1 /* GTK - The GIMP Toolkit
2 * Copyright (C) 1997 David Mosberger
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the Free
16 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 #include "gtkdrawingarea.h"
25 #include "gtkradiobutton.h"
26 #include "gtksignal.h"
29 #define BOUNDS(a,x,y) (((a) < (x)) ? (x) : (((a) > (y)) ? (y) : (a)))
30 #define RADIUS 3 /* radius of the control points */
31 #define MIN_DISTANCE 8 /* min distance between control points */
33 #define GRAPH_MASK (GDK_EXPOSURE_MASK | \
34 GDK_POINTER_MOTION_MASK | \
35 GDK_POINTER_MOTION_HINT_MASK | \
36 GDK_ENTER_NOTIFY_MASK | \
37 GDK_BUTTON_PRESS_MASK | \
38 GDK_BUTTON_RELEASE_MASK | \
39 GDK_BUTTON1_MOTION_MASK)
41 static GtkDrawingAreaClass *parent_class = NULL;
42 static guint curve_type_changed_signal = 0;
45 /* forward declarations: */
46 static void gtk_curve_class_init (GtkCurveClass *class);
47 static void gtk_curve_init (GtkCurve *curve);
48 static void gtk_curve_finalize (GtkObject *object);
49 static gint gtk_curve_graph_events (GtkWidget *widget,
52 static void gtk_curve_size_graph (GtkCurve *curve);
55 gtk_curve_get_type (void)
57 static guint curve_type = 0;
61 GtkTypeInfo curve_info =
65 sizeof (GtkCurveClass),
66 (GtkClassInitFunc) gtk_curve_class_init,
67 (GtkObjectInitFunc) gtk_curve_init,
72 curve_type = gtk_type_unique (gtk_drawing_area_get_type (), &curve_info);
78 gtk_curve_class_init (GtkCurveClass *class)
80 GtkObjectClass *object_class;
82 parent_class = gtk_type_class (gtk_drawing_area_get_type ());
84 object_class = (GtkObjectClass *) class;
86 curve_type_changed_signal =
87 gtk_signal_new ("curve_type_changed", GTK_RUN_FIRST, object_class->type,
88 GTK_SIGNAL_OFFSET (GtkCurveClass, curve_type_changed),
89 gtk_signal_default_marshaller, GTK_TYPE_NONE, 0);
90 gtk_object_class_add_signals (object_class, &curve_type_changed_signal, 1);
92 object_class->finalize = gtk_curve_finalize;
96 gtk_curve_init (GtkCurve *curve)
100 curve->cursor_type = GDK_TOP_LEFT_ARROW;
101 curve->pixmap = NULL;
102 curve->curve_type = GTK_CURVE_TYPE_SPLINE;
104 curve->grab_point = -1;
106 curve->num_points = 0;
109 curve->num_ctlpoints = 0;
110 curve->ctlpoint = NULL;
117 old_mask = gtk_widget_get_events (GTK_WIDGET (curve));
118 gtk_widget_set_events (GTK_WIDGET (curve), old_mask | GRAPH_MASK);
119 gtk_signal_connect (GTK_OBJECT (curve), "event",
120 (GtkSignalFunc) gtk_curve_graph_events, curve);
121 gtk_curve_size_graph (curve);
125 project (gfloat value, gfloat min, gfloat max, int norm)
127 return (norm - 1) * ((value - min) / (max - min)) + 0.5;
131 unproject (gint value, gfloat min, gfloat max, int norm)
133 return value / (gfloat) (norm - 1) * (max - min) + min;
136 /* Solve the tridiagonal equation system that determines the second
137 derivatives for the interpolation points. (Based on Numerical
138 Recipies 2nd Edition.) */
140 spline_solve (int n, gfloat x[], gfloat y[], gfloat y2[])
145 u = g_malloc ((n - 1) * sizeof (u[0]));
147 y2[0] = u[0] = 0.0; /* set lower boundary condition to "natural" */
149 for (i = 1; i < n - 1; ++i)
151 sig = (x[i] - x[i - 1]) / (x[i + 1] - x[i - 1]);
152 p = sig * y2[i - 1] + 2.0;
153 y2[i] = (sig - 1.0) / p;
154 u[i] = ((y[i + 1] - y[i])
155 / (x[i + 1] - x[i]) - (y[i] - y[i - 1]) / (x[i] - x[i - 1]));
156 u[i] = (6.0 * u[i] / (x[i + 1] - x[i - 1]) - sig * u[i - 1]) / p;
