diff --git a/redo/objimpl/control.c b/redo/objimpl/control.c
new file mode 100644
index 00000000..31f5f125
--- /dev/null
+++ b/redo/objimpl/control.c
@@ -0,0 +1,112 @@
+// 26 may 2015
+#include "out/ui.h"
+#include "uipriv.h"
+
+struct controlBase {
+	uiControl *parent;
+	int hidden;
+	int disabled;
+};
+
+#define controlBase(c) ((struct controlBase *) (TODO))
+
+void controlBaseDestroy(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	if (cb->parent != NULL)
+		complain("attempt to destroy uiControl %p while it has a parent", c);
+	uiControlCommitDestroy(c);
+	// TODO free memory
+}
+
+uiControl *controlBaseParent(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	return cb->parent;
+}
+
+void controlBaseSetParent(uiControl *c, uiControl *parent)
+{
+	struct controlBase *cb = controlBase(c);
+
+	if (parent != NULL && cb->parent != NULL)
+		complain("attempt to reparent uiControl %p (has parent %p, attempt to give parent %p)", c, cb->parent, parent);
+	if (parent == NULL && cb->parent == NULL)
+		complain("attempt to double unparent uiControl %p", c);
+	cb->parent = parent;
+	uiControlCommitSetParent(c, parent);
+}
+
+int controlBaseContainerVisible(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	if (cb->hidden)
+		return 0;
+	if (cb->parent == NULL)
+		return 1;
+	return uiControlContainerVisible(cb->parent);
+}
+
+void controlBaseShow(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	cb->hidden = 0;
+	uiControlUpdateState(c);
+}
+
+void controlBaseHide(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	cb->hidden = 1;
+	uiControlUpdateState(c);
+}
+
+int controlBaseContainerEnabled(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	if (cb->disabled)
+		return 0;
+	if (cb->parent == NULL)
+		return 1;
+	return uiControlContainerEnabled(cb->parent);
+}
+
+void controlBaseEnable(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	cb->disabled = 0;
+	uiControlUpdateState(c);
+}
+
+void controlBaseDisable(uiControl *c)
+{
+	struct controlBase *cb = controlBase(c);
+
+	cb->disabled = 1;
+	uiControlUpdateState(c);
+}
+
+void controlBaseUpdateState(uiControl *c)
+{
+	if (uiControlContainerVisible(c))
+		uiControlCommitShow(c);
+	else
+		uiControlCommitHide(c);
+	if (uiControlContainerEnabled(c))
+		uiControlCommitEnable(c);
+	else
+		uiControlCommitDisable(c);
+	uiControlContainerUpdateState(c);
+}
+
+void controlBaseContainerUpdateState(uiControl *c)
+{
+	// by default not a contianer; do nothing
+}