Source code for napari._qt.qt_viewer

from __future__ import annotations

import logging
import sys
import traceback
import typing
import warnings
from pathlib import Path
from typing import TYPE_CHECKING, List, Optional, Sequence, Tuple, Union
from weakref import WeakSet, ref

import numpy as np
from qtpy.QtCore import QCoreApplication, QObject, Qt
from qtpy.QtGui import QCursor, QGuiApplication
from qtpy.QtWidgets import QFileDialog, QSplitter, QVBoxLayout, QWidget

from napari._qt.containers import QtLayerList
from napari._qt.dialogs.qt_reader_dialog import handle_gui_reading
from napari._qt.dialogs.screenshot_dialog import ScreenshotDialog
from napari._qt.perf.qt_performance import QtPerformance
from napari._qt.utils import (
from napari._qt.widgets.qt_dims import QtDims
from napari._qt.widgets.qt_viewer_buttons import (
from napari._qt.widgets.qt_viewer_dock_widget import QtViewerDockWidget
from napari._qt.widgets.qt_welcome import QtWidgetOverlay
from import Camera
from napari.components.layerlist import LayerList
from napari.components.overlays import CanvasOverlay, Overlay, SceneOverlay
from napari.errors import MultipleReaderError, ReaderPluginError
from napari.layers.base.base import Layer
from napari.plugins import _npe2
from napari.settings import get_settings
from napari.settings._application import DaskSettings
from napari.utils import config, perf, resize_dask_cache
from napari.utils._proxies import ReadOnlyWrapper
from napari.utils.action_manager import action_manager
from napari.utils.colormaps.standardize_color import transform_color
from napari.utils.history import (
from napari.utils.interactions import (
from import imsave
from napari.utils.key_bindings import KeymapHandler
from napari.utils.misc import in_ipython, in_jupyter
from napari.utils.theme import get_theme
from napari.utils.translations import trans
from import imsave_extensions

from napari._vispy import (  # isort:skip

    from npe2.manifest.contributions import WriterContribution

    from napari._qt.layer_controls import QtLayerControlsContainer
    from napari.components import ViewerModel
    from import Event

def _npe2_decode_selected_filter(
    ext_str: str, selected_filter: str, writers: Sequence[WriterContribution]
) -> Optional[WriterContribution]:
    """Determine the writer that should be invoked to save data.

    When npe2 can be imported, resolves a selected file extension
    string into a specific writer. Otherwise, returns None.
    # When npe2 is not present, `writers` is expected to be an empty list,
    # `[]`. This function will return None.

    for entry, writer in zip(
        if entry.startswith(selected_filter):
            return writer
    return None

def _extension_string_for_layers(
    layers: Sequence[Layer],
) -> Tuple[str, List[WriterContribution]]:
    """Return an extension string and the list of corresponding writers.

    The extension string is a ";;" delimeted string of entries. Each entry
    has a brief description of the file type and a list of extensions.

    The writers, when provided, are the
    objects. There is one writer per entry in the extension string. If npe2
    is not importable, the list of writers will be empty.
    # try to use npe2
    ext_str, writers = _npe2.file_extensions_string_for_layers(layers)
    if ext_str:
        return ext_str, writers

    # fallback to old behavior

    if len(layers) == 1:
        selected_layer = layers[0]
        # single selected layer.
        if selected_layer._type_string == 'image':
            ext = imsave_extensions()

            ext_list = [f"*{val}" for val in ext]
            ext_str = ';;'.join(ext_list)

            ext_str = trans._(
                "All Files (*);; Image file types:;;{ext_str}",

        elif selected_layer._type_string == 'points':
            ext_str = trans._("All Files (*);; *.csv;;")

