Restructured code.

Most non-GUI code was moved out of mapwidget.go

1 files changed, 13 insertions, 0 deletions

diff --git a/emptyPixmap.go b/emptyPixmap.go
new file mode 100644
index 0000000..7635225
--- /dev/null
+++ b/emptyPixmap.go
@@ -0,0 +1,13 @@
+package main
+
+import (
+	"github.com/mattn/go-gtk/gdk"
+)
+
+// emptyPixmap creates an empty pixmap.
+func emptyPixmap(w, h, depth int) *gdk.Pixmap {
+	// The underlying C function would create an empty, unbound pixmap, if the drawable paramater was a NULL pointer.
+	// Since simply passing a nil value would result in a panic (dereferencing a nil pointer), we use a new gdk.Drawable.
+	// gdk.Drawable contains a C pointer which is NULL by default. So passing a new(gdk.Drawable) does the trick.
+	return gdk.NewPixmap(new(gdk.Drawable), w, h, depth)
+}