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Convert 3D CBCT dicom to 2D Panaromic View

I want to generate 2D panarmoic view from the series of 3D cbct dental images by python.
I am converting the series of 3D Cbct images to 2D panaromic view by python. The code is working fine but the output is not complete.
import sys
import vtkmodules.all as vtk
from PyQt5 import QtCore, QtWidgets
from vtkmodules.qt.QVTKRenderWindowInteractor import QVTKRenderWindowInteractor
def create_reader(dir):
reader = vtk.vtkDICOMImageReader()
reader.SetDirectoryName(dir)
reader.Update()
return reader
def create_center(reader):
(xMin, xMax, yMin, yMax, zMin, zMax) = reader.GetExecutive().GetWholeExtent(reader.GetOutputInformation(0))
(xSpacing, ySpacing, zSpacing) = reader.GetOutput().GetSpacing()
(x0, y0, z0) = reader.GetOutput().GetOrigin()
center = [x0 + xSpacing * 0.5 * (xMin + xMax),
y0 + ySpacing * 0.5 * (yMin + yMax),
z0 + zSpacing * 0.5 * (zMin + zMax)]
return center
def create_sagittal_slice_matrix(center):
#Create Sagittal Slice Matrix
sagittal = vtk.vtkMatrix4x4()
sagittal.DeepCopy((0, 0, -1, center[0],
1, 0, 0, center[1],
0, -1, 0, center[2],
0, 0, 0, 1))
return sagittal
def create_resliced_image(reader, sagittal, frame):
# Reslice image
widget = QVTKRenderWindowInteractor(frame)
slice = vtk.vtkImageReslice()
slice.SetInputConnection(reader.GetOutputPort())
slice.SetOutputDimensionality(2)
slice.SetResliceAxes(sagittal)
slice.SetInterpolationModeToLinear()
return widget, slice
def create_display_image_actor(slice):
# Display the image
actor = vtk.vtkImageActor()
actor.GetMapper().SetInputConnection(slice.GetOutputPort())
# renderer = vtk.vtkRenderer()
return actor
def adjust_renderer_settings(renderer, widget, actor):
# Remove Renderer And Reset
renderer.RemoveAllViewProps()
renderer.ResetCamera()
widget.GetRenderWindow().Render()
renderer.AddActor(actor)
widget.GetRenderWindow().AddRenderer(renderer)
return widget
def setup_interaction(widget):
# Set up the interaction
slice_interactorStyle = vtk.vtkInteractorStyleImage()
slice_interactor = widget.GetRenderWindow().GetInteractor()
slice_interactor.SetInteractorStyle(slice_interactorStyle)
widget.GetRenderWindow().SetInteractor(slice_interactor)
widget.GetRenderWindow().Render()
return slice_interactor
# Start interaction
# slice_interactor.Start()
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent = None):
QtWidgets.QMainWindow.__init__(self, parent)
self.frame = QtWidgets.QFrame()
self.vl = QtWidgets.QVBoxLayout()
reader = create_reader(r"C:\work.ateeb\2.16.840.114421.10241.9572018034.9603554034\DECOMPRESSED\One")
center = create_center(reader)
sagittal = create_sagittal_slice_matrix(center)
self.vtkWidget, slice = create_resliced_image(reader, sagittal, self.frame)
self.vl.addWidget(self.vtkWidget)
# create renderer
renderer = vtk.vtkRenderer()
# create actor
actor = create_display_image_actor(slice)
self.vtkWidget = adjust_renderer_settings(renderer, self.vtkWidget, actor)
slice_interactor = setup_interaction(self.vtkWidget)
self.show()
self.frame.setLayout(self.vl)
self.setCentralWidget(self.frame)
slice_interactor.Initialize()
slice_interactor.Start()
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
window = MainWindow()
sys.exit(app.exec_())
I was expecting the output like this
enter image description here
But the output the code is generating is:
enter image description here

