From 2a59bfdb7dfdc76e8a5f25fa74971aae6627e643 Mon Sep 17 00:00:00 2001 From: Antonio Ospite Date: Tue, 23 Jan 2007 23:58:07 +0100 Subject: [PATCH] Add an HSR helper class Signed-off-by: Antonio Ospite --- vrm.py | 621 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 598 insertions(+), 23 deletions(-) diff --git a/vrm.py b/vrm.py index 26a14d7..b121765 100755 --- a/vrm.py +++ b/vrm.py @@ -58,9 +58,8 @@ __bpydoc__ = """\ # - Implement Edge Styles (silhouettes, contours, etc.) (partially done). # - Implement Shading Styles? (partially done, to make more flexible). # - Add Vector Writers other than SVG. +# - set the background color! # - Check memory use!! -# - Support Indexed palettes!! (Useful for ILDA FILES, for example, -# see http://www.linux-laser.org/download/autotrace/ilda-output.patch) # # --------------------------------------------------------------------- # @@ -102,7 +101,7 @@ class config: polygons['SHOW'] = True polygons['SHADING'] = 'FLAT' #polygons['HSR'] = 'PAINTER' # 'PAINTER' or 'NEWELL' - polygons['HSR'] = 'PAINTER' + polygons['HSR'] = 'NEWELL' # Hidden to the user for now polygons['EXPANSION_TRICK'] = True @@ -112,24 +111,58 @@ class config: edges['SHOW'] = False edges['SHOW_HIDDEN'] = False edges['STYLE'] = 'MESH' # or SILHOUETTE - edges['STYLE'] = 'SILHOUETTE' edges['WIDTH'] = 2 edges['COLOR'] = [0, 0, 0] output = dict() output['FORMAT'] = 'SVG' - output['FORMAT'] = 'SWF' - output['ANIMATION'] = True + output['ANIMATION'] = False output['JOIN_OBJECTS'] = True + #output['FORMAT'] = 'SWF' + #output['ANIMATION'] = True # Utility functions +print_debug = False + +def dumpfaces(flist, filename): + """Dump a single face to a file. + """ + if not print_debug: + return + + class tmpmesh: + pass + + m = tmpmesh() + m.faces = flist + + writerobj = SVGVectorWriter(filename) + + writerobj.open() + writerobj._printPolygons(m) + + writerobj.close() + +def debug(msg): + if print_debug: + sys.stderr.write(msg) + +def EQ(v1, v2): + return (abs(v1[0]-v2[0]) < EPS and + abs(v1[1]-v2[1]) < EPS ) +by_furthest_z = (lambda f1, f2: + cmp(max([v.co[2] for v in f1]), max([v.co[2] for v in f2])+EPS) + ) + def sign(x): if x < -EPS: + #if x < 0: return -1 elif x > EPS: + #elif x > 0: return 1 else: return 0 @@ -137,9 +170,538 @@ def sign(x): # --------------------------------------------------------------------- # +## HSR Utility class +# +# --------------------------------------------------------------------- + +EPS = 10e-5 +INF = 10e5 + +class HSR: + """A utility class for HSR processing. + """ + + def is_nonplanar_quad(face): + """Determine if a quad is non-planar. + + From: http://mathworld.wolfram.com/Coplanar.html + + Geometric objects lying in a common plane are said to be coplanar. + Three noncollinear points determine a plane and so are trivially coplanar. + Four points are coplanar iff the volume of the tetrahedron defined by them is + 0, + + | x_1 y_1 z_1 1 | + | x_2 y_2 z_2 1 | + | x_3 y_3 z_3 1 | + | x_4 y_4 z_4 1 | == 0 + + Coplanarity is equivalent to the statement that the pair of lines + determined by the four points are not skew, and can be equivalently stated + in vector form as (x_3-x_1).