[SOLVED]Start Drag from GeUserArea

Helper

On 08/06/2017 at 08:14, xxxxxxxx wrote:

Sorry my first post was missing information.
MouseDrag() has to be called first in the loop for each drag event. Then the current input state for the mouse left button has to be retrieved before checking c4d.BFM_INPUT_VALUE.
So the dragging loop would be:

mx = mousex
my = mousey
state = c4d.BaseContainer()
while True:
  
    result, dx, dy, channels = self.MouseDrag()
    if result == c4d.MOUSEDRAGRESULT_ESCAPE:
      break
  
    if not self.GetInputState(c4d.BFM_INPUT_MOUSE, c4d.BFM_INPUT_MOUSELEFT, state) :
        break
  
    if state[c4d.BFM_INPUT_VALUE] == 0:
        print "Released Left Mouse"
        break
  
    if dx == 0 and dy == 0:
        continue
  
    mx += dx
    my += dy
    print "Mouse Dragging at position [%f,%f]" % (mx, my)

state[c4d.BFM_INPUT_VALUE] gives the mouse left button clicked state. So this allows to check when the mouse button has been released.
If the mouse position hasn't changed then no dragging should be processed.

You can change the mouse icon with gui.SetMousePointer().

Helper

On 08/06/2017 at 09:38, xxxxxxxx wrote:

Thanks you. Tested and solved !

Helper

On 09/06/2017 at 00:54, xxxxxxxx wrote:

Sorry to bump this thread but is there a way for start drag from a GeUserArea and recieve drop message from TreeViewCustomGui? Or at least is it possible to send message to this TreeViewCustomGui? Or a timer?
Just tell me yes or no

Cause I think I must do the following thing but I prefer ask if there is no other way before ^^
Make my timer function into my GeDialog who call a custom timer function inside my TreeView

Helper

On 09/06/2017 at 02:29, xxxxxxxx wrote:

GeUserArea.HandleMouseDrag() is missing in the Python API so it would be really difficult and hacky to send drag and drop data to other gadgets.

Helper

On 09/06/2017 at 02:46, xxxxxxxx wrote:

Ok thanks for confirming !

Helper

On 09/06/2017 at 13:53, xxxxxxxx wrote:

Sorry again to bump this thread, but I don't udnerstand the output code while the mouse is not moving, delta y is always -22 while it should be 0

    def InputEvent(self, msg) :
        mousex = msg[c4d.BFM_INPUT_X]
        mousey = msg[c4d.BFM_INPUT_Y]
  
        self.MouseDragStart(c4d.KEY_MLEFT, mousex, mousey, c4d.MOUSEDRAGFLAGS_DONTHIDEMOUSE | c4d.MOUSEDRAGFLAGS_NOMOVE)
  
        start_x = mousex
        start_y = mousey
  
        mx = mousex
        my = mousey
        state = c4d.BaseContainer()
        while True:
  
            result, dx, dy, channels = self.MouseDrag()
            if result == c4d.MOUSEDRAGRESULT_ESCAPE:
                break
  
            if not self.GetInputState(c4d.BFM_INPUT_MOUSE, c4d.BFM_INPUT_MOUSELEFT, state) :
                break
  
            if state[c4d.BFM_INPUT_VALUE] == 0:
                print "Released Left Mouse"
                break
  
            if dx == 0 and dy == 0: #dy != 0 while not moving
                continue
  
            mx += dx
            my += dy
  
           #Should not be display if not moving
           print 'drag'
  
        print start_x - mx
        print start_y - my #-22 if not moving
  
        return True

Helper

On 12/06/2017 at 07:06, xxxxxxxx wrote:

Originally posted by xxxxxxxx

Sorry again to bump this thread, but I don't understand the output code while the mouse is not moving, delta y is always -22 while it should be 0

If the mouse doesn't move dx and dy are 0. The final mouse delta X and Y values depends on how you calculate the current mouse position.
It's better to subtract the mouse drag delta values:

mx -= dx
my -= dy

Then the final delta value can be calculated:
print mx - mousex
print my - mousey

If you don't want MouseDrag() to return when the mouse doesn't move, don't pass MOUSEDRAGFLAGS_NOMOVE to MouseDragStart().

Helper

On 13/06/2017 at 04:52, xxxxxxxx wrote:

Ok I get why it's wrong... The corect loop initialization is:

        mousex = msg[c4d.BFM_INPUT_X]
        mousey = msg[c4d.BFM_INPUT_Y]
        
        self.MouseDragStart(c4d.KEY_MLEFT, mousex, mousey, c4d.MOUSEDRAGFLAGS_DONTHIDEMOUSE | c4d.MOUSEDRAGFLAGS_NOMOVE)
        
        while self.MouseDrag()[0] == c4d.MOUSEDRAGRESULT_CONTINUE:
            if msg[c4d.BFM_INPUT_VALUE] == 0:
                break
            
            result, dx, dy, channels = self.MouseDrag()
            print "dx {} - dy {}".format(dx, dy)

While in the documention of https://developers.maxon.net/docs/py/2023_2/modules/c4d.gui/EditorWindow/index.html#EditorWindow.MouseDragStart the main drag loop is done with While true, which give you a wrong value for dx/dy for the first packet of the drag input.