Add glumpy widget to PyQt5 GUI

I have a simple GUI onto which I am plotting images. I create Widgets for text outputs and arrays plots, and I would like to add one for 3D visualtion using glumpy, say to show this example from the glumpy documentation.
What I would like is an "extra" slot on which to have the glumpy output:
I saw for example in this GitHub thread that people were referring to PyQt5 and glumpy integration, but I only see snippets of code and noting that works as a standalone example.
Also, it seems glumpy is already using PyQt5 in the backend (here), but I don't understand this well enough to know if and how I can access it a posteriori?
This is my MWE:
from PyQt5 import QtGui, QtCore
import pyqtgraph as pg
import sys
width = 1000
height = 500
class layout():
def setup(self, window):
self.window = window
self.window.resize(width, height)
self.centralwidget = QtGui.QWidget(self.window)
self.horizontallayout = QtGui.QHBoxLayout(self.centralwidget)
self.window.setCentralWidget(self.centralwidget)
self.dialogue = QtGui.QTextEdit()
self.horizontallayout.addWidget(self.dialogue)
self.plot = pg.GraphicsLayoutWidget(self.window)
self.horizontallayout.addWidget(self.plot)
self.plot1 = self.plot.addPlot(colspan=1)
class Window(pg.Qt.QtGui.QMainWindow, layout):
def __init__(self, shot = None):
super(Window, self).__init__()
self.setup(self)
self.show()
if __name__ == '__main__':
app = pg.Qt.QtGui.QApplication([])
Window()
sys.exit(app.exec_())

