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-rw-r--r--libmate-desktop/mate-hsv.c1441
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diff --git a/libmate-desktop/mate-hsv.c b/libmate-desktop/mate-hsv.c
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+/* HSV color selector for GTK+
+ *
+ * Copyright (C) 1999 The Free Software Foundation
+ *
+ * Authors: Simon Budig <[email protected]> (original code)
+ * Federico Mena-Quintero <[email protected]> (cleanup for GTK+)
+ * Jonathan Blandford <[email protected]> (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/.
+ *
+ * Modified to work internally in mate-desktop by Pablo Barciela 2019
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "mate-hsv.h"
+
+#include <math.h>
+#include <string.h>
+
+#include <gtk/gtk.h>
+
+#define I_(string) g_intern_static_string (string)
+
+/**
+ * SECTION:mate-hsv
+ * @Short_description: A “color wheel” widget
+ * @Title: MateHSV
+ *
+ * #MateHSV 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.
+ */
+
+/* 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 MateHSV structure */
+struct _MateHSVPrivate
+{
+ /* 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 mate_hsv_destroy (GtkWidget *widget);
+static void mate_hsv_realize (GtkWidget *widget);
+static void mate_hsv_unrealize (GtkWidget *widget);
+static void mate_hsv_get_preferred_width (GtkWidget *widget,
+ gint *minimum,
+ gint *natural);
+static void mate_hsv_get_preferred_height (GtkWidget *widget,
+ gint *minimum,
+ gint *natural);
+static void mate_hsv_size_allocate (GtkWidget *widget,
+ GtkAllocation *allocation);
+static gboolean mate_hsv_button_press (GtkWidget *widget,
+ GdkEventButton *event);
+static gboolean mate_hsv_button_release (GtkWidget *widget,
+ GdkEventButton *event);
+static gboolean mate_hsv_motion (GtkWidget *widget,
+ GdkEventMotion *event);
+static gboolean mate_hsv_draw (GtkWidget *widget,
+ cairo_t *cr);
+static gboolean mate_hsv_grab_broken (GtkWidget *widget,
+ GdkEventGrabBroken *event);
+static gboolean mate_hsv_focus (GtkWidget *widget,
+ GtkDirectionType direction);
+static void mate_hsv_move (MateHSV *hsv,
+ GtkDirectionType dir);
+
+static guint hsv_signals[LAST_SIGNAL];
+
+G_DEFINE_TYPE_WITH_PRIVATE (MateHSV, mate_hsv, GTK_TYPE_WIDGET)
+
+/* Class initialization function for the HSV color selector */
+static void
+mate_hsv_class_init (MateHSVClass *class)
+{
+ GObjectClass *gobject_class;
+ GtkWidgetClass *widget_class;
+ MateHSVClass *hsv_class;
+ GtkBindingSet *binding_set;
+
+ gobject_class = (GObjectClass *) class;
+ widget_class = (GtkWidgetClass *) class;
+ hsv_class = MATE_HSV_CLASS (class);
+
+ widget_class->destroy = mate_hsv_destroy;
+ widget_class->realize = mate_hsv_realize;
+ widget_class->unrealize = mate_hsv_unrealize;
+ widget_class->get_preferred_width = mate_hsv_get_preferred_width;
+ widget_class->get_preferred_height = mate_hsv_get_preferred_height;
+ widget_class->size_allocate = mate_hsv_size_allocate;
+ widget_class->button_press_event = mate_hsv_button_press;
+ widget_class->button_release_event = mate_hsv_button_release;
+ widget_class->motion_notify_event = mate_hsv_motion;
+ widget_class->draw = mate_hsv_draw;
+ widget_class->focus = mate_hsv_focus;
+ widget_class->grab_broken_event = mate_hsv_grab_broken;
+
+ gtk_widget_class_set_accessible_role (widget_class, ATK_ROLE_COLOR_CHOOSER);
+
+ hsv_class->move = mate_hsv_move;
+
+ hsv_signals[CHANGED] =
+ g_signal_new (I_("changed"),
+ G_OBJECT_CLASS_TYPE (gobject_class),
+ G_SIGNAL_RUN_FIRST,
+ G_STRUCT_OFFSET (MateHSVClass, 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 (MateHSVClass, 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
+mate_hsv_init (MateHSV *hsv)
+{
+ MateHSVPrivate *priv;
+
+ priv = mate_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
+mate_hsv_destroy (GtkWidget *widget)
+{
+ GTK_WIDGET_CLASS (mate_hsv_parent_class)->destroy (widget);
+}
+
+static void
+mate_hsv_realize (GtkWidget *widget)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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
+mate_hsv_unrealize (GtkWidget *widget)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *priv = hsv->priv;
+
+ gdk_window_set_user_data (priv->window, NULL);
+ gdk_window_destroy (priv->window);
+ priv->window = NULL;
+
+ GTK_WIDGET_CLASS (mate_hsv_parent_class)->unrealize (widget);
+}
+
+static void
+mate_hsv_get_preferred_width (GtkWidget *widget,
+ gint *minimum,
+ gint *natural)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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
+mate_hsv_get_preferred_height (GtkWidget *widget,
