Color selection dialog rewrite.

Wed May 10 16:38:17 2000  Owen Taylor  <otaylor@redhat.com>

	* gtk/Makefile.am docs/Changes-1.4.txt gtk/gtkcolorsel.[ch]
	gtk/gtkhsv.[ch]: Color selection dialog rewrite.

	(Original triangle color selector from Simon Budig
	<Simon.Budig@unix-ag.org>, Cleaned up and rewritten for GTK+ by
	from Jonathan, Havoc, and Federico. Merge into GTK+ done by David
	Santiago <mrcooger@cyberverse.com>)

	* gtk/gtkcolorseldialog.[ch]: Split color selection dialog
	out into a separate widget.

	* gtk/testgtk.c: Add some checkbuttons for toggling palette
	and opacity controls.

Wed May 10 16:08:09 2000  Owen Taylor  <otaylor@redhat.com>

	* configure.in (GTK_LIBS_EXTRA): Remove references to gobject that
	snuck in prematurely.

1 files changed, 1407 insertions, 0 deletions

diff --git a/gtk/gtkhsv.c b/gtk/gtkhsv.c
new file mode 100644
index 000000000..568a14089
--- /dev/null
+++ b/gtk/gtkhsv.c
@@ -0,0 +1,1407 @@
+/* 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 Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <math.h>
+#include "gtksignal.h"
+#include "gtkhsv.h"
+
+
+
+/* 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 */
+typedef struct {
+	/* Color value */
+	double h;
+	double s;
+	double v;
+
+	/* Size and ring width */
+	int size;
+	int ring_width;
+
+	/* Window for capturing events */
+	GdkWindow *window;
+
+	/* GC for drawing */
+	GdkGC *gc;
+
+	/* Dragging mode */
+	DragMode mode;
+} HSVPrivate;
+
+
+
+/* Signal IDs */
+
+enum {
+	CHANGED,
+	LAST_SIGNAL
+};
+
+static void gtk_hsv_class_init (GtkHSVClass *class);
+static void gtk_hsv_init (GtkHSV *hsv);
+static void gtk_hsv_destroy (GtkObject *object);
+
+static void gtk_hsv_map (GtkWidget *widget);
+static void gtk_hsv_unmap (GtkWidget *widget);
+static void gtk_hsv_realize (GtkWidget *widget);
+static void gtk_hsv_unrealize (GtkWidget *widget);
+static void gtk_hsv_size_request (GtkWidget *widget, GtkRequisition *requisition);
+static void gtk_hsv_size_allocate (GtkWidget *widget, GtkAllocation *allocation);
+static gint gtk_hsv_button_press (GtkWidget *widget, GdkEventButton *event);
+static gint gtk_hsv_button_release (GtkWidget *widget, GdkEventButton *event);
+static gint gtk_hsv_motion (GtkWidget *widget, GdkEventMotion *event);
+static gint gtk_hsv_expose (GtkWidget *widget, GdkEventExpose *event);
+
+static guint hsv_signals[LAST_SIGNAL];
+
+static GtkWidgetClass *parent_class;
+
+
+
+/**
+ * gtk_hsv_get_type:
+ * @void:
+ *
+ * Registers the &GtkHSV class if necessary, and returns the type ID associated
+ * to it.
+ *
+ * Return value: The type ID of the &GtkHSV class.