160 for (k = n - 2; k >= 0; --k)
161 y2[k] = y2[k] * y2[k + 1] + u[k];
167 spline_eval (int n, gfloat x[], gfloat y[], gfloat y2[], gfloat val)
172 /* do a binary search for the right interval: */
173 k_lo = 0; k_hi = n - 1;
174 while (k_hi - k_lo > 1)
176 k = (k_hi + k_lo) / 2;
183 h = x[k_hi] - x[k_lo];
186 a = (x[k_hi] - val) / h;
187 b = (val - x[k_lo]) / h;
188 return a*y[k_lo] + b*y[k_hi] +
189 ((a*a*a - a)*y2[k_lo] + (b*b*b - b)*y2[k_hi]) * (h*h)/6.0;
193 gtk_curve_interpolate (GtkCurve *c, gint width, gint height)
198 vector = g_malloc (width * sizeof (vector[0]));
200 gtk_curve_get_vector (c, width, vector);
203 if (c->num_points != width)
205 c->num_points = width;
208 c->point = g_malloc (c->num_points * sizeof (c->point[0]));
211 for (i = 0; i < width; ++i)
213 c->point[i].x = RADIUS + i;
214 c->point[i].y = RADIUS + height
215 - project (vector[i], c->min_y, c->max_y, height);
220 gtk_curve_draw (GtkCurve *c, gint width, gint height)
229 if (c->height != height || c->num_points != width)
230 gtk_curve_interpolate (c, width, height);
232 state = GTK_STATE_NORMAL;
233 if (!GTK_WIDGET_IS_SENSITIVE (GTK_WIDGET (c)))
234 state = GTK_STATE_INSENSITIVE;
236 style = GTK_WIDGET (c)->style;
238 /* clear the pixmap: */
239 gdk_draw_rectangle (c->pixmap, style->bg_gc[state], TRUE,
240 0, 0, width + RADIUS * 2, height + RADIUS * 2);
242 /* draw the grid lines: (XXX make more meaningful) */
243 for (i = 0; i < 5; i++)
245 gdk_draw_line (c->pixmap, style->dark_gc[state],
246 RADIUS, i * (height / 4.0) + RADIUS,
247 width + RADIUS, i * (height / 4.0) + RADIUS);
248 gdk_draw_line (c->pixmap, style->dark_gc[state],
249 i * (width / 4.0) + RADIUS, RADIUS,
250 i * (width / 4.0) + RADIUS, height + RADIUS);
253 gdk_draw_points (c->pixmap, style->fg_gc[state], c->point, c->num_points);
254 if (c->curve_type != GTK_CURVE_TYPE_FREE)
255 for (i = 0; i < c->num_ctlpoints; ++i)
259 if (c->ctlpoint[i][0] < c->min_x)
262 x = project (c->ctlpoint[i][0], c->min_x, c->max_x,
265 project (c->ctlpoint[i][1], c->min_y, c->max_y,
269 gdk_draw_arc (c->pixmap, style->fg_gc[state], TRUE, x, y,
270 RADIUS * 2, RADIUS*2, 0, 360*64);
272 gdk_draw_pixmap (GTK_WIDGET (c)->window, style->fg_gc[state], c->pixmap,
273 0, 0, 0, 0, width + RADIUS * 2, height + RADIUS * 2);
277 gtk_curve_graph_events (GtkWidget *widget, GdkEvent *event, GtkCurve *c)
279 GdkCursorType new_type = c->cursor_type;
280 gint i, src, dst, leftbound, rightbound;
281 GdkEventButton *bevent;
282 GdkEventMotion *mevent;
285 gint cx, x, y, width, height;
286 gint closest_point = 0;
287 gfloat rx, ry, min_x;
292 width = w->allocation.width - RADIUS * 2;
293 height = w->allocation.height - RADIUS * 2;
295 /* get the pointer position */
296 gdk_window_get_pointer (w->window, &tx, &ty, NULL);
297 x = BOUNDS ((tx - RADIUS), 0, width);
298 y = BOUNDS ((ty - RADIUS), 0, height);
303 for (i = 0; i < c->num_ctlpoints; ++i)
305 cx = project (c->ctlpoint[i][0], min_x, c->max_x, width);
306 if ((guint) abs (x - cx) < distance)
308 distance = abs (x - cx);
317 gdk_pixmap_unref (c->pixmap);
322 c->pixmap = gdk_pixmap_new (w->window,
324 w->allocation.height, -1);
325 gtk_curve_draw (c, width, height);
328 case GDK_BUTTON_PRESS:
329 gtk_grab_add (widget);
331 bevent = (GdkEventButton *) event;
332 new_type = GDK_TCROSS;
334 switch (c->curve_type)
