Re: Mouse cursor out of place?

[Eric Wasylishen]

Hey,
I think I tracked down the bug..

Plug.tiff had it's dpi set to 15 or so, so the point size was about 230x230. 
The drag icon window was then set to that size (in pixels). 

The problem seems to be the following call, in  -[GSDragView 
_setupWindowFor:mousePosition:imagePosition:]:

  // Only display the image
  [GSServerForWindow(_window) restrictWindow: [_window windowNumber]
                                     toImage: [dragCell image]];

which doesn't seem to work properly with images with a DPI != 72.

As a quick fix you can set plug.tiff to 72dpi (using imagemagick: mogrify 
-density 72x72 plug.tiff).

a couple other notes:
- If I do a [[self window] setBackgroundColor: [NSColor clearColor]] in 
GSDragView, the drag icon shows up with proper alpha transparency for me - 
since I'm using cairo and a compositing window manager.
- _setupWindowFor:mousePosition:imagePosition: uses [image size] to set the 
window frame - this isn't safe with resolution independence; it should set the 
window content size instead.
- I'm not sure what we should do to the -restrictWindow:toImage: method; 
haven't looked at how it's implemented.

Cheers,
Eric

On 2011-06-23, at 5:04 PM, Bluna Ratimonkey wrote:

> Thanks Eric, and especially for letting me see it somewhere else for
> the first time :)
> 
> 
> BTW, do you guys think we could use something like virtual window that
> didn't actually get mapped but blend the image with XcursorImage so
> image doesn't have a chance to jump on load and only map the window on
> slide back?
> 
> On Fri, Jun 24, 2011 at 5:17 AM, Eric Wasylishen <address@hidden> wrote:
>> I just did a little debugging on this.. I got down to -[GSDragView 
>> _setupWindowFor:mousePosition:imagePosition:] and the coordinates passed in 
>> to here are correct. The frame that is set on _window in that method is 
>> correct, but the place where the window actually shows up is at about double 
>> the y-coordinate of where it should.
>> 
>> I attached a screenshot. I started the drag at around (184, 180) in screen 
>> coordinates, which is what iPoint is. You can see that _window reports it 
>> has a frame origin at that point, but it actually appear on screen around 
>> (184, 360).
>> 
>> -Eric
>> 
>> 
>> 
>> 
>> 
>> 
>> On 2011-06-23, at 3:53 PM, Bluna Ratimonkey wrote:
>> 
>>> Oh sorry,
>>> the mouse down was
>>> 
>>> NSPoint mouseDownPoint = [self convertPointFromBase:[anEvent 
>>> locationInWindow]];
>>> 
>>> I tried this instead without success though. Was wondering if I should do 
>>> this.
>>> 
>>>                               [self dragImage:[NSImage 
>>> imageNamed:@"Plug.tiff"]
>>>                                       at:[self 
>>> convertPointFromBase:[anEvent locationInWindow]]
>>>                                       offset:NSZeroSize
>>>                                       event:anEvent
>>>                                       pasteboard:pb
>>>                                       source:mouseDownPort
>>>                                       slideBack:YES];
>>> 
>>> The case is in TMNodeView.m line 842
>>> Thanks,
>>> Bluna
>> 
>> 
>> 
> 
> 
> 
> -- 
> /* Join Bluna Ratimonkey (漫画家) and build the real future for GNUstep ! */
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