So doing it like in the C++ exemple

    win->MouseDragStart(button, mouseX, mouseY, MOUSEDRAGFLAGS_DONTHIDEMOUSE | MOUSEDRAGFLAGS_NOMOVE);
    while (win->MouseDrag(&dx, &dy, &device) == MOUSEDRAGRESULT_CONTINUE)

give us in python

        self.MouseDragStart(c4d.KEY_MLEFT, mousex, mousey, c4d.MOUSEDRAGFLAGS_DONTHIDEMOUSE | c4d.MOUSEDRAGFLAGS_NOMOVE)
        
        while self.MouseDrag()[0] == c4d.MOUSEDRAGRESULT_CONTINUE:

Anyway thanks for your support !

Helper

On 13/06/2017 at 08:18, xxxxxxxx wrote:

I can't confirm that because the delta values returned from the call to MouseDrag()[0] aren't processed for each while loop:

while self.MouseDrag()[0] == c4d.MOUSEDRAGRESULT_CONTINUE: # dx, dy and channels not retrieved and processed

There should be only one MouseDrag() call for each while loop.

Helper

On 13/06/2017 at 08:28, xxxxxxxx wrote:

Juste copy paste thoses two codes and do a normal click without dragging. Just a simple click (no move, nothing just a click), So result should be 0 and 0 for dx/dy in all case (in all packet of the drag pool)
The first one give correct result for dx , dy

import c4d
  
class Area(c4d.gui.GeUserArea) :
  
    def InputEvent(self, msg) :
        mousex = msg[c4d.BFM_INPUT_X]
        mousey = msg[c4d.BFM_INPUT_Y]
        
        self.MouseDragStart(c4d.KEY_MLEFT, mousex, mousey, c4d.MOUSEDRAGFLAGS_DONTHIDEMOUSE | c4d.MOUSEDRAGFLAGS_NOMOVE)
        
        while self.MouseDrag()[0]:
            if msg[c4d.BFM_INPUT_VALUE] == 0:
                break
            
            result, dx, dy, channels = self.MouseDrag()
            if result!=c4d.MOUSEDRAGRESULT_CONTINUE: break
            
            print "dx {} - dy {}".format(dx, dy)
                        
        return True
  
class MyDialog(c4d.gui.GeDialog) :
    def CreateLayout(self) :
        self.area = Area()
        
        self.AddUserArea(1000, c4d.BFH_SCALEFIT|c4d.BFV_SCALEFIT)
        self.AttachUserArea(self.area, 1000)
        return True
  
def main() :
    dialog = MyDialog()
    dialog.Open(dlgtype=c4d.DLG_TYPE_MODAL_RESIZEABLE, defaultw=500, defaulth=500)
  
if __name__=='__main__':
    main()

While the sdk code(using While True) give wrong result for dx, dy in the first packet (dx 4 and dy 4)

import c4d
  
class Area(c4d.gui.GeUserArea) :
  
    def InputEvent(self, msg) :
        mousex = msg[c4d.BFM_INPUT_X]
        mousey = msg[c4d.BFM_INPUT_Y]
        
        self.MouseDragStart(c4d.KEY_MLEFT, mousex, mousey, c4d.MOUSEDRAGFLAGS_DONTHIDEMOUSE | c4d.MOUSEDRAGFLAGS_NOMOVE)
        
        while True:
            if msg[c4d.BFM_INPUT_VALUE] == 0:
                break
            
            result, dx, dy, channels = self.MouseDrag()
            if result!=c4d.MOUSEDRAGRESULT_CONTINUE: break
            
            print "dx {} - dy {}".format(dx, dy)
                        
        return True
  
class MyDialog(c4d.gui.GeDialog) :
    def CreateLayout(self) :
        self.area = Area()
        
        self.AddUserArea(1000, c4d.BFH_SCALEFIT|c4d.BFV_SCALEFIT)
        self.AttachUserArea(self.area, 1000)
        return True
  
def main() :
    dialog = MyDialog()
    dialog.Open(dlgtype=c4d.DLG_TYPE_MODAL_RESIZEABLE, defaultw=500, defaulth=500)
  
if __name__=='__main__':
    main()

Helper

On 14/06/2017 at 03:17, xxxxxxxx wrote:

You're not retrieving and printing the delta values dx and dy from the self.MouseDrag()[0] calls in the first script. The delta values are 4.0 for the first mouse drag there too.

The limitation with MouseDrag() in Python is the language doesn't support assignments in expressions.