position a gui element in corner of windows - track resizes?

[pootle]

I want to position a couple of buttons in the window corners, and reposition them if the user resizes the window, but I can't see how to find the window's size, or detect when it is resized.

[paddywwoof]

Good point. I see there's a TODO in DisplayOpenGL on that subject. It's probably rather difficult to do in your code as it needs an additional event mask setting up in DisplayOpenGL and the event checking in Display needs to catch resizes. i.e. DisplayOpenGL

      xlib.XSelectInput(self.d, self.window, KeyPressMask | KeyReleaseMask | ResizeRedirectMask)

and Display

      n = xlib.XEventsQueued(self.opengl.d, xlib.QueuedAfterFlush)
      for _ in range(n):
          xlib.XNextEvent(self.opengl.d, self.ev)
          if self.ev.type == KeyPress or self.ev.type == KeyRelease:
              self.event_list.append(self.ev)
          elif self.ev.type == ClientMessage:
            if (self.ev.xclient.data.l[0] == self.opengl.WM_DELETE_WINDOW.value):
              self.destroy()
          elif self.ev.type == ResizeRequest:
            (self.width, self.height) = (self.ev.xresizerequest.width,
                                         self.ev.xresizerequest.height)
            opengles.glViewport(0, 0, self.width, self.height)
            self.was_resized = True

then in programs

    if DISPLAY.was_resized:
        # move shapes and fix camera

However the the normal Camera.reset() with different lens settings doesn't work properly and creating new Cameras and setting Shape._camera = new_cam also has issues. I will let you know when I've figured out what to do, and will post the revisions to pi3d develop branch. Hopefully something quick to do.

Paddy

PS to answer the first part of your question. You can get the Display size using its width and height properties. So if your button is bwxbh it will be in the bottom right corner:

...
button.positionX((display.width - bw) * 0.5)
button.positionY((diplay.height - bh) * 0.5)

[pootle]

Many thanks, that'll keep me going