336 case GTK_CURVE_TYPE_LINEAR:
337 case GTK_CURVE_TYPE_SPLINE:
338 if (distance > MIN_DISTANCE)
340 /* insert a new control point */
341 if (c->num_ctlpoints > 0)
343 cx = project (c->ctlpoint[closest_point][0], min_x,
350 g_realloc (c->ctlpoint,
351 c->num_ctlpoints * sizeof (*c->ctlpoint));
352 for (i = c->num_ctlpoints - 1; i > closest_point; --i)
353 memcpy (c->ctlpoint + i, c->ctlpoint + i - 1,
354 sizeof (*c->ctlpoint));
356 c->grab_point = closest_point;
357 c->ctlpoint[c->grab_point][0] =
358 unproject (x, min_x, c->max_x, width);
359 c->ctlpoint[c->grab_point][1] =
360 unproject (height - y, c->min_y, c->max_y, height);
362 gtk_curve_interpolate (c, width, height);
365 case GTK_CURVE_TYPE_FREE:
366 c->point[x].x = RADIUS + x;
367 c->point[x].y = RADIUS + y;
372 gtk_curve_draw (c, width, height);
375 case GDK_BUTTON_RELEASE:
376 gtk_grab_remove (widget);
378 /* delete inactive points: */
379 if (c->curve_type != GTK_CURVE_TYPE_FREE)
381 for (src = dst = 0; src < c->num_ctlpoints; ++src)
383 if (c->ctlpoint[src][0] >= min_x)
385 memcpy (c->ctlpoint + dst, c->ctlpoint + src,
386 sizeof (*c->ctlpoint));
392 c->num_ctlpoints -= (src - dst);
393 if (c->num_ctlpoints <= 0)
395 c->num_ctlpoints = 1;
396 c->ctlpoint[0][0] = min_x;
397 c->ctlpoint[0][1] = c->min_y;
398 gtk_curve_interpolate (c, width, height);
399 gtk_curve_draw (c, width, height);
402 g_realloc (c->ctlpoint,
403 c->num_ctlpoints * sizeof (*c->ctlpoint));
406 new_type = GDK_FLEUR;
410 case GDK_MOTION_NOTIFY:
411 mevent = (GdkEventMotion *) event;
417 switch (c->curve_type)
419 case GTK_CURVE_TYPE_LINEAR:
420 case GTK_CURVE_TYPE_SPLINE:
421 if (c->grab_point == -1)
423 /* if no point is grabbed... */
424 if (distance <= MIN_DISTANCE)
425 new_type = GDK_FLEUR;
427 new_type = GDK_TCROSS;
431 /* drag the grabbed point */
432 new_type = GDK_TCROSS;
434 leftbound = -MIN_DISTANCE;
435 if (c->grab_point > 0)
436 leftbound = project (c->ctlpoint[c->grab_point - 1][0],
437 min_x, c->max_x, width);
439 rightbound = width + RADIUS * 2 + MIN_DISTANCE;
440 if (c->grab_point + 1 < c->num_ctlpoints)
441 rightbound = project (c->ctlpoint[c->grab_point + 1][0],
442 min_x, c->max_x, width);
444 if (tx <= leftbound || tx >= rightbound
445 || ty > height + RADIUS * 2 + MIN_DISTANCE
446 || ty < -MIN_DISTANCE)
447 c->ctlpoint[c->grab_point][0] = min_x - 1.0;
450 rx = unproject (x, min_x, c->max_x, width);
451 ry = unproject (height - y, c->min_y, c->max_y, height);
452 c->ctlpoint[c->grab_point][0] = rx;
453 c->ctlpoint[c->grab_point][1] = ry;
455 gtk_curve_interpolate (c, width, height);
456 gtk_curve_draw (c, width, height);
460 case GTK_CURVE_TYPE_FREE:
461 if (c->grab_point != -1)
463 if (c->grab_point > x)
479 for (i = x1; i <= x2; i++)
481 c->point[i].x = RADIUS + i;
482 c->point[i].y = RADIUS +
483 (y1 + ((y2 - y1) * (i - x1)) / (x2 - x1));
487 c->point[x].x = RADIUS + x;
488 c->point[x].y = RADIUS + y;
492 gtk_curve_draw (c, width, height);
494 if (mevent->state & GDK_BUTTON1_MASK)
495 new_type = GDK_TCROSS;
497 new_type = GDK_PENCIL;
500 if (new_type != (GdkCursorType) c->cursor_type)
504 c->cursor_type = new_type;
506 cursor = gdk_cursor_new (c->cursor_type);
507 gdk_window_set_cursor (w->window, cursor);
508 gdk_cursor_destroy (cursor);
519 gtk_curve_set_curve_type (GtkCurve *c, GtkCurveType new_type)
524 if (new_type != c->curve_type)
