Source code for pyqtgraph.widgets.RemoteGraphicsView

# -*- coding: utf-8 -*-
from ..Qt import QtGui, QtCore, QT_LIB
if QT_LIB.startswith('PyQt'):
    from ..Qt import sip
from .. import multiprocess as mp
from .GraphicsView import GraphicsView
from .. import CONFIG_OPTIONS
import mmap, tempfile, os, atexit, sys, random

__all__ = ['RemoteGraphicsView']

[docs]class RemoteGraphicsView(QtGui.QWidget): """ Replacement for GraphicsView that does all scene management and rendering on a remote process, while displaying on the local widget. GraphicsItems must be created by proxy to the remote process. """
[docs] def __init__(self, parent=None, *args, **kwds): """ The keyword arguments 'useOpenGL' and 'backgound', if specified, are passed to the remote GraphicsView.__init__(). All other keyword arguments are passed to multiprocess.QtProcess.__init__(). """ self._img = None self._imgReq = None self._sizeHint = (640,480) ## no clue why this is needed, but it seems to be the default sizeHint for GraphicsView. ## without it, the widget will not compete for space against another GraphicsView. QtGui.QWidget.__init__(self) # separate local keyword arguments from remote. remoteKwds = {} for kwd in ['useOpenGL', 'background']: if kwd in kwds: remoteKwds[kwd] = kwds.pop(kwd) self._proc = mp.QtProcess(**kwds) = self._proc._import('pyqtgraph')**CONFIG_OPTIONS) rpgRemote = self._proc._import('pyqtgraph.widgets.RemoteGraphicsView') self._view = rpgRemote.Renderer(*args, **remoteKwds) self._view._setProxyOptions(deferGetattr=True) self.setFocusPolicy(QtCore.Qt.FocusPolicy.StrongFocus) self.setSizePolicy(QtGui.QSizePolicy.Policy.Expanding, QtGui.QSizePolicy.Policy.Expanding) self.setMouseTracking(True) self.shm = None shmFileName = self._view.shmFileName() if sys.platform.startswith('win'): self.shmtag = shmFileName else: self.shmFile = open(shmFileName, 'r') self._view.sceneRendered.connect(mp.proxy(self.remoteSceneChanged)) #, callSync='off')) ## Note: we need synchronous signals ## even though there is no return value-- ## this informs the renderer that it is ## safe to begin rendering again. for method in ['scene', 'setCentralItem']: setattr(self, method, getattr(self._view, method))
def resizeEvent(self, ev): ret = super().resizeEvent(ev) self._view.resize(self.size(), _callSync='off') return ret def sizeHint(self): return QtCore.QSize(*self._sizeHint) def remoteSceneChanged(self, data): w, h, size, newfile = data #self._sizeHint = (whint, hhint) if self.shm is None or self.shm.size != size: if self.shm is not None: self.shm.close() if sys.platform.startswith('win'): self.shmtag = newfile ## on windows, we create a new tag for every resize self.shm = mmap.mmap(-1, size, self.shmtag) ## can't use tmpfile on windows because the file can only be opened once. else: self.shm = mmap.mmap(self.shmFile.fileno(), size, mmap.MAP_SHARED, mmap.PROT_READ) self._img = QtGui.QImage(self.shm, w, h, QtGui.QImage.Format.Format_RGB32).copy() self.update() def paintEvent(self, ev): if self._img is None: return p = QtGui.QPainter(self) p.drawImage(self.rect(), self._img, self._img.rect()) p.end() def serialize_mouse_enum(self, *args): # PyQt6 can pickle enums and flags but cannot cast to int # PyQt5 5.12, PyQt5 5.15, PySide2 5.15, PySide6 can pickle enums but not flags # PySide2 5.12 cannot pickle enums nor flags # MouseButtons and KeyboardModifiers are flags if QT_LIB != 'PyQt6': args = [int(x) for x in args] return args def serialize_mouse_event(self, ev): lpos = ev.position() if hasattr(ev, 'position') else ev.localPos() gpos = ev.globalPosition() if hasattr(ev, 'globalPosition') else ev.screenPos() typ, btn, btns, mods = self.serialize_mouse_enum( ev.type(), ev.button(), ev.buttons(), ev.modifiers()) return (typ, lpos, gpos, btn, btns, mods) def serialize_wheel_event(self, ev): # {PyQt6, PySide6} have position() # {PyQt5, PySide2} 5.15 have position() # {PyQt5, PySide2} 5.15 have posF() (contrary to C++ docs) # {PyQt5, PySide2} 5.12 have posF() lpos = ev.position() if hasattr(ev, 'position') else ev.posF() # gpos = ev.globalPosition() if hasattr(ev, 'globalPosition') else ev.globalPosF() gpos = lpos # RemoteGraphicsView Renderer assumes to be at (0, 0) btns, mods, phase = self.serialize_mouse_enum(ev.buttons(), ev.modifiers(), ev.phase()) return (lpos, gpos, ev.pixelDelta(), ev.angleDelta(), btns, mods, phase, ev.inverted()) def mousePressEvent(self, ev): self._view.mousePressEvent(self.serialize_mouse_event(ev), _callSync='off') ev.accept() return super().mousePressEvent(ev) def mouseReleaseEvent(self, ev): self._view.mouseReleaseEvent(self.serialize_mouse_event(ev), _callSync='off') ev.accept() return super().mouseReleaseEvent(ev) def mouseMoveEvent(self, ev): self._view.mouseMoveEvent(self.serialize_mouse_event(ev), _callSync='off') ev.accept() return super().mouseMoveEvent(ev) def wheelEvent(self, ev): self._view.wheelEvent(self.serialize_wheel_event(ev), _callSync='off') ev.accept() return super().wheelEvent(ev) def enterEvent(self, ev): lpos = ev.position() if hasattr(ev, 'position') else ev.localPos() wpos = ev.scenePosition() if hasattr(ev, 'scenePosition') else ev.windowPos() gpos = ev.globalPosition() if hasattr(ev, 'globalPosition') else ev.screenPos() lws = lpos, wpos, gpos self._view.enterEvent(lws, _callSync='off') return super().enterEvent(ev) def leaveEvent(self, ev): typ, = self.serialize_mouse_enum(ev.type()) self._view.leaveEvent(typ, _callSync='off') return super().leaveEvent(ev)