You have to get the internal QGLWidget through the "_native_window" attribute. The following example is based on the official example geometry-surface.py .
import sys
from PyQt5 import QtGui, QtCore
import pyqtgraph as pg
import numpy as np
from glumpy import app as glumpy_app, gl, gloo, data, library
from glumpy.geometry import primitives
from glumpy.transforms import Trackball
width = 1000
height = 500
glumpy_app.use("qt5")
vertex = """
#include "misc/spatial-filters.frag"
uniform float height;
uniform sampler2D data;
uniform vec2 data_shape;
attribute vec3 position;
attribute vec2 texcoord;
varying vec3 v_position;
varying vec2 v_texcoord;
void main()
{
float z = height*Bicubic(data, data_shape, texcoord).r;
gl_Position = <transform>;
v_texcoord = texcoord;
v_position = vec3(position.xy, z);
}
"""
fragment = """
#include "misc/spatial-filters.frag"
uniform mat4 model;
uniform mat4 view;
uniform mat4 normal;
uniform sampler2D texture;
uniform float height;
uniform vec4 color;
uniform sampler2D data;
uniform vec2 data_shape;
uniform vec3 light_color[3];
uniform vec3 light_position[3];
varying vec3 v_position;
varying vec2 v_texcoord;
float lighting(vec3 v_normal, vec3 light_position)
{
// Calculate normal in world coordinates
vec3 n = normalize(normal * vec4(v_normal,1.0)).xyz;
// Calculate the location of this fragment (pixel) in world coordinates
vec3 position = vec3(view * model * vec4(v_position, 1));
// Calculate the vector from this pixels surface to the light source
vec3 surface_to_light = light_position - position;
// Calculate the cosine of the angle of incidence (brightness)
float brightness = dot(n, surface_to_light) /
(length(surface_to_light) * length(n));
brightness = max(min(brightness,1.0),0.0);
return brightness;
}
void main()
{
mat4 model = <transform.trackball_model>;
// Extract data value
float value = Bicubic(data, data_shape, v_texcoord).r;
// Compute surface normal using neighbour values
float hx0 = height*Bicubic(data, data_shape, v_texcoord+vec2(+1,0)/data_shape).r;
float hx1 = height*Bicubic(data, data_shape, v_texcoord+vec2(-1,0)/data_shape).r;
float hy0 = height*Bicubic(data, data_shape, v_texcoord+vec2(0,+1)/data_shape).r;
float hy1 = height*Bicubic(data, data_shape, v_texcoord+vec2(0,-1)/data_shape).r;
vec3 dx = vec3(2.0/data_shape.x,0.0,hx0-hx1);
vec3 dy = vec3(0.0,2.0/data_shape.y,hy0-hy1);
vec3 v_normal = normalize(cross(dx,dy));
// Map value to rgb color
float c = 0.6 + 0.4*texture2D(texture, v_texcoord).r;
vec4 l1 = vec4(light_color[0] * lighting(v_normal, light_position[0]), 1);
vec4 l2 = vec4(light_color[1] * lighting(v_normal, light_position[1]), 1);
vec4 l3 = vec4(light_color[2] * lighting(v_normal, light_position[2]), 1);
gl_FragColor = color * vec4(c,c,c,1) * (0.5 + 0.5*(l1+l2+l3));
} """
def func3(x, y):
return (1 - x / 2 + x ** 5 + y ** 3) * np.exp(-(x ** 2) - y ** 2)
class layout:
def setup(self, window):
self.window = window
self.window.resize(width, height)
self.dialogue = QtGui.QTextEdit()
self.plot = pg.GraphicsLayoutWidget(self.window)
self.plot1 = self.plot.addPlot(colspan=1)
self.glumpy_window = glumpy_app.Window(color=(1, 1, 1, 1))
self.glumpy_window._native_window
self.centralwidget = QtGui.QWidget(self.window)
self.horizontallayout = QtGui.QHBoxLayout(self.centralwidget)
self.window.setCentralWidget(self.centralwidget)
self.horizontallayout.addWidget(self.dialogue, stretch=1)
self.horizontallayout.addWidget(self.plot, stretch=1)
self.horizontallayout.addWidget(self.glumpy_window._native_window, stretch=1)
class Window(pg.Qt.QtGui.QMainWindow, layout):
def __init__(self, shot=None):
super(Window, self).__init__()
self.setup(self)
n = 64
self.surface = gloo.Program(vertex, fragment)
self.vertices, self.s_indices = primitives.plane(2.0, n=n)
self.surface.bind(self.vertices)
I = []
for i in range(n):
I.append(i)
for i in range(1, n):
I.append(n - 1 + i * n)
for i in range(n - 1):
I.append(n * n - 1 - i)
for i in range(n - 1):
I.append(n * (n - 1) - i * n)
self.b_indices = np.array(I, dtype=np.uint32).view(gloo.IndexBuffer)
x = np.linspace(-2.0, 2.0, 32).astype(np.float32)
y = np.linspace(-2.0, 2.0, 32).astype(np.float32)
X, Y = np.meshgrid(x, y)
Z = func3(X, Y)
self.surface["data"] = (Z - Z.min()) / (Z.max() - Z.min())
self.surface["data"].interpolation = gl.GL_NEAREST
self.surface["data_shape"] = Z.shape[1], Z.shape[0]
self.surface["u_kernel"] = data.get("spatial-filters.npy")
self.surface["u_kernel"].interpolation = gl.GL_LINEAR
self.surface["texture"] = data.checkerboard(32, 24)
self.transform = Trackball("vec4(position.xy, z, 1.0)")
self.surface["transform"] = self.transform
self.glumpy_window.attach(self.transform)
T = (Z - Z.min()) / (Z.max() - Z.min())
self.surface["height"] = 0.75
self.surface["light_position[0]"] = 3, 0, 0 + 5
self.surface["light_position[1]"] = 0, 3, 0 + 5
self.surface["light_position[2]"] = -3, -3, +5
self.surface["light_color[0]"] = 1, 0, 0
self.surface["light_color[1]"] = 0, 1, 0
self.surface["light_color[2]"] = 0, 0, 1
phi, theta = -45, 0
self.time = 0
self.glumpy_window.set_handler("on_init", self.on_init)
self.glumpy_window.set_handler("on_draw", self.on_draw)
def on_init(self):
gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)
gl.glPolygonOffset(1, 1)
gl.glEnable(gl.GL_LINE_SMOOTH)
gl.glLineWidth(2.5)
def on_draw(self, dt):
self.time += dt
self.glumpy_window.clear()
self.surface["data"]
gl.glDisable(gl.GL_BLEND)
gl.glEnable(gl.GL_DEPTH_TEST)
gl.glEnable(gl.GL_POLYGON_OFFSET_FILL)
self.surface["color"] = 1, 1, 1, 1
self.surface.draw(gl.GL_TRIANGLES, self.s_indices)
gl.glDisable(gl.GL_POLYGON_OFFSET_FILL)
gl.glEnable(gl.GL_BLEND)
gl.glDepthMask(gl.GL_FALSE)
self.surface["color"] = 0, 0, 0, 1
self.surface.draw(gl.GL_LINE_LOOP, self.b_indices)
gl.glDepthMask(gl.GL_TRUE)
model = self.surface["transform"]["model"].reshape(4, 4)
view = self.surface["transform"]["view"].reshape(4, 4)
self.surface["view"] = view
self.surface["model"] = model
self.surface["normal"] = np.array(np.matrix(np.dot(view, model)).I.T)
self.surface["height"] = 0.75 * np.cos(self.time)
def showEvent(self, event):
super().showEvent(event)
self.glumpy_window.dispatch_event("on_resize", *self.glumpy_window.get_size())
def closeEvent(self, event):
super().closeEvent(event)
self.glumpy_window.close()
if __name__ == "__main__":
app = pg.Qt.QtGui.QApplication([])
w = Window()
w.show()
glumpy_app.run()

