OpenCASCADE et le soleil invisible de Tao

Le meilleur voyageur qui ne laisse aucune trace

Le meilleur chef qui inspire sans parler

Le plan est parfait, s'il n'y a pas de plan du tout

Et si un sage ferme la porte,

vous ne découvrirez jamais le secret.

Le Grand Livre du Tao - Verset 27 (Traduction par Y. Polezhaeva)

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#initMode = 'screen','web','stl'
def ScInit(initMode, decoration, precision, exportDir):
  pass

#default styles
#'stInfo' - for service objects
#'stMain' - for main object of drawing
#'stFocus' - for important details
def ScStyle(styleVal):
  pass

#draw objects
def ScPoint(pnt, style):
  pass
def ScLine(pnt1, pnt2, style):
  pass
def ScCircle(pnt1, pnt2, pnt3, style):
  pass
def ScShape(shape, style):
  pass
def ScLabel(pnt, text, style):
  pass

#start render
def ScStart()    

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3. OpenCASCADE

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def getPntsBase(r):
    
    r2 = r/2
    
    gpPntMinC = gp_Pnt(0,r2,0)
    
    p0 = gp_Pnt(0,0,0)      
    p1 = getPntRotate(gpPntMinC , p0, -pi/4)      
    p2 = gp_Pnt(-r2,r2,0)      
    p3 = getPntRotate(gpPntMinC , p0, -pi/4*3)      
    p4 = gp_Pnt(0,r,0)      
    p5 = gp_Pnt(r,0,0)      
    p6 = gp_Pnt(0,-r,0)      
    p7 = gp_Pnt(r2,-r2,0)      
    
    return p0, p1, p2, p3, p4, p5, p6, p7
  
def getWireDaoClassic(ppBase):
    
    p0, p1, p2, p3, p4, p5, p6, p7  = ppBase
    
    arc1 =  GC_MakeArcOfCircle(p0,p1,p2).Value()
    arc2 =  GC_MakeArcOfCircle(p2,p3,p4).Value()
    arc3 =  GC_MakeArcOfCircle(p4,p5,p6).Value()
    arc4 =  GC_MakeArcOfCircle(p6,p7,p0).Value()
 
    edge1 = BRepBuilderAPI_MakeEdge(arc1).Edge()
    edge2 = BRepBuilderAPI_MakeEdge(arc2).Edge()
    edge3 = BRepBuilderAPI_MakeEdge(arc3).Edge()
    edge4 = BRepBuilderAPI_MakeEdge(arc4).Edge()
  
    shape =  BRepBuilderAPI_MakeWire(edge1, edge2, edge3, edge4).Wire()
    
    return shape
 
def slide_01_DaoClassic(r):
    
    drawCircle(r, 'stInfo')
    pntsBase = getPntsBase(r)
    drawPoints(pntsBase, 'stFocus', 'b')
    shapeDaoClassic = getWireDaoClassic(pntsBase)
    ScShape(shapeDaoClassic, 'stMain')

WebGL-: 01

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def getShapeOffset(shape, offset):
    tool = BRepOffsetAPI_MakeOffset()
    tool.AddWire(shape)
    tool.Perform(offset)
    shape = tool.Shape()  
    return shape

def slide_02_DaoConcept(r, offset):
    
    drawCircle(r + offset, 'stInfo')
    pntsBase = getPntsBase(r)
    wireDaoClassic = getWireDaoClassic(pntsBase)
    wireDao0 = getShapeOffset(wireDaoClassic, -offset)
    ScShape(wireDao0, 'stMain')
  
    pntsDao0 = getPntsOfShape(wireDao0)
    drawPoints(pntsDao0, 'stFocus', 'd')
  
    wireDao1 = getShapeOZRotate(wireDao0, pi)
    ScShape(wireDao1, 'stInfo')

