Hi all,

I wrote script to Fix Concave Polygons, I hope it is very useful to fixing concave poly.

Thanks,

Maruthi.B

#Thank you for using my Script
#Developed by Maruthi.B
#Mail:maruthikrishnan@yahoo.com

#description:
#.Select concave polygon to run 
#.It will make proper polygon without any concave
#.It will work on creator 4.2 and later 

db = mgGetCurrentDb()

class indentcl:
    pass
    
cl = indentcl
cl.listPoly=[]

def listSelectedPolygon():
    listPoly = mgGetSelectList(db)
    mgDeselectAll(db)
    cl.listPoly=[]
    if listPoly:
        rec,x = mgGetNextRecInList (listPoly)
        while rec:
            cl.listPoly.append(rec)
            rec,x = mgGetNextRecInList (listPoly)
    else:
        mgSendMessage( MMSG_STATUS,"None of the polygon is selected")

def polyMerge(p1,p2,vtx1,vtx2):
    dupchild = []
    parent = mgGetParent(p1)
    rec = mgDuplicate(p1)
    mgAttach(parent,rec)
    localcount =1
    child = mgGetChild(p2)
    while child:
        dupchild.insert((len(dupchild)),mgDuplicate(child))
        localcount = localcount+1
        child =mgGetNext(child)
    
    localcount =1
    child = mgGetChild(rec)
    indexcheck =0
    indexcheck1 =0
    
    childCount = mgCountChild(p1)    
    
    if childCount in vtx1 and 1 in vtx1:
        indexcheck = childCount
        indexcheck1 = vtx2[1]
    else:
        indexcheck =vtx1[0]
        indexcheck1 =vtx2[0]
        
    for getvtx in range(len(dupchild)):
        if getvtx > indexcheck1-2:
            break
        else:
            getpop = dupchild.pop(0)
            dupchild.insert(len(dupchild),getpop)
            
    dupchild.pop(0)
    dupchild.pop(len(dupchild)-1)
    localcount=1
    count2=1
    child = mgGetChild(rec)    
    while child:
        if localcount == indexcheck:
            for dupch in range(len(dupchild)):
                if dupch ==0:
                    mgInsert(child,dupchild[dupch])
                else:
                    mgInsert(dupchild[dupch-1],dupchild[dupch])
        localcount = localcount+1
        child =mgGetNext(child)    
        
    mgDeselectAll(db)
    mgSelectOne(rec)
    mgExecute ("Combine Faces", None)

    if mgIsPolyConcave(rec) ==1:
        mgDetach(rec)
        mgDelete(rec)
        return 0
    else:
        mgDetach(p1)
        mgDelete(p1)
        mgDetach(p2)
        mgDelete(p2)
        return 1        
        

def polyCheck(p1,p2):
    p1list =[]
    p2list =[]
    p2Vtx =[]
    p1Vtx =[]

    if mgCountChild(p1) > 2 and mgCountChild(p2) > 2:
        p1child = mgGetChild(p1)
        while p1child:
            p1list.append(mgGetVtxCoord(p1child))
            p1child = mgGetNext(p1child)
    
        p2child = mgGetChild(p2)
        while p2child:
            p2list.append(mgGetVtxCoord(p2child))
            p2child = mgGetNext(p2child)        

        count =0
        for x in range(len(p1list)):
            for s in range(len(p2list)):
                if p1list[x] == p2list[s]:
                    count = count+1
                    p2Vtx.append(s+1)
                    p1Vtx.append(x+1)
        
        if count ==2:
             return polyMerge(p1,p2,p1Vtx,p2Vtx)
    return 0

def polyLoop(emptyGrp):
    result =1
    childFirst = mgGetChild(emptyGrp)
    child = mgGetChild(emptyGrp)
    while child:
        result = polyCheck(childFirst,mgGetNext(child))
        if result:    
            break
        child = mgGetNext(child)
    if not result:
        mgDetach(childFirst)
        mgAttach(cl.parent,childFirst)
        

def start(emptyGrp):
    if mgCountChild(emptyGrp) !=0:
        while mgCountChild(emptyGrp) > 1:
            polyLoop(emptyGrp)
        else:
            rec =mgGetChild(emptyGrp)
            mgDetach(rec)
            mgAttach(cl.parent,rec)

def TriangulateOne (polygon,grp):
    vertexList = mgGetTriangleList (polygon)
    numVertex = mgGetRecListCount (vertexList)
    if (numVertex > 3):
        numTriangles = numVertex / 3;
        for j in range (1, numTriangles+1):
            vtx1,matrix = mgGetNextRecInList (vertexList)
            vtx2,matrix = mgGetNextRecInList (vertexList)
            vtx3,matrix = mgGetNextRecInList (vertexList)
            newPoly = mgDuplicateEx (polygon, MDUP_NODEONLY)
            mgAttach(grp,newPoly)
            newVtx1 = mgDuplicate (vtx1)
            newVtx2 = mgDuplicate (vtx2)
            newVtx3 = mgDuplicate (vtx3)
            mgAttach (newPoly, newVtx3)
            mgAttach (newPoly, newVtx2)
            mgAttach (newPoly, newVtx1)
    
def polyConcaveRemove():
    listSelectedPolygon()
    emptyGrp = mgNewRec(fltGroup)
    if cl.listPoly:
        for rec in cl.listPoly:
            mgDeselectAll(db)
            if mgIsPolyConcave(rec) ==1:
                cl.parent =mgGetParent(rec)
                mgDetach(rec)
                mgAttach(emptyGrp,rec)
                TriangulateOne(rec,emptyGrp)
                mgDelete(rec)
                start(emptyGrp)
    mgDelete(emptyGrp)
    mgDeselectAll(db)
                
polyConcaveRemove()                

Thanks for sharing this. I bet others will find this useful!