
gint *minimum,
gint *natural)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
gint focus_width;
gint focus_pad;
gtk_widget_style_get (widget,
"focus-line-width", &focus_width,
"focus-padding", &focus_pad,
NULL);
*minimum = priv->size + 2 * (focus_width + focus_pad);
*natural = priv->size + 2 * (focus_width + focus_pad);
}
static void
gtk_hsv_get_preferred_height (GtkWidget *widget,
gint *minimum,
gint *natural)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
gint focus_width;
gint focus_pad;
gtk_widget_style_get (widget,
"focus-line-width", &focus_width,
"focus-padding", &focus_pad,
NULL);
*minimum = priv->size + 2 * (focus_width + focus_pad);
*natural = priv->size + 2 * (focus_width + focus_pad);
}
static void
gtk_hsv_size_allocate (GtkWidget *widget,
GtkAllocation *allocation)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
gtk_widget_set_allocation (widget, allocation);
if (gtk_widget_get_realized (widget))
gdk_window_move_resize (priv->window,
allocation->x,
allocation->y,
allocation->width,
allocation->height);
}
/* Utility functions */
#define INTENSITY(r, g, b) ((r) * 0.30 + (g) * 0.59 + (b) * 0.11)
/* Converts from HSV to RGB */
static void
hsv_to_rgb (gdouble *h,
gdouble *s,
gdouble *v)
{
gdouble hue, saturation, value;
gdouble f, p, q, t;
if (*s == 0.0)
{
*h = *v;
*s = *v;
*v = *v; /* heh */
}
else
{
hue = *h * 6.0;
saturation = *s;
value = *v;
if (hue == 6.0)
hue = 0.0;
f = hue - (int) hue;
p = value * (1.0 - saturation);
q = value * (1.0 - saturation * f);
t = value * (1.0 - saturation * (1.0 - f));
switch ((int) hue)
{
case 0:
*h = value;
*s = t;
*v = p;
break;
case 1:
*h = q;
*s = value;
*v = p;
break;
case 2:
*h = p;
*s = value;
*v = t;
break;
case 3:
*h = p;
*s = q;
*v = value;
break;
case 4:
*h = t;
*s = p;
*v = value;
break;
case 5:
*h = value;
*s = p;
*v = q;
break;
default:
g_assert_not_reached ();
}
}
}
/* Computes the vertices of the saturation/value triangle */
static void
compute_triangle (GtkHSV *hsv,
gint *hx,
gint *hy,
gint *sx,
gint *sy,
gint *vx,
gint *vy)
{
GtkHSVPrivate *priv = hsv->priv;
GtkWidget *widget = GTK_WIDGET (hsv);
gdouble center_x;
gdouble center_y;
gdouble inner, outer;
gdouble angle;
center_x = gtk_widget_get_allocated_width (widget) / 2.0;
center_y = gtk_widget_get_allocated_height (widget) / 2.0;
outer = priv->size / 2.0;
inner = outer - priv->ring_width;
angle = priv->h * 2.0 * G_PI;
*hx = floor (center_x + cos (angle) * inner + 0.5);
*hy = floor (center_y - sin (angle) * inner + 0.5);
*sx = floor (center_x + cos (angle + 2.0 * G_PI / 3.0) * inner + 0.5);
*sy = floor (center_y - sin (angle + 2.0 * G_PI / 3.0) * inner + 0.5);
*vx = floor (center_x + cos (angle + 4.0 * G_PI / 3.0) * inner + 0.5);
*vy = floor (center_y - sin (angle + 4.0 * G_PI / 3.0) * inner + 0.5);
}
/* Computes whether a point is inside the hue ring */
static gboolean
is_in_ring (GtkHSV *hsv,
gdouble x,
gdouble y)
{
GtkHSVPrivate *priv = hsv->priv;
GtkWidget *widget = GTK_WIDGET (hsv);
gdouble dx, dy, dist;
gdouble center_x;
gdouble center_y;