            # layer other than image or points
            ext_str = trans._("All Files (*);;")

        # multiple layers.
        ext_str = trans._("All Files (*);;")
    return ext_str, []

[docs]class QtViewer(QSplitter): """Qt view for the napari Viewer model. Parameters ---------- viewer : napari.components.ViewerModel Napari viewer containing the rendered scene, layers, and controls. show_welcome_screen : bool, optional Flag to show a welcome message when no layers are present in the canvas. Default is `False`. Attributes ---------- canvas : vispy.scene.SceneCanvas Canvas for rendering the current view. console : QtConsole IPython console terminal integrated into the napari GUI. controls : QtLayerControlsContainer Qt view for GUI controls. dims : napari.qt_dims.QtDims Dimension sliders; Qt View for Dims model. dockConsole : QtViewerDockWidget QWidget wrapped in a QDockWidget with forwarded viewer events. dockLayerControls : QtViewerDockWidget QWidget wrapped in a QDockWidget with forwarded viewer events. dockLayerList : QtViewerDockWidget QWidget wrapped in a QDockWidget with forwarded viewer events. layerButtons : QtLayerButtons Button controls for napari layers. layers : QtLayerList Qt view for LayerList controls. layer_to_visual : dict Dictionary mapping napari layers with their corresponding vispy_layers. view : vispy scene widget View displayed by vispy canvas. Adds a vispy ViewBox as a child widget. viewer : napari.components.ViewerModel Napari viewer containing the rendered scene, layers, and controls. viewerButtons : QtViewerButtons Button controls for the napari viewer. """ _instances = WeakSet() def __init__( self, viewer: ViewerModel, show_welcome_screen: bool = False ) -> None: super().__init__() self._instances.add(self) self.setAttribute(Qt.WidgetAttribute.WA_DeleteOnClose) self._show_welcome_screen = show_welcome_screen QCoreApplication.setAttribute( Qt.AA_UseStyleSheetPropagationInWidgetStyles, True ) self.viewer = viewer self.dims = QtDims(self.viewer.dims) self._controls = None self._layers = None self._layersButtons = None self._viewerButtons = None self._key_map_handler = KeymapHandler() self._key_map_handler.keymap_providers = [self.viewer] self._console_backlog = [] self._console = None self._dockLayerList = None self._dockLayerControls = None self._dockConsole = None self._dockPerformance = None # This dictionary holds the corresponding vispy visual for each layer self.layer_to_visual = {} self.overlay_to_visual = {} self._create_canvas() # Stacked widget to provide a welcome page self._welcome_widget = QtWidgetOverlay(self, self.canvas.native) self._welcome_widget.set_welcome_visible(show_welcome_screen) self._welcome_widget.sig_dropped.connect(self.dropEvent) self._welcome_widget.leave.connect(self._leave_canvas) self._welcome_widget.enter.connect(self._enter_canvas) main_widget = QWidget() main_layout = QVBoxLayout() main_layout.setContentsMargins(0, 2, 0, 2) main_layout.addWidget(self._welcome_widget) main_layout.addWidget(self.dims) main_layout.setSpacing(0) main_widget.setLayout(main_layout) self.setOrientation(Qt.Orientation.Vertical) self.addWidget(main_widget) self._cursors = { 'cross': Qt.CursorShape.CrossCursor, 'forbidden': Qt.CursorShape.ForbiddenCursor, 'pointing': Qt.CursorShape.PointingHandCursor, 'standard': Qt.CursorShape.ArrowCursor, } self._on_active_change() self._on_active_change ) self.setAcceptDrops(True) self.view = self.canvas.central_widget.add_view(border_width=0) = VispyCamera( self.view,, self.viewer.dims ) # Create the experimental QtPool for octree and/or monitor. self._qt_poll = _create_qt_poll(self, # Create the experimental RemoteManager for the monitor. self._remote_manager = _create_remote_manager( self.viewer.layers, self._qt_poll ) # moved from the old layerlist... still feels misplaced. # can you help me move this elsewhere? if config.async_loading: from napari._qt.experimental.qt_chunk_receiver import ( QtChunkReceiver, ) # The QtChunkReceiver object allows the ChunkLoader to pass newly # loaded chunks to the layers that requested them. self.chunk_receiver = QtChunkReceiver(self.layers) else: self.chunk_receiver = None # bind shortcuts stored in settings last. self._bind_shortcuts() settings = get_settings() self._update_dask_cache_settings(settings.application.dask) self._update_dask_cache_settings ) for layer in self.viewer.layers: self._add_layer(layer) for overlay in self.viewer._overlays.values(): self._add_overlay(overlay) @staticmethod def _update_dask_cache_settings( dask_setting: Union[DaskSettings, Event] = None ): """Update dask cache to match settings.""" if not dask_setting: return if