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Attribute Error while using PyQtgraph libraries in my python code

I'm running a code from github site and it has this error ( last lines) :
File "D:\Anaconda3\lib\site-packages\pyqtgraph\opengl\GLViewWidget.py", line 152, in viewMatrix
tr.translate(-center.x(), -center.y(), -center.z())
AttributeError: 'int' object has no attribute 'x'
I found that the error is related to pyqtgraph libraries and i didn't change their files
just install the last versions of PyOpenGl and PyQtGraph in spyder
can you please help me in this error?

We need more information,
The problem seems to be related to the fact that center is an int but you use it as an object with attributs
Can we see center's initialization ?

the GlViewWidget.py file :
from ..Qt import QtCore, QtGui, QtOpenGL, QT_LIB
from OpenGL.GL import *
import OpenGL.GL.framebufferobjects as glfbo
import numpy as np
from .. import Vector
from .. import functions as fn
##Vector = QtGui.QVector3D
ShareWidget = None
class GLViewWidget(QtOpenGL.QGLWidget):
"""
Basic widget for displaying 3D data
- Rotation/scale controls
- Axis/grid display
- Export options
High-DPI displays: Qt5 should automatically detect the correct resolution.
For Qt4, specify the ``devicePixelRatio`` argument when initializing the
widget (usually this value is 1-2).
"""
def __init__(self, parent=None, devicePixelRatio=None):
global ShareWidget
if ShareWidget is None:
## create a dummy widget to allow sharing objects (textures, shaders, etc) between views
ShareWidget = QtOpenGL.QGLWidget()
QtOpenGL.QGLWidget.__init__(self, parent, ShareWidget)
self.setFocusPolicy(QtCore.Qt.ClickFocus)
self.opts = {
'center': Vector(0,0,0), ## will always appear at the center of the widget
'distance': 10.0, ## distance of camera from center
'fov': 60, ## horizontal field of view in degrees
'elevation': 30, ## camera's angle of elevation in degrees
'azimuth': 45, ## camera's azimuthal angle in degrees
## (rotation around z-axis 0 points along x-axis)
'viewport': None, ## glViewport params; None == whole widget
'devicePixelRatio': devicePixelRatio,
}
self.setBackgroundColor('k')
self.items = []
self.noRepeatKeys = [QtCore.Qt.Key_Right, QtCore.Qt.Key_Left, QtCore.Qt.Key_Up, QtCore.Qt.Key_Down, QtCore.Qt.Key_PageUp, QtCore.Qt.Key_PageDown]
self.keysPressed = {}
self.keyTimer = QtCore.QTimer()
self.keyTimer.timeout.connect(self.evalKeyState)
self.makeCurrent()
def addItem(self, item):
self.items.append(item)
if hasattr(item, 'initializeGL'):
self.makeCurrent()
try:
item.initializeGL()
except:
self.checkOpenGLVersion('Error while adding item %s to GLViewWidget.' % str(item))
item._setView(self)
#print "set view", item, self, item.view()
self.update()
def removeItem(self, item):
self.items.remove(item)
item._setView(None)
self.update()
def initializeGL(self):
self.resizeGL(self.width(), self.height())
def setBackgroundColor(self, *args, **kwds):
"""
Set the background color of the widget. Accepts the same arguments as
pg.mkColor() and pg.glColor().
"""
self.opts['bgcolor'] = fn.glColor(*args, **kwds)
self.update()
def getViewport(self):
vp = self.opts['viewport']
dpr = self.devicePixelRatio()
if vp is None:
return (0, 0, int(self.width() * dpr), int(self.height() * dpr))
else:
return tuple([int(x * dpr) for x in vp])
def devicePixelRatio(self):
dpr = self.opts['devicePixelRatio']
if dpr is not None:
return dpr
if hasattr(QtOpenGL.QGLWidget, 'devicePixelRatio'):
return QtOpenGL.QGLWidget.devicePixelRatio(self)
else:
return 1.0
def resizeGL(self, w, h):
pass
#glViewport(*self.getViewport())
#self.update()
def setProjection(self, region=None):
m = self.projectionMatrix(region)
glMatrixMode(GL_PROJECTION)
glLoadIdentity()
a = np.array(m.copyDataTo()).reshape((4,4))
glMultMatrixf(a.transpose())
def projectionMatrix(self, region=None):
if region is None:
dpr = self.devicePixelRatio()
region = (0, 0, self.width() * dpr, self.height() * dpr)
x0, y0, w, h = self.getViewport()
dist = self.opts['distance']
fov = self.opts['fov']
nearClip = dist * 0.001
farClip = dist * 1000.
r = nearClip * np.tan(fov * 0.5 * np.pi / 180.)
t = r * h / w
## Note that X0 and width in these equations must be the values used in viewport
left = r * ((region[0]-x0) * (2.0/w) - 1)
right = r * ((region[0]+region[2]-x0) * (2.0/w) - 1)
bottom = t * ((region[1]-y0) * (2.0/h) - 1)
top = t * ((region[1]+region[3]-y0) * (2.0/h) - 1)
tr = QtGui.QMatrix4x4()
tr.frustum(left, right, bottom, top, nearClip, farClip)
return tr
def setModelview(self):
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
m = self.viewMatrix()
a = np.array(m.copyDataTo()).reshape((4,4))
glMultMatrixf(a.transpose())
def viewMatrix(self):
tr = QtGui.QMatrix4x4()
tr.translate( 0.0, 0.0, -self.opts['distance'])
tr.rotate(self.opts['elevation']-90, 1, 0, 0)
tr.rotate(self.opts['azimuth']+90, 0, 0, -1)
center = self.opts['center']
tr.translate(-center.x(), -center.y(), -center.z())
return tr
def itemsAt(self, region=None):
"""
Return a list of the items displayed in the region (x, y, w, h)
relative to the widget.
"""
region = (region[0], self.height()-(region[1]+region[3]), region[2], region[3])
#buf = np.zeros(100000, dtype=np.uint)
buf = glSelectBuffer(100000)
try:
glRenderMode(GL_SELECT)
glInitNames()
glPushName(0)
self._itemNames = {}
self.paintGL(region=region, useItemNames=True)
finally:
hits = glRenderMode(GL_RENDER)
items = [(h.near, h.names[0]) for h in hits]
items.sort(key=lambda i: i[0])
return [self._itemNames[i[1]] for i in items]
def paintGL(self, region=None, viewport=None, useItemNames=False):
"""
viewport specifies the arguments to glViewport. If None, then we use self.opts['viewport']
region specifies the sub-region of self.opts['viewport'] that should be rendered.
Note that we may use viewport != self.opts['viewport'] when exporting.
"""
if viewport is None:
glViewport(*self.getViewport())
else:
glViewport(*viewport)
self.setProjection(region=region)
self.setModelview()
bgcolor = self.opts['bgcolor']
glClearColor(*bgcolor)
glClear( GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT )
self.drawItemTree(useItemNames=useItemNames)
def drawItemTree(self, item=None, useItemNames=False):
if item is None:
items = [x for x in self.items if x.parentItem() is None]
else:
items = item.childItems()
items.append(item)
items.sort(key=lambda a: a.depthValue())
for i in items:
if not i.visible():
continue
if i is item:
try:
glPushAttrib(GL_ALL_ATTRIB_BITS)
if useItemNames:
glLoadName(i._id)
self._itemNames[i._id] = i
i.paint()
except:
from .. import debug
debug.printExc()
msg = "Error while drawing item %s." % str(item)
ver = glGetString(GL_VERSION)
if ver is not None:
ver = ver.split()[0]
if int(ver.split(b'.')[0]) < 2:
print(msg + " The original exception is printed above; however, pyqtgraph requires OpenGL version 2.0 or greater for many of its 3D features and your OpenGL version is %s. Installing updated display drivers may resolve this issue." % ver)
else:
print(msg)
finally:
glPopAttrib()
else:
glMatrixMode(GL_MODELVIEW)
glPushMatrix()
try:
tr = i.transform()
a = np.array(tr.copyDataTo()).reshape((4,4))
glMultMatrixf(a.transpose())
self.drawItemTree(i, useItemNames=useItemNames)
finally:
glMatrixMode(GL_MODELVIEW)
glPopMatrix()
def setCameraPosition(self, pos=None, distance=None, elevation=None, azimuth=None):
if pos is not None:
self.opts['center'] = pos
if distance is not None:
self.opts['distance'] = distance
if elevation is not None:
self.opts['elevation'] = elevation
if azimuth is not None:
self.opts['azimuth'] = azimuth
self.update()
def cameraPosition(self):
"""Return current position of camera based on center, dist, elevation, and azimuth"""
center = self.opts['center']
dist = self.opts['distance']
elev = self.opts['elevation'] * np.pi/180.
azim = self.opts['azimuth'] * np.pi/180.
pos = Vector(
center.x() + dist * np.cos(elev) * np.cos(azim),
center.y() + dist * np.cos(elev) * np.sin(azim),
center.z() + dist * np.sin(elev)
)
return pos
def orbit(self, azim, elev):
"""Orbits the camera around the center position. *azim* and *elev* are given in degrees."""
self.opts['azimuth'] += azim