gdouble inner, outer;
center_x = gtk_widget_get_allocated_width (widget) / 2.0;
center_y = gtk_widget_get_allocated_height (widget) / 2.0;
outer = priv->size / 2.0;
inner = outer - priv->ring_width;
dx = x - center_x;
dy = center_y - y;
dist = dx * dx + dy * dy;
return (dist >= inner * inner && dist <= outer * outer);
}
/* Computes a saturation/value pair based on the mouse coordinates */
static void
compute_sv (GtkHSV *hsv,
gdouble x,
gdouble y,
gdouble *s,
gdouble *v)
{
GtkWidget *widget = GTK_WIDGET (hsv);
int ihx, ihy, isx, isy, ivx, ivy;
double hx, hy, sx, sy, vx, vy;
double center_x;
double center_y;
compute_triangle (hsv, &ihx, &ihy, &isx, &isy, &ivx, &ivy);
center_x = gtk_widget_get_allocated_width (widget) / 2.0;
center_y = gtk_widget_get_allocated_height (widget) / 2.0;
hx = ihx - center_x;
hy = center_y - ihy;
sx = isx - center_x;
sy = center_y - isy;
vx = ivx - center_x;
vy = center_y - ivy;
x -= center_x;
y = center_y - y;
if (vx * (x - sx) + vy * (y - sy) < 0.0)
{
*s = 1.0;
*v = (((x - sx) * (hx - sx) + (y - sy) * (hy-sy))
/ ((hx - sx) * (hx - sx) + (hy - sy) * (hy - sy)));
if (*v < 0.0)
*v = 0.0;
else if (*v > 1.0)
*v = 1.0;
}
else if (hx * (x - sx) + hy * (y - sy) < 0.0)
{
*s = 0.0;
*v = (((x - sx) * (vx - sx) + (y - sy) * (vy - sy))
/ ((vx - sx) * (vx - sx) + (vy - sy) * (vy - sy)));
if (*v < 0.0)
*v = 0.0;
else if (*v > 1.0)
*v = 1.0;
}
else if (sx * (x - hx) + sy * (y - hy) < 0.0)
{
*v = 1.0;
*s = (((x - vx) * (hx - vx) + (y - vy) * (hy - vy)) /
((hx - vx) * (hx - vx) + (hy - vy) * (hy - vy)));
if (*s < 0.0)
*s = 0.0;
else if (*s > 1.0)
*s = 1.0;
}
else
{
*v = (((x - sx) * (hy - vy) - (y - sy) * (hx - vx))
/ ((vx - sx) * (hy - vy) - (vy - sy) * (hx - vx)));
if (*v<= 0.0)
{
*v = 0.0;
*s = 0.0;
}
else
{
if (*v > 1.0)
*v = 1.0;
if (fabs (hy - vy) < fabs (hx - vx))
*s = (x - sx - *v * (vx - sx)) / (*v * (hx - vx));
else
*s = (y - sy - *v * (vy - sy)) / (*v * (hy - vy));
if (*s < 0.0)
*s = 0.0;
else if (*s > 1.0)
*s = 1.0;
}
}
}
/* Computes whether a point is inside the saturation/value triangle */
static gboolean
is_in_triangle (GtkHSV *hsv,
gdouble x,
gdouble y)
{
int hx, hy, sx, sy, vx, vy;
double det, s, v;
compute_triangle (hsv, &hx, &hy, &sx, &sy, &vx, &vy);
det = (vx - sx) * (hy - sy) - (vy - sy) * (hx - sx);
s = ((x - sx) * (hy - sy) - (y - sy) * (hx - sx)) / det;
v = ((vx - sx) * (y - sy) - (vy - sy) * (x - sx)) / det;
return (s >= 0.0 && v >= 0.0 && s + v <= 1.0);
}
/* Computes a value based on the mouse coordinates */
static double
compute_v (GtkHSV *hsv,
gdouble x,
gdouble y)
{
GtkWidget *widget = GTK_WIDGET (hsv);
double center_x;
double center_y;
double dx, dy;
double angle;
center_x = gtk_widget_get_allocated_width (widget) / 2.0;
center_y = gtk_widget_get_allocated_height (widget) / 2.0;
dx = x - center_x;
dy = center_y - y;
angle = atan2 (dy, dx);
if (angle < 0.0)
angle += 2.0 * G_PI;
return angle / (2.0 * G_PI);
}
/* Event handlers */
static void
set_cross_grab (GtkHSV *hsv,
GdkDevice *device,
guint32 time)
{
GtkHSVPrivate *priv = hsv->priv;