+ **/
+GtkType
+gtk_hsv_get_type (void)
+{
+	static GtkType hsv_type = 0;
+
+	if (!hsv_type) {
+		static const GtkTypeInfo hsv_info = {
+			"GtkHSV",
+			sizeof (GtkHSV),
+			sizeof (GtkHSVClass),
+			(GtkClassInitFunc) gtk_hsv_class_init,
+			(GtkObjectInitFunc) gtk_hsv_init,
+			NULL, /* reserved_1 */
+			NULL, /* reserved_2 */
+			(GtkClassInitFunc) NULL
+		};
+
+		hsv_type = gtk_type_unique (gtk_widget_get_type (), &hsv_info);
+	}
+
+	return hsv_type;
+}
+
+/* Class initialization function for the HSV color selector */
+static void
+gtk_hsv_class_init (GtkHSVClass *class)
+{
+	GtkObjectClass *object_class;
+	GtkWidgetClass *widget_class;
+
+	object_class = (GtkObjectClass *) class;
+	widget_class = (GtkWidgetClass *) class;
+
+	parent_class = gtk_type_class (gtk_widget_get_type ());
+
+	hsv_signals[CHANGED] =
+		gtk_signal_new ("changed",
+				GTK_RUN_FIRST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (GtkHSVClass, changed),
+				gtk_marshal_NONE__NONE,
+				GTK_TYPE_NONE, 0);
+
+	gtk_object_class_add_signals (object_class, hsv_signals, LAST_SIGNAL);
+
+	object_class->destroy = gtk_hsv_destroy;
+
+	widget_class->map = gtk_hsv_map;
+	widget_class->unmap = gtk_hsv_unmap;
+	widget_class->realize = gtk_hsv_realize;
+	widget_class->unrealize = gtk_hsv_unrealize;
+	widget_class->size_request = gtk_hsv_size_request;
+	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->expose_event = gtk_hsv_expose;
+}
+
+/* Object initialization function for the HSV color selector */
+static void
+gtk_hsv_init (GtkHSV *hsv)
+{
+	HSVPrivate *priv;
+
+	priv = g_new0 (HSVPrivate, 1);
+	hsv->priv = priv;
+
+	GTK_WIDGET_SET_FLAGS (hsv, GTK_NO_WINDOW);
+
+	priv->h = 0.0;
+	priv->s = 0.0;
+	priv->v = 0.0;
+
+	priv->size = DEFAULT_SIZE;
+	priv->ring_width = DEFAULT_RING_WIDTH;
+}
+
+/* Destroy handler for the HSV color selector */
+static void
+gtk_hsv_destroy (GtkObject *object)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+
+	g_return_if_fail (object != NULL);
+	g_return_if_fail (GTK_IS_HSV (object));
+
+	hsv = GTK_HSV (object);
+	priv = hsv->priv;
+
+	g_free (priv);
+
+	if (GTK_OBJECT_CLASS (parent_class)->destroy)
+		(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
+}
+
+
+
+/* Default signal handlers */
+
+/* Map handler for the HSV color selector */
+static void
+gtk_hsv_map (GtkWidget *widget)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	if (GTK_WIDGET_MAPPED (widget))
+		return;
+
+	GTK_WIDGET_SET_FLAGS (widget, GTK_MAPPED);
+
+	gdk_window_show (priv->window);
+}
+
+/* Unmap handler for the HSV color selector */
+static void
+gtk_hsv_unmap (GtkWidget *widget)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	if (!GTK_WIDGET_MAPPED (widget))
+		return;
+
+	GTK_WIDGET_UNSET_FLAGS (widget, GTK_MAPPED);
+
+	gdk_window_hide (priv->window);
+}
+
+/* Realize handler for the HSV color selector */
+static void
+gtk_hsv_realize (GtkWidget *widget)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+	GdkWindowAttr attr;
+	int attr_mask;
+	GdkWindow *parent_window;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	GTK_WIDGET_SET_FLAGS (widget, GTK_REALIZED);
