CadQuery OCC FUSE Hash Testing with Output of New Faces

cq_occ_fuse_hash_testing.py

import cadquery as cq
from random import randrange as rrr
from random import seed
seed(10) #set seed for consistent colors
from OCP.BRepPrimAPI import (
    BRepPrimAPI_MakePrism,
)

from OCP.BRepAlgoAPI import (
    BRepAlgoAPI_Common,
    BRepAlgoAPI_Fuse,
    BRepAlgoAPI_Cut,
    BRepAlgoAPI_BooleanOperation,
)
from OCP.TopTools import TopTools_IndexedDataMapOfShapeListOfShape, TopTools_ListOfShape
from OCP.TopExp import TopExp_Explorer  # Toplogy explorer

layer1 = cq.Workplane("XY").box(80, 60, 20)
layer2 = (cq.Workplane("XY")
              .workplane(offset=10)
              .box(60,40,20)
              )

print(40*"#"+"\n")#run separator

def rnco(): return rrr(10,100),rrr(10,100),rrr(10,100) #random color, dont want too bright

HASH_UPPER_BOUND = 2147483647
def dump_occ_obj(occ_obj, name="something"):
    r = []
    r.append("Dumping: " + name)
    o = cq.Shape.cast(occ_obj)
    #DISABLE vertices and edges for now
    #r.append("Vertices::")
    #for v in o.Vertices():
    #   r.append("\t" + str(v.wrapped.HashCode(HASH_UPPER_BOUND)))
    
    #r.append("Edges::")       
    #for e in o.Edges():
    #   r.append("\t" + str(e.wrapped.HashCode(HASH_UPPER_BOUND)))
    
    r.append("Faces::")       
    for f in o.Faces():
        r.append("\t" + str(f.wrapped.HashCode(HASH_UPPER_BOUND)))
    print("\n".join(r))

def occ_native_fuse(to_add1, to_add2):
    def list_of_one_shape(s):
        rv = TopTools_ListOfShape()
        rv.Append(s)
        return rv    
    fuse_op = BRepAlgoAPI_Fuse()
    fuse_op.SetArguments( list_of_one_shape(to_add1))
    fuse_op.SetTools( list_of_one_shape(to_add2))
    fuse_op.Build()
    return fuse_op.Shape()

def show_changed_faces(inob1,inob2,outob):
    #inob1, inob2 and outob are OCC objects
    #goal is to output faces in outob that
    #are NOT in face set(inob1,inob2) [case1]
    #are NOT in face set(inob1) [case2]
    i1_f = cq.Shape.cast(inob1).Faces()
    i2_f = cq.Shape.cast(inob2).Faces()
    o_f = cq.Shape.cast(outob).Faces()
    def HashList(m_f):
        f_hash = []
        for m in m_f:
            f_hash.append(m.wrapped.HashCode(HASH_UPPER_BOUND))
        return f_hash

    def set_comp_brandnew(a,b,c):
        a1 = a+b #put two parent objects together
        bnewf = []
        for idx,m in enumerate(c):
            if m not in a1: #find new faces
                print(True,m,idx)
                bnewf.append(o_f[idx]) #face object
        return bnewf
    result = set_comp_brandnew(HashList(i1_f),HashList(i2_f),HashList(o_f))
    show_object(cq.Workplane().add(result).translate((0,-65,0)),name="brandnewfaces",options={"alpha":0.30, "color": rnco()})
    
    def set_comp_notfromOB1(a,c):
        notob1f = []
        for idx,m in enumerate(c):
            if m not in a: #find new faces
                print(True,m,idx)
                notob1f.append(o_f[idx]) #face object
        return notob1f
    
    result2 = set_comp_notfromOB1(HashList(i1_f),HashList(o_f))
    show_object(cq.Workplane().add(result2).translate((0,65,0)),name="notfromOB1",options={"alpha":0.30, "color": rnco()})
    
    def set_comp_notfromOB2(b,c):
        notob2f = []
        for idx,m in enumerate(c):
            if m not in a: #find new faces
                print(True,m,idx)
                notob2f.append(o_f[idx]) #face object
        return notob2f
    
    result3 = set_comp_notfromOB1(HashList(i2_f),HashList(o_f))
    show_object(cq.Workplane().add(result3).translate((0,65*2,0)),name="notfromOB2",options={"alpha":0.30, "color": rnco()})
    
occ_layer1 = layer1.val().wrapped
occ_layer2 = layer2.val().wrapped
occ_fuse_result = occ_native_fuse(occ_layer1,occ_layer2)

show_object(occ_fuse_result,options={"color":(55,0,55)})
show_changed_faces(occ_layer1,occ_layer2,occ_fuse_result)

#show_object(layer1.translate((0,65,0)),options={"color":rnco()})
#show_object(layer2.translate((0,65*2,0)), options={"color":rnco()})

dump_occ_obj(occ_fuse_result, name="fuse result")
dump_occ_obj(occ_layer1, name="layer1")
dump_occ_obj(occ_layer2, name="layer2")