self.opts['elevation'] = np.clip(self.opts['elevation'] + elev, -90, 90)
self.update()
def pan(self, dx, dy, dz, relative='global'):
"""
Moves the center (look-at) position while holding the camera in place.
============== =======================================================
**Arguments:**
*dx* Distance to pan in x direction
*dy* Distance to pan in y direction
*dx* Distance to pan in z direction
*relative* String that determines the direction of dx,dy,dz.
If "global", then the global coordinate system is used.
If "view", then the z axis is aligned with the view
direction, and x and y axes are inthe plane of the
view: +x points right, +y points up.
If "view-upright", then x is in the global xy plane and
points to the right side of the view, y is in the
global xy plane and orthogonal to x, and z points in
the global z direction.
============== =======================================================
Distances are scaled roughly such that a value of 1.0 moves
by one pixel on screen.
Prior to version 0.11, *relative* was expected to be either True (x-aligned) or
False (global). These values are deprecated but still recognized.
"""
# for backward compatibility:
relative = {True: "view-upright", False: "global"}.get(relative, relative)
if relative == 'global':
self.opts['center'] += QtGui.QVector3D(dx, dy, dz)
elif relative == 'view-upright':
cPos = self.cameraPosition()
cVec = self.opts['center'] - cPos
dist = cVec.length() ## distance from camera to center
xDist = dist * 2. * np.tan(0.5 * self.opts['fov'] * np.pi / 180.) ## approx. width of view at distance of center point
xScale = xDist / self.width()
zVec = QtGui.QVector3D(0,0,1)
xVec = QtGui.QVector3D.crossProduct(zVec, cVec).normalized()
yVec = QtGui.QVector3D.crossProduct(xVec, zVec).normalized()
self.opts['center'] = self.opts['center'] + xVec * xScale * dx + yVec * xScale * dy + zVec * xScale * dz
elif relative == 'view':
# pan in plane of camera
elev = np.radians(self.opts['elevation'])
azim = np.radians(self.opts['azimuth'])
fov = np.radians(self.opts['fov'])
dist = (self.opts['center'] - self.cameraPosition()).length()
fov_factor = np.tan(fov / 2) * 2
scale_factor = dist * fov_factor / self.width()
z = scale_factor * np.cos(elev) * dy
x = scale_factor * (np.sin(azim) * dx - np.sin(elev) * np.cos(azim) * dy)
y = scale_factor * (np.cos(azim) * dx + np.sin(elev) * np.sin(azim) * dy)
self.opts['center'] += QtGui.QVector3D(x, -y, z)
else:
raise ValueError("relative argument must be global, view, or view-upright")
self.update()
def pixelSize(self, pos):
"""
Return the approximate size of a screen pixel at the location pos
Pos may be a Vector or an (N,3) array of locations
"""
cam = self.cameraPosition()
if isinstance(pos, np.ndarray):
cam = np.array(cam).reshape((1,)*(pos.ndim-1)+(3,))
dist = ((pos-cam)**2).sum(axis=-1)**0.5
else:
dist = (pos-cam).length()
xDist = dist * 2. * np.tan(0.5 * self.opts['fov'] * np.pi / 180.)
return xDist / self.width()
def mousePressEvent(self, ev):
self.mousePos = ev.pos()
def mouseMoveEvent(self, ev):
diff = ev.pos() - self.mousePos
self.mousePos = ev.pos()
if ev.buttons() == QtCore.Qt.LeftButton:
if (ev.modifiers() & QtCore.Qt.ControlModifier):
self.pan(diff.x(), diff.y(), 0, relative='view')
else:
self.orbit(-diff.x(), diff.y())
elif ev.buttons() == QtCore.Qt.MidButton:
if (ev.modifiers() & QtCore.Qt.ControlModifier):
self.pan(diff.x(), 0, diff.y(), relative='view-upright')
else:
self.pan(diff.x(), diff.y(), 0, relative='view-upright')
def mouseReleaseEvent(self, ev):
pass
# Example item selection code:
#region = (ev.pos().x()-5, ev.pos().y()-5, 10, 10)
#print(self.itemsAt(region))
## debugging code: draw the picking region
#glViewport(*self.getViewport())
#glClear( GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT )
#region = (region[0], self.height()-(region[1]+region[3]), region[2], region[3])
#self.paintGL(region=region)
#self.swapBuffers()
def wheelEvent(self, ev):
delta = 0
if QT_LIB in ['PyQt4', 'PySide']:
delta = ev.delta()
else:
delta = ev.angleDelta().x()
if delta == 0:
delta = ev.angleDelta().y()
if (ev.modifiers() & QtCore.Qt.ControlModifier):
self.opts['fov'] *= 0.999**delta
else:
self.opts['distance'] *= 0.999**delta
self.update()
def keyPressEvent(self, ev):
if ev.key() in self.noRepeatKeys:
ev.accept()
if ev.isAutoRepeat():
return
self.keysPressed[ev.key()] = 1
self.evalKeyState()
def keyReleaseEvent(self, ev):
if ev.key() in self.noRepeatKeys:
ev.accept()
if ev.isAutoRepeat():
return
try:
del self.keysPressed[ev.key()]
except:
self.keysPressed = {}
self.evalKeyState()
def evalKeyState(self):
speed = 2.0
if len(self.keysPressed) > 0:
for key in self.keysPressed:
if key == QtCore.Qt.Key_Right:
self.orbit(azim=-speed, elev=0)
elif key == QtCore.Qt.Key_Left:
self.orbit(azim=speed, elev=0)
elif key == QtCore.Qt.Key_Up:
self.orbit(azim=0, elev=-speed)
elif key == QtCore.Qt.Key_Down:
self.orbit(azim=0, elev=speed)
elif key == QtCore.Qt.Key_PageUp:
pass
elif key == QtCore.Qt.Key_PageDown:
pass
self.keyTimer.start(16)
else:
self.keyTimer.stop()
def checkOpenGLVersion(self, msg):
## Only to be called from within exception handler.
ver = glGetString(GL_VERSION).split()[0]
if int(ver.split(b'.')[0]) < 2:
from .. import debug
debug.printExc()
raise Exception(msg + " The original exception is printed above; however, pyqtgraph requires OpenGL version 2.0 or greater for many of its 3D features and your OpenGL version is %s. Installing updated display drivers may resolve this issue." % ver)
else:
raise
def readQImage(self):
"""
Read the current buffer pixels out as a QImage.
"""
w = self.width()
h = self.height()
self.repaint()
pixels = np.empty((h, w, 4), dtype=np.ubyte)
pixels[:] = 128
pixels[...,0] = 50
pixels[...,3] = 255
glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, pixels)
# swap B,R channels for Qt
tmp = pixels[...,0].copy()
pixels[...,0] = pixels[...,2]
pixels[...,2] = tmp
pixels = pixels[::-1] # flip vertical
img = fn.makeQImage(pixels, transpose=False)
return img
def renderToArray(self, size, format=GL_BGRA, type=GL_UNSIGNED_BYTE, textureSize=1024, padding=256):
w,h = map(int, size)
self.makeCurrent()
tex = None
fb = None
try:
output = np.empty((w, h, 4), dtype=np.ubyte)
fb = glfbo.glGenFramebuffers(1)
glfbo.glBindFramebuffer(glfbo.GL_FRAMEBUFFER, fb )
glEnable(GL_TEXTURE_2D)
tex = glGenTextures(1)
glBindTexture(GL_TEXTURE_2D, tex)
texwidth = textureSize
data = np.zeros((texwidth,texwidth,4), dtype=np.ubyte)
## Test texture dimensions first
glTexImage2D(GL_PROXY_TEXTURE_2D, 0, GL_RGBA, texwidth, texwidth, 0, GL_RGBA, GL_UNSIGNED_BYTE, None)
if glGetTexLevelParameteriv(GL_PROXY_TEXTURE_2D, 0, GL_TEXTURE_WIDTH) == 0:
raise Exception("OpenGL failed to create 2D texture (%dx%d); too large for this hardware." % shape[:2])
## create teture
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texwidth, texwidth, 0, GL_RGBA, GL_UNSIGNED_BYTE, data.transpose((1,0,2)))
self.opts['viewport'] = (0, 0, w, h) # viewport is the complete image; this ensures that paintGL(region=...)
# is interpreted correctly.
p2 = 2 * padding
for x in range(-padding, w-padding, texwidth-p2):
for y in range(-padding, h-padding, texwidth-p2):
x2 = min(x+texwidth, w+padding)
y2 = min(y+texwidth, h+padding)
w2 = x2-x
h2 = y2-y
## render to texture
glfbo.glFramebufferTexture2D(glfbo.GL_FRAMEBUFFER, glfbo.GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex, 0)
self.paintGL(region=(x, h-y-h2, w2, h2), viewport=(0, 0, w2, h2)) # only render sub-region
glBindTexture(GL_TEXTURE_2D, tex) # fixes issue #366
## read texture back to array
data = glGetTexImage(GL_TEXTURE_2D, 0, format, type)
data = np.fromstring(data, dtype=np.ubyte).reshape(texwidth,texwidth,4).transpose(1,0,2)[:, ::-1]
output[x+padding:x2-padding, y+padding:y2-padding] = data[padding:w2-padding, -(h2-padding):-padding]
finally:
self.opts['viewport'] = None
glfbo.glBindFramebuffer(glfbo.GL_FRAMEBUFFER, 0)
glBindTexture(GL_TEXTURE_2D, 0)
if tex is not None:
glDeleteTextures([tex])
if fb is not None:
glfbo.glDeleteFramebuffers([fb])
return output

Somewhere in your code you are setting the center to be an int. setCameraPosition, maybe? It needs to be a Vector object, instead.