+
+	/* Create window */
+
+	attr.window_type = GDK_WINDOW_CHILD;
+	attr.x = widget->allocation.x;
+	attr.y = widget->allocation.y;
+	attr.width = widget->allocation.width;
+	attr.height = widget->allocation.height;
+	attr.wclass = GDK_INPUT_ONLY;
+	attr.event_mask = gtk_widget_get_events (widget);
+	attr.event_mask |= (GDK_BUTTON_PRESS_MASK
+			    | GDK_BUTTON_RELEASE_MASK
+			    | GDK_POINTER_MOTION_MASK);
+
+	attr_mask = GDK_WA_X | GDK_WA_Y;
+
+	parent_window = gtk_widget_get_parent_window (widget);
+
+	widget->window = parent_window;
+	gdk_window_ref (widget->window);
+
+	priv->window = gdk_window_new (parent_window, &attr, attr_mask);
+	gdk_window_set_user_data (priv->window, hsv);
+
+	widget->style = gtk_style_attach (widget->style, widget->window);
+
+	/* Create GC */
+
+	priv->gc = gdk_gc_new (parent_window);
+}
+
+/* Unrealize handler for the HSV color selector */
+static void
+gtk_hsv_unrealize (GtkWidget *widget)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	gdk_window_set_user_data (priv->window, NULL);
+	gdk_window_destroy (priv->window);
+	priv->window = NULL;
+
+	gdk_gc_unref (priv->gc);
+	priv->gc = NULL;
+
+	if (GTK_WIDGET_CLASS (parent_class)->unrealize)
+		(* GTK_WIDGET_CLASS (parent_class)->unrealize) (widget);
+}
+
+/* Size_request handler for the HSV color selector */
+static void
+gtk_hsv_size_request (GtkWidget *widget, GtkRequisition *requisition)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	requisition->width = priv->size;
+	requisition->height = priv->size;
+}
+
+/* Size_allocate handler for the HSV color selector */
+static void
+gtk_hsv_size_allocate (GtkWidget *widget, GtkAllocation *allocation)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	widget->allocation = *allocation;
+
+	if (GTK_WIDGET_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 (double *h, double *s, double *v)
+{
+	double hue, saturation, value;
+	double 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 ();
+		}
+	}
+}
+
+/* Converts from RGB to HSV */
+static void
+rgb_to_hsv (double *r, double *g, double *b)
+{
+	double red, green, blue;
+	double h, s, v;
+	double min, max;
+	double delta;
+
+	red = *r;
+	green = *g;
+	blue = *b;
+
+	h = 0.0;
+
+	if (red > green) {
+		if (red > blue)
+			max = red;
+		else
+			max = blue;
+
+		if (green < blue)
+			min = green;
+		else
+			min = blue;
+	} else {
+		if (green > blue)
+			max = green;
+		else
+			max = blue;
+
+		if (red < blue)
+			min = red;
+		else
+			min = blue;
+	}
+
+	v = max;
+
+	if (max != 0.0)
+		s = (max - min) / max;
+	else
+		s = 0.0;
+
+	if (s == 0.0)
+		h = 0.0;
+	else {
+		delta = max - min;
+
+		if (red == max)
+			h = (green - blue) / delta;
+		else if (green == max)
+			h = 2 + (blue - red) / delta;
+		else if (blue == max)
+			h = 4 + (red - green) / delta;
+
+		h /= 6.0;
+
+		if (h < 0.0)
+			h += 1.0;
+		else if (h > 1.0)
+			h -= 1.0;
+	}
+
+	*r = h;
+	*g = s;
+	*b = v;
+}
+
+/* Computes the vertices of the saturation/value triangle */
+static void
+compute_triangle (GtkHSV *hsv, int *hx, int *hy, int *sx, int *sy, int *vx, int *vy)