GdkCursor *cursor;
cursor = gdk_cursor_new_for_display (gtk_widget_get_display (GTK_WIDGET (hsv)),
GDK_CROSSHAIR);
gdk_device_grab (device,
priv->window,
GDK_OWNERSHIP_NONE,
FALSE,
GDK_POINTER_MOTION_MASK
| GDK_POINTER_MOTION_HINT_MASK
| GDK_BUTTON_RELEASE_MASK,
cursor,
time);
g_object_unref (cursor);
}
static gboolean
gtk_hsv_grab_broken (GtkWidget *widget,
GdkEventGrabBroken *event)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
priv->mode = DRAG_NONE;
return TRUE;
}
static gint
gtk_hsv_button_press (GtkWidget *widget,
GdkEventButton *event)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
double x, y;
if (priv->mode != DRAG_NONE || event->button != GDK_BUTTON_PRIMARY)
return FALSE;
x = event->x;
y = event->y;
if (is_in_ring (hsv, x, y))
{
priv->mode = DRAG_H;
set_cross_grab (hsv, gdk_event_get_device ((GdkEvent *) event), event->time);
gtk_hsv_set_color (hsv,
compute_v (hsv, x, y),
priv->s,
priv->v);
gtk_widget_grab_focus (widget);
priv->focus_on_ring = TRUE;
return TRUE;
}
if (is_in_triangle (hsv, x, y))
{
gdouble s, v;
priv->mode = DRAG_SV;
set_cross_grab (hsv, gdk_event_get_device ((GdkEvent *) event), event->time);
compute_sv (hsv, x, y, &s, &v);
gtk_hsv_set_color (hsv, priv->h, s, v);
gtk_widget_grab_focus (widget);
priv->focus_on_ring = FALSE;
return TRUE;
}
return FALSE;
}
static gint
gtk_hsv_button_release (GtkWidget *widget,
GdkEventButton *event)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
DragMode mode;
gdouble x, y;
if (priv->mode == DRAG_NONE || event->button != GDK_BUTTON_PRIMARY)
return FALSE;
/* Set the drag mode to DRAG_NONE so that signal handlers for "catched"
* can see that this is the final color state.
*/
mode = priv->mode;
priv->mode = DRAG_NONE;
x = event->x;
y = event->y;
if (mode == DRAG_H)
{
gtk_hsv_set_color (hsv, compute_v (hsv, x, y), priv->s, priv->v);
}
else if (mode == DRAG_SV)
{
gdouble s, v;
compute_sv (hsv, x, y, &s, &v);
gtk_hsv_set_color (hsv, priv->h, s, v);
}
else
{
g_assert_not_reached ();
}
gdk_device_ungrab (gdk_event_get_device ((GdkEvent *) event), event->time);
return TRUE;
}
static gint
gtk_hsv_motion (GtkWidget *widget,
GdkEventMotion *event)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
gdouble x, y;
if (priv->mode == DRAG_NONE)
return FALSE;
gdk_event_request_motions (event);
x = event->x;
y = event->y;
if (priv->mode == DRAG_H)
{
gtk_hsv_set_color (hsv, compute_v (hsv, x, y), priv->s, priv->v);
return TRUE;
}
else if (priv->mode == DRAG_SV)
{
gdouble s, v;
compute_sv (hsv, x, y, &s, &v);
gtk_hsv_set_color (hsv, priv->h, s, v);
return TRUE;
}
g_assert_not_reached ();
return FALSE;
}
/* Redrawing */
/* Paints the hue ring */
static void
paint_ring (GtkHSV *hsv,
cairo_t *cr)
{
GtkHSVPrivate *priv = hsv->priv;
GtkWidget *widget = GTK_WIDGET (hsv);
int xx, yy, width, height;
gdouble dx, dy, dist;
gdouble center_x;
gdouble center_y;
gdouble inner, outer;
guint32 *buf, *p;
gdouble angle;
gdouble hue;
gdouble r, g, b;
cairo_surface_t *source;
cairo_t *source_cr;
gint stride;
