playbackTool.py

# ========================================================================== #
# PlaybackTool
# ========================================================================== #
'''
A simple hotkey setup to mimic the playback and scrub functionality of proprietary animation software from the big studios.

Originally written by Joe Holmark then ~~expanded~~ messed with by Daniel Klug.


## Usage:
PlaybackTool will play/pause playback with a **quick tap**. If you **press and hold**
the hotkey, you can also **left click and drag** to scrub the timeline.

If you **tap the toggle** key during playback, it will restart playback from the
start frame.

If you **tap the toggle** key any other time, it will flip between the start and
end frame of the last scrub or playback.


## Installation:
Place the **playbackTool.py** file in your _~/maya/scripts_ folder.

3 hotkeys need to be made - PRESS, RELEASE, and Toggle.

The preferred hotkey for PRESS and RELEASE is Space.
For the toggle, use shift-space.

```python
#PRESS
from PlaybackTool import playbackTool
playbackTool.press()
```

```python
#RELEASE
playbackTool.release()
```
```python
#Toggle
from PlaybackTool import playbackTool
playbackTool.toggle()
```

## Current limitation:
- PlaybackTool will not yet register manual clicks or scrubs in the timeline for the toggle functionality to work.
- PlaybackTool flashes in&out of the scrub context when quick-tapping.

'''
# -------------------------------------------------------------------------- #
# Imports

import maya.api.OpenMayaUI as apiUI
import maya.api.OpenMaya as api
from maya import cmds, mel
import time

# -------------------------------------------------------------------------- #
# Globals

playbackFPS = 24  # Personal pref

TIME_START = 0
isPlaying = False
firstFrame, lastFrame = [0, 0]

# -------------------------------------------------------------------------- #
# Functions

def press():
    global TIME_START, isPlaying, firstFrame

    # Start the timer
    TIME_START = time.time()

    isPlaying = cmds.play(q=True, state=True)

    if isPlaying:
        cmds.play(state = False)
    else:
        firstFrame = cmds.currentTime(q=True)

    # The only annoying thing is the flashing in&out of the scrub context
    # whether or not we use it.
    # TODO: Investigate a workaround that doesn't use callbacks.
    mel.eval('storeLastAction( "restoreLastContext " + `currentCtx` )')
    cmds.setToolTo( 'TimeDragger' )

def release():
    global lastFrame

    lastFrame  = cmds.currentTime(q=True)

    mel.eval('invokeLastAction')

    if (time.time() - TIME_START) < 0.15:  # Quick button press
        if not isPlaying:
            cmds.playbackOptions(edit=True, playbackSpeed = playbackFPS / 24.0)
            cmds.play(state = True)

def toggle():
    global firstFrame, lastFrame, isPlaying

    isPlaying = cmds.play(q=True, state=True)

    if isPlaying:  # Or else Maya will ignore the playhead
        cmds.play(state=False)

    cmds.currentTime(firstFrame)

    if isPlaying:
        cmds.play(state=True)

    firstFrame, lastFrame = lastFrame, firstFrame

# ========================================================================== #
# Notes
'''
from PlaybackTool import playbackTool
reload(playbackTool)
print playbackTool.firstFrame, playbackTool.lastFrame  # Fuck yes
'''