+{
+	HSVPrivate *priv;
+	double center;
+	double inner, outer;
+	double angle;
+
+	priv = hsv->priv;
+
+	center = priv->size / 2.0;
+	outer = priv->size / 2.0;
+	inner = outer - priv->ring_width;
+	angle = priv->h * 2.0 * M_PI;
+
+	*hx = floor (center + cos (angle) * inner + 0.5);
+	*hy = floor (center - sin (angle) * inner + 0.5);
+	*sx = floor (center + cos (angle + 2.0 * M_PI / 3.0) * inner + 0.5);
+	*sy = floor (center - sin (angle + 2.0 * M_PI / 3.0) * inner + 0.5);
+	*vx = floor (center + cos (angle + 4.0 * M_PI / 3.0) * inner + 0.5);
+	*vy = floor (center - sin (angle + 4.0 * M_PI / 3.0) * inner + 0.5);
+}
+
+/* Computes whether a point is inside the hue ring */
+static gboolean
+is_in_ring (GtkHSV *hsv, double x, double y)
+{
+	HSVPrivate *priv;
+	double dx, dy, dist;
+	double center, inner, outer;
+
+	priv = hsv->priv;
+
+	center = priv->size / 2.0;
+	outer = priv->size / 2.0;
+	inner = outer - priv->ring_width;
+
+	dx = x - center;
+	dy = center - 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, double x, double y, double *s, double *v)
+{
+	HSVPrivate *priv;
+	int ihx, ihy, isx, isy, ivx, ivy;
+	double hx, hy, sx, sy, vx, vy;
+	double center;
+
+	priv = hsv->priv;
+
+	compute_triangle (hsv, &ihx, &ihy, &isx, &isy, &ivx, &ivy);
+	center = priv->size / 2.0;
+	hx = ihx - center;
+	hy = center - ihy;
+	sx = isx - center;
+	sy = center - isy;
+	vx = ivx - center;
+	vy = center - ivy;
+	x -= center;
+	y = center - 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;
+
+			*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, double x, double 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, double x, double y)
+{
+	HSVPrivate *priv;
+	double center;
+	double dx, dy;
+	double angle;
+
+	priv = hsv->priv;
+
+	center = priv->size / 2.0;
+	dx = x - center;
+	dy = center - y;
+
+	angle = atan2 (dy, dx);
+	if (angle < 0.0)
+		angle += 2.0 * M_PI;
+
+	return angle / (2.0 * M_PI);
+}
+
+
+
+/* Event handlers */
+
+static void
+set_cross_grab (GtkHSV *hsv, guint32 time)
+{
+	HSVPrivate *priv;
+	GdkCursor *cursor;
+
+	priv = hsv->priv;
+
+	cursor = gdk_cursor_new (GDK_CROSSHAIR);
+	gdk_pointer_grab (priv->window, FALSE,
+			  (GDK_POINTER_MOTION_MASK
+			   | GDK_POINTER_MOTION_HINT_MASK
+			   | GDK_BUTTON_RELEASE_MASK),
+			  NULL,
+			  cursor,
+			  time);
+	gdk_cursor_destroy (cursor);
+
+}
+
+/* Button_press_event handler for the HSV color selector */
+static gint
+gtk_hsv_button_press (GtkWidget *widget, GdkEventButton *event)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+	double x, y;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	if (priv->mode != DRAG_NONE || event->button != 1)
+		return FALSE;
+
+	x = event->x;
+	y = event->y;
+
+	if (is_in_ring (hsv, x, y)) {
+		priv->mode = DRAG_H;
+		set_cross_grab (hsv, event->time);
+
+		gtk_hsv_set_color (hsv,
+				   compute_v (hsv, x, y),
+				   priv->s,
+				   priv->v);
+
+		return TRUE;
+	}
+
+	if (is_in_triangle (hsv, x, y)) {
+		double s, v;
+
+		priv->mode = DRAG_SV;
+		set_cross_grab (hsv, event->time);
+
+		compute_sv (hsv, x, y, &s, &v);