not isinstance(dask_setting, DaskSettings): dask_setting = dask_setting.value enabled = dask_setting.enabled size = dask_setting.cache resize_dask_cache(int(int(enabled) * size * 1e9)) @property def controls(self) -> QtLayerControlsContainer: if self._controls is None: # Avoid circular import. from napari._qt.layer_controls import QtLayerControlsContainer self._controls = QtLayerControlsContainer(self.viewer) return self._controls @property def layers(self) -> QtLayerList: if self._layers is None: self._layers = QtLayerList(self.viewer.layers) return self._layers @property def layerButtons(self) -> QtLayerButtons: if self._layersButtons is None: self._layersButtons = QtLayerButtons(self.viewer) return self._layersButtons @property def viewerButtons(self) -> QtViewerButtons: if self._viewerButtons is None: self._viewerButtons = QtViewerButtons(self.viewer) return self._viewerButtons @property def dockLayerList(self) -> QtViewerDockWidget: if self._dockLayerList is None: layerList = QWidget() layerList.setObjectName('layerList') layerListLayout = QVBoxLayout() layerListLayout.addWidget(self.layerButtons) layerListLayout.addWidget(self.layers) layerListLayout.addWidget(self.viewerButtons) layerListLayout.setContentsMargins(8, 4, 8, 6) layerList.setLayout(layerListLayout) self._dockLayerList = QtViewerDockWidget( self, layerList, name=trans._('layer list'), area='left', allowed_areas=['left', 'right'], object_name='layer list', close_btn=False, ) return self._dockLayerList @property def dockLayerControls(self) -> QtViewerDockWidget: if self._dockLayerControls is None: self._dockLayerControls = QtViewerDockWidget( self, self.controls, name=trans._('layer controls'), area='left', allowed_areas=['left', 'right'], object_name='layer controls', close_btn=False, ) return self._dockLayerControls @property def dockConsole(self) -> QtViewerDockWidget: if self._dockConsole is None: self._dockConsole = QtViewerDockWidget( self, QWidget(), name=trans._('console'), area='bottom', allowed_areas=['top', 'bottom'], object_name='console', close_btn=False, ) self._dockConsole.setVisible(False) self._dockConsole.visibilityChanged.connect(self._ensure_connect) return self._dockConsole @property def dockPerformance(self) -> QtViewerDockWidget: if self._dockPerformance is None: self._dockPerformance = self._create_performance_dock_widget() return self._dockPerformance def _leave_canvas(self): """disable status on canvas leave""" self.viewer.status = "" self.viewer.mouse_over_canvas = False def _enter_canvas(self): """enable status on canvas enter""" self.viewer.status = "Ready" self.viewer.mouse_over_canvas = True def _ensure_connect(self): # lazy load console id(self.console) def _bind_shortcuts(self): """Bind shortcuts stored in SETTINGS to actions.""" for action, shortcuts in get_settings().shortcuts.shortcuts.items(): action_manager.unbind_shortcut(action) for shortcut in shortcuts: action_manager.bind_shortcut(action, shortcut) def _create_canvas(self) -> None: """Create the canvas and hook up events.""" self.canvas = VispyCanvas( keys=None, vsync=True, parent=self, size=self.viewer._canvas_size[::-1], autoswap=get_settings().experimental.autoswap_buffers, # see #5734 ) self.on_mouse_double_click ) self._key_map_handler.on_key_press ) self._key_map_handler.on_key_release ) self.canvas.bgcolor = transform_color( get_theme(self.viewer.theme, False).canvas.as_hex() )[0] theme = on_theme_change = self.canvas._on_theme_change theme.connect(on_theme_change) self.canvas.destroyed.connect(self._diconnect_theme) def _diconnect_theme(self): def _add_overlay(self, overlay: Overlay) -> None: vispy_overlay = create_vispy_overlay(overlay, viewer=self.viewer) if isinstance(overlay, CanvasOverlay): vispy_overlay.node.parent = self.view elif isinstance(overlay, SceneOverlay): vispy_overlay.node.parent = self.view.scene self.overlay_to_visual[overlay] = vispy_overlay def _create_performance_dock_widget(self): """Create the dock widget that shows performance metrics.""" if perf.USE_PERFMON: return QtViewerDockWidget( self, QtPerformance(), name=trans._('performance'), area='bottom', ) return None def _weakref_if_possible(self, obj): """Create a weakref to obj. Parameters ---------- obj : object Cannot create weakrefs to many Python built-in datatypes such as list, dict, str. From "Objects which support weak references include class instances, functions written in Python (but not in C), instance methods, sets, frozensets, some file objects, generators, type objects, sockets, arrays, deques, regular expression pattern objects, and code objects." Returns ------- weakref or object Returns a weakref if possible. """ try: newref = ref(obj) except TypeError: newref = obj return newref def _unwrap_if_weakref(self, value): """Return value or if that is weakref the object referenced by value. Parameters ---------- value : object or weakref No-op for types other than weakref. Returns ------- unwrapped: object or None Returns referenced object, or None if weakref is dead. """ unwrapped = value() if isinstance(value, ref) else value return unwrapped