+ gint *minimum,
+ gint *natural)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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
+mate_hsv_size_allocate (GtkWidget *widget,
+ GtkAllocation *allocation)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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 (MateHSV *hsv,
+ gint *hx,
+ gint *hy,
+ gint *sx,
+ gint *sy,
+ gint *vx,
+ gint *vy)
+{
+ MateHSVPrivate *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 (MateHSV *hsv,
+ gdouble x,
+ gdouble y)
+{
+ MateHSVPrivate *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 (MateHSV *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 (MateHSV *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 (MateHSV *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 (MateHSV *hsv,
+ GdkDevice *device,
+ guint32 time)
+{
+ MateHSVPrivate *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
+mate_hsv_grab_broken (GtkWidget *widget,
+ GdkEventGrabBroken *event)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *priv = hsv->priv;
+
+ priv->mode = DRAG_NONE;
+
+ return TRUE;
+}
+
+static gint
+mate_hsv_button_press (GtkWidget *widget,
+ GdkEventButton *event)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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);
+
+ mate_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);
+ mate_hsv_set_color (hsv, priv->h, s, v);
+
+ gtk_widget_grab_focus (widget);
+ priv->focus_on_ring = FALSE;
+
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+static gint
+mate_hsv_button_release (GtkWidget *widget,
+ GdkEventButton *event)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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)
+ {
+ mate_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);
+ mate_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
+mate_hsv_motion (GtkWidget *widget,
+ GdkEventMotion *event)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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)
+ {
+ mate_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);
+ mate_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 (MateHSV *hsv,
+ cairo_t *cr)
+{
+ MateHSVPrivate *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 (MateHSV *hsv,
+ cairo_t *cr,
+ gboolean draw_focus)
+{
+ MateHSVPrivate *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
+mate_hsv_draw (GtkWidget *widget,
+ cairo_t *cr)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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
+mate_hsv_focus (GtkWidget *widget,
+ GtkDirectionType dir)
+{
+ MateHSV *hsv = MATE_HSV (widget);
+ MateHSVPrivate *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;
+}
+
+/**
+ * mate_hsv_new:
+ *
+ * Creates a new HSV color selector.
+ *
+ * Returns: A newly-created HSV color selector.
+ */
+GtkWidget*
+mate_hsv_new (void)
+{
+ return g_object_new (MATE_TYPE_HSV, NULL);
+}
+
+/**
+ * mate_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.
+ */
+void
+mate_hsv_set_color (MateHSV *hsv,
+ gdouble h,
+ gdouble s,
+ gdouble v)
+{
+ MateHSVPrivate *priv;
+
+ g_return_if_fail (MATE_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));
+}
+
+/**
+ * mate_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.
+ */
+void
+mate_hsv_get_color (MateHSV *hsv,
+ double *h,
+ double *s,
+ double *v)
+{
+ MateHSVPrivate *priv;
+
+ g_return_if_fail (MATE_IS_HSV (hsv));
+
+ priv = hsv->priv;
+
+ if (h)
+ *h = priv->h;
+
+ if (s)
+ *s = priv->s;
+
+ if (v)
+ *v = priv->v;
+}
+
+/**
+ * mate_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.
+ */
+void
+mate_hsv_set_metrics (MateHSV *hsv,
+ gint size,
+ gint ring_width)
+{
+ MateHSVPrivate *priv;
+ int same_size;
+
+ g_return_if_fail (MATE_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));
+}
+
+/**
+ * mate_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.
+ */
+void
+mate_hsv_get_metrics (MateHSV *hsv,
+ gint *size,
+ gint *ring_width)
+{
+ MateHSVPrivate *priv;
+
+ g_return_if_fail (MATE_IS_HSV (hsv));
+
+ priv = hsv->priv;
+
+ if (size)
+ *size = priv->size;
+
+ if (ring_width)
+ *ring_width = priv->ring_width;
+}
+
+/**
+ * mate_hsv_is_adjusting:
+ * @hsv: A #MateHSV
+ *
+ * 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.
+ */
+gboolean
+mate_hsv_is_adjusting (MateHSV *hsv)
+{
+ MateHSVPrivate *priv;
+
+ g_return_val_if_fail (MATE_IS_HSV (hsv), FALSE);
+
+ priv = hsv->priv;
+
+ return priv->mode != DRAG_NONE;
+}
+
+static void
+mate_hsv_move (MateHSV *hsv,
+ GtkDirectionType dir)
+{
+ MateHSVPrivate *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;
+
+ mate_hsv_set_color (hsv, hue, sat, val);
+}
+