width = gtk_widget_get_allocated_width (widget);
height = gtk_widget_get_allocated_height (widget);
center_x = width / 2.0;
center_y = height / 2.0;
outer = priv->size / 2.0;
inner = outer - priv->ring_width;
/* Create an image initialized with the ring colors */
stride = cairo_format_stride_for_width (CAIRO_FORMAT_RGB24, width);
buf = g_new (guint32, height * stride / 4);
for (yy = 0; yy < height; yy++)
{
p = buf + yy * width;
dy = -(yy - center_y);
for (xx = 0; xx < width; xx++)
{
dx = xx - center_x;
dist = dx * dx + dy * dy;
if (dist < ((inner-1) * (inner-1)) || dist > ((outer+1) * (outer+1)))
{
*p++ = 0;
continue;
}
angle = atan2 (dy, dx);
if (angle < 0.0)
angle += 2.0 * G_PI;
hue = angle / (2.0 * G_PI);
r = hue;
g = 1.0;
b = 1.0;
hsv_to_rgb (&r, &g, &b);
*p++ = (((int)floor (r * 255 + 0.5) << 16) |
((int)floor (g * 255 + 0.5) << 8) |
(int)floor (b * 255 + 0.5));
}
}
source = cairo_image_surface_create_for_data ((unsigned char *)buf,
CAIRO_FORMAT_RGB24,
width, height, stride);
/* Now draw the value marker onto the source image, so that it
* will get properly clipped at the edges of the ring
*/
source_cr = cairo_create (source);
r = priv->h;
g = 1.0;
b = 1.0;
hsv_to_rgb (&r, &g, &b);
if (INTENSITY (r, g, b) > 0.5)
cairo_set_source_rgb (source_cr, 0., 0., 0.);
else
cairo_set_source_rgb (source_cr, 1., 1., 1.);
cairo_move_to (source_cr, center_x, center_y);
cairo_line_to (source_cr,
center_x + cos (priv->h * 2.0 * G_PI) * priv->size / 2,
center_y - sin (priv->h * 2.0 * G_PI) * priv->size / 2);
cairo_stroke (source_cr);
cairo_destroy (source_cr);
/* Draw the ring using the source image */
cairo_save (cr);
cairo_set_source_surface (cr, source, 0, 0);
cairo_surface_destroy (source);
cairo_set_line_width (cr, priv->ring_width);
cairo_new_path (cr);
cairo_arc (cr,
center_x, center_y,
priv->size / 2. - priv->ring_width / 2.,
0, 2 * G_PI);
cairo_stroke (cr);
cairo_restore (cr);
g_free (buf);
}
/* Converts an HSV triplet to an integer RGB triplet */
static void
get_color (gdouble h,
gdouble s,
gdouble v,
gint *r,
gint *g,
gint *b)
{
hsv_to_rgb (&h, &s, &v);
*r = floor (h * 255 + 0.5);
*g = floor (s * 255 + 0.5);
*b = floor (v * 255 + 0.5);
}
#define SWAP(a, b, t) ((t) = (a), (a) = (b), (b) = (t))
#define LERP(a, b, v1, v2, i) (((v2) - (v1) != 0) \
? ((a) + ((b) - (a)) * ((i) - (v1)) / ((v2) - (v1))) \
: (a))
/* Number of pixels we extend out from the edges when creating
* color source to avoid artifacts
*/
#define PAD 3
/* Paints the HSV triangle */
static void
paint_triangle (GtkHSV *hsv,
cairo_t *cr,
gboolean draw_focus)
{
GtkHSVPrivate *priv = hsv->priv;
GtkWidget *widget = GTK_WIDGET (hsv);
gint hx, hy, sx, sy, vx, vy; /* HSV vertices */
gint x1, y1, r1, g1, b1; /* First vertex in scanline order */
gint x2, y2, r2, g2, b2; /* Second vertex */
gint x3, y3, r3, g3, b3; /* Third vertex */
gint t;
guint32 *buf, *p, c;
gint xl, xr, rl, rr, gl, gr, bl, br; /* Scanline data */
gint xx, yy;
gint x_interp, y_interp;
gint x_start, x_end;
cairo_surface_t *source;
gdouble r, g, b;
gint stride;
int width, height;