WebGL-: 02

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def getPntDaoFocus(r):
    return gp_Pnt(0,-r/4,0)


def getPntsForDaoSec(pntDaoStart, pntUpLimit, pntDaoEnd, pntDownLimit, pntFocus, k):
    angleLimit = 0
    pntLimit = getPntScale(pntFocus, pntUpLimit, 1.2)
    angleStart = getAngle(pntFocus, pntLimit, pntDaoStart)
    angleEnd = getAngle(pntFocus, pntLimit, pntDaoEnd)
    kLimit = (angleLimit - angleStart)/(angleEnd - angleStart)
    if k < kLimit: #head
        kHead = (k - 0) / (kLimit- 0)
        xStart = pntUpLimit.X()
        xEnd = pntDaoStart.X()
        dx = (xEnd-xStart)*(1 - kHead)
        pnt0 = getPntTranslate(pntFocus, dx, 0, 0)
        pnt1 = getPntTranslate(pntLimit, dx, 0, 0)
    else: #tail    
        kTail = (k - kLimit) / (1 - kLimit)
        angle = -angleEnd*kTail
        pnt0 = pntFocus
        pnt1 = getPntRotate(pntFocus, pntLimit, angle)
    return pnt0, pnt1


def getWireDaoSec(shapeDao, pntFocus, k):
    
    pntsDao = getPntsOfShape(shapeDao)
    pntDownLimit, pntDaoStart, pntUpLimit, pntDaoEnd = pntsDao
    
    p1, p2 = getPntsForDaoSec(pntDaoStart, pntUpLimit, pntDaoEnd, pntDownLimit, 
                              pntFocus, k)
    sectionPlane = getFacePlane(p1, p2, 3)
    
    pnt0, pnt1 =  getPntsEdgesFacesIntersect(shapeDao, sectionPlane)
    pntUp = getPntSectionUp(pnt0, pnt1)
    circle = GC_MakeCircle(pnt0, pntUp, pnt1).Value()
    edge = BRepBuilderAPI_MakeEdge(circle).Edge()
    wire =  BRepBuilderAPI_MakeWire(edge).Wire()
    return wire

   
def slide_03_DaoSecPrincipe(r, offset, k, h):
    
    drawCircle(r + offset,  'stInfo')
    pntsBase = getPntsBase(r)
    wireDaoClassic = getWireDaoClassic(pntsBase)
    wireDao0 = getShapeOffset(wireDaoClassic, -offset)
    ScShape(wireDao0, 'stMain')
    
    # for oure goal we need divide Dao on Head and Tail
    # Head sections is parallell
    # Tail sections is focused on focus point
    pntsDao0 = getPntsOfShape(wireDao0)
    pntDownLimit, pntDaoStart, pntUpLimit, pntDaoEnd  = pntsDao0
    
    # we need focus to determine tail sections 
    pntFocus = getPntDaoFocus(r)
    ScPoint(pntFocus, 'stMain')
    ScLabel(pntFocus, 'F' ,'stMain')
    
    # we need two points to determine section
    pnt1, pnt2 = getPntsForDaoSec(pntDaoStart, pntUpLimit, pntDaoEnd, 
                                  pntDownLimit, pntFocus, k)
    ScLine(pnt1, pnt2, 'stFocus')
    
    # !!! we need use plane to detect intercsect (not line) becouse 3D
    planeSec = getFacePlane(pnt1, pnt2, h)
    ScShape(planeSec, 'stFocus')

    pntsSec =  getPntsEdgesFacesIntersect(wireDao0, planeSec)
    drawPoints(pntsSec, 'stFocus')
    
    wireSec = getWireDaoSec(wireDao0, pntFocus, k)
    ScShape(wireSec, 'stFocus') 

WebGL-: 03

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def slide_04_DaoManySec(r, offset, kStart, kEnd, cnt):
    
    drawCircle(r + offset, 'stInfo')
    pntsBase = getPntsBase(r)
    wireDaoClassic = getWireDaoClassic(pntsBase)
    wireDao0 = getShapeOffset(wireDaoClassic, -offset)
    ScShape(wireDao0, 'stMain')
    
    pntsDao0 = getPntsOfShape(wireDao0)
    pntDownLimit, pntDaoStart, pntUpLimit, pntDaoEnd  = pntsDao0
    
    pntFocus = getPntDaoFocus(r)
    
    for i in range(cnt+1):
        k = i/cnt
        kkScale = kEnd - kStart
        kk = kStart + k* kkScale
        p0,p1 = getPntsForDaoSec(pntDaoStart, pntUpLimit, pntDaoEnd, 
        pntDownLimit, pntFocus, kk)
        ScLine(p0, p1, 'stFocus')
        wireSec = getWireDaoSec(wireDao0, pntFocus, kk)
        ScShape(wireSec, 'stMain') 