[docs] def add_to_console_backlog(self, variables): """Save variables for pushing to console when it is instantiated. This function will create weakrefs when possible to avoid holding on to too much memory unnecessarily. Parameters ---------- variables : dict, str or list/tuple of str The variables to inject into the console's namespace. If a dict, a simple update is done. If a str, the string is assumed to have variable names separated by spaces. A list/tuple of str can also be used to give the variable names. If just the variable names are give (list/tuple/str) then the variable values looked up in the callers frame. """ if isinstance(variables, (str, list, tuple)): if isinstance(variables, str): vlist = variables.split() else: vlist = variables vdict = {} cf = sys._getframe(2) for name in vlist: try: vdict[name] = eval(name, cf.f_globals, cf.f_locals) except: # noqa: E722 print( f'Could not get variable {name} from ' f'{cf.f_code.co_name}' ) elif isinstance(variables, dict): vdict = variables else: raise TypeError('variables must be a dict/str/list/tuple') # weakly reference values if possible new_dict = {k: self._weakref_if_possible(v) for k, v in vdict.items()} self.console_backlog.append(new_dict)
@property def console_backlog(self): """List: items to push to console when instantiated.""" return self._console_backlog @property def console(self): """QtConsole: iPython console terminal integrated into the napari GUI.""" if self._console is None: try: from napari_console import QtConsole import napari with warnings.catch_warnings(): warnings.filterwarnings("ignore") self.console = QtConsole(self.viewer) self.console.push( {'napari': napari, 'action_manager': action_manager} ) for i in self.console_backlog: # recover weak refs self.console.push( { k: self._unwrap_if_weakref(v) for k, v in i.items() if self._unwrap_if_weakref(v) is not None } ) self._console_backlog = [] except ModuleNotFoundError: warnings.warn( trans._( 'napari-console not found. It can be installed with' ' "pip install napari_console"' ), stacklevel=1, ) self._console = None except ImportError: traceback.print_exc() warnings.warn( trans._( 'error importing napari-console. See console for full error.' ), stacklevel=1, ) self._console = None return self._console @console.setter def console(self, console): self._console = console if console is not None: self.dockConsole.setWidget(console) console.setParent(self.dockConsole) def _on_active_change(self): """When active layer changes change keymap handler.""" self._key_map_handler.keymap_providers = ( [self.viewer] if is None else [, self.viewer] ) def _on_add_layer_change(self, event): """When a layer is added, set its parent and order. Parameters ---------- event : napari.utils.event.Event The napari event that triggered this method. """ layer = event.value self._add_layer(layer) def _add_layer(self, layer): """When a layer is added, set its parent and order. Parameters ---------- layer : napari.layers.Layer Layer to be added. """ vispy_layer = create_vispy_layer(layer) # QtPoll is experimental. if self._qt_poll is not None: # QtPoll will call VipyBaseImage._on_poll() when the camera # moves or the timer goes off. # In the other direction, some visuals need to tell QtPoll to # start polling. When they receive new data they need to be # polled to load it, even if the camera is not moving. if is not None: vispy_layer.node.parent = self.view.scene self.layer_to_visual[layer] = vispy_layer # ensure correct canvas blending self._reorder_layers() def _remove_layer(self, event): """When a layer is removed, remove its parent. Parameters ---------- event : napari.utils.event.Event The napari event that triggered this method. """ layer = event.value vispy_layer = self.layer_to_visual[layer] vispy_layer.close() del vispy_layer del self.layer_to_visual[layer] self._reorder_layers() def _reorder_layers(self): """When the list is reordered, propagate changes to draw order.""" first_visible_found = False for i, layer in enumerate(self.viewer.layers): vispy_layer = self.layer_to_visual[layer] vispy_layer.order = i # the bottommost visible layer needs special treatment for blending if layer.visible and not first_visible_found: vispy_layer.first_visible = True first_visible_found = True else: vispy_layer.first_visible = False vispy_layer._on_blending_change() self.canvas._draw_order.clear() self.canvas.update() def _save_layers_dialog(self, selected=False): """Save layers (all or selected) to disk, using ````. Parameters ---------- selected : bool If True, only layers that are selected in the viewer will be saved. By default, all layers are saved. """ msg = '' if not len(self.viewer.layers): msg = trans._("There are no layers in the viewer to save") elif selected and not len(self.viewer.layers.selection): msg = trans._( 'Please select one or more layers to save,' '\nor use "Save all layers..."' ) if msg: raise OSError(trans._("Nothing to save")) # prepare list of extensions for drop down menu. ext_str, writers = _extension_string_for_layers( list(self.viewer.layers.selection) if selected else self.viewer.layers ) msg = trans._("selected") if selected else trans._("all") dlg = QFileDialog() hist = get_save_history() dlg.setHistory(hist) filename, selected_filter = dlg.getSaveFileName( self, # parent trans._('Save {msg} layers', msg=msg), # caption # home dir by default hist[0], # directory in PyQt, dir in PySide filter=ext_str, options=( QFileDialog.DontUseNativeDialog if in_ipython() else QFileDialog.Options() ), ) logging.debug( trans._( 'QFileDialog - filename: {filename} ' 'selected_filter: {selected_filter}', filename=filename or None, selected_filter=selected_filter or None, ) ) if filename: writer = _npe2_decode_selected_filter( ext_str, selected_filter, writers ) with warnings.catch_warnings(record=True) as wa: saved = filename, selected=selected, _writer=writer ) logging.debug('Saved %s', saved) error_messages = "\n".join(str(x.message.args[0]) for x in wa) if not saved: raise OSError( trans._( "File {filename} save failed.\n{error_messages}", deferred=True, filename=filename, error_messages=error_messages, ) ) update_save_history(saved[0]) def _update_welcome_screen(self): """Update welcome screen display based on layer count.""" if self._show_welcome_screen: self._welcome_widget.set_welcome_visible(not self.viewer.layers) def _screenshot(self, flash=True): """Capture a screenshot of the Vispy canvas. Parameters ---------- flash : bool Flag to indicate whether flash animation should be shown after the screenshot was captured. """ # CAN REMOVE THIS AFTER DEPRECATION IS DONE, see self.screenshot. img = self.canvas.native.grabFramebuffer() if flash: from napari._qt.utils import add_flash_animation # Here we are actually applying the effect to the `_welcome_widget` # and not # the `native` widget because it does not work on the # `native` widget. It's probably because the widget is in a stack # with the `QtWelcomeWidget`. add_flash_animation(self._welcome_widget) return img
[docs] def screenshot(self, path=None, flash=True): """Take currently displayed screen and convert to an image array. Parameters ---------- path : str Filename for saving screenshot image. flash : bool Flag to indicate whether flash animation should be shown after the screenshot was captured. Returns ------- image : array Numpy array of type ubyte and shape (h, w, 4). Index [0, 0] is the upper-left corner of the rendered region. """ img = QImg2array(self._screenshot(flash)) if path is not None: imsave(path, img) # scikit-image imsave method return img
[docs] def clipboard(self, flash=True): """Take a screenshot of the currently displayed screen and copy the image to the clipboard. Parameters ---------- flash : bool Flag to indicate whether flash animation should be shown after the screenshot was captured. """ cb = QGuiApplication.clipboard() cb.setImage(self._screenshot(flash))
def _screenshot_dialog(self): """Save screenshot of current display, default .png""" hist = get_save_history() dial = ScreenshotDialog(self.screenshot, self, hist[0], hist) if dial.exec_(): update_save_history(dial.selectedFiles()[0]) def _open_file_dialog_uni(self, caption: str) -> typing.List[str]: """ Open dialog to get list of files from user """ dlg = QFileDialog() hist = get_open_history() dlg.setHistory(hist) open_kwargs = { "parent": self, "caption": caption, } if "pyside" in QFileDialog.