que estaba buscando desde hace tiempo para algo así, y finalmente arreglé para cocinar un ejemplo de trabajo "mínimo" con Python wx, utilizando wx.lib.ogl y sus Diagram y ShapeCanvas clases.El código (abajo) resulta con algo como esto:
Nota:
- La aplicación se inicia con el círculo añadido; presione ESPACIO para agregar rectángulos en la posición aleatoria
- Haga clic en un objeto para seleccionarlo (para mostrar los identificadores); para deseleccionarlo, haga clic en el objeto de nuevo (haciendo clic en el fondo no tiene ningún efecto) - esta es la funcionalidad de
ogl
- La cuadrícula se dibuja "manualmente"; sin embargo, la función de ajustar a la cuadrícula es
ogl
- Ajustar a la cuadrícula solo funciona automáticamente cuando se mueven las formas con la función de arrastrar del mouse; para otros fines debe llamarlo manualmente
- Ajustar a la cuadrícula, así como cambiar el tamaño de la forma por los mangos, funciona con respecto al centro de cada forma (no estoy seguro de si
ogl permite cambiar ese anclaje a, por ejemplo, abajo esquina izquierda)
el ejemplo se utiliza una clase MyPanel que hace su propio dibujo, y hereda tanto desde ogl.ShapeCanvas y desde wx.Panel (aunque el mixin con wx.Panel se puede caer, y el código seguirá funcionando de la misma) - que luego se agrega a un wx.Frame. Tenga en cuenta los comentarios del código para algunas advertencias (como el uso de ogl.ShapeCanvas bloqueando todos los eventos clave, a menos que primero se realice un SetFocus en ese widget).
El código:
import wx
import wx.lib.ogl as ogl
import random
# tested on wxPython 2.8.11.0, Python 2.7.1+, Ubuntu 11.04
# started from:
# http://stackoverflow.com/questions/25756896/drawing-to-panel-inside-of-frame-in-wxpython/27804975#27804975
# see also:
# wxPython-2.8.11.0-demo/demo/OGL.py
# https://www.daniweb.com/software-development/python/threads/186203/creating-editable-drawing-objects-in-wxpython
# http://gscept.com/svn/Docs/PSE/Milestone%203/code/trunk/python_test/src/oglEditor.py
# http://nullege.com/codes/search/wx.lib.ogl.Diagram
# http://nullege.com/codes/show/src%40w%40e%40web2cms-HEAD%40web2py%40gluon%40contrib%40pyfpdf%40designer.py/465/wx.lib.ogl.Diagram/python
# https://www.daniweb.com/software-development/python/threads/204969/setfocus-on-canvas-not-working
# http://stackoverflow.com/questions/3538769/how-do-you-draw-a-grid-and-rectangles-in-python
# http://stackoverflow.com/questions/7794496/snapping-to-pixels-in-wxpython
# ogl.ShapeCanvas must go first, else TypeError: Cannot create a consistent method resolution
class MyPanel(ogl.ShapeCanvas, wx.Panel):#(wx.PyPanel): #PyPanel also works
def __init__(self, parent, id=wx.ID_ANY, pos=wx.DefaultPosition, size=wx.DefaultSize, style=0, name="MyPanel"):
super(MyPanel, self).__init__(parent, id, pos, size, style, name)
self.gridsize = 20 # in pixels
# must have these (w. Diagram) if using ogl.ShapeCanvas:
self.diagram = ogl.Diagram()
self.SetDiagram(self.diagram)
self.diagram.SetCanvas(self)
# set up snap to grid - note, like this it works only for drag (relative to shape center), not for resize via handles!
self.diagram.SetGridSpacing(self.gridsize)
self.diagram.SetSnapToGrid(True)
# initialize array of shapes with one element
self.shapes = []
self.MyAddShape(
ogl.CircleShape(85), # diameter - drag marquee will not be visible if (diameter mod gridsize == 0), as it will overlap with the grid lines
60, 60, wx.Pen(wx.BLUE, 3), wx.GREEN_BRUSH, "Circle"
)
self.Bind(wx.EVT_SIZE, self.OnSize)
self.Bind(wx.EVT_PAINT, self.OnPaint)
wx.EVT_KEY_DOWN(self, self.OnKeyPressedM)
def OnKeyPressedM(self, event):
keyCode = event.GetKeyCode()
print("MyPanel.OnKeyPressedM: %d"%(keyCode))
# insert a rectangle here on [SPACE]:
if keyCode == wx.WXK_SPACE:
randx = random.randint(1, 300)
randy = random.randint(1, 200)
if self.diagram.GetSnapToGrid():
randx, randy = self.Snap(randx, randy) # must do snapping (if desired) manually, here at insertion!
self.MyAddShape(
ogl.RectangleShape(60, 20),
randx, randy, wx.BLACK_PEN, wx.LIGHT_GREY_BRUSH, "Rect %d"%(len(self.shapes))
)
self.Refresh(False)
event.Skip() # must have this, to have the MyFrame.OnKeyPressed trigger as well!
def OnSize(self, event):
#print("OnSize" +str(event))
self.Refresh() # must have here!