[docs] def remoteProcess(self): """Return the remote process handle. (see multiprocess.remoteproxy.RemoteEventHandler)""" return self._proc
[docs] def close(self): """Close the remote process. After this call, the widget will no longer be updated.""" self._view.sceneRendered.disconnect() self._proc.close()
class Renderer(GraphicsView): ## Created by the remote process to handle render requests sceneRendered = QtCore.Signal(object) def __init__(self, *args, **kwds): ## Create shared memory for rendered image #pg.dbg(namespace={'r': self}) if sys.platform.startswith('win'): self.shmtag = "pyqtgraph_shmem_" + ''.join([chr((random.getrandbits(20)%25) + 97) for i in range(20)]) self.shm = mmap.mmap(-1, mmap.PAGESIZE, self.shmtag) # use anonymous mmap on windows else: self.shmFile = tempfile.NamedTemporaryFile(prefix='pyqtgraph_shmem_') self.shmFile.write(b'\x00' * (mmap.PAGESIZE+1)) self.shmFile.flush() fd = self.shmFile.fileno() self.shm = mmap.mmap(fd, mmap.PAGESIZE, mmap.MAP_SHARED, mmap.PROT_WRITE) atexit.register(self.close) GraphicsView.__init__(self, *args, **kwds) self.scene().changed.connect(self.update) self.img = None self.renderTimer = QtCore.QTimer() self.renderTimer.timeout.connect(self.renderView) self.renderTimer.start(16) def close(self): self.shm.close() if not sys.platform.startswith('win'): self.shmFile.close() def shmFileName(self): if sys.platform.startswith('win'): return self.shmtag else: return def update(self): self.img = None return super().update() def resize(self, size): oldSize = self.size() super().resize(size) self.resizeEvent(QtGui.QResizeEvent(size, oldSize)) self.update() def renderView(self): if self.img is None: ## make sure shm is large enough and get its address if self.width() == 0 or self.height() == 0: return dpr = self.devicePixelRatioF() iwidth = int(self.width() * dpr) iheight = int(self.height() * dpr) size = iwidth * iheight * 4 if size > self.shm.size(): if sys.platform.startswith('win'): ## windows says "WindowsError: [Error 87] the parameter is incorrect" if we try to resize the mmap self.shm.close() ## it also says (sometimes) 'access is denied' if we try to reuse the tag. self.shmtag = "pyqtgraph_shmem_" + ''.join([chr((random.getrandbits(20)%25) + 97) for i in range(20)]) self.shm = mmap.mmap(-1, size, self.shmtag) elif sys.platform == 'darwin': self.shm.close() fd = self.shmFile.fileno() os.ftruncate(fd, size + 1) self.shm = mmap.mmap(fd, size, mmap.MAP_SHARED, mmap.PROT_WRITE) else: self.shm.resize(size) ## render the scene directly to shared memory # see for rationale if QT_LIB.startswith('PyQt'): # PyQt5, PyQt6 >= 6.0.1 img_ptr = int(sip.voidptr(self.shm)) else: # PySide2, PySide6 img_ptr = self.shm self.img = QtGui.QImage(img_ptr, iwidth, iheight, QtGui.QImage.Format.Format_RGB32) self.img.setDevicePixelRatio(dpr) self.img.fill(0xffffffff) p = QtGui.QPainter(self.img) self.render(p, self.viewRect(), self.rect()) p.end() self.sceneRendered.emit((iwidth, iheight, self.shm.size(), self.shmFileName())) def deserialize_mouse_event(self, mouse_event): typ, pos, gpos, btn, btns, mods = mouse_event typ = QtCore.QEvent.Type(typ) if QT_LIB != 'PyQt6': btn = QtCore.Qt.MouseButton(btn) btns = QtCore.Qt.MouseButtons(btns) mods = QtCore.Qt.KeyboardModifiers(mods) return QtGui.QMouseEvent(typ, pos, gpos, btn, btns, mods) def deserialize_wheel_event(self, wheel_event): pos, gpos, pixelDelta, angleDelta, btns, mods, phase, inverted = wheel_event if QT_LIB != 'PyQt6': btns = QtCore.Qt.MouseButtons(btns) mods = QtCore.Qt.KeyboardModifiers(mods) phase = QtCore.Qt.ScrollPhase(phase) return QtGui.QWheelEvent(pos, gpos, pixelDelta, angleDelta, btns, mods, phase, inverted) def mousePressEvent(self, mouse_event): ev = self.deserialize_mouse_event(mouse_event) return super().mousePressEvent(ev) def mouseMoveEvent(self, mouse_event): ev = self.deserialize_mouse_event(mouse_event) return super().mouseMoveEvent(ev) def mouseReleaseEvent(self, mouse_event): ev = self.deserialize_mouse_event(mouse_event) return super().mouseReleaseEvent(ev) def wheelEvent(self, wheel_event): ev = self.deserialize_wheel_event(wheel_event) return super().wheelEvent(ev) def enterEvent(self, lws): ev = QtGui.QEnterEvent(*lws) return super().enterEvent(ev) def leaveEvent(self, typ): typ = QtCore.QEvent.Type(typ) ev = QtCore.QEvent(typ) return super().leaveEvent(ev)