qpainter

I'm trying to draw a rectangle on GUI created by PyQt5 by drag and drop. I managed to do that, but the rectangle is drawn when the mouse left key is released. What I want to do is like this link : When the mouse left button is pressed, start drawing the rectangle. While dragging, adjust the rectangle shape with the mouse movement. When the mouse left button is released, determine the rectangle shape. How can I implement this? Thanks in advance. Here's my code. # -*- coding: utf-8 -*- import sys from PyQt5 import QtWidgets, QtCore from PyQt5.QtGui import QPainter class MyWidget(QtWidgets

Given a QPainterPath how can I stroke the path only on the inside or outside edge of the path (or left- or right-side for non-closed paths)? QPainter::strokePath() centers the pen along the path and causes the same amount of ink to fall on both sides. For a visual example of the desired effect, see this graphic I made (for an SVG proposal, not feature): I don't mind if this is done through some hack like setting the path itself as a clipping region (for inside) or anti-clipping region (for outside). The goal here is to fill a rounded rectangle with a low-opacity fill and then stroke just

This is what I tried, it gave me no output. Where am I going wrong? // Start point of bottom line qreal startPointX1 = 600.0; qreal startPointY1 = 600.0; // End point of bottom line qreal endPointX1 = 600.0; qreal endPointY1 = 1200.0; // Start point of top line qreal startPointX2 = 600.0; qreal startPointY2 = 600.0; // End point of top line qreal endPointX2 = 800.0; qreal endPointY2 = 1200.0; QPainterPath path; // Set pen to this point. path.moveTo (startPointX1, startPointY1); // Draw line from pen point to this point. path.lineTo (endPointX1, endPointY1); path.moveTo (endPointX1, endPointY1)

I have a PyQt4 program with widgets whose content redraws very slowly (it's ok, because of my tasks). And when I trying to resize those widgets, program is trying to redraw a lot of times while mouse is not released. That's a lot of freezes. I want to disable that auto-redrawing and configure PyQt to redraw all widgets only when mouse is released (which means that redraw happens exactly one time per one resize). How to do that? Edit1. I'll see it quite simply, like this: you drag the line, and while you dragging, all widgets stand. When you release it, widgets redrawing. But I'm really not

I'm trying to animate a polyline (it have to act like a wave). I've tried this way: from PySide.QtCore import * from PySide.QtGui import * import sys, time class Test(QMainWindow): def __init__(self, parent=None): QMainWindow.__init__(self, parent) def poly(self, pts): return QPolygonF(map(lambda p: QPointF(*p), pts)) def paintEvent(self, event): painter = QPainter(self) pts = [[80, 490], [180, 0], [280, 0], [430, 0], [580, 0], [680, 0], [780, 0]] for i in pts: while i[1] < 600: painter.setPen(QPen(QColor(Qt.darkGreen), 3)) painter.drawPolyline(self.poly(pts)) painter.setBrush(QBrush(QColor

In my application, I paint a street map using QPainter on a widget made by QPainterPaths that contain precalculated paths to be drawn the widget is currently a QWidget , not a QGLWidget , but this might change. I'm trying to move the painting off-screen and split it into chunked jobs I want to paint each chunk onto a QImage and finally draw all images onto the widget QPainterPaths are already chunked, so this is not the problem problem is, that drawing on QImages is about 5 times slower than drawing on QWidget Some benchmark testing I've done time values are rounded averages over multiple runs