Animate algorithm

I want to visualize an algorithm (Graham scan) in python with tkinter.
I want to animate the algorithm and I am stuck.
I basically want to draw and delete lines but I don't understand canvas.after() well enough to make it work.
draw_line() returns the line object but when I call it in canvas.after(..., draw_line, ...) I don't see a way to get the return value or how to call another canvas.after() to change the color/delete that line if the function draw_line() hasn't been called yet because of the delay.
Thanks in advance.
from tkinter import *
import math
import random
class Point:
def __init__(self, _x, _y, _a=0):
self.x = _x
self.y = _y
self.angle = _a
def get_co(self):
return self.x, self.y
def draw_hull(hull):
for i in range(len(hull) - 1):
canvas.create_line(hull[i][0], hull[i][1], hull[i + 1][0], hull[i + 1][1], fill="red", width=2)
def draw_line(p1, p2, color="yellow"):
return canvas.create_line(p1.x, p1.y, p2.x, p2.y, fill=color, width=2)
def convex_hull(list_points):
# find bottom point
bottom_point = Point(math.inf, math.inf)
for point in list_points:
if point[1] < bottom_point.y:
bottom_point = Point(point[0], point[1])
# calculate angles between the bottom point and the other points
points = []
for point in list_points:
if point != bottom_point.get_co():
new_point = Point(point[0], point[1])
angle = calculate_angle(bottom_point, new_point)
new_point.angle = angle
points.append(new_point)
# sort the points by angle
swaps = None
while swaps != 0:
swaps = 0
for i in range(len(points) - 1):
point1 = points[i]
point2 = points[i + 1]
if point1.angle > point2.angle:
points[i], points[i + 1] = points[i + 1], points[i]
swaps += 1
# go through the points and add them to the convex hull
# if the angle between 3 points ever exeeds 180 degrees, discard the middle point
hull = [bottom_point, points[0]]
i = 1
while i < len(points):
####### DRAW LINE #######
canvas.after(i*500, draw_line, hull[-2], hull[-1])
##############
# check angle
angle = calculate_angle(hull[-2], hull[-1], points[i])
if angle == -1:
########## DELETE LINE ##########
# change color of line to red and delete it a bit later
# canvas.itemconfig(line, fill="red")
# canvas.after(i*500+250, canvas.delete, line)
####################
# pop the point of the stack
hull.pop()
else:
########## CHANGE COLOR OF LINE ##########
# change color of line to green
# canvas.itemconfig(line, fill="green")
####################
# move to the next point
hull.append(points[i])
i += 1
# add bottom point again for loop
hull.append(bottom_point)
# give easy return list (with coordinate-tupels not class objects)
output = []
for point in hull:
output.append(point.get_co())
return output
def calculate_angle(point1, point2, point3=None):
if point3 is None:
if point2.x - point1.x == 0:
return 90
elif point2.x - point1.x > 0:
return math.degrees(math.atan((point2.y - point1.y)/(point2.x - point1.x)))
else:
return 180 - math.degrees(math.atan((point2.y - point1.y)/(point1.x - point2.x)))
else:
v1 = Point(point1.x - point2.x, point1.y - point2.y)
v2 = Point(point3.x - point2.x, point3.y - point2.y)
det = (v1.x * v2.y) - (v2.x * v1.y)
if det < 0:
return 1
else:
return -1
window = Tk()
window.geometry("1000x600")
canvas = Canvas(window, width=1000, height=600)
canvas.pack()
POINTSIZE = 2
points = []
for i in range(100):
x = random.randint(50, 950)
y = random.randint(50, 550)
points.append((x, y))
canvas.create_oval(x - POINTSIZE, y - POINTSIZE, x + POINTSIZE, y + POINTSIZE, fill="black")
hull = convex_hull(points)
# draw_hull(hull)
window.mainloop()

If you have questions about the code, let me know. Because I dont know where to start to explain, since I made major changes to your code.
Anyway, I would be glad if you share your code again, once you are done with, on CodeReview and please do let me know. Because it was fun to work with and your code seems incomplete to me.
Happy Coding:
import tkinter as tk
import random
import math
class Point:
def __init__(self, _x, _y, _a=0):
self.x = _x
self.y = _y
self.angle = _a
return None
def get_co(self):
return self.x, self.y
class Window(tk.Tk):
def __init__(self,_w,_h):
super().__init__()
self.POINTSIZE = 2
self.points = []
self.swaps = None
self.count = 1
self.delay = 200
self.title('Graham scan simulation')
self.toolbar = tk.Frame(self,background='grey')
self.refresh_button = tk.Button(self.toolbar,text='Refresh',
command=self.refresh)
self.start_button = tk.Button(self.toolbar,text='Start',
command = self.convex_hull)
self.canvas = tk.Canvas(self,width=_w,height=_h)
self.toolbar.pack(side=tk.TOP,fill=tk.BOTH,expand=True)
self.refresh_button.pack(side=tk.LEFT)
self.start_button.pack(side=tk.LEFT)
self.canvas.pack(side=tk.BOTTOM,fill=tk.BOTH,expand=True)
def generate_points(self):
for point_instance in self.points:
yield point_instance
def find_bottom_point(self):
bottom_point = Point(math.inf,math.inf)
for point in self.generate_points():
if point.y < bottom_point.y:
bottom_point = point
return bottom_point
def calculate_angle(self,point1, point2):
if point2.x - point1.x == 0:
return 90
elif point2.x - point1.x > 0:
return math.degrees(math.atan((point2.y - point1.y)/(point2.x - point1.x)))
else:
return 180 - math.degrees(math.atan((point2.y - point1.y)/(point1.x - point2.x)))
def calculate_angels_by_bottom_point(self,bottom_point):
for point in self.generate_points():
if point != bottom_point:
angle = self.calculate_angle(bottom_point,point)
point.angle = angle
def sort_points(self,event_variable):
if self.swaps != 0:
self.swaps = 0
for i in range(len(self.points)-1):
point1 = self.points[i]
point2 = self.points[i + 1]
if point1.angle > point2.angle:
self.points[i], self.points[i + 1] = self.points[i + 1], self.points[i]
self.swaps += 1
if self.swaps == 0:
event_variable.set(1)
self.after(20,self.sort_points,event_variable)
def check_angle(self,point1,point2,point3):
v1 = Point(point1.x - point2.x, point1.y - point2.y)
v2 = Point(point3.x - point2.x, point3.y - point2.y)
det = (v1.x * v2.y) - (v2.x * v1.y)
if det < 0:
return 1
else:
return -1
def draw_line(self,p1,p2,color='yellow'):
return self.canvas.create_line(p1.x,p1.y, p2.x,p2.y, fill='yellow',tags='line')
def clear_red_lines(self,p1,p2):
shapes = self.canvas.find_withtag('line')
for shape in shapes:
if self.canvas.itemcget(shape,'fill') == 'red':
coords = self.canvas.coords(shape)
overlapped = self.canvas.find_overlapping(*coords)
for i in overlapped:
coords2 = self.canvas.coords(i)
if coords == coords2:
self.canvas.delete(i)
self.canvas.delete(shape)
def animated_draw(self,hull):
if self.count != len(self.points):
line = self.draw_line(hull[-2],hull[-1])
check_mark = self.check_angle(hull[-2],hull[-1],self.points[self.count])
if check_mark == -1:
self.canvas.itemconfig(line,fill='red')
self.after(self.delay-100,lambda:self.clear_red_lines(hull[-2],hull[-1]))
hull.pop()
else:
self.canvas.itemconfig(line,fill='green')
hull.append(self.points[self.count])
self.count += 1
self.after(self.delay,self.animated_draw,hull)
def convex_hull(self):
bottom_point = self.find_bottom_point()
self.calculate_angels_by_bottom_point(bottom_point)
event_variable = tk.IntVar(self,value=0)
self.sort_points(event_variable)
self.wait_variable(event_variable)
self.points.pop(0)
self.animated_draw(hull = [bottom_point, self.points[0]])
def generate_listpoints(self,_amount):
'''using a generator for memory purpose'''
for i in range(_amount):
x = random.randint(50, 950)
y = random.randint(50, 550)
yield x,y
def refresh(self):
self.swaps = None
self.count = 1
self.points= []
self.populate_canvas()
def populate_canvas(self):
self.canvas.delete('all')
for x,y in self.generate_listpoints(100):
self.points.append(Point(x, y))#instead of creating throwing instances away.
self.canvas.create_oval(x - self.POINTSIZE,
y - self.POINTSIZE,
x + self.POINTSIZE,
y + self.POINTSIZE,
fill="black")
root = Window(1000,600)
root.mainloop()

