# -*- coding: utf-8 -*- # Copyright (c) Vispy Development Team. All Rights Reserved. # Distributed under the (new) BSD License. See LICENSE.txt for more info. """ This module provides an template for creating backends for vispy. It clearly indicates what methods should be implemented and what events should be emitted. """ from __future__ import division from ..base import (BaseApplicationBackend, BaseCanvasBackend, BaseTimerBackend) from ...util import keys from ... import config USE_EGL = config['gl_backend'].lower().startswith('es') # -------------------------------------------------------------------- init --- # Map native keys to vispy keys KEYMAP = { -1: keys.SHIFT, -2: keys.CONTROL, -3: keys.ALT, -4: keys.META, -5: keys.LEFT, -6: keys.UP, -7: keys.RIGHT, -8: keys.DOWN, -9: keys.PAGEUP, -10: keys.PAGEDOWN, -11: keys.INSERT, -12: keys.DELETE, -13: keys.HOME, -14: keys.END, -15: keys.ESCAPE, -16: keys.BACKSPACE, -17: keys.SPACE, -18: keys.ENTER, -19: keys.TAB, -20: keys.F1, -21: keys.F2, -22: keys.F3, -23: keys.F4, -24: keys.F5, -25: keys.F6, -26: keys.F7, -27: keys.F8, -28: keys.F9, -29: keys.F10, -30: keys.F11, -31: keys.F12, } # -------------------------------------------------------------- capability --- # These are all booleans. Note that they mirror many of the kwargs to # the initialization of the Canvas class. capability = dict( # if True they mean: title=False, # can set title on the fly size=False, # can set size on the fly position=False, # can set position on the fly show=False, # can show/hide window XXX ? vsync=False, # can set window to sync to blank resizable=False, # can toggle resizability (e.g., no user resizing) decorate=False, # can toggle decorations fullscreen=False, # fullscreen window support context=False, # can share contexts between windows multi_window=False, # can use multiple windows at once scroll=False, # scroll-wheel events are supported parent=False, # can pass native widget backend parent always_on_top=False, # can be made always-on-top ) # ------------------------------------------------------- set_configuration --- def _set_config(c): """Set gl configuration for template""" raise NotImplementedError # ------------------------------------------------------------- application --- class ApplicationBackend(BaseApplicationBackend): def __init__(self): BaseApplicationBackend.__init__(self) def _vispy_get_backend_name(self): return 'ThisBackendsName' def _vispy_process_events(self): raise NotImplementedError() def _vispy_run(self): raise NotImplementedError() def _vispy_quit(self): raise NotImplementedError() def _vispy_get_native_app(self): raise NotImplementedError() # ------------------------------------------------------------------ canvas --- # You can mix this class with the native widget class CanvasBackend(BaseCanvasBackend): """Template backend Events to emit are shown below. Most backends will probably have one method for each event: self._vispy_canvas.events.initialize() self._vispy_canvas.events.resize(size=(w, h)) self._vispy_canvas.events.draw(region=None) self._vispy_canvas.close() self._vispy_canvas.events.mouse_press(pos=(x, y), button=1, modifiers=()) self._vispy_canvas.events.mouse_release(pos=(x, y), button=1, modifiers=()) self._vispy_canvas.events.mouse_double_click(pos=(x, y), button=1, modifiers=()) self._vispy_canvas.events.mouse_move(pos=(x, y), modifiers=()) self._vispy_canvas.events.mouse_wheel(pos=(x, y), delta=(0, 0), modifiers=()) self._vispy_canvas.events.key_press(key=key, text=text, modifiers=()) self._vispy_canvas.events.key_release(key=key, text=text, modifiers=()) In most cases, if the window-cross is clicked, a native close-event is generated, which should then call canvas.close(). The Canvas class is responsible for firing the close event and calling backend_canvas._vispy_close, which closes the native widget. If this happens to result in a second close event, canvas.close() gets called again, but Canvas knows it is closing so it stops there. If canvas.close() is called (by the user), it calls backend_canvas._vispy_close, which closes the native widget, and we get the same stream of actions as above. This deviation from having events come from the CanvasBackend is necessitated by how different backends handle close events, and the various ways such events can be triggered. """ # args are for BaseCanvasBackend, kwargs are for us. def __init__(self, *args, **kwargs): BaseCanvasBackend.__init__(self, *args) # We use _process_backend_kwargs() to "serialize" the kwargs # and to check whether they match this backend's capability p = self._process_backend_kwargs(kwargs) # Deal with config # ... use context.config # Deal with context p.context.shared.add_ref('backend-name', self) if p.context.shared.ref is self: self._native_context = None # ... else: self._native_context = p.context.shared.ref._native_context # NativeWidgetClass.__init__(self, foo, bar) def _vispy_set_current(self): # Make this the current context raise NotImplementedError() def _vispy_swap_buffers(self): # Swap front and back buffer raise NotImplementedError() def _vispy_set_title(self, title): # Set the window title. Has no effect for widgets raise NotImplementedError() def _vispy_set_size(self, w, h): # Set size of the widget or window raise NotImplementedError() def _vispy_set_position(self, x, y): # Set location of the widget or window. May have no effect for widgets raise NotImplementedError() def _vispy_set_visible(self, visible): # Show or hide the window or widget raise NotImplementedError() def _vispy_set_fullscreen(self, fullscreen): # Set the current fullscreen state raise NotImplementedError() def _vispy_update(self): # Invoke a redraw raise NotImplementedError() def _vispy_close(self): # Force the window or widget to shut down raise NotImplementedError() def _vispy_get_size(self): # Should return widget size raise NotImplementedError() def _vispy_get_position(self): # Should return widget position raise NotImplementedError() def _vispy_get_fullscreen(self): # Should return the current fullscreen state raise NotImplementedError() def _vispy_get_native_canvas(self): # Should return the native widget object. # If this is self, this method can be omitted. return self # ------------------------------------------------------------------- timer --- class TimerBackend(BaseTimerBackend): # Can be mixed with native timer class def __init__(self, vispy_timer): BaseTimerBackend.__init__(self, vispy_timer) def _vispy_start(self, interval): raise NotImplementedError() def _vispy_stop(self): raise NotImplementedError() def _vispy_timeout(self): raise NotImplementedError() def _vispy_get_native_timer(self): # Should return the native widget object. # If this is self, this method can be omitted. return self