diff options
| -rw-r--r-- | src/ld-canvas.c | 77 | ||||
| -rw-r--r-- | src/ld-canvas.h | 3 |
2 files changed, 74 insertions, 6 deletions
diff --git a/src/ld-canvas.c b/src/ld-canvas.c index 5df3438..1c48325 100644 --- a/src/ld-canvas.c +++ b/src/ld-canvas.c @@ -37,6 +37,13 @@ /* The default screen resolution in DPI units. */ #define DEFAULT_SCREEN_RESOLUTION 96 +/* The maximal, minimal and default values of zoom. */ +#define ZOOM_MIN 0.01 +#define ZOOM_MAX 100 +#define ZOOM_DEFAULT 1 +/* Multiplication factor for zooming with mouse wheel. */ +#define ZOOM_WHEEL_STEP 1.4 + /* When drawing is requested, extend all sides of * the rectangle to be drawn by this number of pixels. */ @@ -156,7 +163,8 @@ enum { PROP_0, PROP_DIAGRAM, - PROP_LIBRARY + PROP_LIBRARY, + PROP_ZOOM }; static void ld_canvas_get_property (GObject *object, guint property_id, @@ -272,6 +280,16 @@ ld_canvas_class_init (LdCanvasClass *klass) g_object_class_install_property (object_class, PROP_LIBRARY, pspec); /** + * LdCanvas:zoom: + * + * The zoom of this canvas. + */ + pspec = g_param_spec_double ("zoom", "Zoom", + "The zoom of this canvas.", + ZOOM_MIN, ZOOM_MAX, ZOOM_DEFAULT, G_PARAM_READWRITE); + g_object_class_install_property (object_class, PROP_ZOOM, pspec); + +/** * LdCanvas::set-scroll-adjustments: * @horizontal: The horizontal #GtkAdjustment. * @vertical: The vertical #GtkAdjustment. @@ -309,7 +327,7 @@ ld_canvas_init (LdCanvas *self) self->priv->x = 0; self->priv->y = 0; - self->priv->zoom = 1; + self->priv->zoom = ZOOM_DEFAULT; ld_canvas_color_set (COLOR_GET (self, COLOR_BASE), 1, 1, 1, 1); ld_canvas_color_set (COLOR_GET (self, COLOR_GRID), 0.5, 0.5, 0.5, 1); @@ -377,6 +395,9 @@ ld_canvas_get_property (GObject *object, guint property_id, case PROP_LIBRARY: g_value_set_object (value, ld_canvas_get_library (self)); break; + case PROP_ZOOM: + g_value_set_double (value, ld_canvas_get_zoom (self)); + break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); } @@ -397,6 +418,9 @@ ld_canvas_set_property (GObject *object, guint property_id, case PROP_LIBRARY: ld_canvas_set_library (self, LD_LIBRARY (g_value_get_object (value))); break; + case PROP_ZOOM: + ld_canvas_set_zoom (self, g_value_get_double (value)); + break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); } @@ -742,6 +766,49 @@ ld_canvas_diagram_to_widget_coords (LdCanvas *self, *wy = scale * (dy - self->priv->y) + 0.5 * widget->allocation.height; } +/** + * ld_canvas_get_zoom: + * @self: An #LdCanvas object. + * + * Return value: Zoom of the canvas. + */ +gdouble +ld_canvas_get_zoom (LdCanvas *self) +{ + g_return_val_if_fail (LD_IS_CANVAS (self), -1); + return self->priv->zoom; +} + +/** + * ld_canvas_set_zoom: + * @self: An #LdCanvas object. + * @zoom: The zoom. + * + * Set zoom of the canvas. + */ +void +ld_canvas_set_zoom (LdCanvas *self, gdouble zoom) +{ + gdouble clamped_zoom; + + g_return_if_fail (LD_IS_CANVAS (self)); + + clamped_zoom = CLAMP (zoom, ZOOM_MIN, ZOOM_MAX); + if (self->priv->zoom == clamped_zoom) + return; + + self->priv->zoom = clamped_zoom; + + /* TODO: Retrieve the position of the mouse and call + * check_terminals() instead of just hiding the terminals. + */ + hide_terminals (self); + update_adjustments (self); + gtk_widget_queue_draw (GTK_WIDGET (self)); + + g_object_notify (G_OBJECT (self), "zoom"); +} + /* ===== Operations ======================================================== */ @@ -1149,10 +1216,10 @@ on_scroll (GtkWidget *widget, GdkEventScroll *event, gpointer user_data) switch (event->direction) { case GDK_SCROLL_UP: - self->priv->zoom *= 1.5; + ld_canvas_set_zoom (self, self->priv->zoom * ZOOM_WHEEL_STEP); break; case GDK_SCROLL_DOWN: - self->priv->zoom /= 1.5; + ld_canvas_set_zoom (self, self->priv->zoom / ZOOM_WHEEL_STEP); break; default: return FALSE; @@ -1165,9 +1232,7 @@ on_scroll (GtkWidget *widget, GdkEventScroll *event, gpointer user_data) self->priv->x += prev_x - new_x; self->priv->y += prev_y - new_y; - update_adjustments (self); check_terminals (self, event->x, event->y); - gtk_widget_queue_draw (widget); return TRUE; } diff --git a/src/ld-canvas.h b/src/ld-canvas.h index 3bbcac6..702f2fe 100644 --- a/src/ld-canvas.h +++ b/src/ld-canvas.h @@ -78,6 +78,9 @@ void ld_canvas_widget_to_diagram_coords (LdCanvas *self, void ld_canvas_diagram_to_widget_coords (LdCanvas *self, gdouble dx, gdouble dy, gdouble *wx, gdouble *wy); +gdouble ld_canvas_get_zoom (LdCanvas *self); +void ld_canvas_set_zoom (LdCanvas *self, gdouble zoom); + void ld_canvas_add_object_begin (LdCanvas *self, LdDiagramObject *object); /* TODO: The rest of the interface. */ |