[(x_2-x_1)x(x_4-x_3)]==0. + + An arbitrary number of n points x_1, ..., x_n can be tested for + coplanarity by finding the point-plane distances of the points + x_4, ..., x_n from the plane determined by (x_1,x_2,x_3) + and checking if they are all zero. + If so, the points are all coplanar. + + We here check only for 4-point complanarity. + """ + n = len(face) + + # assert(n>4) + if n < 3 or n > 4: + print "ERROR a mesh in Blender can't have more than 4 vertices or less than 3" + raise AssertionError + + elif n == 3: + # three points must be complanar + return False + else: # n == 4 + x1 = Vector(face[0].co) + x2 = Vector(face[1].co) + x3 = Vector(face[2].co) + x4 = Vector(face[3].co) + + v = (x3-x1) * CrossVecs((x2-x1), (x4-x3)) + if v != 0: + return True + + return False + + is_nonplanar_quad = staticmethod(is_nonplanar_quad) + + def pointInPolygon(poly, v): + return False + + pointInPolygon = staticmethod(pointInPolygon) + + def edgeIntersection(s1, s2, do_perturbate=False): + + (x1, y1) = s1[0].co[0], s1[0].co[1] + (x2, y2) = s1[1].co[0], s1[1].co[1] + + (x3, y3) = s2[0].co[0], s2[0].co[1] + (x4, y4) = s2[1].co[0], s2[1].co[1] + + #z1 = s1[0].co[2] + #z2 = s1[1].co[2] + #z3 = s2[0].co[2] + #z4 = s2[1].co[2] + + + # calculate delta values (vector components) + dx1 = x2 - x1; + dx2 = x4 - x3; + dy1 = y2 - y1; + dy2 = y4 - y3; + + #dz1 = z2 - z1; + #dz2 = z4 - z3; + + C = dy2 * dx1 - dx2 * dy1 # /* cross product */ + if C == 0: #/* parallel */ + return None + + dx3 = x1 - x3 # /* combined origin offset vector */ + dy3 = y1 - y3 + + a1 = (dy3 * dx2 - dx3 * dy2) / C; + a2 = (dy3 * dx1 - dx3 * dy1) / C; + + # check for degeneracies + #print_debug("\n") + #print_debug(str(a1)+"\n") + #print_debug(str(a2)+"\n\n") + + if (a1 == 0 or a1 == 1 or a2 == 0 or a2 == 1): + # Intersection on boundaries, we consider the point external? + return None + + elif (a1>0.0 and a1<1.0 and a2>0.0 and a2<1.0): # /* lines cross */ + x = x1 + a1*dx1 + y = y1 + a1*dy1 + + #z = z1 + a1*dz1 + z = 0 + return (NMesh.Vert(x, y, z), a1, a2) + + else: + # lines have intersections but not those segments + return None + + edgeIntersection = staticmethod(edgeIntersection) + + def isVertInside(self, v): + winding_number = 0 + coincidence = False + + # Create point at infinity + point_at_infinity = NMesh.Vert(-INF, v.co[1], -INF) + + for i in range(len(self.v)): + s1 = (point_at_infinity, v) + s2 = (self.v[i-1], self.v[i]) + + if EQ(v.co, s2[0].co) or EQ(v.co, s2[1].co): + coincidence = True + + if HSR.edgeIntersection(s1, s2, do_perturbate=False): + winding_number += 1 + + # Check even or odd + if winding_number % 2 == 0 : + return False + else: + if coincidence: + return False + return True + + isVertInside = staticmethod(isVertInside) + + def projectionsOverlap(f1, f2): + """ If you have nonconvex, but still simple polygons, an acceptable method + is to iterate over all vertices and perform the Point-in-polygon test[1]. + The advantage of this method is that you can compute the exact + intersection point and collision normal that you will need to simulate + collision. When you have the point that lies inside the other polygon, you + just iterate over all edges of the second polygon again and look for edge + intersections. Note that this method detects collsion when it already + happens. This algorithm is fast enough to perform it hundreds of times per + sec. """ + + for i in range(len(f1.v)): + + + # If a point of f1 in inside f2, there is an overlap! + v1 = f1.v[i] + if HSR.isVertInside(f2, v1): + return True + + # If not the polygon can be ovelap as well, so we check for + # intersection