/* GTK - The GIMP Toolkit * Copyright (C) 1997 David Mosberger * * 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, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ /* * 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 #include #include #include "gtkcurve.h" #include "gtkdrawingarea.h" #include "gtkmain.h" #include "gtkradiobutton.h" #include "gtksignal.h" #include "gtktable.h" #include "gtkintl.h" #define RADIUS 3 /* radius of the control points */ #define MIN_DISTANCE 8 /* min distance between control points */ #define GRAPH_MASK (GDK_EXPOSURE_MASK | \ GDK_POINTER_MOTION_MASK | \ GDK_POINTER_MOTION_HINT_MASK | \ GDK_ENTER_NOTIFY_MASK | \ GDK_BUTTON_PRESS_MASK | \ GDK_BUTTON_RELEASE_MASK | \ GDK_BUTTON1_MOTION_MASK) enum { PROP_0, PROP_CURVE_TYPE, PROP_MIN_X, PROP_MAX_X, PROP_MIN_Y, PROP_MAX_Y }; static GtkDrawingAreaClass *parent_class = NULL; static guint curve_type_changed_signal = 0; /* forward declarations: */ static void gtk_curve_class_init (GtkCurveClass *class); static void gtk_curve_init (GtkCurve *curve); static void gtk_curve_get_property (GObject *object, guint param_id, GValue *value, GParamSpec *pspec); static void gtk_curve_set_property (GObject *object, guint param_id, const GValue *value, GParamSpec *pspec); static void gtk_curve_finalize (GObject *object); static gint gtk_curve_graph_events (GtkWidget *widget, GdkEvent *event, GtkCurve *c); static void gtk_curve_size_graph (GtkCurve *curve); GtkType gtk_curve_get_type (void) { static GtkType curve_type = 0; if (!curve_type) { static const GtkTypeInfo curve_info = { "GtkCurve", sizeof (GtkCurve), sizeof (GtkCurveClass), (GtkClassInitFunc) gtk_curve_class_init, (GtkObjectInitFunc) gtk_curve_init, /* reserved_1 */ NULL, /* reserved_2 */ NULL, (GtkClassInitFunc) NULL, }; curve_type = gtk_type_unique (GTK_TYPE_DRAWING_AREA, &curve_info); } return curve_type; } static void gtk_curve_class_init (GtkCurveClass *class) { GObjectClass *gobject_class = G_OBJECT_CLASS (class); GtkObjectClass *object_class = GTK_OBJECT_CLASS (class); parent_class = gtk_type_class (GTK_TYPE_DRAWING_AREA); gobject_class->finalize = gtk_curve_finalize; gobject_class->set_property = gtk_curve_set_property; gobject_class->get_property = gtk_curve_get_property; g_object_class_install_property (gobject_class, PROP_CURVE_TYPE, g_param_spec_enum ("curve_type", _("Curve type"), _("Is this curve linear, spline interpolated, or free-form"), GTK_TYPE_CURVE_TYPE, GTK_CURVE_TYPE_LINEAR, G_PARAM_READABLE | G_PARAM_WRITABLE)); g_object_class_install_property (gobject_class, PROP_MIN_X, g_param_spec_float ("min_x", _("Minimum X"), _("Minimum possible value for X"), -G_MAXFLOAT, G_MAXFLOAT, 0.0, G_PARAM_READABLE | G_PARAM_WRITABLE)); g_object_class_install_property (gobject_class, PROP_MAX_X, g_param_spec_float ("max_x", _("Maximum X"), _("Maximum possible X value."), -G_MAXFLOAT, G_MAXFLOAT, 1.0, G_PARAM_READABLE | G_PARAM_WRITABLE)); g_object_class_install_property (gobject_class, PROP_MIN_Y, g_param_spec_float ("min_y", _("Minimum Y"), _("Minimum