+		gtk_hsv_set_color (hsv, priv->h, s, v);
+		return TRUE;
+	}
+
+	return FALSE;
+}
+
+/* Button_release_event handler for the HSV color selector */
+static gint
+gtk_hsv_button_release (GtkWidget *widget, GdkEventButton *event)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+	DragMode mode;
+	double x, y;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	if (priv->mode == DRAG_NONE || event->button != 1)
+		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) {
+		double s, v;
+
+		compute_sv (hsv, x, y, &s, &v);
+		gtk_hsv_set_color (hsv, priv->h, s, v);
+	} else
+		g_assert_not_reached ();
+
+	gdk_pointer_ungrab (event->time);
+
+	return TRUE;
+}
+
+/* Motion_notify_event handler for the HSV color selector */
+static gint
+gtk_hsv_motion (GtkWidget *widget, GdkEventMotion *event)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+	double x, y;
+	gint ix, iy;
+	GdkModifierType mods;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	if (priv->mode == DRAG_NONE)
+		return FALSE;
+
+	if (event->is_hint) {
+		gdk_window_get_pointer (priv->window, &ix, &iy, &mods);
+		x = ix;
+		y = iy;
+	} else {
+		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) {
+		double 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, GdkDrawable *drawable, int x, int y, int width, int height)
+{
+	HSVPrivate *priv;
+	int xx, yy;
+	double dx, dy, dist;
+	double center;
+	double inner, outer;
+	guchar *buf, *p;
+	double angle;
+	double hue;
+	double r, g, b;
+	GdkBitmap *mask;
+	GdkGC *gc;
+	GdkColor color;
+
+	priv = hsv->priv;
+
+	center = priv->size / 2.0;
+
+	outer = priv->size / 2.0;
+	inner = outer - priv->ring_width;
+
+	/* Paint the ring */
+
+	buf = g_new (guchar, width * height * 3);
+
+	for (yy = 0; yy < height; yy++) {
+		p = buf + yy * width * 3;
+
+		dy = -(yy + y - center);
+
+		for (xx = 0; xx < width; xx++) {
+			dx = xx + x - center;
+
+			dist = dx * dx + dy * dy;
+			if (dist < (inner * inner) || dist > (outer * outer)) {
+				*p++ = 0;
+				*p++ = 0;
+				*p++ = 0;
+				continue;
+			}
+
+			angle = atan2 (dy, dx);
+			if (angle < 0.0)
+				angle += 2.0 * M_PI;
+
+			hue = angle / (2.0 * M_PI);
+
+			r = hue;
+			g = 1.0;
+			b = 1.0;
+			hsv_to_rgb (&r, &g, &b);
+
+			*p++ = floor (r * 255 + 0.5);
+			*p++ = floor (g * 255 + 0.5);
+			*p++ = floor (b * 255 + 0.5);
+		}
+	}
+
+	/* Create clipping mask */
+
+	mask = gdk_pixmap_new (NULL, width, height, 1);
+	gc = gdk_gc_new (mask);
+
+	color.pixel = 0;
+	gdk_gc_set_foreground (gc, &color);
+	gdk_draw_rectangle (mask, gc, TRUE,
+			    0, 0, width, height);
+
+
+	color.pixel = 1;
+	gdk_gc_set_foreground (gc, &color);
+	gdk_draw_arc (mask, gc, TRUE,
+		      -x, -y,
+		      priv->size - 1, priv->size - 1,
+		      0, 360 * 64);
+
+	color.pixel = 0;
+	gdk_gc_set_foreground (gc, &color);
+	gdk_draw_arc (mask, gc, TRUE,
+		      -x + priv->ring_width - 1, -y + priv->ring_width - 1,
+		      priv->size - 2 * priv->ring_width + 1, priv->size - 2 * priv->ring_width + 1,
+		      0, 360 * 64);
+
+	gdk_gc_unref (gc);
+
+	gdk_gc_set_clip_mask (priv->gc, mask);