between an edge of f1 and all the edges of f2 + + v0 = f1.v[i-1] + + for j in range(len(f2.v)): + v2 = f2.v[j-1] + v3 = f2.v[j] + + e1 = v0, v1 + e2 = v2, v3 + + intrs = HSR.edgeIntersection(e1, e2) + if intrs: + #print_debug(str(v0.co) + " " + str(v1.co) + " " + + # str(v2.co) + " " + str(v3.co) ) + #print_debug("\nIntersection\n") + + return True + + return False + + projectionsOverlap = staticmethod(projectionsOverlap) + + def midpoint(p1, p2): + """Return the midpoint of two vertices. + """ + m = MidpointVecs(Vector(p1), Vector(p2)) + mv = NMesh.Vert(m[0], m[1], m[2]) + + return mv + + midpoint = staticmethod(midpoint) + + def facesplit(P, Q, facelist, nmesh): + """Split P or Q according to the strategy illustrated in the Newell's + paper. + """ + + by_furthest_z = (lambda f1, f2: + cmp(max([v.co[2] for v in f1]), max([v.co[2] for v in f2])+EPS) + ) + + # Choose if split P on Q plane or vice-versa + + n = 0 + for Pi in P: + d = HSR.Distance(Vector(Pi), Q) + if d <= EPS: + n += 1 + pIntersectQ = (n != len(P)) + + n = 0 + for Qi in Q: + d = HSR.Distance(Vector(Qi), P) + if d >= -EPS: + n += 1 + qIntersectP = (n != len(Q)) + + newfaces = [] + + # 1. If parts of P lie in both half-spaces of Q + # then splice P in two with the plane of Q + if pIntersectQ: + #print "We split P" + f = P + plane = Q + + newfaces = HSR.splitOn(plane, f) + + # 2. Else if parts of Q lie in both half-space of P + # then splice Q in two with the plane of P + if qIntersectP and newfaces == None: + #print "We split Q" + f = Q + plane = P + + newfaces = HSR.splitOn(plane, f) + #print "After" + + # 3. Else slice P in half through the mid-point of + # the longest pair of opposite sides + if newfaces == None: + + print "We ignore P..." + facelist.remove(P) + return facelist + + #f = P + + #if len(P)==3: + # v1 = midpoint(f[0], f[1]) + # v2 = midpoint(f[1], f[2]) + #if len(P)==4: + # v1 = midpoint(f[0], f[1]) + # v2 = midpoint(f[2], f[3]) + #vec3 = (Vector(v2)+10*Vector(f.normal)) + # + #v3 = NMesh.Vert(vec3[0], vec3[1], vec3[2]) + + #plane = NMesh.Face([v1, v2, v3]) + # + #newfaces = splitOn(plane, f) + + + if newfaces == None: + print "Big FAT problem, we weren't able to split POLYGONS!" + raise AssertionError + + #print newfaces + if newfaces: + #for v in f: + # if v not in plane and v in nmesh.verts: + # nmesh.verts.remove(v) + for nf in newfaces: + + nf.mat = f.mat + nf.sel = f.sel + nf.col = [f.col[0]] * len(nf.v) + + nf.smooth = 0 + + for v in nf: + nmesh.verts.append(v) + # insert pieces in the list + facelist.append(nf) + + facelist.remove(f) + + # and resort the faces + facelist.sort(by_furthest_z) + facelist.sort(lambda f1, f2: cmp(f1.smooth, f2.smooth)) + facelist.reverse() + + #print [ f.smooth for f in facelist ] + + return facelist + + facesplit = staticmethod(facesplit) + + def isOnSegment(v1, v2, p, extremes_internal=False): + """Check if point p is in segment v1v2. + """ + + l1 = (v1-p).length + l2 = (v2-p).length + + # Should we consider extreme points as internal ? + # The test: + # if p == v1 or p == v2: + if l1 < EPS or l2 < EPS: + return extremes_internal + + l = (v1-v2).length + + # if the sum of l1 and l2 is circa l, then the point is on segment, + if abs(l - (l1+l2)) < EPS: + return True + else: + return False + + isOnSegment = staticmethod(isOnSegment) + + def Distance(point, face): + """ Calculate the distance between a point and a