[PATCH 2/3] shell: add panel height limiation when moving a window

[Juan Zhao]

On Tue, 2012-07-24 at 10:09 -0400, Kristian Høgsberg wrote:
> On Sun, Jul 22, 2012 at 12:34 PM, Kristian Høgsberg
> <hoegsberg at gmail.com> wrote:
> > On Wed, Jul 18, 2012 at 01:37:59PM +0800, Juan Zhao wrote:
> >> attach file: This patch resolved problem like this.
> >
> > Right, I see.  I think we just need the moving code to restrict the
> > motion so that the point we're dragging (maybe +/- a couple of
> pixels)
> > can't end up under the panel for that.
> 
> I made a drawing:
> 
> https://docs.google.com/drawings/d/1pWHb9jjfTa4GJcDlSsPsbjYUOoMyTL7iENUE178xx4Y/edit 

Limiting the surface not to across the panel is not a good idea. Yeah,
we should consider the condition like this. 

Is it in the condition that, click any area of the window could drag and
move the window? Some user case is, only the title bar area could be
dragged and moved. 

How about implement it in this way?

draw1 introduce the condition:
draw1:
https://docs.google.com/drawings/d/1P_Xx7cilk9WH3ZNgv4P9vQlEZaBytl5bAMYc0dtSxyM/edit


Look at that picture, the shell has a bounding box, if the movement
across the the bounding box, there will be two solutions:
1. if the upper screen is not available, move it just below the panel
(draw2:
https://docs.google.com/drawings/d/1TKYtt41MUHy8wi82TvicN6q_ztMcwkWmSjgTre3DsA0/edit )

2. if the upper screen is available, move the window to that screen
directly. 
(draw3:
https://docs.google.com/drawings/d/13UUFSY9alGeYXksM1aA6P4pfExIWgGQC9mpzPhTdmv4/edit )

And moving left and moving right should is similar to this michanism.

Welcome to add your comments, any further concerns and suggestions?

Thanks,
Juan