+	gdk_gc_set_clip_origin (priv->gc, 0, 0);
+
+	/* Draw ring */
+
+	gdk_draw_rgb_image_dithalign (drawable, priv->gc, 0, 0, width, height,
+				      GDK_RGB_DITHER_MAX,
+				      buf,
+				      width * 3,
+				      x, y);
+
+	/* Draw value marker */
+
+	r = priv->h;
+	g = 1.0;
+	b = 1.0;
+	hsv_to_rgb (&r, &g, &b);
+
+	if (INTENSITY (r, g, b) > 0.5)
+		gdk_rgb_gc_set_foreground (priv->gc, 0x000000);
+	else
+		gdk_rgb_gc_set_foreground (priv->gc, 0xffffff);
+
+	gdk_draw_line (drawable, priv->gc,
+		       -x + center, -y + center,
+		       -x + center + cos (priv->h * 2.0 * M_PI) * center,
+		       -y + center - sin (priv->h * 2.0 * M_PI) * center);
+
+	gdk_gc_set_clip_mask (priv->gc, NULL);
+	gdk_bitmap_unref (mask);
+
+	g_free (buf);
+
+	/* Draw ring outline */
+
+	gdk_rgb_gc_set_foreground (priv->gc, 0x000000);
+
+	gdk_draw_arc (drawable, priv->gc, FALSE,
+		      -x, -y,
+		      priv->size - 1, priv->size - 1,
+		      0, 360 * 64);
+	gdk_draw_arc (drawable, priv->gc, FALSE,
+		      -x + priv->ring_width - 1, -y + priv->ring_width - 1,
+		      priv->size - 2 * priv->ring_width + 1, priv->size - 2 * priv->ring_width + 1,
+		      0, 360 * 64);
+}
+
+/* Converts an HSV triplet to an integer RGB triplet */
+static void
+get_color (double h, double s, double v, int *r, int *g, int *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))
+
+/* Paints the HSV triangle */
+static void
+paint_triangle (GtkHSV *hsv, GdkDrawable *drawable, int x, int y, int width, int height)
+{
+	HSVPrivate *priv;
+	int hx, hy, sx, sy, vx, vy; /* HSV vertices */
+	int x1, y1, r1, g1, b1; /* First vertex in scanline order */
+	int x2, y2, r2, g2, b2; /* Second vertex */
+	int x3, y3, r3, g3, b3; /* Third vertex */
+	int t;
+	guchar *buf, *p;
+	int xl, xr, rl, rr, gl, gr, bl, br; /* Scanline data */
+	int xx, yy;
+	GdkBitmap *mask;
+	GdkGC *gc;
+	GdkColor color;
+	GdkPoint points[3];
+	double r, g, b;
+
+	priv = hsv->priv;
+
+	/* 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 */
+
+	buf = g_new (guchar, width * height * 3);
+
+	for (yy = 0; yy < height; yy++) {
+		p = buf + yy * width * 3;
+
+		if (yy + y < y1 || yy + y > y3)
+			for (xx = 0; xx < width; xx++) {
+				*p++ = 0;
+				*p++ = 0;
+				*p++ = 0;
+			}
+		else {
+			if (yy + y < y2) {
+				xl = LERP (x1, x2, y1, y2, yy + y);
+
+				rl = LERP (r1, r2, y1, y2, yy + y);
+				gl = LERP (g1, g2, y1, y2, yy + y);
+				bl = LERP (b1, b2, y1, y2, yy + y);
+			} else {
+				xl = LERP (x2, x3, y2, y3, yy + y);
+
+				rl = LERP (r2, r3, y2, y3, yy + y);
+				gl = LERP (g2, g3, y2, y3, yy + y);
+				bl = LERP (b2, b3, y2, y3, yy + y);
+			}
+
+			xr = LERP (x1, x3, y1, y3, yy + y);
+
+			rr = LERP (r1, r3, y1, y3, yy + y);
+			gr = LERP (g1, g3, y1, y3, yy + y);
+			br = LERP (b1, b3, y1, y3, yy + y);
+
+			if (xl > xr) {
+				SWAP (xl, xr, t);
+				SWAP (rl, rr, t);
+				SWAP (gl, gr, t);
+				SWAP (bl, br, t);
+			}
+
+			for (xx = 0; xx < width; xx++) {
+				if (xx + x < xl || xx + x > xr) {
+					*p++ = 0;
+					*p++ = 0;
+					*p++ = 0;
+				} else {
+					*p++ = LERP (rl, rr, xl, xr, xx + x);