possible value for Y"), -G_MAXFLOAT, G_MAXFLOAT, 0.0, G_PARAM_READABLE | G_PARAM_WRITABLE)); g_object_class_install_property (gobject_class, PROP_MAX_Y, g_param_spec_float ("max_y", _("Maximum Y"), _("Maximum possible value for Y"), -G_MAXFLOAT, G_MAXFLOAT, 1.0, G_PARAM_READABLE | G_PARAM_WRITABLE)); curve_type_changed_signal = gtk_signal_new ("curve_type_changed", GTK_RUN_FIRST, GTK_CLASS_TYPE (object_class), GTK_SIGNAL_OFFSET (GtkCurveClass, curve_type_changed), gtk_marshal_VOID__VOID, GTK_TYPE_NONE, 0); } static void gtk_curve_init (GtkCurve *curve) { gint old_mask; curve->cursor_type = GDK_TOP_LEFT_ARROW; curve->pixmap = NULL; curve->curve_type = GTK_CURVE_TYPE_SPLINE; curve->height = 0; curve->grab_point = -1; curve->num_points = 0; curve->point = 0; curve->num_ctlpoints = 0; curve->ctlpoint = NULL; curve->min_x = 0.0; curve->max_x = 1.0; curve->min_y = 0.0; curve->max_y = 1.0; old_mask = gtk_widget_get_events (GTK_WIDGET (curve)); gtk_widget_set_events (GTK_WIDGET (curve), old_mask | GRAPH_MASK); gtk_signal_connect (GTK_OBJECT (curve), "event", (GtkSignalFunc) gtk_curve_graph_events, curve); gtk_curve_size_graph (curve); } static void gtk_curve_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec) { GtkCurve *curve = GTK_CURVE (object); switch (prop_id) { case PROP_CURVE_TYPE: gtk_curve_set_curve_type (curve, g_value_get_enum (value)); break; case PROP_MIN_X: gtk_curve_set_range (curve, g_value_get_float (value), curve->max_x, curve->min_y, curve->max_y); break; case PROP_MAX_X: gtk_curve_set_range (curve, curve->min_x, g_value_get_float (value), curve->min_y, curve->max_y); break; case PROP_MIN_Y: gtk_curve_set_range (curve, curve->min_x, curve->max_x, g_value_get_float (value), curve->max_y); break; case PROP_MAX_Y: gtk_curve_set_range (curve, curve->min_x, curve->max_x, curve->min_y, g_value_get_float (value)); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gtk_curve_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec) { GtkCurve *curve = GTK_CURVE (object); switch (prop_id) { case PROP_CURVE_TYPE: g_value_set_enum (value, curve->curve_type); break; case PROP_MIN_X: g_value_set_float (value, curve->min_x); break; case PROP_MAX_X: g_value_set_float (value, curve->max_x); break; case PROP_MIN_Y: g_value_set_float (value, curve->min_y); break; case PROP_MAX_Y: g_value_set_float (value, curve->max_y); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static int project (gfloat value, gfloat min, gfloat max, int norm) { return (norm - 1) * ((value - min) / (max - min)) + 0.5; } static gfloat unproject (gint value, gfloat min, gfloat max, int norm) { return value / (gfloat) (norm - 1) * (max - min) + min; } /* Solve the tridiagonal equation system that determines the second derivatives for the interpolation points. (Based on Numerical Recipies 2nd Edition.) */ static void spline_solve (int n, gfloat x[], gfloat y[], gfloat y2[]) { gfloat p, sig, *u; gint i, k; u = g_malloc ((n - 1) * sizeof (u[0])); y2[0] = u[0] = 0.0; /* set lower boundary condition to "natural" */ for (i = 1; i < n - 1; ++i) { sig = (x[i] - x[i - 1]) / (x[i + 1] - x[i - 1]); p = sig * y2[i - 1] + 2.0; y2[i] = (sig - 1.0) / p; u[i] = ((y[i + 1] - y[i]) / (x[i + 1] - x[i]) - (y[i] - y[i - 1]) / (x[i] - x[i - 1])); u[i] = (6.0 * u[i] / (x[i + 1] - x[i - 1]) - sig * u[i - 1]) / p; } y2[n - 1] = 0.0; for (k = n - 2; k >= 0; --k) y2[k] = y2[k] * y2[k + 1] + u[k]; g_free (u); } static gfloat spline_eval (int n, gfloat x[], gfloat y[], gfloat y2[], gfloat val) { gint k_lo, k_hi, k; gfloat h, b, a; /* do a binary search for the right interval: */ k_lo = 0; k_hi = n - 1; while (k_hi - k_lo > 1) { k = (k_hi + k_lo) / 2; if (x[k] > val) k_hi = k; else k_lo = k; } h = x[k_hi] - x[k_lo]; g_assert (h > 0.0); a = (x[k_hi] - val) / h; b = (val - x[k_lo]) / h; return a*y[k_lo] + b*y[k_hi] + ((a*a*a - a)*y2[k_lo] + (b*b*b - b)*y2[k_hi]) * (h*h)/6.0; } static void gtk_curve_interpolate (GtkCurve *c, gint width, gint height) { gfloat *vector; int i; vector = g_malloc (width * sizeof (vector[0])); gtk_curve_get_vector (c, width, vector); c->height = height; if (c->num_points != width) { c->num_points = width; if (c->point) g_free (c->point); c->point = g_malloc (c->num_points * sizeof (c->point[0])); } for (i = 0; i < width; ++i) { c->point[i].x = RADIUS + i; c->point[i].y = RADIUS + height - project (vector[i], c->min_y, c->max_y, height); } g_free (vector); } static void gtk_curve_draw (GtkCurve *c, gint width, gint height) { GtkStateType state; GtkStyle *style; gint i; if (!c->pixmap) return; if (c->height != height || c->num_points != width) gtk_curve_interpolate (c, width, height); state = GTK_STATE_NORMAL; if (!GTK_WIDGET_IS_SENSITIVE (GTK_WIDGET (c))) state = GTK_STATE_INSENSITIVE; style = GTK_WIDGET (c)->style; /* clear the pixmap: */ gtk_paint_flat_box (style, c->pixmap, GTK_STATE_NORMAL, GTK_SHADOW_NONE, NULL, GTK_WIDGET(c), "curve_bg", 0, 0, width + RADIUS * 2, height + RADIUS * 2); /* draw the grid lines: (XXX make more meaningful) */ for (i = 0; i < 5; i++) { gdk_draw_line (c->pixmap, style->dark_gc[state], RADIUS, i * (height / 4.0) + RADIUS, width + RADIUS, i * (height / 4.0) + RADIUS); gdk_draw_line (c->pixmap, style->dark_gc[state], i * (width / 4.0) + RADIUS, RADIUS, i * (width / 4.0) + RADIUS, height + RADIUS); } gdk_draw_points (c->pixmap, style->fg_gc[state], c->point, c->num_points); if (c->curve_type != GTK_CURVE_TYPE_FREE) for (i = 0; i < c->num_ctlpoints; ++i) { gint x, y; if (c->ctlpoint[i][0] < c->min_x) continue; x = project (c->ctlpoint[i][0], c->min_x, c->max_x, width); y = height - project (c->ctlpoint[i][1], c->min_y, c->max_y, height); /* draw a bullet: */ gdk_draw_arc (c->pixmap, style->fg_gc[state], TRUE, x, y, RADIUS * 2, RADIUS*2, 0, 360*64); } gdk_draw_pixmap (GTK_WIDGET (c)->window, style->fg_gc[state], c->pixmap, 0, 0, 0, 0, width + RADIUS * 2, height + RADIUS * 2); } static gint gtk_curve_graph_events (GtkWidget *widget, GdkEvent *event, GtkCurve *c) { GdkCursorType new_type = c->cursor_type; gint i, src, dst, leftbound, rightbound; GdkEventButton *bevent; GdkEventMotion *mevent; GtkWidget *w; gint tx, ty; gint cx, x, y, width, height; gint closest_point = 0; gfloat rx, ry, min_x; guint distance; gint x1, x2, y1, y2; w = GTK_WIDGET (c); width = w->allocation.width - RADIUS * 2; height = w->allocation.height - RADIUS * 2; if ((width < 0) || (height < 0)) return FALSE; /* get the pointer position */ gdk_window_get_pointer (w->window, &tx, &ty, NULL); x = CLAMP ((tx - RADIUS), 0, width-1); y = CLAMP ((ty - RADIUS), 0, height-1); min_x = c->min_x; distance = ~0U; for (i = 0; i < c->num_ctlpoints; ++i) { cx = project (c->ctlpoint[i][0], min_x, c->max_x, width); if ((guint) abs (x - cx) < distance) { distance = abs (x - cx); closest_point = i; } } switch (event->type) { case GDK_CONFIGURE: if (c->pixmap) gdk_pixmap_unref (c->pixmap); c->pixmap = 0; /* fall through */ case GDK_EXPOSE: if (!c->pixmap) c->pixmap = gdk_pixmap_new (w->window, w->allocation.width, w->allocation.height, -1); gtk_curve_draw (c, width, height); break; case GDK_BUTTON_PRESS: gtk_grab_add (widget); bevent = (GdkEventButton *) event; new_type = GDK_TCROSS; switch (c->curve_type) { case GTK_CURVE_TYPE_LINEAR: case GTK_CURVE_TYPE_SPLINE: if (distance > MIN_DISTANCE) { /* insert a new control point */ if (c->num_ctlpoints > 0) { cx = project (c->ctlpoint[closest_point][0], min_x, c->max_x, width); if (x > cx) ++closest_point; } ++c->num_ctlpoints; c->ctlpoint = g_realloc (c->ctlpoint, c->num_ctlpoints * sizeof (*c->ctlpoint)); for (i = c->num_ctlpoints - 1; i > closest_point; --i) memcpy (c->ctlpoint + i, c->ctlpoint + i - 1, sizeof (*c->ctlpoint)); } c->grab_point = closest_point; c->ctlpoint[c->grab_point][0] = unproject (x, min_x, c->max_x, width); c->ctlpoint[c->grab_point][1] = unproject (height - y, c->min_y, c->max_y, height); gtk_curve_interpolate (c, width, height); break; case GTK_CURVE_TYPE_FREE: c->point[x].x = RADIUS + x; c->point[x].y = RADIUS + y; c->grab_point = x; c->last = y; break; } gtk_curve_draw (c, width, height); break; case GDK_BUTTON_RELEASE: gtk_grab_remove (widget); /* delete inactive points: */ if (c->curve_type != GTK_CURVE_TYPE_FREE) { for (src = dst = 0; src < c->num_ctlpoints; ++src) { if (c->ctlpoint[src][0] >= min_x) { memcpy (c->ctlpoint + dst, c->ctlpoint + src, sizeof (*c->ctlpoint)); ++dst; } } if (dst < src) { c->num_ctlpoints -= (src - dst); if (c->num_ctlpoints <= 0) { c->num_ctlpoints = 1; c->ctlpoint[0][0] = min_x; c->ctlpoint[0][1] = c->min_y; gtk_curve_interpolate (c, width, height); gtk_curve_draw (c, width, height); } c->ctlpoint = g_realloc (c->ctlpoint, c->num_ctlpoints * sizeof (*c->ctlpoint)); } } new_type = GDK_FLEUR; c->grab_point = -1; break; case GDK_MOTION_NOTIFY: mevent = (GdkEventMotion *) event; switch (c->curve_type) { case GTK_CURVE_TYPE_LINEAR: case GTK_CURVE_TYPE_SPLINE: if (c->grab_point == -1) { /* if no point is grabbed... */ if (distance <= MIN_DISTANCE) new_type = GDK_FLEUR; else new_type = GDK_TCROSS; } else { /* drag the grabbed point */ new_type = GDK_TCROSS; leftbound = -MIN_DISTANCE; if (c->grab_point > 