Using a media/gif as a texture in rotating cube with vispy

I am using Vispy to rotate a cube. I can use imageio to use a custom texture in the face of the rotating cube successfully, but I don't understand how to use a movie or gif image.
Full source code:
import numpy as np
from vispy import gloo, app
from vispy.gloo import Program, VertexBuffer, IndexBuffer
from vispy.util.transforms import perspective, translate, rotate
from vispy.geometry import create_cube
import imageio
im = imageio.imread('C:\\vhosts\\VIDEO_TWO_CLONE\\shape.jpg')
vertex = """
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
uniform sampler2D texture;
attribute vec3 position;
attribute vec2 texcoord;
attribute vec3 normal;
attribute vec4 color;
varying vec2 v_texcoord;
void main()
{
gl_Position = projection * view * model * vec4(position,1.0);
v_texcoord = texcoord;
}
"""
fragment = """
uniform sampler2D texture;
varying vec2 v_texcoord;
void main()
{
gl_FragColor = texture2D(texture, v_texcoord);
}
"""
def checkerboard(grid_num=8, grid_size=32):
row_even = grid_num // 2 * [0, 1]
row_odd = grid_num // 2 * [1, 0]
Z = np.row_stack(grid_num // 2 * (row_even, row_odd)).astype(np.uint8)
return 255 * Z.repeat(grid_size, axis=0).repeat(grid_size, axis=1)
class Canvas(app.Canvas):
def __init__(self):
app.Canvas.__init__(self, size=(750, 750), title='Textured cube',
keys='interactive')
self.timer = app.Timer('auto', self.on_timer)
# Build cube data
V, I, _ = create_cube()
vertices = VertexBuffer(V)
self.indices = IndexBuffer(I)
# Build program
self.program = Program(vertex, fragment)
self.program.bind(vertices)
# Build view, model, projection & normal
view = translate((0, 0, -5))
model = np.eye(4, dtype=np.float32)
self.program['model'] = model
self.program['view'] = view
self.program['texture'] = im # checkerboard()
self.activate_zoom()
self.phi, self.theta = 0, 0
# OpenGL initalization
gloo.set_state(clear_color=(0.30, 0.30, 0.35, 1.00), depth_test=True)
self.timer.start()
self.show()
def on_draw(self, event):
gloo.clear(color=True, depth=True)
self.program.draw('triangles', self.indices)
def on_resize(self, event):
self.activate_zoom()
def activate_zoom(self):
gloo.set_viewport(0, 0, *self.physical_size)
projection = perspective(45.0, self.size[0] / float(self.size[1]),
2.0, 10.0)
self.program['projection'] = projection
def on_timer(self, event):
self.theta += .5
self.phi += .5
self.program['model'] = np.dot(rotate(self.theta, (0, 1, 0)),
rotate(self.phi, (0, 1, 0)))
self.update()
if __name__ == '__main__':
c = Canvas()
app.run()

