Makro Nakresli kružnici ze 3 bodů ve 3D

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Revision as of 17:44, 4 February 2014 by Honza32 (talk | contribs) (Created page with "{{Macro|Icon=Macro_Draft_Circle_3_Points|Name=Macro_Draft_Circle_3_Points_3D|Description=Vytváří kružnici ze 3 bodů v prostoru.|Author=galou_breizh}}")

File:Macro Draft Circle 3 Points Macro_Draft_Circle_3_Points_3D

Description
Vytváří kružnici ze 3 bodů v prostoru.

Author: galou_breizh
Author
galou_breizh
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Macro Version
1.0
Date last modified
None
FreeCAD Version(s)
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This macro creates a circle on 3 selected points in the space. The points can be objects such as cubes, cylinder, then selected coordinates will be the centre of these forms.


Use

Select 3 points, or forms in the 3D view and run the macro.
If the shape is a line, the coordinate will be the center of the line.

Limits

The order of selection of fear forms influencing the AXIS angle and reverse the inclination of the circle. In this case, reverse or change the order of selection of the shapes.
The coordinates X, Y, Z of value 0 or alignment not allowing not calculating, can return a division by zero error, and translated as "The three points are aligned"

Script

# -*- coding: utf-8 -*-
# Create a circle from 3 points selected on the X, Y, Z map
# 04/03/2013
# From http://en.wikipedia.org/wiki/Circumscribed_circle

from math import pi, asin
import Draft, FreeCAD, FreeCADGui
from FreeCAD import Base
from PyQt4 import QtCore, QtGui

def errorDialog(msg):
    # Create a simple dialog QMessageBox
    # The first argument indicates the icon used: one of QtGui.QMessageBox.{NoIcon, Information, Warning, Critical, Question} 
    diag = QtGui.QMessageBox(QtGui.QMessageBox.Critical,u"Error Message",msg)
    diag.setWindowModality(QtCore.Qt.ApplicationModal)
    diag.exec_()

def affiche(x,y,z,r,angle):
    diag = QtGui.QMessageBox(QtGui.QMessageBox.Information,u"Coordinates",u"Coordinate X : "+str(x)+"\r\n"+u"Coordinate Y : "+str(y)+"\n"+u"Coordinate Z : "+str(z)+"\nRadius\t   : "+str(r)+"\nAngle\t   : "+str(angle))
    diag.setWindowModality(QtCore.Qt.ApplicationModal)
    diag.setWindowModality(QtCore.Qt.NonModal)
    diag.exec_()

# objects selected
sel = FreeCADGui.Selection.getSelection()
# If there are 3 selected points so...
if len(sel)==3 :
    # Assignment of variables
    P1 = sel[0].Shape.BoundBox.Center
    P2 = sel[1].Shape.BoundBox.Center
    P3 = sel[2].Shape.BoundBox.Center

    P1P2 = (P2 - P1).Length
    P2P3 = (P3 - P2).Length
    P3P1 = (P1 - P3).Length

    # Circle radius.
    l = ((P1 - P2).cross(P2 - P3)).Length
    try:
        #if l < 1e-8:
        #    errorDialog("The three points are aligned")
        r = P1P2 * P2P3 * P3P1 / 2 / l
    except:
        errorDialog("The three points are aligned")
    else:
        # Sphere center.
        a = P2P3**2 * (P1 - P2).dot(P1 - P3) / 2 / l**2
        b = P3P1**2 * (P2 - P1).dot(P2 - P3) / 2 / l**2
        c = P1P2**2 * (P3 - P1).dot(P3 - P2) / 2 / l**2
        P1.multiply(a)
        P2.multiply(b)
        P3.multiply(c)
        PC = P1 + P2 + P3

        # Creation of a circle
        pl = Base.Placement()
        v = (P1 - P2).cross(P3 - P2)
        v.normalize()
        axis = Base.Vector(0, 0, 1).cross(v)
        angle = asin(axis.Length) * 180 / pi
        axis.normalize()
        pl = Base.Placement(PC, axis, angle)
        Draft.makeCircle(r, placement=pl, face=False, support=None)
        # Displays the result in the windows
        affiche((PC.x),(PC.y),(PC.z),r,angle)
        # Displays the result in the FreeCAD report view
        #FreeCAD.Console.PrintMessage("Coordinate X : "+str(PC.x)+"\n")
        #FreeCAD.Console.PrintMessage("Coordinate Y : "+str(PC.y)+"\n")
        #FreeCAD.Console.PrintMessage("Coordinate Z : "+str(PC.z)+"\n")
        #FreeCAD.Console.PrintMessage("Radius       : "+str(r)+"\n")
        #FreeCAD.Console.PrintMessage("Angle        : "+str(angle)+"\n")
else:
    # If the condition is not met, repeat
    #FreeCAD.Console.PrintError("Select 3 points and repeat\n")
    errorDialog("Select 3 points and repeat\n")
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