Re: [PyQt] Python wrappers for QML/ Qt Quick?
On Mon, Mar 8, 2010 at 4:50 PM, Attila Csipa p...@csipa.in.rs wrote: Note that QML itself will be part of mainline Qt4.7, so I guess it's just a question of time (read: Phil's schedule :) until a bit more 'official' support for QML + PyQt appears. There is a bit more to think about than just wrapping Qml* classes; there are multiple interesting paths for creating QML + Python apps. For one, it should be possible to avoid loading the PyQt libs altogether (in the interest of smaller footprint faster launch) - just create a C++ application like qmlviewer, and embed python interpreter to that. All the Qt facing code would be on the javascript side, and the javascript code would be able to access the embedded python interpreter through some exposed stubs. In the first phase, even being able to exec/eval strings would get you started. -- Ville M. Vainio http://tinyurl.com/vainio ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Using new-style connections with QSignalMapper
On Mon, 08 Mar 2010 17:29:48 -0500, Mark Visser ma...@lumierevfx.com wrote: Is there some reason new-style connection from any signal to QSignalMapper.map do not appear to work? Using old-style self.connect works, i.e.: | #self.connect(self.b1, SIGNAL(clicked()), # self.mapper, SLOT(map())) #self.connect(self.b2, SIGNAL(clicked()), # self.mapper, SLOT(map())) | But using new-style self.signal.connect does not: |||self.b1.clicked.connect(self.mapper.map) self.b2.clicked.connect(self.mapper.map) | Here's a complete example:| = from PyQt4.QtCore import * from PyQt4.QtGui import * app = QApplication([]) class Test(QWidget): def __init__(self, parent=None): super(Test, self).__init__(parent) layout = QVBoxLayout() self.b1 = QPushButton(B1) self.b2 = QPushButton(B2) layout.addWidget(self.b1) layout.addWidget(self.b2) self.setLayout(layout) self.mapper = QSignalMapper(self) self.mapper.setMapping(self.b1, B1) self.mapper.setMapping(self.b2, B2) self.b1.clicked.connect(self.mapper.map) self.b2.clicked.connect(self.mapper.map) #self.connect(self.b1, SIGNAL(clicked()), # self.mapper, SLOT(map())) #self.connect(self.b2, SIGNAL(clicked()), # self.mapper, SLOT(map())) self.mapper.mapped[QString].connect(self.sayIt) @pyqtSlot(QString) def sayIt(self, name): print name t = Test() t.show() app.exec_() ||=| It's actually a problem with QSignalMapper.map() being called from a proxy rather than new-style connections. The workaround is to explicitly specify a signal that is compatible with map()... self.b1.clicked[()].connect(self.mapper.map) Tonight's PyQt snapshot will be smarter about finding a usable Qt slot before deciding that it needs to use a proxy so that the workaround won't be necessary. Thanks, Phil ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Python wrappers for QML/ Qt Quick?
On Tue, Mar 9, 2010 at 2:07 PM, Giovanni Bajo ra...@develer.com wrote: It might make more sense to have a way to export PyQt classes to QML, that is implement QMLElement in Python rather than in C++, and make them available to QML itself. This is pretty much what I'm thinking of. Python would take the part of C++ here, not Javascript. -- Ville M. Vainio http://tinyurl.com/vainio ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
[PyQt] Best way to implement an Image Viewer?
I'm using Windows XP, Python 2.6.4, and PyQt 4.7.1. While trying out the example C:\Python26\Lib\site-packages\PyQt4\examples\widgets\imageviewer.pyw, I notice that the more I zoom into an 1553x2653 BW PNG image, the longer it takes to display. This becomes unacceptably long (on the order of a few seconds) at the not so high 3x zoom factor. Intuitively, I would have thought it would be *faster* since the more I zoom in the fewer image pixels need to be displayed. I think what's happening is the entire QLabel widget is getting enlarged then cropped, rather than just displaying a sub-portion of the image: def scaleImage(self, factor): self.scaleFactor *= factor self.imageLabel.resize(self.scaleFactor * self.imageLabel.pixmap().size()) I want to create an app to help people explore various image processing operations. Fast flexible image display is essential. Some features I like to have: * Zoom In/Out quickly. I can see zooming *out* being slower since more image pixels would be involved. Once past the 1x zoom-in factor, I'd rather have the pixels as raw as possible to avoid blurring edges like the Image Viewer example currently does. * Compare transformations by having multiple views of images that are synchronized as to pan position and zoom factor. Dragging the mouse in any of the views should pan all the views. * Multi-screen support. I started off by modifying the PyQt4 Image Viewer example, but now I'm having second thoughts. Should I really be basing my Image Viewer on a QLabel? Should I instead be using a QGraphicsView (even though I'll probably only have a single image, not lots of 2D objects)? Maybe I should use a QGLWidget (I'd rather not). Or perhaps I have to write my own custom widget and draw using a QPainter object? Any tips or pointers to other PyQt-based Image Viewers would be appreciated. ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Python wrappers for QML/ Qt Quick?