GtkStyleContext *context;
priv = hsv->priv;
width = gtk_widget_get_allocated_width (widget);
height = gtk_widget_get_allocated_height (widget);
/* Compute triangle's vertices */
compute_triangle (hsv, &hx, &hy, &sx, &sy, &vx, &vy);
x1 = hx;
y1 = hy;
get_color (priv->h, 1.0, 1.0, &r1, &g1, &b1);
x2 = sx;
y2 = sy;
get_color (priv->h, 1.0, 0.0, &r2, &g2, &b2);
x3 = vx;
y3 = vy;
get_color (priv->h, 0.0, 1.0, &r3, &g3, &b3);
if (y2 > y3)
{
SWAP (x2, x3, t);
SWAP (y2, y3, t);
SWAP (r2, r3, t);
SWAP (g2, g3, t);
SWAP (b2, b3, t);
}
if (y1 > y3)
{
SWAP (x1, x3, t);
SWAP (y1, y3, t);
SWAP (r1, r3, t);
SWAP (g1, g3, t);
SWAP (b1, b3, t);
}
if (y1 > y2)
{
SWAP (x1, x2, t);
SWAP (y1, y2, t);
SWAP (r1, r2, t);
SWAP (g1, g2, t);
SWAP (b1, b2, t);
}
/* Shade the triangle */
stride = cairo_format_stride_for_width (CAIRO_FORMAT_RGB24, width);
buf = g_new (guint32, height * stride / 4);
for (yy = 0; yy < height; yy++)
{
p = buf + yy * width;
if (yy >= y1 - PAD && yy < y3 + PAD) {
y_interp = CLAMP (yy, y1, y3);
if (y_interp < y2)
{
xl = LERP (x1, x2, y1, y2, y_interp);
rl = LERP (r1, r2, y1, y2, y_interp);
gl = LERP (g1, g2, y1, y2, y_interp);
bl = LERP (b1, b2, y1, y2, y_interp);
}
else
{
xl = LERP (x2, x3, y2, y3, y_interp);
rl = LERP (r2, r3, y2, y3, y_interp);
gl = LERP (g2, g3, y2, y3, y_interp);
bl = LERP (b2, b3, y2, y3, y_interp);
}
xr = LERP (x1, x3, y1, y3, y_interp);
rr = LERP (r1, r3, y1, y3, y_interp);
gr = LERP (g1, g3, y1, y3, y_interp);
br = LERP (b1, b3, y1, y3, y_interp);
if (xl > xr)
{
SWAP (xl, xr, t);
SWAP (rl, rr, t);
SWAP (gl, gr, t);
SWAP (bl, br, t);
}
x_start = MAX (xl - PAD, 0);
x_end = MIN (xr + PAD, width);
x_start = MIN (x_start, x_end);
c = (rl << 16) | (gl << 8) | bl;
for (xx = 0; xx < x_start; xx++)
*p++ = c;
for (; xx < x_end; xx++)
{
x_interp = CLAMP (xx, xl, xr);
*p++ = ((LERP (rl, rr, xl, xr, x_interp) << 16) |
(LERP (gl, gr, xl, xr, x_interp) << 8) |
LERP (bl, br, xl, xr, x_interp));
}
c = (rr << 16) | (gr << 8) | br;
for (; xx < width; xx++)
*p++ = c;
}
}
source = cairo_image_surface_create_for_data ((unsigned char *)buf,
CAIRO_FORMAT_RGB24,
width, height, stride);
/* Draw a triangle with the image as a source */
cairo_set_source_surface (cr, source, 0, 0);
cairo_surface_destroy (source);
cairo_move_to (cr, x1, y1);
cairo_line_to (cr, x2, y2);
cairo_line_to (cr, x3, y3);
cairo_close_path (cr);
cairo_fill (cr);
g_free (buf);
/* Draw value marker */
xx = floor (sx + (vx - sx) * priv->v + (hx - vx) * priv->s * priv->v + 0.5);
yy = floor (sy + (vy - sy) * priv->v + (hy - vy) * priv->s * priv->v + 0.5);
r = priv->h;
g = priv->s;
b = priv->v;
hsv_to_rgb (&r, &g, &b);
context = gtk_widget_get_style_context (widget);
gtk_style_context_save (context);
if (INTENSITY (r, g, b) > 0.5)
{
gtk_style_context_add_class (context, "light-area-focus");
cairo_set_source_rgb (cr, 0., 0., 0.);
}
else
{
gtk_style_context_add_class (context, "dark-area-focus");
cairo_set_source_rgb (cr, 1., 1., 1.);
}
#define RADIUS 4
#define FOCUS_RADIUS 6
cairo_new_path (cr);