face. + + An alternative but more expensive method can be: + + ip = Intersect(Vector(face[0]), Vector(face[1]), Vector(face[2]), + Vector(face.no), Vector(point), 0) + + d = Vector(ip - point).length + + See: http://mathworld.wolfram.com/Point-PlaneDistance.html + """ + + p = Vector(point) + plNormal = Vector(face.no) + plVert0 = Vector(face.v[0]) + + d = (plVert0 * plNormal) - (p * plNormal) + + #d = plNormal * (plVert0 - p) + + #print "\nd: %.10f - sel: %d, %s\n" % (d, face.sel, str(point)) + + return d + + Distance = staticmethod(Distance) + + def makeFaces(vl): + # + # make one or two new faces based on a list of vertex-indices + # + newfaces = [] + + if len(vl) <= 4: + nf = NMesh.Face() + + for v in vl: + nf.v.append(v) + + newfaces.append(nf) + + else: + nf = NMesh.Face() + + nf.v.append(vl[0]) + nf.v.append(vl[1]) + nf.v.append(vl[2]) + nf.v.append(vl[3]) + newfaces.append(nf) + + nf = NMesh.Face() + nf.v.append(vl[3]) + nf.v.append(vl[4]) + nf.v.append(vl[0]) + newfaces.append(nf) + + return newfaces + + makeFaces = staticmethod(makeFaces) + + def splitOn(Q, P): + """Split P using the plane of Q. + Logic taken from the knife.py python script + """ + + # Check if P and Q are parallel + u = CrossVecs(Vector(Q.no),Vector(P.no)) + ax = abs(u[0]) + ay = abs(u[1]) + az = abs(u[2]) + + if (ax+ay+az) < EPS: + print "PARALLEL planes!!" + return + + + # The final aim is to find the intersection line between P + # and the plane of Q, and split P along this line + + nP = len(P.v) + + # Calculate point-plane Distance between vertices of P and plane Q + d = [] + for i in range(0, nP): + d.append(HSR.Distance(P.v[i], Q)) + + newVertList = [] + + posVertList = [] + negVertList = [] + for i in range(nP): + d0 = d[i-1] + V0 = P.v[i-1] + + d1 = d[i] + V1 = P.v[i] + + #print "d0:", d0, "d1:", d1 + + # if the vertex lies in the cutplane + if abs(d1) < EPS: + #print "d1 On cutplane" + posVertList.append(V1) + negVertList.append(V1) + else: + # if the previous vertex lies in cutplane + if abs(d0) < EPS: + #print "d0 on Cutplane" + if d1 > 0: + #print "d1 on positive Halfspace" + posVertList.append(V1) + else: + #print "d1 on negative Halfspace" + negVertList.append(V1) + else: + # if they are on the same side of the plane + if d1*d0 > 0: + #print "On the same half-space" + if d1 > 0: + #print "d1 on positive Halfspace" + posVertList.append(V1) + else: + #print "d1 on negative Halfspace" + negVertList.append(V1) + + # the vertices are not on the same side of the plane, so we have an intersection + else: + #print "Intersection" + + e = Vector(V0), Vector(V1) + tri = Vector(Q[0]), Vector(Q[1]), Vector(Q[2]) + + inters = Intersect(tri[0], tri[1], tri[2], e[1]-e[0], e[0], 0) + if inters == None: + print "Split Break" + break + + #print "Intersection", inters + + nv = NMesh.Vert(inters[0], inters[1], inters[2]) + newVertList.append(nv) + + posVertList.append(nv) + negVertList.append(nv) + + if d1 > 0: + posVertList.append(V1) + else: + negVertList.append(V1) + + + # uniq + posVertList = [ u for u in posVertList if u not in locals()['_[1]'] ] + negVertList = [ u for u in negVertList if u not in locals()['_[1]'] ] + + + # If vertex are all on the same half-space, return + #if len(posVertList) < 3: + # print "Problem, we created a face with less that 3 verteices??" + # posVertList = [] + #if len(negVertList) < 3: + # print "Problem, we created a face with