Qt callout example with more than one y axis

I have a QChart from the Callout example of PySide6. Now I have rewritten some of the code for my project, but when I hover over a `QLineSeries' the callout appears higher or lower than where I am actually pointing.
Here is some code:
The Callout class (Almost the same as in the example)
class Callout(QGraphicsItem):
def __init__(self, chart):
QGraphicsItem.__init__(self, chart)
self.chart = chart
self._text = ""
self._textRect = QRectF()
self._anchor = QPointF()
self._font = QFont()
self._rect = QRectF()
def boundingRect(self):
anchor = self.mapFromParent(self.chart.mapToPosition(self._anchor))
rect = QRectF()
rect.setLeft(min(self._rect.left(), anchor.x()))
rect.setRight(max(self._rect.right(), anchor.x()))
rect.setTop(min(self._rect.top(), anchor.y()))
rect.setBottom(max(self._rect.bottom(), anchor.y()))
return rect
def paint(self, painter, option, widget):
path = QPainterPath()
path.addRoundedRect(self._rect, 5, 5)
anchor = self.mapFromParent(self.chart.mapToPosition(self._anchor))
if not self._rect.contains(anchor) and not self._anchor.isNull():
point1 = QPointF()
point2 = QPointF()
# establish the position of the anchor point in relation to _rect
above = anchor.y() <= self._rect.top()
above_center = (anchor.y() > self._rect.top() and
anchor.y() <= self._rect.center().y())
below_center = (anchor.y() > self._rect.center().y() and
anchor.y() <= self._rect.bottom())
below = anchor.y() > self._rect.bottom()
on_left = anchor.x() <= self._rect.left()
left_of_center = (anchor.x() > self._rect.left() and
anchor.x() <= self._rect.center().x())
right_of_center = (anchor.x() > self._rect.center().x() and
anchor.x() <= self._rect.right())
on_right = anchor.x() > self._rect.right()
# get the nearest _rect corner.
x = (on_right + right_of_center) * self._rect.width()
y = (below + below_center) * self._rect.height()
corner_case = ((above and on_left) or (above and on_right) or
(below and on_left) or (below and on_right))
vertical = abs(anchor.x() - x) > abs(anchor.y() - y)
x1 = (x + left_of_center * 10 - right_of_center * 20 + corner_case *
int(not vertical) * (on_left * 10 - on_right * 20))
y1 = (y + above_center * 10 - below_center * 20 + corner_case *
vertical * (above * 10 - below * 20))
point1.setX(x1)
point1.setY(y1)
x2 = (x + left_of_center * 20 - right_of_center * 10 + corner_case *
int(not vertical) * (on_left * 20 - on_right * 10))
y2 = (y + above_center * 20 - below_center * 10 + corner_case *
vertical * (above * 20 - below * 10))
point2.setX(x2)
point2.setY(y2)
path.moveTo(point1)
path.lineTo(anchor)
path.lineTo(point2)
path = path.simplified()
painter.setBrush(QColor(255, 255, 255))
painter.drawPath(path)
painter.drawText(self._textRect, self._text)
def mousePressEvent(self, event):
if event.button() == Qt.RightButton:
self.removecallout()
event.setAccepted(True)
def mouseMoveEvent(self, event):
if event.buttons() & Qt.LeftButton:
self.setPos(self.mapToParent(
event.pos() - event.buttonDownPos(Qt.LeftButton)))
event.setAccepted(True)
else:
event.setAccepted(False)
def set_text(self, text):
self._text = text
metrics = QFontMetrics(self._font)
self._textRect = QRectF(metrics.boundingRect(
QRect(0.0, 0.0, 150.0, 150.0), Qt.AlignLeft, self._text))
self._textRect.translate(5, 5)
self.prepareGeometryChange()
self._rect = self._textRect.adjusted(-5, -5, 5, 5)
def set_anchor(self, point):
self._anchor = QPointF(point)
def update_geometry(self):
self.prepareGeometryChange()
self.setPos(self.chart.mapToPosition(
self._anchor) + QPointF(10, -50))
def removecallout(self):
self.hide()
The Class which produces the chart:
class CreateChart(QChartView):
def __init__(self, data):
super().__init__()
self.serieses = self.getserieses(data)
i = 0
self.chart = QChart()
self.buddy = None
self.chart.legend().setVisible(False)
xaxis = QValueAxis()
xaxis.setTitleText("Time")
self.chart.addAxis(xaxis, Qt.AlignBottom)
for key in self.serieses.keys():
if i >= 100:
break
else:
self.serieses[key].setName(key)
self.chart.addSeries(self.serieses[key])
self.serieses[key].hovered.connect(self.tooltip) #The connections for the temporary callout of the coordinates
self.serieses[key].clicked.connect(self.keep_callout) #The connection for the permanent callout of the coordinates
axis = QValueAxis()
axis.setTitleText(key)
axis.setTitleBrush(self.serieses[key].color())
self.chart.addAxis(axis, Qt.AlignLeft if ((i % 2) == 0) else Qt.AlignRight)
self.serieses[key].attachAxis(axis)
self.serieses[key].attachAxis(xaxis)
i += 1
print("Finished Loading")
self.chart.legend().setMarkerShape(QLegend.MarkerShapeFromSeries)
self.chart_view = super()
self.chart_view.setRenderHint(QPainter.Antialiasing)
self.chart_view.setChart(self.chart)
#self.chart_view.setMaximumWidth(300)
#QGraphicsView.RubberbandDrag = Selecting an area which can be retrieved by **Your QChartView**.rubberBandRect()
self.chart_view.setDragMode(QGraphicsView.RubberBandDrag)
self.chart_view.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff) #Don't need these, as they don't move the Graph. but the whole window
self.chart_view.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff) # ^
self.chart.setFocusPolicy(Qt.NoFocus)
self._tooltip = Callout(self.chart)
self._callouts = []
self.setMouseTracking(True) #Must be on
def tooltip(self, point, state):
#point = self.Mouse
if self._tooltip == 0:
self._tooltip = Callout(self._chart)
if state:
x = point.x()
y = point.y()
self._tooltip.set_text(f"X: {x:.1f} \nY: {y:.1f} ")
self._tooltip.set_anchor(point)
self._tooltip.setZValue(11)
self._tooltip.update_geometry()
self._tooltip.show()
else:
self._tooltip.hide()
def keep_callout(self):
self._callouts.append(self._tooltip)
self._tooltip = Callout(self.chart)
Now when I execute this the callouts appear perfect on one series, but on all the others the callouts appear above or below where my mouse is actually located, as the callout gets drawn on a different axis than the series is