__module__.lower(): # PySide6 open_kwargs["dir"] = hist[0] else: open_kwargs["directory"] = hist[0] if in_ipython(): open_kwargs["options"] = QFileDialog.DontUseNativeDialog return dlg.getOpenFileNames(**open_kwargs)[0] def _open_files_dialog(self, choose_plugin=False): """Add files from the menubar.""" filenames = self._open_file_dialog_uni(trans._('Select file(s)...')) if (filenames != []) and (filenames is not None): for filename in filenames: self._qt_open( [filename], stack=False, choose_plugin=choose_plugin ) update_open_history(filenames[0]) def _open_files_dialog_as_stack_dialog(self, choose_plugin=False): """Add files as a stack, from the menubar.""" filenames = self._open_file_dialog_uni(trans._('Select files...')) if (filenames != []) and (filenames is not None): self._qt_open(filenames, stack=True, choose_plugin=choose_plugin) update_open_history(filenames[0]) def _open_folder_dialog(self, choose_plugin=False): """Add a folder of files from the menubar.""" dlg = QFileDialog() hist = get_open_history() dlg.setHistory(hist) folder = dlg.getExistingDirectory( self, trans._('Select folder...'), hist[0], # home dir by default ( QFileDialog.DontUseNativeDialog if in_ipython() else QFileDialog.Options() ), ) if folder not in {'', None}: self._qt_open([folder], stack=False, choose_plugin=choose_plugin) update_open_history(folder) def _qt_open( self, filenames: List[str], stack: Union[bool, List[List[str]]], choose_plugin: bool = False, plugin: str = None, layer_type: str = None, **kwargs, ): """Open files, potentially popping reader dialog for plugin selection. Call and catch errors that could be fixed by user making a plugin choice. Parameters ---------- filenames : List[str] paths to open choose_plugin : bool True if user wants to explicitly choose the plugin else False stack : bool or list[list[str]] whether to stack files or not. Can also be a list containing files to stack. plugin : str plugin to use for reading layer_type : str layer type for opened layers """ if choose_plugin: handle_gui_reading( filenames, self, stack, plugin_override=choose_plugin, **kwargs ) return try: filenames, stack=stack, plugin=plugin, layer_type=layer_type, **kwargs, ) except ReaderPluginError as e: handle_gui_reading( filenames, self, stack, e.reader_plugin, e, layer_type=layer_type, **kwargs, ) except MultipleReaderError: handle_gui_reading(filenames, self, stack, **kwargs) def _toggle_chunk_outlines(self): """Toggle whether we are drawing outlines around the chunks.""" from napari.layers.image.experimental.octree_image import ( _OctreeImageBase, ) for layer in self.viewer.layers: if isinstance(layer, _OctreeImageBase): layer.display.show_grid = not layer.display.show_grid def _on_cursor(self): """Set the appearance of the mouse cursor.""" cursor = if cursor in {'square', 'circle'}: # Scale size by zoom if needed size = self.viewer.cursor.size if self.viewer.cursor.scaled: size *= size = int(size) # make sure the square fits within the current canvas if size < 8 or size > (min(*self.canvas.size) - 4): q_cursor = self._cursors['cross'] elif cursor == 'circle': q_cursor = QCursor(circle_pixmap(size)) else: q_cursor = QCursor(square_pixmap(size)) elif cursor == 'crosshair': q_cursor = QCursor(crosshair_pixmap()) else: q_cursor = self._cursors[cursor] self.canvas.native.setCursor(q_cursor)
[docs] def toggle_console_visibility(self, event=None): """Toggle console visible and not visible. Imports the console the first time it is requested. """ if in_ipython() or in_jupyter(): return # force instantiation of console if not already instantiated _ = self.console viz = not self.dockConsole.isVisible() # modulate visibility at the dock widget level as console is dockable self.dockConsole.setVisible(viz) if self.dockConsole.isFloating(): self.dockConsole.setFloating(True) if viz: self.dockConsole.raise_() self.dockConsole.setFocus() self.viewerButtons.consoleButton.setProperty( 'expanded', self.dockConsole.isVisible() ) self.viewerButtons.consoleButton ) self.viewerButtons.consoleButton )
def _map_canvas2world(self, position): """Map position from canvas pixels into world coordinates. Parameters ---------- position : 2-tuple Position in canvas (x, y). Returns ------- coords : tuple Position in world coordinates, matches the total dimensionality of the viewer. """ nd = self.viewer.dims.ndisplay transform = self.view.scene.transform mapped_position = transform.imap(list(position))[:nd] position_world_slice = mapped_position[::-1] # handle position for 3D views of 2D data nd_point = len(self.viewer.dims.point) if nd_point < nd: position_world_slice = position_world_slice[-nd_point:] position_world = list(self.viewer.dims.point) for i, d in enumerate(self.viewer.dims.displayed): position_world[d] = position_world_slice[i] return tuple(position_world) @property def _canvas_corners_in_world(self): """Location of the corners of canvas in world coordinates. Returns ------- corners : 2-tuple Coordinates of top left and bottom right canvas pixel in the world. """ # Find corners of canvas in world coordinates top_left = self._map_canvas2world([0, 0]) bottom_right = self._map_canvas2world(self.canvas.size) return np.array([top_left, bottom_right])