On 3/9/2010 11:37 AM, Ville M. Vainio wrote: On Mon, Mar 8, 2010 at 4:50 PM, Attila Csipap...@csipa.in.rs wrote: Note that QML itself will be part of mainline Qt4.7, so I guess it's just a question of time (read: Phil's schedule :) until a bit more 'official' support for QML + PyQt appears. There is a bit more to think about than just wrapping Qml* classes; there are multiple interesting paths for creating QML + Python apps. For one, it should be possible to avoid loading the PyQt libs altogether (in the interest of smaller footprint faster launch) - just create a C++ application like qmlviewer, and embed python interpreter to that. All the Qt facing code would be on the javascript side, and the javascript code would be able to access the embedded python interpreter through some exposed stubs. In the first phase, even being able to exec/eval strings would get you started. I personally don't see a good use case for putting Python somehow within QML. QML already comes with its scripting language and bindings (Javascript), so unless you are on a religion war, I don't see much sense in putting Python in there. It might make more sense to have a way to export PyQt classes to QML, that is implement QMLElement in Python rather than in C++, and make them available to QML itself. -- Giovanni Bajo Develer S.r.l. http://www.develer.com ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Best way to implement an Image Viewer?
TP a écrit : I'm using Windows XP, Python 2.6.4, and PyQt 4.7.1. While trying out the example C:\Python26\Lib\site-packages\PyQt4\examples\widgets\imageviewer.pyw, I notice that the more I zoom into an 1553x2653 BW PNG image, the longer it takes to display. This becomes unacceptably long (on the order of a few seconds) at the not so high 3x zoom factor. Intuitively, I would have thought it would be *faster* since the more I zoom in the fewer image pixels need to be displayed. I think what's happening is the entire QLabel widget is getting enlarged then cropped, rather than just displaying a sub-portion of the image: def scaleImage(self, factor): self.scaleFactor *= factor self.imageLabel.resize(self.scaleFactor * self.imageLabel.pixmap().size()) I want to create an app to help people explore various image processing operations. Fast flexible image display is essential. Some features I like to have: * Zoom In/Out quickly. I can see zooming *out* being slower since more image pixels would be involved. Once past the 1x zoom-in factor, I'd rather have the pixels as raw as possible to avoid blurring edges like the Image Viewer example currently does. * Compare transformations by having multiple views of images that are synchronized as to pan position and zoom factor. Dragging the mouse in any of the views should pan all the views. * Multi-screen support. I started off by modifying the PyQt4 Image Viewer example, but now I'm having second thoughts. Should I really be basing my Image Viewer on a QLabel? Should I instead be using a QGraphicsView (even though I'll probably only have a single image, not lots of 2D objects)? Maybe I should use a QGLWidget (I'd rather not). Or perhaps I have to write my own custom widget and draw using a QPainter object? Any tips or pointers to other PyQt-based Image Viewers would be appreciated. ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt See attachement, it's an images viewer + zoom with QGraphicScene. Before use, change the line 63 Vincent #!/usr/bin/env python # -*- coding: utf-8 -*- # Example of an image viewer with zoom # # Created: Thu Feb 25 19:54:49 2010 # by: PyQt4 UI code generator 4.4.4 # # Author: Vincent Vande Vyvre v...@swing.be # # Note: before use, change the line 63 import os import time import glob from PyQt4 import QtCore, QtGui class Ui_MainWindow(object): def setupUi(self, MainWindow): MainWindow.resize(900, 600) self.centralwidget = QtGui.QWidget(MainWindow) self.gridLayout = QtGui.QGridLayout(self.centralwidget) self.verticalLayout = QtGui.QVBoxLayout() self.scene = QtGui.QGraphicsScene() self.view = QtGui.QGraphicsView(self.scene) self.verticalLayout.addWidget(self.view) self.horizontalLayout = QtGui.QHBoxLayout() spacerItem = QtGui.QSpacerItem(150, 20, QtGui.QSizePolicy.Expanding, QtGui.QSizePolicy.Minimum) self.horizontalLayout.addItem(spacerItem) self.toolButton_3 = QtGui.QToolButton(self.centralwidget) self.toolButton_3.setIconSize(QtCore.QSize(48, 