A gif or a movie is essentially many image frames, coming one after the other.
What you would need to do is read the images from the GIF into an array containing the RGB(A) values of each image (for GIF, you can use the code from e.g. https://gist.github.com/BigglesZX/4016539), and then advance self.program['texture'] to the next frame of the GIF in on_timer.
In case you want to loop the texture, you could use the modulo operator %, so you don't run over the array boundaries, with something like
# gif_array is the array populated with GIF frames
self.program['texture'] = gif_array[index % (len(gif_array) - 1)]
index = index + 1

PyQtGraph get color of pixel being moused over

I have some code very similar to the example given by PyQtGraph below. I also want to add to the label the color of the exact pixel being moused over (the pixel at the crosshair). How would I do this?
import numpy as np
import pyqtgraph as pg
from pyqtgraph.Qt import QtGui, QtCore
from pyqtgraph.Point import Point
#generate layout
app = QtGui.QApplication([])
win = pg.GraphicsWindow()
win.setWindowTitle('pyqtgraph example: crosshair')
label = pg.LabelItem(justify='right')
win.addItem(label)
p1 = win.addPlot(row=1, col=0)
p2 = win.addPlot(row=2, col=0)
region = pg.LinearRegionItem()
region.setZValue(10)
# Add the LinearRegionItem to the ViewBox, but tell the ViewBox to exclude this
# item when doing auto-range calculations.
p2.addItem(region, ignoreBounds=True)
#pg.dbg()
p1.setAutoVisible(y=True)
#create numpy arrays
#make the numbers large to show that the xrange shows data from 10000 to all the way 0
data1 = 10000 + 15000 * pg.gaussianFilter(np.random.random(size=10000), 10) + 3000 * np.random.random(size=10000)
data2 = 15000 + 15000 * pg.gaussianFilter(np.random.random(size=10000), 10) + 3000 * np.random.random(size=10000)
p1.plot(data1, pen="r")
p1.plot(data2, pen="g")
p2.plot(data1, pen="w")
def update():
region.setZValue(10)
minX, maxX = region.getRegion()
p1.setXRange(minX, maxX, padding=0)
region.sigRegionChanged.connect(update)
def updateRegion(window, viewRange):
rgn = viewRange[0]
region.setRegion(rgn)
p1.sigRangeChanged.connect(updateRegion)
region.setRegion([1000, 2000])
#cross hair
vLine = pg.InfiniteLine(angle=90, movable=False)
hLine = pg.InfiniteLine(angle=0, movable=False)
p1.addItem(vLine, ignoreBounds=True)
p1.addItem(hLine, ignoreBounds=True)
vb = p1.vb
def mouseMoved(evt):
pos = evt[0] ## using signal proxy turns original arguments into a tuple
if p1.sceneBoundingRect().contains(pos):
mousePoint = vb.mapSceneToView(pos)
index = int(mousePoint.x())
#######
GET THE PIXEL COLOR AND ADD TO LABEL??? HOW?
#######
if index > 0 and index < len(data1):
label.setText("<span style='font-size: 12pt'>x=%0.1f, <span style='color: red'>y1=%0.1f</span>, <span style='color: green'>y2=%0.1f</span>" % (mousePoint.x(), data1[index], data2[index]))
vLine.setPos(mousePoint.x())
hLine.setPos(mousePoint.y())
proxy = pg.SignalProxy(p1.scene().sigMouseMoved, rateLimit=60, slot=mouseMoved)
#p1.scene().sigMouseMoved.connect(mouseMoved)
## Start Qt event loop unless running in interactive mode or using pyside.
if __name__ == '__main__':
import sys
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui.QApplication.instance().exec_()