cairo_arc (cr, xx, yy, RADIUS, 0, 2 * G_PI);
cairo_stroke (cr);
/* Draw focus outline */
if (draw_focus && !priv->focus_on_ring)
{
gint focus_width;
gint focus_pad;
gtk_widget_style_get (widget,
"focus-line-width", &focus_width,
"focus-padding", &focus_pad,
NULL);
gtk_render_focus (context, cr,
xx - FOCUS_RADIUS - focus_width - focus_pad,
yy - FOCUS_RADIUS - focus_width - focus_pad,
2 * (FOCUS_RADIUS + focus_width + focus_pad),
2 * (FOCUS_RADIUS + focus_width + focus_pad));
}
gtk_style_context_restore (context);
}
/* Paints the contents of the HSV color selector */
static gboolean
gtk_hsv_draw (GtkWidget *widget,
cairo_t *cr)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
gboolean draw_focus;
draw_focus = gtk_widget_has_visible_focus (widget);
paint_ring (hsv, cr);
paint_triangle (hsv, cr, draw_focus);
if (draw_focus && priv->focus_on_ring)
{
GtkStyleContext *context;
context = gtk_widget_get_style_context (widget);
gtk_render_focus (context, cr, 0, 0,
gtk_widget_get_allocated_width (widget),
gtk_widget_get_allocated_height (widget));
}
return FALSE;
}
static gboolean
gtk_hsv_focus (GtkWidget *widget,
GtkDirectionType dir)
{
GtkHSV *hsv = GTK_HSV (widget);
GtkHSVPrivate *priv = hsv->priv;
if (!gtk_widget_has_focus (widget))
{
if (dir == GTK_DIR_TAB_BACKWARD)
priv->focus_on_ring = FALSE;
else
priv->focus_on_ring = TRUE;
gtk_widget_grab_focus (GTK_WIDGET (hsv));
return TRUE;
}
switch (dir)
{
case GTK_DIR_UP:
if (priv->focus_on_ring)
return FALSE;
else
priv->focus_on_ring = TRUE;
break;
case GTK_DIR_DOWN:
if (priv->focus_on_ring)
priv->focus_on_ring = FALSE;
else
return FALSE;
break;
case GTK_DIR_LEFT:
case GTK_DIR_TAB_BACKWARD:
if (priv->focus_on_ring)
return FALSE;
else
priv->focus_on_ring = TRUE;
break;
case GTK_DIR_RIGHT:
case GTK_DIR_TAB_FORWARD:
if (priv->focus_on_ring)
priv->focus_on_ring = FALSE;
else
return FALSE;
break;
}
gtk_widget_queue_draw (GTK_WIDGET (hsv));
return TRUE;
}
/**
* gtk_hsv_new:
*
* Creates a new HSV color selector.
*
* Returns: A newly-created HSV color selector.
*
* Since: 2.14
*/
GtkWidget*
gtk_hsv_new (void)
{
return g_object_new (GTK_TYPE_HSV, NULL);
}
/**
* gtk_hsv_set_color:
* @hsv: An HSV color selector
* @h: Hue
* @s: Saturation
* @v: Value
*
* Sets the current color in an HSV color selector.
* Color component values must be in the [0.0, 1.0] range.
*
* Since: 2.14
*/
void
gtk_hsv_set_color (GtkHSV *hsv,
gdouble h,
gdouble s,
gdouble v)
{
GtkHSVPrivate *priv;
g_return_if_fail (GTK_IS_HSV (hsv));
g_return_if_fail (h >= 0.0 && h <= 1.0);
g_return_if_fail (s >= 0.0 && s <= 1.0);
g_return_if_fail (v >= 0.0 && v <= 1.0);
priv = hsv->priv;
priv->h = h;
priv->s = s;
priv->v = v;
g_signal_emit (hsv, hsv_signals[CHANGED], 0);
gtk_widget_queue_draw (GTK_WIDGET (hsv));
}
/**
* gtk_hsv_get_color:
* @hsv: An HSV color selector
* @h: (out): Return value for the hue
* @s: (out): Return value for the saturation
* @v: (out): Return value for the value
*
* Queries the current color in an HSV color selector.
* Returned values will be in the [0.0, 1.0] range.
