diff options
Diffstat (limited to 'liblogdiag/ld-canvas.c')
| -rw-r--r-- | liblogdiag/ld-canvas.c | 60 |
1 files changed, 56 insertions, 4 deletions
diff --git a/liblogdiag/ld-canvas.c b/liblogdiag/ld-canvas.c index de24513..60da2e5 100644 --- a/liblogdiag/ld-canvas.c +++ b/liblogdiag/ld-canvas.c @@ -33,8 +33,8 @@ #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 +/* Multiplication factor for zooming. */ +#define ZOOM_STEP 1.4 /* When drawing is requested, extend all sides of * the rectangle to be drawn by this number of pixels. @@ -862,6 +862,58 @@ ld_canvas_set_zoom (LdCanvas *self, gdouble zoom) g_object_notify (G_OBJECT (self), "zoom"); } +/** + * ld_canvas_can_zoom_in: + * @self: an #LdCanvas object. + * + * Return value: %TRUE if the view can be zoomed in. + */ +gboolean +ld_canvas_can_zoom_in (LdCanvas *self) +{ + g_return_val_if_fail (LD_IS_CANVAS (self), FALSE); + return self->priv->zoom < ZOOM_MAX; +} + +/** + * ld_canvas_can_zoom_out: + * @self: an #LdCanvas object. + * + * Return value: %TRUE if the view can be zoomed out. + */ +gboolean +ld_canvas_can_zoom_out (LdCanvas *self) +{ + g_return_val_if_fail (LD_IS_CANVAS (self), FALSE); + return self->priv->zoom > ZOOM_MIN; +} + +/** + * ld_canvas_zoom_in: + * @self: an #LdCanvas object. + * + * Zoom the view in. + */ +void +ld_canvas_zoom_in (LdCanvas *self) +{ + g_return_if_fail (LD_IS_CANVAS (self)); + ld_canvas_set_zoom (self, self->priv->zoom * ZOOM_STEP); +} + +/** + * ld_canvas_zoom_out: + * @self: an #LdCanvas object. + * + * Zoom the view out. + */ +void +ld_canvas_zoom_out (LdCanvas *self) +{ + g_return_if_fail (LD_IS_CANVAS (self)); + ld_canvas_set_zoom (self, self->priv->zoom / ZOOM_STEP); +} + /* ===== Operations ======================================================== */ @@ -1288,10 +1340,10 @@ on_scroll (GtkWidget *widget, GdkEventScroll *event, gpointer user_data) switch (event->direction) { case GDK_SCROLL_UP: - ld_canvas_set_zoom (self, self->priv->zoom * ZOOM_WHEEL_STEP); + ld_canvas_zoom_in (self); break; case GDK_SCROLL_DOWN: - ld_canvas_set_zoom (self, self->priv->zoom / ZOOM_WHEEL_STEP); + ld_canvas_zoom_out (self); break; default: return FALSE; |