You must override the mouseMoveEvent method, record the widget and get the pixel.
For this we will create a class that inherits from pg.GraphicsWindow:
class MyGraphicsWindow(pg.GraphicsWindow):
def __init__(self, parent=None):
pg.GraphicsWindow.__init__(self, parent=parent)
self.setMouseTracking(True)
def mouseMoveEvent(self, e):
image = QtGui.QPixmap.grabWidget(self).toImage()
color = QtGui.QColor(image.pixel(e.pos()))
print(color.name())
print("red:{}, green:{}, blue:{}".format(color.red(), color.green(), color.blue()))
pg.GraphicsWindow.mouseMoveEvent(self, e)
Then we will replace win = pg.GraphicsWindow() with win = MyGraphicsWindow()
Complete code:
class MyGraphicsWindow(pg.GraphicsWindow):
def __init__(self, parent=None):
pg.GraphicsWindow.__init__(self, parent=parent)
self.setMouseTracking(True)
def mouseMoveEvent(self, e):
image = QtGui.QPixmap.grabWidget(self).toImage()
color = QtGui.QColor(image.pixel(e.pos()))
print(color.name())
print("{}, {}, {}".format(color.red(), color.green(), color.blue()))
pg.GraphicsWindow.mouseMoveEvent(self, e)
#generate layout
app = QtGui.QApplication(sys.argv)
win = MyGraphicsWindow()
win.setWindowTitle('pyqtgraph example: crosshair')
label = pg.LabelItem(justify='right')
win.addItem(label)
p1 = win.addPlot(row=1, col=0)
p2 = win.addPlot(row=2, col=0)
region = pg.LinearRegionItem()
region.setZValue(10)
# Add the LinearRegionItem to the ViewBox, but tell the ViewBox to exclude this
# item when doing auto-range calculations.
p2.addItem(region, ignoreBounds=True)
#pg.dbg()
p1.setAutoVisible(y=True)
#create numpy arrays
#make the numbers large to show that the xrange shows data from 10000 to all the way 0
data1 = 10000 + 15000 * pg.gaussianFilter(np.random.random(size=10000), 10) + 3000 * np.random.random(size=10000)
data2 = 15000 + 15000 * pg.gaussianFilter(np.random.random(size=10000), 10) + 3000 * np.random.random(size=10000)
p1.plot(data1, pen="r")
p1.plot(data2, pen="g")
p2.plot(data1, pen="w")
def update():
region.setZValue(10)
minX, maxX = region.getRegion()
sys.exit(app.exec_())

Painting on a widget that contains a QGridLayout in PySide/PyQt

I am making a custom QWidget in which I have a QGridLayout, and draw a rectangle on a particular element in the grid. I also manually draw lines to delineate the location of the grid elements (with QPainter.DrawLines).
After drawing the lines, I then paint the rectangle within one of the grid elements, with its location specified using the QGridLayout coordinate system .
The problem is, the rectangle does not stay confined to its grid element. For instance, in the example below, the blue rectangle and black grid lines get out of alignment, so I end up with a blue box floating around in space.
I have not found explicit discussion of this issue via Google or SO.
Edit:
Note as pointed out in the accepted answer, the mistake was using grid coordinates to draw on the grid, when I should have been using point coordinates (i.e., column, row). That is, the mistake in the code below is that the element in the grid has its x- and y- coordinates reversed.
from PySide import QtGui, QtCore
class HighlightSquare(QtGui.QWidget):
def __init__(self, parent = None):
QtGui.QWidget.__init__(self, parent=None)
self.setSizePolicy(QtGui.QSizePolicy(QtGui.QSizePolicy.Expanding,
QtGui.QSizePolicy.Expanding))
self.setMinimumSize(self.minimumSizeHint())
layout = QtGui.QGridLayout()
layout.addItem(QtGui.QSpacerItem(10,10), 0, 0)
layout.addItem(QtGui.QSpacerItem(10,10), 0, 1)
layout.addItem(QtGui.QSpacerItem(10,10), 1, 0)
layout.addItem(QtGui.QSpacerItem(10,10), 1, 1)
self.setLayout(layout)
self.resize(150, 150)
self.update()
def paintEvent(self, event = None):
painter = QtGui.QPainter(self)
painter.setRenderHint(QtGui.QPainter.Antialiasing)
winHeight=self.size().height(); heightStep=winHeight/2
winWidth=self.size().width(); widthStep=winWidth/2
#Draw lines
painter.setPen(QtCore.Qt.black)
for i in range(4):
#vertical lines
painter.drawLine(QtCore.QPoint(i*widthStep,0), QtCore.QPoint(i*widthStep, winHeight))
#horizontal lines
painter.drawLine(QtCore.QPoint(0,heightStep*i), QtCore.QPoint(winWidth, heightStep*i))
#Draw blue outline around box 1,1
highlightCoordinate=(1,1)
pen=QtGui.QPen(QtCore.Qt.blue, 3)
painter.setPen(pen)
coordHighlight=[QtCore.QPoint(highlightCoordinate[1]*heightStep, highlightCoordinate[0]*widthStep),\
QtCore.QPoint(highlightCoordinate[1]*heightStep, (highlightCoordinate[0]+1)*widthStep),\
QtCore.QPoint((highlightCoordinate[1]+1)*heightStep, (highlightCoordinate[0]+1)*widthStep),\
QtCore.QPoint((highlightCoordinate[1]+1)*heightStep, highlightCoordinate[0]*widthStep),\
QtCore.QPoint(highlightCoordinate[1]*heightStep, highlightCoordinate[0]*widthStep)]
#print coordHighlight
painter.drawPolyline(coordHighlight)
def minimumSizeHint(self):
return QtCore.QSize(120,120)
if __name__=="__main__":
import sys
app=QtGui.QApplication(sys.argv)
myLight = HighlightSquare()
myLight.show()
sys.exit(app.exec_())