24)) self.toolButton_3.setText(Previous) self.horizontalLayout.addWidget(self.toolButton_3) self.toolButton_4 = QtGui.QToolButton(self.centralwidget) self.toolButton_4.setIconSize(QtCore.QSize(48, 24)) self.toolButton_4.setText(Next) self.horizontalLayout.addWidget(self.toolButton_4) spacerItem1 = QtGui.QSpacerItem(100, 20, QtGui.QSizePolicy.Expanding, QtGui.QSizePolicy.Minimum) self.horizontalLayout.addItem(spacerItem1) self.toolButton_6 = QtGui.QToolButton(self.centralwidget) self.toolButton_6.setText(Quit) self.horizontalLayout.addWidget(self.toolButton_6) self.verticalLayout.addLayout(self.horizontalLayout) self.gridLayout.addLayout(self.verticalLayout, 0, 0, 1, 1) MainWindow.setCentralWidget(self.centralwidget) MainWindow.setWindowTitle(speedyView) MainWindow.show() QtCore.QCoreApplication.processEvents() QtCore.QObject.connect(ui.toolButton_3, QtCore.SIGNAL(clicked()), self.prec) QtCore.QObject.connect(ui.toolButton_4, QtCore.SIGNAL(clicked()), self.next) QtCore.QObject.connect(ui.toolButton_6, QtCore.SIGNAL(clicked()), exit) QtCore.QMetaObject.connectSlotsByName(MainWindow) self.centralwidget.wheelEvent = self.wheel_event self.set_view() def set_view(self): in_folder = /folder/with/images/ chain = in_folder + /* self.images = glob.glob(chain) self.images.sort(cmp=lambda x, y: cmp(x.lower(), y.lower())) self.zoom_step = 0.04 self.w_vsize = self.view.size().width() self.h_vsize =
Re: [PyQt] Python wrappers for QML/ Qt Quick?
On Tuesday 09 March 2010 15:54:54 Ville M. Vainio wrote: On Tue, Mar 9, 2010 at 2:07 PM, Giovanni Bajo ra...@develer.com wrote: It might make more sense to have a way to export PyQt classes to QML, that is implement QMLElement in Python rather than in C++, and make them available to QML itself. This is pretty much what I'm thinking of. Python would take the part of C++ here, not Javascript. If I understand correctly what you want to do, it has little to do with PyQt, it would be more of a PyQML custom binding... Which is interesting, but sounds like quite a niche to me - it will be hard to avoid Qt parts, and at that point it's much easier to go via the 'main' PyQt path. But, I'm no QML expert (yet :), so take this with a grain of salt, I don't intend to discourage anyone. What might be related, but I also don't know enough about, is what the current state of QtScript is. Is currently it possible to operate on Python objects from QtScript ? 'Cause if it is, QML should not be far off. Regards, Attila ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Python wrappers for QML/ Qt Quick?
On Tue, 2010-03-09 at 19:57 +0100, Attila Csipa wrote: On Tuesday 09 March 2010 15:54:54 Ville M. Vainio wrote: On Tue, Mar 9, 2010 at 2:07 PM, Giovanni Bajo ra...@develer.com wrote: It might make more sense to have a way to export PyQt classes to QML, that is implement QMLElement in Python rather than in C++, and make them available to QML itself. This is pretty much what I'm thinking of. Python would take the part of C++ here, not Javascript. If I understand correctly what you want to do, it has little to do with PyQt, it would be more of a PyQML custom binding... Which is interesting, but sounds like quite a niche to me - it will be hard to avoid Qt parts, and at that point it's much easier to go via the 'main' PyQt path. But, I'm no QML expert (yet :), so take this with a grain of salt, I don't intend to discourage anyone. What might be related, but I also don't know enough about, is what the current state of QtScript is. Is currently it possible to operate on Python objects from QtScript ? 'Cause if it is, QML should not be far off. Your two examples are unrelated. QtScript creates an automatic binding between Javascript and C++ using QObject introspection features. Thus, if you create a Python QObject, explicitly define signals/slots/properties at the QMetaObject level through PyQt decorators, the resulting object will be accessible from QtScript, with QtScript totally ignoring it is a Python object under the hood. For a C++ object to be exported to QML, on the other hand, you need an additional set of meta-definitions which are currently unavailable from Python. I'm not even sure if those meta-definitions resolves to *runtime* data that can be dynamically build, as it would be required by PyQt. Surely, there is more work to be done on the PyQt side. -- Giovanni Bajo Develer S.r.l. http://www.develer.com ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
[PyQt] Style sheet properties..