Showing tooltip in a Qt chart with multiple y axes
Answer to this question could be found here in C++, answered by eyllanesc.
Here is a PySide6 version of the answer.
"""PySide6 port of the Callout example from Qt v5.x"""
import sys
from PySide6.QtWidgets import (QApplication, QGraphicsScene,
QGraphicsView, QGraphicsSimpleTextItem, QGraphicsItem)
from PySide6.QtCore import Qt, QPointF, QRectF, QRect
from PySide6.QtCharts import QChart, QChartView, QLineSeries, QSplineSeries, QValueAxis
from PySide6.QtGui import QPainter, QFont, QFontMetrics, QPainterPath, QColor
class Callout(QGraphicsItem):
def __init__(self, chart, series):
QGraphicsItem.__init__(self, chart)
self._chart = chart
self._series = series
self._text = ""
self._textRect = QRectF()
self._anchor = QPointF()
self._font = QFont()
self._rect = QRectF()
def boundingRect(self):
anchor = self.mapFromParent(
self._chart.mapToPosition(self._anchor, self._series))
rect = QRectF()
rect.setLeft(min(self._rect.left(), anchor.x()))
rect.setRight(max(self._rect.right(), anchor.x()))
rect.setTop(min(self._rect.top(), anchor.y()))
rect.setBottom(max(self._rect.bottom(), anchor.y()))
return rect
def paint(self, painter, option, widget):
path = QPainterPath()
path.addRoundedRect(self._rect, 5, 5)
anchor = self.mapFromParent(
self._chart.mapToPosition(self._anchor, self._series))
if not self._rect.contains(anchor) and not self._anchor.isNull():
point1 = QPointF()
point2 = QPointF()
# establish the position of the anchor point in relation to _rect
above = anchor.y() <= self._rect.top()
above_center = (anchor.y() > self._rect.top() and
anchor.y() <= self._rect.center().y())
below_center = (anchor.y() > self._rect.center().y() and
anchor.y() <= self._rect.bottom())
below = anchor.y() > self._rect.bottom()
on_left = anchor.x() <= self._rect.left()
left_of_center = (anchor.x() > self._rect.left() and
anchor.x() <= self._rect.center().x())
right_of_center = (anchor.x() > self._rect.center().x() and
anchor.x() <= self._rect.right())
on_right = anchor.x() > self._rect.right()
# get the nearest _rect corner.
x = (on_right + right_of_center) * self._rect.width()
y = (below + below_center) * self._rect.height()
corner_case = ((above and on_left) or (above and on_right) or
(below and on_left) or (below and on_right))
vertical = abs(anchor.x() - x) > abs(anchor.y() - y)
x1 = (x + left_of_center * 10 - right_of_center * 20 + corner_case *
int(not vertical) * (on_left * 10 - on_right * 20))
y1 = (y + above_center * 10 - below_center * 20 + corner_case *
vertical * (above * 10 - below * 20))
point1.setX(x1)
point1.setY(y1)
x2 = (x + left_of_center * 20 - right_of_center * 10 + corner_case *
int(not vertical) * (on_left * 20 - on_right * 10))
y2 = (y + above_center * 20 - below_center * 10 + corner_case *
vertical * (above * 20 - below * 10))
point2.setX(x2)
point2.setY(y2)
path.moveTo(point1)
path.lineTo(anchor)
path.lineTo(point2)
path = path.simplified()
painter.setBrush(QColor(255, 255, 255))
painter.drawPath(path)
painter.drawText(self._textRect, self._text)
def mousePressEvent(self, event):
event.setAccepted(True)
def mouseMoveEvent(self, event):
if event.buttons() & Qt.LeftButton:
self.setPos(self.mapToParent(
event.pos() - event.buttonDownPos(Qt.LeftButton)))
event.setAccepted(True)
else:
event.setAccepted(False)
def set_text(self, text):
self._text = text
metrics = QFontMetrics(self._font)
self._textRect = QRectF(metrics.boundingRect(
QRect(0.0, 0.0, 150.0, 150.0), Qt.AlignLeft, self._text))
self._textRect.translate(5, 5)
self.prepareGeometryChange()
self._rect = self._textRect.adjusted(-5, -5, 5, 5)
def set_anchor(self, point):
self._anchor = QPointF(point)
def update_geometry(self):
self.prepareGeometryChange()
self.setPos(self._chart.mapToPosition(
self._anchor, self._series) + QPointF(10, -50))
def setSeries(self, series):
self._series = series
class View(QChartView):
def __init__(self, parent=None):
super().__init__(parent)
self.setScene(QGraphicsScene(self))
self.setDragMode(QGraphicsView.RubberBandDrag)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
# Chart
self._chart = QChart()
self._chart.setMinimumSize(640, 480)
self._chart.setTitle("Hover the line to show callout. Click the line "
"to make it stay")
self._chart.legend().hide()
self.series = QLineSeries()
self.series.append(1, 3)
self.series.append(4, 5)
self.series.append(5, 4.5)
self.series.append(7, 1)
self.series.append(11, 2)
self._chart.addSeries(self.series)
self.series2 = QSplineSeries()
self.series2.append(1.6, 1.4)
self.series2.append(2.4, 3.5)
self.series2.append(3.7, 2.5)
self.series2.append(7, 4)
self.series2.append(10, 2)
self._chart.addSeries(self.series2)
xaxis = QValueAxis()
xaxis.setTitleText("X")
self._chart.addAxis(xaxis, Qt.AlignBottom)
yaxis = QValueAxis()
yaxis.setTitleText("YR")
self._chart.addAxis(yaxis, Qt.AlignRight)
y2axis = QValueAxis()
y2axis.setTitleText("YL")
self._chart.addAxis(y2axis, Qt.AlignLeft)
self.series.attachAxis(xaxis)
self.series.attachAxis(y2axis)
self.series2.attachAxis(xaxis)
self.series2.attachAxis(yaxis)
self._chart.setAcceptHoverEvents(True)
self.setRenderHint(QPainter.Antialiasing)
self.scene().addItem(self._chart)
self._coordX = QGraphicsSimpleTextItem(self._chart)
self._coordX.setPos(
self._chart.size().width() / 2 - 50, self._chart.size().height())
self._coordX.setText("X: ")
self._coordY = QGraphicsSimpleTextItem(self._chart)
self._coordY.setPos(
self._chart.size().width() / 2 + 50, self._chart.size().height())
self._coordY.setText("Y: ")
self._callouts = []
self._tooltip = Callout(self._chart, self.series)
self.series.clicked.connect(self.keep_callout)
self.series.hovered.connect(self.tooltip)
self.series2.clicked.connect(self.keep_callout)
self.series2.hovered.connect(self.tooltip)
self.setMouseTracking(True)
def resizeEvent(self, event):
if self.scene():
self.scene().setSceneRect(QRectF(QPointF(0, 0), event.size()))
self._chart.resize(event.size())
self._coordX.setPos(
self._chart.size().width() / 2 - 50,
self._chart.size().height() - 20)
self._coordY.setPos(
self._chart.size().width() / 2 + 50,
self._chart.size().height() - 20)
for callout in self._callouts:
callout.update_geometry()
QGraphicsView.resizeEvent(self, event)
def mouseMoveEvent(self, event):
pos = self._chart.mapToValue(event.pos())
x = pos.x()
y = pos.y()
self._coordX.setText(f"X: {x:.2f}")
self._coordY.setText(f"Y: {y:.2f}")
QGraphicsView.mouseMoveEvent(self, event)
def keep_callout(self):
series = self.sender()
self._callouts.append(self._tooltip)
self._tooltip = Callout(self._chart, series)
def tooltip(self, point, state):
series = self.sender()
if self._tooltip == 0:
self._tooltip = Callout(self._chart, series)
if state:
x = point.x()
y = point.y()
self._tooltip.setSeries(series)
self._tooltip.set_text(f"X: {x:.2f} \nY: {y:.2f} ")
self._tooltip.set_anchor(point)
self._tooltip.setZValue(11)
self._tooltip.update_geometry()
self._tooltip.show()
else:
self._tooltip.hide()
if __name__ == "__main__":
app = QApplication(sys.argv)
v = View()
v.show()
sys.exit(app.exec())

Only Color Gradient from Qt5 ColorDialog

I wanted to ask if it is possible to use only the Color Gradient(red surrounded) part of the QColorDialog.
I am using PyQt5 and Python3 on different Linux machines (ubuntu + raspian).

It is only necessary to hide all the elements except the QColorPicker and QColorLuminancePicker.
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class ColorDialog(QtWidgets.QColorDialog):
def __init__(self, parent=None):
super().__init__(parent)
self.setOptions(self.options() | QtWidgets.QColorDialog.DontUseNativeDialog)
for children in self.findChildren(QtWidgets.QWidget):
classname = children.metaObject().className()
if classname not in ("QColorPicker", "QColorLuminancePicker"):
children.hide()
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
colordialog = ColorDialog()
label = QtWidgets.QLabel(alignment=QtCore.Qt.AlignCenter)
def onCurrentColorChanged(color):
label.setStyleSheet("background-color: {}".format(color.name()))
colordialog.currentColorChanged.connect(onCurrentColorChanged)
onCurrentColorChanged(colordialog.currentColor())
w = QtWidgets.QWidget()
lay = QtWidgets.QVBoxLayout(w)
lay.addWidget(colordialog, alignment=QtCore.Qt.AlignCenter)
lay.addWidget(label)
w.show()
sys.exit(app.exec_())

