X-Git-Url: https://git.dlugolecki.net.pl/?a=blobdiff_plain;f=src%2Fui%2Fdrawing_area.c;h=16448474091ed73e66c535cb5477e5ef3a713bbd;hb=HEAD;hp=8eefe5fc8015349391173c79f18e67c201f21c85;hpb=48f2a54d99885de03c52451ec2fb546ac35d78ab;p=familia.git

diff --git a/src/ui/drawing_area.c b/src/ui/drawing_area.c
index 8eefe5f..1644847 100644
--- a/src/ui/drawing_area.c
+++ b/src/ui/drawing_area.c
@@ -2,8 +2,10 @@
 #include <gtk/gtkgl.h>
 #include <GL/gl.h>
 #include <GL/glu.h>
+#include <assert.h>
 
 #include "../debug.h"
+#include "../familia.h"
 #include "drawing_area.h"
 #include "../math/3d.h"
 #include "../graphics/constants.h"
@@ -148,3 +150,47 @@ void drawing_area_unrealize (GtkWidget *widget, gpointer data)
 {
 	/* Code */
 }
+
+/**
+ * The "scroll-event" signal handler. Responsible for correctly scrolling
+ * drawing area using mouse or touchpad.
+ */
+void drawing_area_event_scroll (GtkWidget *widget,
+				GdkEvent *event, FamiliaData *data)
+{
+	GtkAdjustment *adjustment = NULL;
+	gdouble value = 0;
+	gdouble step = 0;
+
+	assert(event->type == GDK_SCROLL);
+
+	switch(event->scroll.direction) {
+		case GDK_SCROLL_UP:
+			adjustment = data->vadjustment;
+			step = 1;
+			break;
+		case GDK_SCROLL_DOWN:
+			adjustment = data->vadjustment;
+			step = -1;
+			break;
+		case GDK_SCROLL_LEFT:
+			adjustment = data->hadjustment;
+			step = -1;
+			break;
+		case GDK_SCROLL_RIGHT:
+			adjustment = data->hadjustment;
+			step = 1;
+			break;
+		default:
+			break;
+	}
+
+	if (adjustment != NULL) {
+		value = gtk_adjustment_get_value (adjustment);
+		step  = step * gtk_adjustment_get_step_increment(adjustment);
+		value += step;
+
+		gtk_adjustment_set_value (adjustment, value);
+		gtk_adjustment_value_changed (adjustment);
+	}
+}