[docs] def on_resize(self, event): """Called whenever canvas is resized. event : vispy.util.event.Event The vispy event that triggered this method. """ self.viewer._canvas_size = tuple(self.canvas.size[::-1])
def _process_mouse_event(self, mouse_callbacks, event): """Add properties to the mouse event before passing the event to the napari events system. Called whenever the mouse moves or is clicked. As such, care should be taken to reduce the overhead in this function. In future work, we should consider limiting the frequency at which it is called. This method adds following: position: the position of the click in world coordinates. view_direction: a unit vector giving the direction of the camera in world coordinates. up_direction: a unit vector giving the direction of the camera that is up in world coordinates. dims_displayed: a list of the dimensions currently being displayed in the viewer. This comes from viewer.dims.displayed. dims_point: the indices for the data in view in world coordinates. This comes from viewer.dims.point Parameters ---------- mouse_callbacks : function Mouse callbacks function. event : vispy.event.Event The vispy event that triggered this method. """ if event.pos is None: return # Add the view ray to the event event.view_direction = self.viewer.dims.ndim, self.viewer.dims.displayed ) event.up_direction = self.viewer.dims.ndim, self.viewer.dims.displayed ) # Update the cursor position self.viewer.cursor._view_direction = event.view_direction self.viewer.cursor.position = self._map_canvas2world(list(event.pos)) # Add the cursor position to the event event.position = self.viewer.cursor.position # Add the displayed dimensions to the event event.dims_displayed = list(self.viewer.dims.displayed) # Add the current dims indices event.dims_point = list(self.viewer.dims.point) # Put a read only wrapper on the event event = ReadOnlyWrapper(event, exceptions=('handled',)) mouse_callbacks(self.viewer, event) layer = if layer is not None: mouse_callbacks(layer, event)
[docs] def on_mouse_wheel(self, event): """Called whenever mouse wheel activated in canvas. Parameters ---------- event : vispy.event.Event The vispy event that triggered this method. """ self._process_mouse_event(mouse_wheel_callbacks, event)
[docs] def on_mouse_double_click(self, event): """Called whenever a mouse double-click happen on the canvas Parameters ---------- event : vispy.event.Event The vispy event that triggered this method. The `event.type` will always be `mouse_double_click` Notes ----- Note that this triggers in addition to the usual mouse press and mouse release. Therefore a double click from the user will likely triggers the following event in sequence: - mouse_press - mouse_release - mouse_double_click - mouse_release """ self._process_mouse_event(mouse_double_click_callbacks, event)
[docs] def on_mouse_press(self, event): """Called whenever mouse pressed in canvas. Parameters ---------- event : vispy.event.Event The vispy event that triggered this method. """ self._process_mouse_event(mouse_press_callbacks, event)
[docs] def on_mouse_move(self, event): """Called whenever mouse moves over canvas. Parameters ---------- event : vispy.event.Event The vispy event that triggered this method. """ self._process_mouse_event(mouse_move_callbacks, event)
[docs] def on_mouse_release(self, event): """Called whenever mouse released in canvas. Parameters ---------- event : vispy.event.Event The vispy event that triggered this method. """ self._process_mouse_event(mouse_release_callbacks, event)
[docs] def on_draw(self, event): """Called whenever the canvas is drawn. This is triggered from vispy whenever new data is sent to the canvas or the camera is moved and is connected in the `QtViewer`. """ # The canvas corners in full world coordinates (i.e. across all layers). canvas_corners_world = self._canvas_corners_in_world for layer in self.viewer.layers: # The following condition should mostly be False. One case when it can # be True is when a callback connected to # is executed before layer._slice_input has been updated by another callback # (e.g. when changing self.viewer.dims.ndisplay from 3 to 2). displayed_sorted = sorted(layer._slice_input.displayed) nd = len(displayed_sorted) if nd > self.viewer.dims.ndisplay: displayed_axes = displayed_sorted else: displayed_axes = self.viewer.dims.displayed[-nd:] layer._update_draw( scale_factor=1 /, corner_pixels_displayed=canvas_corners_world[ :, displayed_axes ], shape_threshold=self.canvas.size, )