WebGL-: 04

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def slide_05_DaoSkinning (r, offset):
    
    drawCircle(r + offset,  'stInfo')
    pntsBase = getPntsBase(r)
    wireDaoClassic = getWireDaoClassic(pntsBase)
    wireDao0 = getShapeOffset(wireDaoClassic, -offset)
    ScShape(wireDao0, 'stMain')
    
    pntsDao0 = getPntsOfShape(wireDao0)
    pntDownLimit, pntDaoStart, pntUpLimit, pntDaoEnd  = pntsDao0
    
    pntFocus = getPntDaoFocus(r)
    drawPoints(pntFocus, 'stMain')
  
    ks = [ 3, 9 , 16, 24, 35, 50, 70, 85] 
    wiresSec = []
 
    for k in  ks:
       wireSec = getWireDaoSec(wireDao0, pntFocus, k/100)
       ScShape(wireSec, 'stMain')
       wiresSec += [wireSec]    
    
    solidDao0 = getShapeSkin(pntDaoStart, wiresSec, pntDaoEnd)
    ScShape(solidDao0, 'stFocus')

WebGL-: 05

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def getSolidDao(r, offset):
    
    pntsBase = getPntsBase(r)
    wireDaoClassic = getWireDaoClassic(pntsBase)
    wireDao = getShapeOffset(wireDaoClassic, -offset)
    
    pntsDao = getPntsOfShape(wireDao)
    pntDownLimit, pntDaoStart, pntUpLimit, pntDaoEnd  = pntsDao
    
    pntFocus = getPntDaoFocus(r)
   
    ks = [ 3, 9 , 16, 24, 35, 50, 70, 85] 
    wiresSec = []
 
    for k in  ks:
       wireSec = getWireDaoSec(wireDao, pntFocus, k/100)
       wiresSec += [wireSec]    
    
    solidDao = getShapeSkin(pntDaoStart, wiresSec, pntDaoEnd)
    solidDao = getShapeZScale(solidDao, 0.7)
    return solidDao
   
def slide_06_DaoComplete (r, offset):
    
    solidDao0 = getSolidDao(r, offset)
    ScShape(solidDao0, stDao0)
    solidDao1  = getShapeOZRotate(solidDao0, pi)
    ScShape(solidDao1, stDao1)

WebGL-: 06

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def getDaoCase(r, offset, h):
    r2 = r*2                                    
    h2 = h/2
    rTop = r + offset
    rSphere = gp_Vec(0,rTop,h2).Magnitude()
    sphere = BRepPrimAPI_MakeSphere(rSphere).Shape()
    limit = BRepPrimAPI_MakeBox( gp_Pnt(-r2, -r2, -h2), gp_Pnt(r2, r2, h2) ).Shape()
    case = BRepAlgoAPI_Common(sphere, limit).Shape()
    case = getShapeTranslate(case, 0,0,-h2)
 
    
    solidDao0 = getSolidDao(r, offset)
    solidDao1  = getShapeOZRotate(solidDao0, pi)
   
    case = BRepAlgoAPI_Cut(case, solidDao0).Shape()
    case = BRepAlgoAPI_Cut(case, solidDao1).Shape()
  
    return case
    
def slide_07_DaoWithCase (r, offset, caseH, caseZMove ,gap):
    
    solidDao0 = getSolidDao(r, offset+gap)
    ScShape(solidDao0, stDao0)
    solidDao1  = getShapeOZRotate(solidDao0, pi)
    ScShape(solidDao1, stDao1)
    
    case = getDaoCase(r, offset, caseH)
    
    case = getShapeTranslate(case, 0,0, caseZMove)
    ScShape(case, stCase)

WebGL-: 07

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Open Source

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• makeDaoShape.py -

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Nous devons savoir quand arrêter le

navire ne peut pas être trop rempli des

valeurs grandes sont plus difficiles à garder

et une épée qui est trop forte endommageront plus vite avec un

bon rang trop fier

pour appeler

votre maison à votre maison Votre travail est terminé, donc pouvoir quitter

Tel est le sens de la force, la vie et le chemin.

Le Grand Livre du Tao - Verset 9 (Traduit par Y. Polezhaeva)