The solution proposed by eyllanesc is perfect (and smart) as always.
Nonetheless, some months ago I had to implement my own color picker widget, which creates the "color rainbow" widget only from code, and I'd like to share part of that code as I believe it could be of some interest, especially regarding the creation of the "rainbow" and the color detection.
I've edited it down to make it a basic usable "color picker" widget.
from PyQt5 import QtCore, QtGui, QtWidgets
# a helper function that ensures that a value is between the given range
sanitize = lambda m, value, M: min(max(m, value), M)
class RgbPicker(QtWidgets.QLabel):
colorGrads = QtGui.QLinearGradient(0, 0, 1, 0)
colorGrads.setCoordinateMode(colorGrads.ObjectBoundingMode)
xRatio = 1. / 6
# the basic "rainbow" gradient
colorGrads.setColorAt(0, QtCore.Qt.red)
colorGrads.setColorAt(1, QtCore.Qt.red)
colorGrads.setColorAt(xRatio, QtCore.Qt.magenta)
colorGrads.setColorAt(xRatio * 2, QtCore.Qt.blue)
colorGrads.setColorAt(xRatio * 3, QtCore.Qt.cyan)
colorGrads.setColorAt(xRatio * 4, QtCore.Qt.green)
colorGrads.setColorAt(xRatio * 5, QtCore.Qt.yellow)
# the superimposed white component
maskGrad = QtGui.QLinearGradient(0, 0, 0, 1)
maskGrad.setCoordinateMode(maskGrad.ObjectBoundingMode)
maskGrad.setColorAt(0, QtCore.Qt.transparent)
maskGrad.setColorAt(1, QtCore.Qt.white)
# the pseudo arrow cursor
cursorPath = QtGui.QPainterPath()
cursorPath.moveTo(-10, 0)
cursorPath.lineTo(-4, 0)
cursorPath.moveTo(0, -10)
cursorPath.lineTo(0, -4)
cursorPath.moveTo(4, 0)
cursorPath.lineTo(10, 0)
cursorPath.moveTo(0, 4)
cursorPath.lineTo(0, 10)
cursorPen = QtGui.QPen(QtCore.Qt.black, 3)
colorChanged = QtCore.pyqtSignal(QtGui.QColor)
def __init__(self, color=None):
QtWidgets.QLabel.__init__(self)
self.setFocusPolicy(QtCore.Qt.StrongFocus)
self.setFixedSize(220, 200)
# create a pixmap that shows the "rainbow" and draw its contents
pixmap = QtGui.QPixmap(self.size())
qp = QtGui.QPainter(pixmap)
qp.fillRect(pixmap.rect(), self.colorGrads)
qp.fillRect(pixmap.rect(), self.maskGrad)
qp.end()
self.setPixmap(pixmap)
self.image = pixmap.toImage()
# a multiplier, used when an arrow key is kept pressed
self.keyTimer = QtCore.QTimer()
self.keyTimer.setInterval(1000)
self.keyTimer.timeout.connect(lambda: setattr(self, 'keyMulti', self.keyMulti + 1))
self._cursorPos = QtCore.QPoint()
self._color = color
self.setColor(color)
#property
def color(self):
return self._color
#property
def cursorPos(self):
return self._cursorPos
#cursorPos.setter
def cursorPos(self, pos):
self._cursorPos = pos
self.update()
def sanitizePos(self, pos):
# sanitize the position within the color rainbow margins
return QtCore.QPoint(sanitize(0, pos.x(), self.width() - 1), sanitize(0, pos.y(), self.height() - 1))
def setColor(self, color):
h, s, v, a = color.getHsv()
# compute the coordinates based on hsv components
x = (360 - h) * (self.width() - 1) / 360.
y = (255 - s) * (self.height() - 1) / 255.
self.cursorPos = QtCore.QPoint(x, y)
def translateColorCursor(self, pos):
# return the color of the given pixel
return QtGui.QColor(self.image.pixel(pos))
def mousePressEvent(self, event):
pos = self.sanitizePos(event.pos())
self._color = self.translateColorCursor(pos)
self.colorChanged.emit(QtGui.QColor(self._color))
self.cursorPos = pos
def mouseMoveEvent(self, event):
pos = self.sanitizePos(event.pos())
self._color = self.translateColorCursor(pos)
self.colorChanged.emit(QtGui.QColor(self._color))
self.cursorPos = pos
def keyPressEvent(self, event):
deltaX = deltaY = 0
# emulation of the Qt internal color picker keyboard navigation
if event.modifiers() & QtCore.Qt.KeypadModifier:
if event.key() in (QtCore.Qt.Key_7, QtCore.Qt.Key_Home):
deltaX = deltaY = -1
elif event.key() in (QtCore.Qt.Key_8, QtCore.Qt.Key_Up):
deltaY = -1
elif event.key() in (QtCore.Qt.Key_9, QtCore.Qt.Key_PageUp):
deltaX = 1
deltaY = -1
elif event.key() in (QtCore.Qt.Key_4, QtCore.Qt.Key_Left):
deltaX = -1
elif event.key() in (QtCore.Qt.Key_6, QtCore.Qt.Key_Right):
deltaX = 1
elif event.key() in (QtCore.Qt.Key_1, QtCore.Qt.Key_End):
deltaX = -1
deltaY = 1
elif event.key() in (QtCore.Qt.Key_2, QtCore.Qt.Key_Down):
deltaY = 1
elif event.key() in (QtCore.Qt.Key_3, QtCore.Qt.Key_PageDown):
deltaX = deltaY = 1
elif event.key() == QtCore.Qt.Key_Left:
deltaX = -1
elif event.key() == QtCore.Qt.Key_Right:
deltaX = 1
elif event.key() == QtCore.Qt.Key_Up:
deltaY = -1
elif event.key() == QtCore.Qt.Key_Down:
deltaY = 1
elif event.key() == QtCore.Qt.Key_Home:
if event.modifiers() == QtCore.Qt.ShiftModifier:
deltaY = -1000
elif event.modifiers() == QtCore.Qt.ControlModifier:
deltaX = deltaY = -1000
else:
deltaX = -1000
elif event.key() == QtCore.Qt.Key_End:
if event.modifiers() == QtCore.Qt.ShiftModifier:
deltaY = 1000
elif event.modifiers() == QtCore.Qt.ControlModifier:
deltaX = deltaY = 1000
else:
deltaX = 1000
elif event.key() == QtCore.Qt.Key_PageUp and not event.modifiers() & QtCore.Qt.KeypadModifier:
deltaY = -10
elif event.key() == QtCore.Qt.Key_PageDown and not event.modifiers() & QtCore.Qt.KeypadModifier:
deltaY = +10
else:
return QtWidgets.QWidget.keyPressEvent(self, event)
if not event.isAutoRepeat():
self.keyTimer.start()
self.keyMulti = 1
if deltaX or deltaY:
multi = self.keyMulti
if event.modifiers() & QtCore.Qt.ShiftModifier:
multi *= 10
deltaX *= multi
deltaY *= multi
pos = self.sanitizePos(QtCore.QPoint(self.cursorPos.x() + deltaX, self.cursorPos.y() + deltaY))
self._color = self.translateColorCursor(pos)
self.colorChanged.emit(QtGui.QColor(self._color))
self.cursorPos = pos
def keyReleaseEvent(self, event):
if not event.isAutoRepeat():
self.keyTimer.stop()
QtWidgets.QWidget.keyReleaseEvent(self, event)
def paintEvent(self, event):
QtWidgets.QLabel.paintEvent(self, event)
qp = QtGui.QPainter(self)
qp.setPen(self.cursorPen)
# translate to the crosshair position and paint it
qp.translate(self.cursorPos)
qp.drawPath(self.cursorPath)
class BlackPicker(QtWidgets.QWidget):
# the "black" selector, which has a gradient based on the current selected
# color of the RgbPicker (selected color -> black)
_rect = QtCore.QRect(0, 8, 16, 200)
grad = QtGui.QLinearGradient(0, 0, 0, 1)
grad.setCoordinateMode(grad.ObjectBoundingMode)
grad.setColorAt(1, QtCore.Qt.black)
arrow = QtGui.QPainterPath()
arrow.lineTo(4, -4)
arrow.lineTo(4, 4)
arrow.closeSubpath()
_color = QtGui.QColor()
_black = -1
blackChanged = QtCore.pyqtSignal(float)
def __init__(self, color):
QtWidgets.QWidget.__init__(self)
self.color = QtGui.QColor(color)
self.setFixedSize(22, 216)
#property
def black(self):
return self._black
#black.setter
def black(self, black):
if black == self._black:
return
self._black = black
self.update()
self.blackChanged.emit(black)
#property
def color(self):
return self._color
#color.setter
def color(self, color):
if color == self._color:
return
self._color = QtGui.QColor(color)
self.grad.setColorAt(0, color)
self.black = color.getCmykF()[3]
def setWhiteColor(self, color):
self.grad.setColorAt(0, color)
self.update()
def setColor(self, color):
self.color = color
def mousePressEvent(self, event):
self.black = sanitize(0, event.pos().y() - self._rect.top(),
self._rect.height()) / 200.
def mouseMoveEvent(self, event):
self.black = sanitize(0, event.pos().y() - self._rect.top(),
self._rect.height()) / 200.
def wheelEvent(self, event):
if event.pixelDelta().y() < 0:
delta = .01
else:
delta = -.01
self.black = sanitize(0, self.black + delta, 1)
def paintEvent(self, event):
qp = QtGui.QPainter(self)
qp.setRenderHints(qp.Antialiasing)
qp.fillRect(self._rect, self.grad)
qp.translate(self._rect.right() + 2, self._rect.top() + self.black * self._rect.height())
qp.setBrush(QtCore.Qt.black)
qp.translate(.5, .5)
qp.drawPath(self.arrow)
class ColorPicker(QtWidgets.QWidget):
colorChanged = QtCore.pyqtSignal(QtGui.QColor)
def __init__(self, color=None, parent=None):
super().__init__(parent)
layout = QtWidgets.QGridLayout(self)
if not (isinstance(color, QtGui.QColor) and color.isValid()):
if isinstance(color, QtCore.Qt.GlobalColor):
color = QtGui.QColor(color)
else:
color = self.palette().color(QtGui.QPalette.WindowText)
self.rgbPicker = RgbPicker(color)
layout.addWidget(self.rgbPicker, 0, 0)
self.blackPicker = BlackPicker(color)
layout.addWidget(self.blackPicker, 0, 1)
self.colorWidget = QtWidgets.QWidget()
layout.addWidget(self.colorWidget, 1, 0, 1, 2)
self.colorWidget.setMinimumHeight(16)
self.colorWidget.setAutoFillBackground(True)
self.colorLabel = QtWidgets.QLabel()
layout.addWidget(self.colorLabel)
self.rgbPicker.colorChanged.connect(self.updateColor)
self.rgbPicker.colorChanged.connect(self.blackPicker.setWhiteColor)
self.blackPicker.blackChanged.connect(self.updateColor)
self.updateColor()
def updateColor(self):
color = self.rgbPicker.color
c, m, y, _, _ = color.getCmykF()
color.setCmykF(c, m, y, self.blackPicker.black)
palette = self.colorWidget.palette()
palette.setColor(palette.Window, color)
self.colorWidget.setPalette(palette)
r, g, b = color.getRgb()[:-1]
hexColor = '{:02X}{:02X}{:02X}'.format(r, g, b)
self.colorLabel.setText('R:{:03} G:{:03} B:{:03} - #{}'.format(
r, g, b, hexColor))
self.colorChanged.emit(color)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
picker = ColorPicker(QtGui.QColor(QtCore.Qt.white))
picker.show()
sys.exit(app.exec())