[docs] def set_welcome_visible(self, visible): """Show welcome screen widget.""" self._show_welcome_screen = visible self._welcome_widget.set_welcome_visible(visible)
[docs] def keyPressEvent(self, event): """Called whenever a key is pressed. Parameters ---------- event : qtpy.QtCore.QEvent Event from the Qt context. """ self.canvas._backend._keyEvent(, event) event.accept()
[docs] def keyReleaseEvent(self, event): """Called whenever a key is released. Parameters ---------- event : qtpy.QtCore.QEvent Event from the Qt context. """ self.canvas._backend._keyEvent(, event) event.accept()
[docs] def dragEnterEvent(self, event): """Ignore event if not dragging & dropping a file or URL to open. Using event.ignore() here allows the event to pass through the parent widget to its child widget, otherwise the parent widget would catch the event and not pass it on to the child widget. Parameters ---------- event : qtpy.QtCore.QDragEvent Event from the Qt context. """ if event.mimeData().hasUrls(): self._set_drag_status() event.accept() else: event.ignore()
def _set_drag_status(self): """Set dedicated status message when dragging files into viewer""" self.viewer.status = trans._( 'Hold <Alt> key to open plugin selection. Hold <Shift> to open files as stack.' )
[docs] def dropEvent(self, event): """Add local files and web URLS with drag and drop. For each file, attempt to open with existing associated reader (if available). If no reader is associated or opening fails, and more than one reader is available, open dialog and ask user to choose among available readers. User can choose to persist this choice. Parameters ---------- event : qtpy.QtCore.QDropEvent Event from the Qt context. """ shift_down = ( QGuiApplication.keyboardModifiers() & Qt.KeyboardModifier.ShiftModifier ) alt_down = ( QGuiApplication.keyboardModifiers() & Qt.KeyboardModifier.AltModifier ) filenames = [] for url in event.mimeData().urls(): if url.isLocalFile(): # directories get a trailing "/", Path conversion removes it filenames.append(str(Path(url.toLocalFile()))) else: filenames.append(url.toString()) self._qt_open( filenames, stack=bool(shift_down), choose_plugin=bool(alt_down), )
[docs] def closeEvent(self, event): """Cleanup and close. Parameters ---------- event : qtpy.QtCore.QCloseEvent Event from the Qt context. """ self.layers.close() # if the viewer.QtDims object is playing an axis, we need to terminate # the AnimationThread before close, otherwise it will cause a segFault # or Abort trap. (calling stop() when no animation is occurring is also # not a problem) self.dims.stop() self.canvas.native.deleteLater() if self._console is not None: self.console.close() self.dockConsole.deleteLater() event.accept()
if TYPE_CHECKING: from napari._qt.experimental.qt_poll import QtPoll from napari.components.experimental.remote import RemoteManager def _create_qt_poll(parent: QObject, camera: Camera) -> Optional[QtPoll]: """Create and return a QtPoll instance, if needed. Create a QtPoll instance for octree or monitor. Octree needs QtPoll so VispyTiledImageLayer can finish in-progress loads even if the camera is not moving. Once loading is finish it will tell QtPoll it no longer needs to be polled. Monitor needs QtPoll to poll for incoming messages. This might be temporary until we can process incoming messages with a dedicated thread. Parameters ---------- parent : QObject Parent Qt object. camera : Camera Camera that the QtPoll object will listen to. Returns ------- Optional[QtPoll] The new QtPoll instance, if we need one. """ if not config.async_octree and not config.monitor: return None from napari._qt.experimental.qt_poll import QtPoll qt_poll = QtPoll(parent) return qt_poll def _create_remote_manager( layers: LayerList, qt_poll ) -> Optional[RemoteManager]: """Create and return a RemoteManager instance, if we need one. Parameters ---------- layers : LayersList The viewer's layers. qt_poll : QtPoll The viewer's QtPoll instance. """ if not config.monitor: return None # Not using the monitor at all from napari.components.experimental.monitor import monitor from napari.components.experimental.remote import RemoteManager # Start the monitor so we can access its events. The monitor has no # dependencies to napari except to utils.Event. started = monitor.start() if not started: return None # Probably not >= Python 3.9, so no manager is needed. # Create the remote manager and have monitor call its process_command() # method to execute commands from clients. manager = RemoteManager(layers) # RemoteManager will process incoming command from the monitor. monitor.run_command_event.connect(manager.process_command) # QtPoll should pool the RemoteManager and the Monitor. return manager