*
* Since: 2.14
*/
void
gtk_hsv_get_color (GtkHSV *hsv,
double *h,
double *s,
double *v)
{
GtkHSVPrivate *priv;
g_return_if_fail (GTK_IS_HSV (hsv));
priv = hsv->priv;
if (h)
*h = priv->h;
if (s)
*s = priv->s;
if (v)
*v = priv->v;
}
/**
* gtk_hsv_set_metrics:
* @hsv: An HSV color selector
* @size: Diameter for the hue ring
* @ring_width: Width of the hue ring
*
* Sets the size and ring width of an HSV color selector.
*
* Since: 2.14
*/
void
gtk_hsv_set_metrics (GtkHSV *hsv,
gint size,
gint ring_width)
{
GtkHSVPrivate *priv;
int same_size;
g_return_if_fail (GTK_IS_HSV (hsv));
g_return_if_fail (size > 0);
g_return_if_fail (ring_width > 0);
g_return_if_fail (2 * ring_width + 1 <= size);
priv = hsv->priv;
same_size = (priv->size == size);
priv->size = size;
priv->ring_width = ring_width;
if (same_size)
gtk_widget_queue_draw (GTK_WIDGET (hsv));
else
gtk_widget_queue_resize (GTK_WIDGET (hsv));
}
/**
* gtk_hsv_get_metrics:
* @hsv: An HSV color selector
* @size: (out): Return value for the diameter of the hue ring
* @ring_width: (out): Return value for the width of the hue ring
*
* Queries the size and ring width of an HSV color selector.
*
* Since: 2.14
*/
void
gtk_hsv_get_metrics (GtkHSV *hsv,
gint *size,
gint *ring_width)
{
GtkHSVPrivate *priv;
g_return_if_fail (GTK_IS_HSV (hsv));
priv = hsv->priv;
if (size)
*size = priv->size;
if (ring_width)
*ring_width = priv->ring_width;
}
/**
* gtk_hsv_is_adjusting:
* @hsv: A #GtkHSV
*
* An HSV color selector can be said to be adjusting if multiple rapid
* changes are being made to its value, for example, when the user is
* adjusting the value with the mouse. This function queries whether
* the HSV color selector is being adjusted or not.
*
* Returns: %TRUE if clients can ignore changes to the color value,
* since they may be transitory, or %FALSE if they should consider
* the color value status to be final.
*
* Since: 2.14
*/
gboolean
gtk_hsv_is_adjusting (GtkHSV *hsv)
{
GtkHSVPrivate *priv;
g_return_val_if_fail (GTK_IS_HSV (hsv), FALSE);
priv = hsv->priv;
return priv->mode != DRAG_NONE;
}
static void
gtk_hsv_move (GtkHSV *hsv,
GtkDirectionType dir)
{
GtkHSVPrivate *priv = hsv->priv;
gdouble hue, sat, val;
gint hx, hy, sx, sy, vx, vy; /* HSV vertices */
gint x, y; /* position in triangle */
hue = priv->h;
sat = priv->s;
val = priv->v;
compute_triangle (hsv, &hx, &hy, &sx, &sy, &vx, &vy);
x = floor (sx + (vx - sx) * priv->v + (hx - vx) * priv->s * priv->v + 0.5);
y = floor (sy + (vy - sy) * priv->v + (hy - vy) * priv->s * priv->v + 0.5);
#define HUE_DELTA 0.002
switch (dir)
{
case GTK_DIR_UP:
if (priv->focus_on_ring)
hue += HUE_DELTA;
else
{
y -= 1;
compute_sv (hsv, x, y, &sat, &val);
}
break;
case GTK_DIR_DOWN:
if (priv->focus_on_ring)
hue -= HUE_DELTA;
else
{
y += 1;
compute_sv (hsv, x, y, &sat, &val);
}
break;
case GTK_DIR_LEFT:
if (priv->focus_on_ring)
hue += HUE_DELTA;
else
{
x -= 1;
compute_sv (hsv, x, y, &sat, &val);
}
break;
case GTK_DIR_RIGHT:
if (priv->focus_on_ring)
hue -= HUE_DELTA
;
else
{
x += 1;
compute_sv (hsv, x, y, &sat, &val);
}
break;
default:
/* we don't care about the tab directions */
break;
}
/* Wrap */
if (hue < 0.0)
hue = 1.0;
else if (hue > 1.0)
hue = 0.0;
gtk_hsv_set_color (hsv, hue, sat, val);
}