Have you read the definition of the constructor of class QtCore.QPoint? At method QPoint.__init__ (self, int xpos, int ypos) your code is reversed (ypos, xpos). I fixed it.
import sys
from PyQt4 import QtGui, QtCore
class QHighlightSquareWidget (QtGui.QWidget):
def __init__ (self, parent = None):
QtGui.QWidget.__init__(self, parent = None)
self.setSizePolicy (
QtGui.QSizePolicy (
QtGui.QSizePolicy.Expanding,
QtGui.QSizePolicy.Expanding))
self.setMinimumSize(self.minimumSizeHint())
allQGridLayout = QtGui.QGridLayout()
allQGridLayout.addItem(QtGui.QSpacerItem(10,10), 0, 0)
allQGridLayout.addItem(QtGui.QSpacerItem(10,10), 0, 1)
allQGridLayout.addItem(QtGui.QSpacerItem(10,10), 1, 0)
allQGridLayout.addItem(QtGui.QSpacerItem(10,10), 1, 1)
self.setLayout(allQGridLayout)
self.resize(150, 150)
self.update()
def paintEvent (self, eventQPaintEvent):
myQPainter = QtGui.QPainter(self)
myQPainter.setRenderHint(QtGui.QPainter.Antialiasing)
winHeight = self.size().height()
heightStep = winHeight / 2
winWidth = self.size().width()
widthStep = winWidth / 2
myQPainter.setPen(QtCore.Qt.black)
for i in range(4):
myQPainter.drawLine(QtCore.QPoint(i * widthStep, 0 ), QtCore.QPoint(i * widthStep, winHeight ))
myQPainter.drawLine(QtCore.QPoint(0, heightStep * i), QtCore.QPoint(winWidth, heightStep * i))
highlightCoordinate = (1, 1)
myQPen = QtGui.QPen(QtCore.Qt.blue, 3)
myQPainter.setPen(myQPen)
coordHighlight = [
QtCore.QPoint( highlightCoordinate[0] * widthStep, highlightCoordinate[1] * heightStep),
QtCore.QPoint((highlightCoordinate[0] + 1) * widthStep, highlightCoordinate[1] * heightStep),
QtCore.QPoint((highlightCoordinate[0] + 1) * widthStep, (highlightCoordinate[1] + 1) * heightStep),
QtCore.QPoint( highlightCoordinate[0] * widthStep, (highlightCoordinate[1] + 1) * heightStep),
QtCore.QPoint( highlightCoordinate[0] * widthStep, highlightCoordinate[1] * heightStep)]
myQPainter.drawPolyline(*coordHighlight)
def minimumSizeHint (self):
return QtCore.QSize(120, 120)
if __name__=="__main__":
myQApplication = QtGui.QApplication(sys.argv)
myQHighlightSquareWidget = QHighlightSquareWidget()
myQHighlightSquareWidget.show()
sys.exit(myQApplication.exec_())