528 width = GTK_WIDGET(c)->allocation.width - RADIUS * 2;
529 height = GTK_WIDGET(c)->allocation.height - RADIUS * 2;
531 if (new_type == GTK_CURVE_TYPE_FREE)
533 gtk_curve_interpolate (c, width, height);
534 c->curve_type = new_type;
536 else if (c->curve_type == GTK_CURVE_TYPE_FREE)
539 g_free (c->ctlpoint);
540 c->num_ctlpoints = 9;
541 c->ctlpoint = g_malloc (c->num_ctlpoints * sizeof (*c->ctlpoint));
544 dx = (width - 1) / (gfloat) (c->num_ctlpoints - 1);
546 for (i = 0; i < c->num_ctlpoints; ++i, rx += dx)
548 x = (int) (rx + 0.5);
550 unproject (x, c->min_x, c->max_x, width);
552 unproject (RADIUS + height - c->point[x].y,
553 c->min_y, c->max_y, height);
555 c->curve_type = new_type;
556 gtk_curve_interpolate (c, width, height);
560 c->curve_type = new_type;
561 gtk_curve_interpolate (c, width, height);
563 gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal);
564 gtk_curve_draw (c, width, height);
569 gtk_curve_size_graph (GtkCurve *curve)
574 width = (curve->max_x - curve->min_x) + 1;
575 height = (curve->max_y - curve->min_y) + 1;
576 aspect = width / (gfloat) height;
577 if (width > gdk_screen_width () / 4)
578 width = gdk_screen_width () / 4;
579 if (height > gdk_screen_height () / 4)
580 height = gdk_screen_height () / 4;
583 width = height * aspect;
585 height = width / aspect;
587 gtk_drawing_area_size (GTK_DRAWING_AREA (curve),
588 width + RADIUS * 2, height + RADIUS * 2);
592 gtk_curve_reset_vector (GtkCurve *curve)
595 g_free (curve->ctlpoint);
597 curve->num_ctlpoints = 2;
598 curve->ctlpoint = g_malloc (2 * sizeof (curve->ctlpoint[0]));
599 curve->ctlpoint[0][0] = curve->min_x;
600 curve->ctlpoint[0][1] = curve->min_y;
601 curve->ctlpoint[1][0] = curve->max_x;
602 curve->ctlpoint[1][1] = curve->max_y;
608 width = GTK_WIDGET (curve)->allocation.width - RADIUS * 2;
609 height = GTK_WIDGET (curve)->allocation.height - RADIUS * 2;
611 if (curve->curve_type == GTK_CURVE_TYPE_FREE)
613 curve->curve_type = GTK_CURVE_TYPE_LINEAR;
614 gtk_curve_interpolate (curve, width, height);
615 curve->curve_type = GTK_CURVE_TYPE_FREE;
618 gtk_curve_interpolate (curve, width, height);
619 gtk_curve_draw (curve, width, height);
624 gtk_curve_reset (GtkCurve *c)
626 GtkCurveType old_type;
628 old_type = c->curve_type;
629 c->curve_type = GTK_CURVE_TYPE_SPLINE;
630 gtk_curve_reset_vector (c);
632 if (old_type != GTK_CURVE_TYPE_SPLINE)
633 gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal);
637 gtk_curve_set_gamma (GtkCurve *c, gfloat gamma)
639 gfloat x, one_over_gamma, height, one_over_width;
640 GtkCurveType old_type;
643 if (c->num_points < 2)
646 old_type = c->curve_type;
647 c->curve_type = GTK_CURVE_TYPE_FREE;
650 one_over_gamma = 1.0;
652 one_over_gamma = 1.0 / gamma;
653 one_over_width = 1.0 / (c->num_points - 1);
655 for (i = 0; i < c->num_points; ++i)
657 x = (gfloat) i / (c->num_points - 1);
658 c->point[i].x = RADIUS + i;
660 RADIUS + (height * (1.0 - pow (x, one_over_gamma)) + 0.5);
663 if (old_type != GTK_CURVE_TYPE_FREE)
664 gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal);
666 gtk_curve_draw (c, c->num_points, c->height);
670 gtk_curve_set_range (GtkCurve *curve,
671 gfloat min_x, gfloat max_x, gfloat min_y, gfloat max_y)
673 curve->min_x = min_x;
674 curve->max_x = max_x;
675 curve->min_y = min_y;
676 curve->max_y = max_y;
678 gtk_curve_size_graph (curve);