+					*p++ = LERP (gl, gr, xl, xr, xx + x);
+					*p++ = LERP (bl, br, xl, xr, xx + x);
+				}
+			}
+		}
+	}
+
+	/* Create clipping mask */
+
+	mask = gdk_pixmap_new (NULL, width, height, 1);
+	gc = gdk_gc_new (mask);
+
+	color.pixel = 0;
+	gdk_gc_set_foreground (gc, &color);
+	gdk_draw_rectangle (mask, gc, TRUE,
+			    0, 0, width, height);
+
+	color.pixel = 1;
+	gdk_gc_set_foreground (gc, &color);
+
+	points[0].x = x1 - x;
+	points[0].y = y1 - y;
+	points[1].x = x2 - x;
+	points[1].y = y2 - y;
+	points[2].x = x3 - x;
+	points[2].y = y3 - y;
+	gdk_draw_polygon (mask, gc, TRUE, points, 3);
+
+	gdk_gc_unref (gc);
+
+	gdk_gc_set_clip_mask (priv->gc, mask);
+	gdk_gc_set_clip_origin (priv->gc, 0, 0);
+
+	/* Draw triangle */
+
+	gdk_draw_rgb_image_dithalign (drawable, priv->gc, 0, 0, width, height,
+				      GDK_RGB_DITHER_MAX,
+				      buf,
+				      width * 3,
+				      x, y);
+
+	gdk_gc_set_clip_mask (priv->gc, NULL);
+	gdk_bitmap_unref (mask);
+
+	g_free (buf);
+
+	/* Draw triangle outline */
+
+	gdk_rgb_gc_set_foreground (priv->gc, 0x000000);
+
+	gdk_draw_polygon (drawable, priv->gc, FALSE, points, 3);
+
+	/* 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);
+
+	if (INTENSITY (r, g, b) > 0.5)
+		gdk_rgb_gc_set_foreground (priv->gc, 0x000000);
+	else
+		gdk_rgb_gc_set_foreground (priv->gc, 0xffffff);
+
+	gdk_draw_arc (drawable, priv->gc, FALSE,
+		      xx - 3, yy - 3,
+		      6, 6,
+		      0, 360 * 64);
+	gdk_draw_arc (drawable, priv->gc, FALSE,
+		      xx - 2, yy - 2,
+		      4, 4,
+		      0, 360 * 64);
+}
+
+/* Paints the contents of the HSV color selector */
+static void
+paint (GtkHSV *hsv, GdkDrawable *drawable, int x, int y, int width, int height)
+{
+	paint_ring (hsv, drawable, x, y, width, height);
+	paint_triangle (hsv, drawable, x, y, width, height);
+}
+
+/* Expose_event handler for the HSV color selector */
+static gint
+gtk_hsv_expose (GtkWidget *widget, GdkEventExpose *event)
+{
+	GtkHSV *hsv;
+	HSVPrivate *priv;
+	GdkRectangle rect, dest;
+	GdkPixmap *pixmap;
+
+	hsv = GTK_HSV (widget);
+	priv = hsv->priv;
+
+	if (!(GTK_WIDGET_DRAWABLE (widget) && event->window == widget->window))
+		return FALSE;
+
+	rect.x = widget->allocation.x;
+	rect.y = widget->allocation.y;
+	rect.width = widget->allocation.width;
+	rect.height = widget->allocation.height;
+
+	if (!gdk_rectangle_intersect (&event->area, &rect, &dest))
+		return FALSE;
+
+	pixmap = gdk_pixmap_new (widget->window, dest.width, dest.height,
+				 gtk_widget_get_visual (widget)->depth);
+
+	rect = dest;
+	rect.x = 0;
+	rect.y = 0;
+
+	gdk_draw_rectangle (pixmap,
+			    widget->style->bg_gc[GTK_WIDGET_STATE (widget)],
+			    TRUE,
+			    0, 0, dest.width, dest.height);
+	paint (hsv, pixmap,
+	       dest.x - widget->allocation.x, dest.y - widget->allocation.y,
+	       dest.width, dest.height);
+
+	gdk_draw_pixmap (widget->window,
+			 priv->gc,
+			 pixmap,
+			 0, 0,
+			 dest.x,
+			 dest.y,
+			 event->area.width, event->area.height);
+
+	gdk_pixmap_unref (pixmap);
+
+	return FALSE;
+}
+
+
+
+/**
+ * gtk_hsv_new:
+ * @void:
+ *
+ * Creates a new HSV color selector.