Hello all, If i apply a property to a parent widget it is automatically applied for child widgets too.. Is there any way of preventing this?? For example if i set background color as white in a dialog then any button,combo boxes and scroll bars(within the dialog) looks white and it lacks it's native look(have to say it's unpleasant to the eyes(esp. in unix) ugly).. Is there any way that i can apply the stylesheets only to a parent widget not to it's children? can i exclude specifically some child widgets from not inheriting parent SS properties?? ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] VTK in PyQt
Gib Bogle wrote: Gib Bogle wrote: OK, I located QVTKRenderWindowInteractor.py. I'll see if I can figure out how to use it. Not much success here. Maybe you want to check the source code of http://sourceforge.net/projects/pymbs/ Its a python Multibody modelling tool width some visualization facilities based on qt4 and VTK. (in the 'Graphics' package) Regards, Bastian. ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] QTreeWidget setItemWidget dissapears after drag drop
Any idea how to keep the setItemWidget() after it's reparented ? ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] VTK in PyQt
I looked through the code and two things I see different than what I have: a. I set the size of my RenderWindow b. I keep a reference to it, which probably isn't your problem because your not getting a seg fault. I've got an example but I can't verify that it works since I don't have vtk installed atm. mbs ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Best way to implement an Image Viewer?
TP a crit: On Tue, Mar 9, 2010 at 3:54 PM, TP wing...@gmail.com wrote: On Tue, Mar 9, 2010 at 9:27 AM, Vincent Vande Vyvre vincent.vandevy...@swing.be wrote: TP a crit : I'm using Windows XP, Python 2.6.4, and PyQt 4.7.1. While trying out the example C:\Python26\Lib\site-packages\PyQt4\examples\widgets\imageviewer.pyw, I notice that the more I zoom into an 1553x2653 BW PNG image, the longer it takes to display. This becomes unacceptably long (on the order of a few seconds) at the not so high 3x zoom factor. Intuitively, I would have thought it would be *faster* since the more I zoom in the fewer image pixels need to be displayed. I think what's happening is the entire QLabel widget is getting enlarged then cropped, rather than just displaying a sub-portion of the image: def scaleImage(self, factor): self.scaleFactor *= factor self.imageLabel.resize(self.scaleFactor * self.imageLabel.pixmap().size()) I want to create an app to help people explore various image processing operations. Fast flexible image display is essential. Some features I like to have: * Zoom In/Out quickly. I can see zooming *out* being slower since more image pixels would be involved. Once past the 1x zoom-in factor, I'd rather have the pixels as raw as possible to avoid blurring edges like the Image Viewer example currently does. * Compare transformations by having multiple views of images that are synchronized as to pan position and zoom factor. Dragging the mouse in any of the views should pan all the views. * Multi-screen support. I started off by modifying the PyQt4 Image Viewer example, but now I'm having second thoughts. Should I really be basing my Image Viewer on a QLabel? Should I instead be using a QGraphicsView (even though I'll probably only have a single image, not lots of 2D objects)? Maybe I should use a QGLWidget (I'd rather not). Or perhaps I have to write my own custom widget and draw using a QPainter object? Any tips or pointers to other PyQt-based Image Viewers would be appreciated. ___ PyQt mailing list PyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt See attachement, it's an images viewer + zoom with QGraphicScene. Before use, change the line 63 Vincent ___ PyQt mailing list PyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt Thank you. Your example does indeed zoom in/out quickly. However, delving into it I see it basically doing something like this: scaledPixmap = pixmap.scaled(newWidth, newHeight, QtCore.Qt.KeepAspectRatio, QtCore.Qt.FastTransformation) self.scene.clear() self.scene.setSceneRect(0, 0, newWidth, newHeight) self.scene.addPixmap(scaledPixmap) And if I change QtCore.Qt.FastTransformation to QtCore.Qt.SmoothTransformation things become as slow as using a QLabel. It seems to me that doing things this way completely ignores the advantage of using a QGraphicsScene? Instead of scaling (and therefore recreating the Pixmap), one should presumably use the QGraphicsScene scale() and translate() methods. Anyway, my original question remains. Is the best approach to use a QGraphicsView or one of the other options previously mentioned? Yes, it is ...for me Ooops. I meant to say: Instead of scaling (and therefore recreating the Pixmap), one should presumably use the QGraphicsView scale() and translate() methods. If you resize the current view the degradation is exponantial. If you like mosaics ... It's necessary to re-create the view from the original for each step of zoom. For your second idea, you can change the function like this: def zoom(self, step): w = (1 + self.zoom_step*step) self.view.scale(w, w) and see the result. All the areas with hight contrast are in staircase. I don't say my method is the best way, but is a good compromise between speed and quality. Vincent ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