679 gtk_curve_reset_vector (curve);
683 gtk_curve_set_vector (GtkCurve *c, int veclen, gfloat vector[])
685 GtkCurveType old_type;
689 old_type = c->curve_type;
690 c->curve_type = GTK_CURVE_TYPE_FREE;
693 height = GTK_WIDGET (c)->allocation.height - RADIUS * 2;
696 height = (c->max_y - c->min_y);
697 if (height > gdk_screen_height () / 4)
698 height = gdk_screen_height () / 4;
701 c->num_points = veclen;
702 c->point = g_malloc (c->num_points * sizeof (c->point[0]));
705 dx = (veclen - 1.0) / (c->num_points - 1.0);
707 for (i = 0; i < c->num_points; ++i, rx += dx)
709 ry = vector[(int) (rx + 0.5)];
710 if (ry > c->max_y) ry = c->max_y;
711 if (ry < c->min_y) ry = c->min_y;
712 c->point[i].x = RADIUS + i;
714 RADIUS + height - project (ry, c->min_y, c->max_y, height);
716 if (old_type != GTK_CURVE_TYPE_FREE)
717 gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal);
719 gtk_curve_draw (c, c->num_points, height);
723 gtk_curve_get_vector (GtkCurve *c, int veclen, gfloat vector[])
725 gfloat rx, ry, dx, dy, min_x, delta_x, *mem, *xv, *yv, *y2v, prev;
726 gint dst, i, x, next, num_active_ctlpoints = 0, first_active = -1;
730 if (c->curve_type != GTK_CURVE_TYPE_FREE)
732 /* count active points: */
734 for (i = num_active_ctlpoints = 0; i < c->num_ctlpoints; ++i)
735 if (c->ctlpoint[i][0] > prev)
737 if (first_active < 0)
739 prev = c->ctlpoint[i][0];
740 ++num_active_ctlpoints;
743 /* handle degenerate case: */
744 if (num_active_ctlpoints < 2)
746 if (num_active_ctlpoints > 0)
747 ry = c->ctlpoint[first_active][1];
750 if (ry < c->min_y) ry = c->min_y;
751 if (ry > c->max_y) ry = c->max_y;
752 for (x = 0; x < veclen; ++x)
758 switch (c->curve_type)
760 case GTK_CURVE_TYPE_SPLINE:
761 mem = g_malloc (3 * num_active_ctlpoints * sizeof (gfloat));
763 yv = mem + num_active_ctlpoints;
764 y2v = mem + 2*num_active_ctlpoints;
767 for (i = dst = 0; i < c->num_ctlpoints; ++i)
768 if (c->ctlpoint[i][0] > prev)
770 prev = c->ctlpoint[i][0];
771 xv[dst] = c->ctlpoint[i][0];
772 yv[dst] = c->ctlpoint[i][1];
776 spline_solve (num_active_ctlpoints, xv, yv, y2v);
779 dx = (c->max_x - min_x) / (veclen - 1);
780 for (x = 0; x < veclen; ++x, rx += dx)
782 ry = spline_eval (num_active_ctlpoints, xv, yv, y2v, rx);
783 if (ry < c->min_y) ry = c->min_y;
784 if (ry > c->max_y) ry = c->max_y;
791 case GTK_CURVE_TYPE_LINEAR:
792 dx = (c->max_x - min_x) / (veclen - 1);
797 for (x = 0; x < veclen; ++x, rx += dx)
799 if (rx >= c->ctlpoint[i][0])
801 if (rx > c->ctlpoint[i][0])
805 while (next < c->num_ctlpoints
806 && c->ctlpoint[next][0] <= c->ctlpoint[i][0])
808 if (next < c->num_ctlpoints)
810 delta_x = c->ctlpoint[next][0] - c->ctlpoint[i][0];
811 dy = ((c->ctlpoint[next][1] - c->ctlpoint[i][1])
814 ry = c->ctlpoint[i][1];
823 case GTK_CURVE_TYPE_FREE:
827 dx = c->num_points / (double) veclen;
828 for (x = 0; x < veclen; ++x, rx += dx)
829 vector[x] = unproject (RADIUS + c->height - c->point[(int) rx].y,
834 memset (vector, 0, veclen * sizeof (vector[0]));
842 return gtk_type_new (gtk_curve_get_type ());
846 gtk_curve_finalize (GtkObject *object)
850 g_return_if_fail (object != NULL);
851 g_return_if_fail (GTK_IS_CURVE (object));
853 curve = GTK_CURVE (object);
855 gdk_pixmap_unref (curve->pixmap);
857 g_free (curve->point);
859 g_free (curve->ctlpoint);
861 (*GTK_OBJECT_CLASS (parent_class)->finalize) (object);