(svn r17915) -Codechange: Allow windows to compute their own initial position.

src/window.cpp

@@ -1310,6 +1310,11 @@ static Point LocalGetWindowPlacement(const WindowDesc *desc, int16 sm_width, int
 	return pt;
 }
 
+/* virtual */ Point Window::OnInitialPosition(const WindowDesc *desc, int16 sm_width, int16 sm_height, int window_number)
+{
+	return LocalGetWindowPlacement(desc, sm_width, sm_height, window_number);
+}
+
 /**
  * Set the positions of a new window from a WindowDesc and open it.
  *
@@ -1356,7 +1361,7 @@ void Window::FinishInitNested(const WindowDesc *desc, WindowNumber window_number
 {
 	this->InitializeData(desc->cls, NULL, window_number);
 	this->desc_flags = desc->flags;
-	Point pt = LocalGetWindowPlacement(desc, this->nested_root->smallest_x, this->nested_root->smallest_y, window_number);
+	Point pt = this->OnInitialPosition(desc, this->nested_root->smallest_x, this->nested_root->smallest_y, window_number);
 	this->InitializePositionSize(pt.x, pt.y, this->nested_root->smallest_x, this->nested_root->smallest_y);
 	this->FindWindowPlacementAndResize(desc->default_width, desc->default_height);
 }

src/window_gui.h

@@ -638,6 +638,18 @@ public:
 
 	/*** Event handling ***/
 
+	/**
+	 * Compute the initial position of the window.
+	 * @param *desc         The pointer to the WindowDesc of the window to create.
+	 * @param sm_width      Smallest width of the window.
+	 * @param sm_height     Smallest height of the window.
+	 * @param window_number The window number of the new window.
+	 * @return Initial position of the top-left corner of the window.
+	 *
+	 * @note Due to the way C++ works, only windows with nested widgets can usefully override this function.
+	 */
+	virtual Point OnInitialPosition(const WindowDesc *desc, int16 sm_width, int16 sm_height, int window_number);
+
 	/**
 	 * The window must be repainted.
 	 * @note This method should not change any state, it should only use drawing functions.