You can check out this Circular Color Picker design for PyQt
PyQt Circular ColorPicker
It looks like this and can be easily modified

how to repaint only part of a QWidget in PyQt4?

I'm trying to create a program that displays a large grid of numbers (say, filling up a 6 by 4000 grid), where the user can move a cursor around via keyboard or mouse and enter in numbers into the grid. (This is for a guitar tablature program.) I'm new to python GUI programming, and thus far my idea is to have a very large QWidget window (say, 1000x80000 pixels) inside of a QScrollArea inside of the main window. The problem is that every mouse click or cursor movement causes the whole thing to repaint, causing a delay, when I just want to repaint whatever changes I just made to make things faster. In PyQt, is there a way to buffer already-painted graphics and change just the graphics that need changing?
edit: I've posted the code below, which I've run with python3.3 on Mac OS 10.7. The main point is that in the TabWindow init function, the grid size can be set by numXGrid and numYGrid (currently set to 200 and 6), and this grid is filled with random numbers by the generateRandomTablatureData() method. If the grid is filled with numbers, then there's a noticeable lag with every key press, which gets worse with larger grids. (There is also an initial delay due to generating the data, but my question is on the delay after each key press which I assume is due to having to repaint every number.)
There are two files. This is the main one, which I called FAIT.py:
import time
start_time = time.time()
import random
import sys
from PyQt4 import QtGui, QtCore
import Tracks
# generate tracks
tracks = [Tracks.Track(), Tracks.Track(), Tracks.Track()]
fontSize = 16
# margins
xMar = 50
yMar = 50
trackMar = 50 # margin between tracks
class MainWindow(QtGui.QWidget):
def __init__(self):
super(MainWindow, self).__init__()
self.initUI()
end_time = time.time()
print("Initializing time was %g seconds" % (end_time - start_time))
def initUI(self):
# attach QScrollArea to MainWindow
l = QtGui.QVBoxLayout(self)
l.setContentsMargins(0,0,0,0)
l.setSpacing(0)
s=QtGui.QScrollArea()
l.addWidget(s)
# attach TabWindow to QScrollArea so we can paint on it
self.tabWindow=TabWindow(self)
self.tabWindow.setFocusPolicy(QtCore.Qt.StrongFocus)
self.setFocusPolicy(QtCore.Qt.NoFocus)
vbox=QtGui.QVBoxLayout(self.tabWindow)
s.setWidget(self.tabWindow)
self.positionWindow() # set size and position of main window
self.setWindowTitle('MainWindow')
self.show()
def positionWindow(self):
qr = self.frameGeometry()
cp = QtGui.QDesktopWidget().availableGeometry().center()
width = QtGui.QDesktopWidget().availableGeometry().width() - 100
height = QtGui.QDesktopWidget().availableGeometry().height() - 100
self.resize(width, height)
qr = self.frameGeometry()
cp = QtGui.QDesktopWidget().availableGeometry().center()
qr.moveCenter(cp)
self.move(qr.topLeft())
def keyPressEvent(self, e):
print('key pressed in MainWindow')
def mousePressEvent(self, e):
print('mouse click in MainWindow')
class TabWindow(QtGui.QWidget):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
# size of tablature grid
numXGrid = 200
numYGrid = 6
# initialize tablature information first
for i in range(0, len(tracks)):
tracks[i].numXGrid = numXGrid
self.arrangeTracks() # figure out offsets for each track
self.trackFocusNum = 0 # to begin with, focus is on track 0
self.windowSizeX = tracks[0].x0 + tracks[0].dx*(tracks[0].numXGrid+2)
self.windowSizeY = tracks[0].y0
for i in range(0, len(tracks)):
self.windowSizeY = self.windowSizeY + tracks[i].dy * tracks[i].numYGrid + trackMar
self.resize(self.windowSizeX,self.windowSizeY) # size of actual tablature area
# generate random tablature data for testing
self.generateRandomTablatureData()
def keyPressEvent(self, e):
print('key pressed in TabWindow')
i = self.trackFocusNum
if e.key() == QtCore.Qt.Key_Up:
tracks[i].moveCursorUp()
if e.key() == QtCore.Qt.Key_Down:
tracks[i].moveCursorDown()
if e.key() == QtCore.Qt.Key_Left:
tracks[i].moveCursorLeft()
if e.key() == QtCore.Qt.Key_Right:
tracks[i].moveCursorRight()
# check for number input
numberKeys = (QtCore.Qt.Key_0,
QtCore.Qt.Key_1,
QtCore.Qt.Key_2,
QtCore.Qt.Key_3,
QtCore.Qt.Key_4,
QtCore.Qt.Key_5,
QtCore.Qt.Key_6,
QtCore.Qt.Key_7,
QtCore.Qt.Key_8,
QtCore.Qt.Key_9)
if e.key() in numberKeys:
num = int(e.key())-48
# add data
tracks[i].data.addToTab(tracks[i].iCursor, tracks[i].jCursor, num)
# convert entered number to pitch and play note (do later)
# spacebar, backspace, or delete remove data
if e.key() in (QtCore.Qt.Key_Space, QtCore.Qt.Key_Backspace, QtCore.Qt.Key_Delete):
tracks[i].data.removeFromTab(tracks[i].iCursor, tracks[i].jCursor)
self.update()
def mousePressEvent(self, e):
print('mouse click in TabWindow')
xPos = e.x()
yPos = e.y()
# check tracks one by one
for i in range(0, len(tracks)):
if (tracks[i].isPositionInside(xPos, yPos)):
tracks[i].moveCursorToPosition(xPos, yPos)
self.trackFocusNum = i
break
else:
continue
self.update()
def paintEvent(self, e):
qp = QtGui.QPainter()
qp.begin(self)
qp.setPen(QtCore.Qt.black)
qp.setBrush(QtCore.Qt.white)
qp.drawRect(0, 0, self.windowSizeX, self.windowSizeY)
self.paintTracks(qp)
self.paintTunings(qp)
self.paintCursor(qp)
self.paintNumbers(qp)
qp.end()
def paintTracks(self, qp):
qp.setPen(QtCore.Qt.black)
qp.setBrush(QtCore.Qt.white)
for i in range(0, len(tracks)):
qp.drawPolyline(tracks[i].polyline)
def paintCursor(self, qp):
i = self.trackFocusNum
qp.setPen(QtCore.Qt.black)
qp.setBrush(QtCore.Qt.black)
qp.drawPolygon(tracks[i].getCursorQPolygon())
def paintNumbers(self, qp):
# iterate through tracks, and iterate through numbers on each track
for i in range(0, len(tracks)):
# make sure track has data to draw
if len(tracks[i].data.data) > 0:
for j in range(0, len(tracks[i].data.data)):
# do actual painting here
# first set color to be inverse cursor color if at cursor
if i == self.trackFocusNum and \
tracks[i].iCursor == tracks[i].data.data[j][0] and \
tracks[i].jCursor == tracks[i].data.data[j][1]:
qp.setPen(QtCore.Qt.white)
else:
qp.setPen(QtCore.Qt.black)
font = QtGui.QFont('Helvetica', fontSize)
qp.setFont(font)
text = str(tracks[i].data.data[j][2])
x1 = tracks[i].convertIndexToPositionX(tracks[i].data.data[j][0])
y1 = tracks[i].convertIndexToPositionY(tracks[i].data.data[j][1])
dx = tracks[i].dx
dy = tracks[i].dy