0) leftbound = project (c->ctlpoint[c->grab_point - 1][0], min_x, c->max_x, width); rightbound = width + RADIUS * 2 + MIN_DISTANCE; if (c->grab_point + 1 < c->num_ctlpoints) rightbound = project (c->ctlpoint[c->grab_point + 1][0], min_x, c->max_x, width); if (tx <= leftbound || tx >= rightbound || ty > height + RADIUS * 2 + MIN_DISTANCE || ty < -MIN_DISTANCE) c->ctlpoint[c->grab_point][0] = min_x - 1.0; else { rx = unproject (x, min_x, c->max_x, width); ry = unproject (height - y, c->min_y, c->max_y, height); c->ctlpoint[c->grab_point][0] = rx; c->ctlpoint[c->grab_point][1] = ry; } gtk_curve_interpolate (c, width, height); gtk_curve_draw (c, width, height); } break; case GTK_CURVE_TYPE_FREE: if (c->grab_point != -1) { if (c->grab_point > x) { x1 = x; x2 = c->grab_point; y1 = y; y2 = c->last; } else { x1 = c->grab_point; x2 = x; y1 = c->last; y2 = y; } if (x2 != x1) for (i = x1; i <= x2; i++) { c->point[i].x = RADIUS + i; c->point[i].y = RADIUS + (y1 + ((y2 - y1) * (i - x1)) / (x2 - x1)); } else { c->point[x].x = RADIUS + x; c->point[x].y = RADIUS + y; } c->grab_point = x; c->last = y; gtk_curve_draw (c, width, height); } if (mevent->state & GDK_BUTTON1_MASK) new_type = GDK_TCROSS; else new_type = GDK_PENCIL; break; } if (new_type != (GdkCursorType) c->cursor_type) { GdkCursor *cursor; c->cursor_type = new_type; cursor = gdk_cursor_new (c->cursor_type); gdk_window_set_cursor (w->window, cursor); gdk_cursor_destroy (cursor); } break; default: break; } return FALSE; } void gtk_curve_set_curve_type (GtkCurve *c, GtkCurveType new_type) { gfloat rx, dx; gint x, i; if (new_type != c->curve_type) { gint width, height; width = GTK_WIDGET(c)->allocation.width - RADIUS * 2; height = GTK_WIDGET(c)->allocation.height - RADIUS * 2; if (new_type == GTK_CURVE_TYPE_FREE) { gtk_curve_interpolate (c, width, height); c->curve_type = new_type; } else if (c->curve_type == GTK_CURVE_TYPE_FREE) { if (c->ctlpoint) g_free (c->ctlpoint); c->num_ctlpoints = 9; c->ctlpoint = g_malloc (c->num_ctlpoints * sizeof (*c->ctlpoint)); rx = 0.0; dx = (width - 1) / (gfloat) (c->num_ctlpoints - 1); for (i = 0; i < c->num_ctlpoints; ++i, rx += dx) { x = (int) (rx + 0.5); c->ctlpoint[i][0] = unproject (x, c->min_x, c->max_x, width); c->ctlpoint[i][1] = unproject (RADIUS + height - c->point[x].y, c->min_y, c->max_y, height); } c->curve_type = new_type; gtk_curve_interpolate (c, width, height); } else { c->curve_type = new_type; gtk_curve_interpolate (c, width, height); } gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal); g_object_notify (G_OBJECT (c), "curve_type"); gtk_curve_draw (c, width, height); } } static void gtk_curve_size_graph (GtkCurve *curve) { gint width, height; gfloat aspect; width = (curve->max_x - curve->min_x) + 1; height = (curve->max_y - curve->min_y) + 1; aspect = width / (gfloat) height; if (width > gdk_screen_width () / 4) width = gdk_screen_width () / 4; if (height > gdk_screen_height () / 4) height = gdk_screen_height () / 4; if (aspect < 1.0) width = height * aspect; else height = width / aspect; gtk_drawing_area_size (GTK_DRAWING_AREA (curve), width + RADIUS * 2, height + RADIUS * 2); } static void gtk_curve_reset_vector (GtkCurve *curve) { if (curve->ctlpoint) g_free (curve->ctlpoint); curve->num_ctlpoints = 2; curve->ctlpoint = g_malloc (2 * sizeof (curve->ctlpoint[0])); curve->ctlpoint[0][0] = curve->min_x; curve->ctlpoint[0][1] = curve->min_y; curve->ctlpoint[1][0] = curve->max_x; curve->ctlpoint[1][1] = curve->max_y; if (curve->pixmap) { gint width, height; width = GTK_WIDGET (curve)->allocation.width - RADIUS * 2; height = GTK_WIDGET (curve)->allocation.height - RADIUS * 2; if (curve->curve_type == GTK_CURVE_TYPE_FREE) { curve->curve_type = GTK_CURVE_TYPE_LINEAR; gtk_curve_interpolate (curve, width, height); curve->curve_type = GTK_CURVE_TYPE_FREE; } else gtk_curve_interpolate (curve, width, height); gtk_curve_draw (curve, width, height); } } void gtk_curve_reset (GtkCurve *c) { GtkCurveType old_type; old_type = c->curve_type; c->curve_type = GTK_CURVE_TYPE_SPLINE; gtk_curve_reset_vector (c); if (old_type != GTK_CURVE_TYPE_SPLINE) gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal); } void gtk_curve_set_gamma (GtkCurve *c, gfloat gamma) { gfloat x, one_over_gamma, height, one_over_width; GtkCurveType old_type; gint i; if (c->num_points < 2) return; old_type = c->curve_type; c->curve_type = GTK_CURVE_TYPE_FREE; if (gamma <= 0) one_over_gamma = 1.0; else one_over_gamma = 1.0 / gamma; one_over_width = 1.0 / (c->num_points - 1); height = c->height; for (i = 0; i < c->num_points; ++i) { x = (gfloat) i / (c->num_points - 1); c->point[i].x = RADIUS + i; c->point[i].y = RADIUS + (height * (1.0 - pow (x, one_over_gamma)) + 0.5); } if (old_type != GTK_CURVE_TYPE_FREE) gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal); gtk_curve_draw (c, c->num_points, c->height); } void gtk_curve_set_range (GtkCurve *curve, gfloat min_x, gfloat max_x, gfloat min_y, gfloat max_y) { if (curve->min_x != min_x) { curve->min_x = min_x; g_object_notify (G_OBJECT (curve), "min_x"); } if (curve->max_x != max_x) { curve->max_x = max_x; g_object_notify (G_OBJECT (curve), "max_x"); } if (curve->min_y != min_y) { curve->min_y = min_y; g_object_notify (G_OBJECT (curve), "min_y"); } if (curve->max_y != max_y) { curve->max_y = max_y; g_object_notify (G_OBJECT (curve), "max_y"); } gtk_curve_size_graph (curve); gtk_curve_reset_vector (curve); } void gtk_curve_set_vector (GtkCurve *c, int veclen, gfloat vector[]) { GtkCurveType old_type; gfloat rx, dx, ry; gint i, height; old_type = c->curve_type; c->curve_type = GTK_CURVE_TYPE_FREE; if (c->point) height = GTK_WIDGET (c)->allocation.height - RADIUS * 2; else { height = (c->max_y - c->min_y); if (height > gdk_screen_height () / 4) height = gdk_screen_height () / 4; c->height = height; c->num_points = veclen; c->point = g_malloc (c->num_points * sizeof (c->point[0])); } rx = 0; dx = (veclen - 1.0) / (c->num_points - 1.0); for (i = 0; i < c->num_points; ++i, rx += dx) { ry = vector[(int) (rx + 0.5)]; if (ry > c->max_y) ry = c->max_y; if (ry < c->min_y) ry = c->min_y; c->point[i].x = RADIUS + i; c->point[i].y = RADIUS + height - project (ry, c->min_y, c->max_y, height); } if (old_type != GTK_CURVE_TYPE_FREE) gtk_signal_emit (GTK_OBJECT (c), curve_type_changed_signal); gtk_curve_draw (c, c->num_points, height); } void gtk_curve_get_vector (GtkCurve *c, int veclen, gfloat vector[]) { gfloat rx, ry, dx, dy, min_x, delta_x, *mem, *xv, *yv, *y2v, prev; gint dst, i, x, next, num_active_ctlpoints = 0, first_active = -1; min_x = c->min_x; if (c->curve_type != GTK_CURVE_TYPE_FREE) { /* count active points: */ prev = min_x - 1.0; for (i = num_active_ctlpoints = 0; i < c->num_ctlpoints; ++i) if (c->ctlpoint[i][0] > prev) { if (first_active < 0) first_active = i; prev = c->ctlpoint[i][0]; ++num_active_ctlpoints; } /* handle degenerate case: */ if (num_active_ctlpoints < 2) { if (num_active_ctlpoints > 0) ry = c->ctlpoint[first_active][1]; else ry = c->min_y; if (ry < c->min_y) ry = c->min_y; if (ry > c->max_y) ry = c->max_y; for (x = 0; x < veclen; ++x) vector[x] = ry; return; } } switch (c->curve_type) { case GTK_CURVE_TYPE_SPLINE: mem = g_malloc (3 * num_active_ctlpoints * sizeof (gfloat)); xv = mem; yv = mem + num_active_ctlpoints; y2v = mem + 2*num_active_ctlpoints; prev = min_x - 1.0; for (i = dst = 0; i < c->num_ctlpoints; ++i) if (c->ctlpoint[i][0] > prev) { prev = c->ctlpoint[i][0]; xv[dst] = c->ctlpoint[i][0]; yv[dst] = c->ctlpoint[i][1]; ++dst; } spline_solve (num_active_ctlpoints, xv, yv, y2v); rx = min_x; dx = (c->max_x - min_x) / (veclen - 1); for (x = 0; x < veclen; ++x, rx += dx) { ry = spline_eval (num_active_ctlpoints, xv, yv, y2v, rx); if (ry < c->min_y) ry = c->min_y; if (ry > c->max_y) ry = c->max_y; vector[x] = ry; } g_free (mem); break; case GTK_CURVE_TYPE_LINEAR: dx = (c->max_x - min_x) / (veclen - 1); rx = min_x; ry = c->min_y; dy = 0.0; i = first_active; for (x = 0; x < veclen; ++x, rx += dx) { if (rx >= c->ctlpoint[i][0]) { if (rx > c->ctlpoint[i][0]) ry = c->min_y; dy = 0.0; next = i + 1; while (next < c->num_ctlpoints && c->ctlpoint[next][0] <= c->ctlpoint[i][0]) ++next; if (next < c->num_ctlpoints) { delta_x = c->ctlpoint[next][0] - c->ctlpoint[i][0]; dy = ((c->ctlpoint[next][1] - c->ctlpoint[i][1]) / delta_x); dy *= dx; ry = c->ctlpoint[i][1]; i = next; } } vector[x] = ry; ry += dy; } break; case GTK_CURVE_TYPE_FREE: if (c->point) { rx = 0.0; dx = c->num_points / (double) veclen; for (x = 0; x < veclen; ++x, rx += dx) vector[x] = unproject (RADIUS + c->height - c->point[(int) rx].y, c->min_y, c->max_y, c->height); } else memset (vector, 0, veclen * sizeof (vector[0])); break; } } GtkWidget* gtk_curve_new (void) { return gtk_type_new (gtk_curve_get_type ()); } static void gtk_curve_finalize (GObject *object) { GtkCurve *curve; g_return_if_fail (object != NULL); g_return_if_fail (GTK_IS_CURVE (object)); curve = GTK_CURVE (object); if (curve->pixmap) gdk_pixmap_unref (curve->pixmap); if (curve->point) g_free (curve->point); if (curve->ctlpoint) g_free (curve->ctlpoint); G_OBJECT_CLASS (parent_class)->finalize (object); }