less that 3 verteices??" + # negVertList = [] + + if len(posVertList) < 3 or len(negVertList) < 3: + print "RETURN NONE, SURE???" + return None + + + newfaces = HSR.addNewFaces(posVertList, negVertList) + + return newfaces + + splitOn = staticmethod(splitOn) + + def addNewFaces(posVertList, negVertList): + # Create new faces resulting from the split + outfaces = [] + if len(posVertList) or len(negVertList): + + #newfaces = [posVertList] + [negVertList] + newfaces = ( [[ NMesh.Vert(v[0], v[1], v[2]) for v in posVertList]] + + [[ NMesh.Vert(v[0], v[1], v[2]) for v in negVertList]] ) + + for nf in newfaces: + if nf and len(nf)>2: + outfaces += HSR.makeFaces(nf) + + return outfaces + + + addNewFaces = staticmethod(addNewFaces) + + +# --------------------------------------------------------------------- +# ## Mesh Utility class # # --------------------------------------------------------------------- + class MeshUtils: def buildEdgeFaceUsersCache(me): @@ -222,6 +784,7 @@ class MeshUtils: ## Shading Utility class # # --------------------------------------------------------------------- + class ShadingUtils: shademap = None @@ -791,10 +1354,11 @@ class SVGVectorWriter(VectorWriter): self.file.write("= -EPS: n += 1 qVerticesInFrontPlaneP = (n == len(Q)) @@ -1810,7 +2378,8 @@ class Renderer: # Test 5: Check if projections of polygons effectively overlap, # in previous tests we checked only bounding boxes. - if not projectionsOverlap(P, Q): + #if not projectionsOverlap(P, Q): + if not ( HSR.projectionsOverlap(P, Q) or HSR.projectionsOverlap(Q, P)): debug("\nTest 5\n") debug("Projections do not overlap!\n") continue @@ -1824,7 +2393,7 @@ class Renderer: debug("Possibly a cycle detected!\n") debug("Split here!!\n") - facelist = facesplit(P, Q, facelist, nmesh) + facelist = HSR.facesplit(P, Q, facelist, nmesh) split_done = 1 break @@ -1834,7 +2403,7 @@ class Renderer: # Test 3bis: Q vertices are all behind the plane of P n = 0 for Qi in Q: - d = pSign * Distance(Vector(Qi), P) + d = pSign * HSR.Distance(Vector(Qi), P) if d <= EPS: n += 1 qVerticesBehindPlaneP = (n == len(Q)) @@ -1847,7 +2416,7 @@ class Renderer: # Test 4bis: P vertices in front of the plane of Q n = 0 for Pi in P: - d = qSign * Distance(Vector(Pi), Q) + d = qSign * HSR.Distance(Vector(Pi), Q) if d >= -EPS: n += 1 pVerticesInFrontPlaneQ = (n == len(P)) @@ -1864,7 +2433,7 @@ class Renderer: debug("Test 3bis or 4bis failed\n") debug("Split here!!2\n") - facelist = facesplit(P, Q, facelist, nmesh) + facelist = HSR.facesplit(P, Q, facelist, nmesh) split_done = 1 break @@ -1874,14 +2443,19 @@ class Renderer: face_marked = 1 debug("Q marked!\n") break - + # Write P! if split_done == 0 and face_marked == 0: facelist.remove(P) maplist.append(P) + dumpfaces(maplist, "dump"+str(len(maplist)).zfill(4)+".svg") progress.update() + if len(facelist) == 870: + dumpfaces([P, Q], "loopdebug.svg") + + #if facelist == None: # maplist = [P, Q] # print [v.co for v in P] @@ -1892,8 +2466,8 @@ class Renderer: nmesh.faces = maplist - for f in nmesh.faces: - f.sel = 1 + #for f in nmesh.faces: + # f.sel = 1 nmesh.update() @@ -1943,7 +2517,6 @@ class Renderer: if edgestyleSelect(e, mesh): e.sel = 1 """ - # --------------------------------------------------------------------- @@ -2202,6 +2775,8 @@ def vectorize(filename): if editmode: Window.EditMode(1) + + # Here the main if __name__ == "__main__": -- 2.1.4