# height and width of number character(s)
metrics = QtGui.QFontMetrics(font)
tx = metrics.width(text)
ty = metrics.height()
# formula for alignment:
# xMar = (dx-tx)/2 plus offset
x11 = x1 + (dx-tx)/2
y11 = y1 + dy/2+ty/2
qp.drawText(x11, y11, text)
def paintTunings(self, qp):
qp.setPen(QtCore.Qt.black)
font = QtGui.QFont('Helvetica', fontSize)
qp.setFont(font)
for i in range(0, len(tracks)):
for j in range(0, tracks[i].numStrings):
text = tracks[i].convertPitchToLetter(tracks[i].stringTuning[j])
# height and width of characters
metrics = QtGui.QFontMetrics(font)
tx = metrics.width(text)
ty = metrics.height()
x11 = tracks[i].x0 - tx - 10
y11 = tracks[i].convertIndexToPositionY(j) + (tracks[i].dy+ty)/2
qp.drawText(x11, y11, text)
def arrangeTracks(self):
tracks[0].x0 = xMar
tracks[0].y0 = yMar
tracks[0].generateGridQPolyline()
for i in range(1, len(tracks)):
tracks[i].x0 = xMar
tracks[i].y0 = tracks[i-1].y0 + tracks[i-1].height + trackMar
tracks[i].generateGridQPolyline()
def generateRandomTablatureData(self):
t1 = time.time()
for i in range(0, len(tracks)):
# worst case scenario: fill every number
for jx in range(0, tracks[i].numXGrid):
for jy in range(0, tracks[i].numYGrid):
val = random.randint(0,9)
tracks[i].data.addToTab(jx, jy, val)
t2 = time.time()
print("Random number generating time was %g seconds" % (t2 - t1))
def main():
app = QtGui.QApplication(sys.argv)
ex = MainWindow()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
This is the other file, Tracks.py, which contains the Track class and supplementary methods:
# contains classes and methods relating to individual tracks
import math
from PyQt4 import QtGui, QtCore
# class for containing information about a track
class Track:
def __init__(self):
self.data = TabulatureData()
# position offset
self.x0 = 0
self.y0 = 0
self.dx = 20 # default rectangle width
self.dy = 40 # default rectangle height
# current cursor index coordinates
self.iCursor = 0
self.jCursor = 0
# default size of grid
self.numXGrid = 4000
self.numYGrid = 6
self.numStrings = self.numYGrid
# calculated maximum width and height in pixels
self.maxWidth = self.dx * self.numXGrid
self.maxHeight = self.dy * self.numYGrid
# generate points of grid and cursor
self.generateGridQPolyline()
# tuning
self.setTuning([40, 45, 50, 55, 59, 64])
# calculate bounds
self.height = self.numYGrid*self.dy
self.width = self.numXGrid*self.dx
def getCursorIndexX(self, xPos):
iPos = int(math.floor( (xPos-self.x0)/self.dx ))
return iPos
def getCursorIndexY(self, yPos):
jPos = int(math.floor( (yPos-self.y0)/self.dy ))
return jPos
def convertIndexToCoordinates(self, iPos, jPos):
return [self.ConvertIndexToPositionX(iPos),
self.ConvertIndexToPositionY(jPos)]
def convertIndexToPositionX(self, iPos):
return self.x0 + iPos*self.dx
def convertIndexToPositionY(self, jPos):
return self.y0 + jPos*self.dy
def getCursorQPolygon(self):
x1 = self.convertIndexToPositionX(self.iCursor)
y1 = self.convertIndexToPositionY(self.jCursor)
x2 = self.convertIndexToPositionX(self.iCursor+1)
y2 = self.convertIndexToPositionY(self.jCursor+1)
return QtGui.QPolygonF([QtCore.QPoint(x1, y1),
QtCore.QPoint(x1, y2),
QtCore.QPoint(x2, y2),
QtCore.QPoint(x2, y1)])
def generateGridQPolyline(self):
self.points = []
self.polyline = QtGui.QPolygonF()
for i in range(0, self.numXGrid):
for j in range(0, self.numYGrid):
x1 = self.convertIndexToPositionX(i)
y1 = self.convertIndexToPositionY(j)
x2 = self.convertIndexToPositionX(i+1)
y2 = self.convertIndexToPositionY(j+1)
self.points.append([(x1, y1), (x1, y2), (x2, y2), (x2, y1)])
self.polyline << QtCore.QPoint(x1,y1) << \
QtCore.QPoint(x1,y2) << \
QtCore.QPoint(x2,y2) << \
QtCore.QPoint(x2,y1) << \
QtCore.QPoint(x1,y1)
# smoothly connect different rows
jLast = self.numYGrid-1
x1 = self.convertIndexToPositionX(i)
y1 = self.convertIndexToPositionY(jLast)
x2 = self.convertIndexToPositionX(i+1)
y2 = self.convertIndexToPositionY(jLast+1)
self.polyline << QtCore.QPoint(x2,y1)
def isPositionInside(self, xPos, yPos):
if (xPos >= self.x0 and xPos <= self.x0 + self.width and
yPos >= self.y0 and yPos <= self.y0 + self.height):
return True
else:
return False
def moveCursorToPosition(self, xPos, yPos):
self.iCursor = self.getCursorIndexX(xPos)
self.jCursor = self.getCursorIndexY(yPos)
self.moveCursorToIndex(self.iCursor, self.jCursor)
def moveCursorToIndex(self, iPos, jPos):
# check if bounds are breached, and if cursor's already there,
# and if not, move cursor
if iPos == self.iCursor and jPos == self.jCursor:
return
if iPos >= 0 and iPos < self.numXGrid:
if jPos >= 0 and jPos < self.numYGrid:
self.iCursor = iPos
self.jCursor = jPos
return
def moveCursorUp(self):
self.moveCursorToIndex(self.iCursor, self.jCursor-1)
def moveCursorDown(self):
self.moveCursorToIndex(self.iCursor, self.jCursor+1)
def moveCursorLeft(self):
self.moveCursorToIndex(self.iCursor-1, self.jCursor)
def moveCursorRight(self):
self.moveCursorToIndex(self.iCursor+1, self.jCursor)
# return pitch in midi integer notation
def convertNumberToPitch(self, jPos, pitchNum):
return pitchNum + self.stringTuning[(self.numStrings-1) - jPos]
def convertPitchToLetter(self, pitchNum):
p = pitchNum % 12
letters = ('C', 'Db', 'D', 'Eb', 'E', 'F', 'Gb', 'G', 'Ab', 'A', 'Bb', 'B')
return letters[p]
def setTuning(self, tuning):
self.stringTuning = tuning
class TabulatureData:
def __init__(self):
self.data = []
def addToTab(self, i, j, value):
# check if data is already there, and remove it first
if self.getValue(i, j) > -1:
self.removeFromTab(i, j)
self.data.append([i, j, value])
def getValue(self, i, j):
possibleTuples = [x for x in self.data if x[0] == i and x[1] == j]
if possibleTuples == []:
return -1
elif len(possibleTuples) > 1:
print('Warning: more than one number at a location!')
return possibleTuples[0][2] # return third number of tuple
def removeFromTab(self, i, j):
# first get value, if it exists
value = self.getValue(i,j)
if value == -1:
return
else:
# if it exists, then remove
self.data.remove([i, j, value])

1000*80000 is really huge.
So,maybe you should try QGLWidget or something like that?
Or according to Qt document, you should set which region you want to repaint.
some slow widgets need to optimize by painting only the requested region: QPaintEvent::region(). This speed optimization does not change the result, as painting is clipped to that region during event processing. QListView and QTableView do this, for example.