event.Skip()
def DrawBackgroundGrid(self):
dc = wx.PaintDC(self)
#print(dc)
rect = self.GetClientRect()
rx, ry, rw, rh = rect
dc.SetBrush(wx.Brush(self.GetForegroundColour()))
dc.SetPen(wx.Pen(self.GetForegroundColour()))
# draw ("tile") the grid
x = rx
while x < rx+rw:
y = ry
dc.DrawLine(x, ry, x, ry+rh) # long (vertical) lines
while y < ry+rh:
dc.DrawLine(x, y, x+self.gridsize, y) # short (horizontal) lines
y = y + self.gridsize
x = x + self.gridsize
def OnPaint(self, event):
dc = wx.PaintDC(self) # works
self.DrawBackgroundGrid()
# self.Refresh() # recurses here - don't use!
# self.diagram.GetCanvas().Refresh() # blocks here - don't use!
self.diagram.GetCanvas().Redraw(dc) # this to redraw the elements on top of the grid, drawn just before
# MyAddShape is from OGL.py:
def MyAddShape(self, shape, x, y, pen, brush, text):
# Composites have to be moved for all children to get in place
if isinstance(shape, ogl.CompositeShape):
dc = wx.ClientDC(self)
self.PrepareDC(dc)
shape.Move(dc, x, y)
else:
shape.SetDraggable(True, True)
shape.SetCanvas(self)
shape.SetX(x)
shape.SetY(y)
if pen: shape.SetPen(pen)
if brush: shape.SetBrush(brush)
if text:
for line in text.split('\n'):
shape.AddText(line)
#shape.SetShadowMode(ogl.SHADOW_RIGHT)
self.diagram.AddShape(shape)
shape.Show(True)
evthandler = MyEvtHandler(self)
evthandler.SetShape(shape)
evthandler.SetPreviousHandler(shape.GetEventHandler())
shape.SetEventHandler(evthandler)
self.shapes.append(shape)
return shape
# copyfrom OGL.pyl; modded
class MyEvtHandler(ogl.ShapeEvtHandler):
def __init__(self, parent): #
ogl.ShapeEvtHandler.__init__(self)
self.parent = parent
def UpdateStatusBar(self, shape):
x, y = shape.GetX(), shape.GetY()
width, height = shape.GetBoundingBoxMax()
self.parent.Refresh(False) # do here, to redraw the background after a drag move, or scale of shape
print("Pos: (%d, %d) Size: (%d, %d)" % (x, y, width, height))
def OnLeftClick(self, x, y, keys=0, attachment=0):
# note: to deselect a selected shape, don't click the background, but click the shape again
shape = self.GetShape()
canvas = shape.GetCanvas()
dc = wx.ClientDC(canvas)
canvas.PrepareDC(dc)
if shape.Selected():
shape.Select(False, dc)
#canvas.Redraw(dc)
canvas.Refresh(False)
else:
redraw = False
shapeList = canvas.GetDiagram().GetShapeList()
toUnselect = []
for s in shapeList:
if s.Selected():
# If we unselect it now then some of the objects in
# shapeList will become invalid (the control points are
# shapes too!) and bad things will happen...
toUnselect.append(s)
shape.Select(True, dc)
if toUnselect:
for s in toUnselect:
s.Select(False, dc)
##canvas.Redraw(dc)
canvas.Refresh(False)
self.UpdateStatusBar(shape)
def OnEndDragLeft(self, x, y, keys=0, attachment=0):
shape = self.GetShape()
ogl.ShapeEvtHandler.OnEndDragLeft(self, x, y, keys, attachment)
if not shape.Selected():
self.OnLeftClick(x, y, keys, attachment)
self.UpdateStatusBar(shape)
def OnSizingEndDragLeft(self, pt, x, y, keys, attch):
ogl.ShapeEvtHandler.OnSizingEndDragLeft(self, pt, x, y, keys, attch)
self.UpdateStatusBar(self.GetShape())
def OnMovePost(self, dc, x, y, oldX, oldY, display):
shape = self.GetShape()
ogl.ShapeEvtHandler.OnMovePost(self, dc, x, y, oldX, oldY, display)
self.UpdateStatusBar(shape)
if "wxMac" in wx.PlatformInfo:
shape.GetCanvas().Refresh(False)
def OnRightClick(self, *dontcare):
#self.log.WriteText("%s\n" % self.GetShape())
print("OnRightClick")
class MyFrame(wx.Frame):
def __init__(self, parent):
wx.Frame.__init__(self, parent, -1, "Custom Panel Grid Demo")
# This creates some pens and brushes that the OGL library uses.
# (else "global name 'BlackForegroundPen' is not defined")
# It should be called after the app object has been created, but
# before OGL is used.
ogl.OGLInitialize()
self.SetSize((300, 200))
self.panel = MyPanel(self) #wx.Panel(self)
self.panel.SetBackgroundColour(wx.Colour(250,250,250))
self.panel.SetForegroundColour(wx.Colour(127,127,127))
sizer_1 = wx.BoxSizer(wx.HORIZONTAL)
sizer_1.Add(self.panel, 1, wx.EXPAND | wx.ALL, 0)
self.SetSizer(sizer_1)
self.SetAutoLayout(1)
self.Layout()
self.Show(1)
# NOTE: on my dev versions, using ogl.Diagram causes _all_
# key press events, from *anywhere*, to stop propagating!
# Doing a .SetFocus on the ogl.ShapeCanvas panel,
# finally makes the Key events propagate!
# (troubleshoot via run.py from wx python demo)
self.panel.SetFocus()
self.Bind(wx.EVT_CHAR_HOOK, self.OnKeyPressed) # EVT_CHAR_HOOK EVT_KEY_DOWN
def OnKeyPressed(self, event):
print("MyFrame.OnKeyPressed (just testing)")
app = wx.App(0)
frame = MyFrame(None)
app.SetTopWindow(frame)
frame.Show()
app.MainLoop()
El ejemplo de DiagramScene repite una imagen para crear una cuadrícula. Puede o no ser difícil encajar objetos en una cuadrícula de este tipo. –
Eso es cierto, tal vez sea mejor crear una cuadrícula de cuadrados. Lo hago en una de mis aplicaciones usando un QGraphicsItemGroup con cada celda de la cuadrícula que pertenece al grupo. –