+ *
+ * Return value: A newly-created HSV color selector.
+ **/
+GtkWidget *
+gtk_hsv_new (void)
+{
+	return GTK_WIDGET (gtk_type_new (gtk_hsv_get_type ()));
+}
+
+/**
+ * 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.
+ **/
+void
+gtk_hsv_set_color (GtkHSV *hsv, double h, double s, double v)
+{
+	HSVPrivate *priv;
+
+	g_return_if_fail (hsv != NULL);
+	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;
+
+	gtk_signal_emit (GTK_OBJECT (hsv), hsv_signals[CHANGED]);
+
+	gtk_widget_queue_draw (GTK_WIDGET (hsv));
+}
+
+/**
+ * gtk_hsv_get_color:
+ * @hsv: An HSV color selector.
+ * @h: Return value for the hue.
+ * @s: Return value for the saturation.
+ * @v: 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
+gtk_hsv_get_color (GtkHSV *hsv, double *h, double *s, double *v)
+{
+	HSVPrivate *priv;
+
+	g_return_if_fail (hsv != NULL);
+	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.
+ **/
+void
+gtk_hsv_set_metrics (GtkHSV *hsv, int size, int ring_width)
+{
+	HSVPrivate *priv;
+	int same_size;
+
+	g_return_if_fail (hsv != NULL);
+	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: Return value for the diameter of the hue ring.
+ * @ring_width: Return value for the width of the hue ring.
+ *
+ * Queries the size and ring width of an HSV color selector.
+ **/
+void
+gtk_hsv_get_metrics (GtkHSV *hsv, int *size, int *ring_width)
+{
+	HSVPrivate *priv;
+
+	g_return_if_fail (hsv != NULL);
+	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:
+ *
+ * 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.
+ *
+ * Return value: 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
+gtk_hsv_is_adjusting (GtkHSV *hsv)
+{
+	HSVPrivate *priv;
+
+	g_return_val_if_fail (hsv != NULL, FALSE);
+	g_return_val_if_fail (GTK_IS_HSV (hsv), FALSE);
+
+	priv = hsv->priv;
+	return (priv->mode != DRAG_NONE);
+}
+
+/**
+ * gtk_hsv_to_rgb:
+ * @h: Hue.
+ * @s: Saturation.
+ * @v: Value.
+ * @r: Return value for the red component.
+ * @g: Return value for the green component.
+ * @b: Return value for the blue component.
+ * 
+ * Converts a color from HSV space to RGB.  Input values must be in the
+ * [0.0, 1.0] range; output values will be in the same range.
+ **/
+void
+gtk_hsv_to_rgb (double h, double s, double v, double *r, double *g, double *b)
+{
+	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);
+
+	hsv_to_rgb (&h, &s, &v);
+
+	if (r)
+		*r = h;
+
+	if (g)
+		*g = s;
+
+	if (b)
+		*b = v;
+}
+
+/**
+ * gtk_hsv_to_rgb:
+ * @r: Red.
+ * @g: Green.
+ * @b: Blue.
+ * @h: Return value for the hue component.
+ * @s: Return value for the saturation component.
+ * @v: Return value for the value component.
+ * 
+ * Converts a color from RGB space to HSV.  Input values must be in the
+ * [0.0, 1.0] range; output values will be in the same range.
+ **/
+void
+gtk_rgb_to_hsv (double r, double g, double b, double *h, double *s, double *v)
+{
+	g_return_if_fail (r >= 0.0 && r <= 1.0);
+	g_return_if_fail (g >= 0.0 && g <= 1.0);
+	g_return_if_fail (b >= 0.0 && b <= 1.0);
+
+	rgb_to_hsv (&r, &g, &b);
+
+	if (h)
+		*h = r;
+
+	if (s)
+		*s = g;
+
+	if (v)
+		*v = b;
+}