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| def TriSign(a,b,c): | |
| return (a.x - c.x) * (b.y- c.y) - (a.y-c.y) * (b.x-c.x) | |
| class pLine: | |
| def __init__(self, x1,y1,x2,y2): | |
| self.a = PVector(x1,y1) | |
| self.b = PVector(x2,y2) | |
| def pnorm(self): | |
| ret = (self.a - self.b) | |
| ret.normalize() | |
| ret.rotate(3.141/2) | |
| return ret | |
| def pdraw(self,dest = None): | |
| if dest: | |
| dest.line(self.a.x, self.a.y, self.b.x, self.b.y) | |
| else: | |
| line(self.a.x, self.a.y, self.b.x, self.b.y) | |
| def intersect(self, other): | |
| (a,b,c,d) = (self.a, self.b, other.a, other.b) | |
| a1 = TriSign(a,b,d) | |
| a2 = TriSign(a,b,c) | |
| if a1*a2 < 0.0: | |
| a3 = TriSign(c,d,a) | |
| a4 = a3+a2-a1 | |
| if a3*a4 < 0.0: | |
| t = a3 / (a3 - a4) | |
| p = a + t * (b-a) | |
| return (t,p) | |
| return False | |
| def __str__(self): | |
| return str(self.a) + " " + str(self.b) | |
| class hatch: | |
| # <---0---> | |
| def __init__(self, cx,cy, rx,ry): | |
| self.north = pLine(cx,cy,rx,ry) | |
| (dx, dy) = (rx-cx, ry-cy) | |
| self.south = pLine(cx,cy, cx - dx, cy-dy); | |
| def pdraw(self, dest = None): | |
| self.north.pdraw(dest) | |
| self.south.pdraw(dest) | |
| def clipHatch(self, other): | |
| intersect = self.north.intersect(other) | |
| tn,ts = (1,1) | |
| if intersect: | |
| tn,p = intersect | |
| self.north.b = p | |
| intersect = self.south.intersect(other) | |
| if intersect: | |
| ts,p = intersect | |
| self.south.b = p | |
| return (tn,ts) | |
| class patch: | |
| def __init__(self, c, e, hatches): | |
| self.axis = hatch(c.x, c.y, e.x,e.y) | |
| self.tn = 1 | |
| self.ts = 1 | |
| shortaxis = (c-e) | |
| nn = (c - e) | |
| nn.rotate(3.141/2) | |
| hatchDist = nn.mag() | |
| self.hatches = [] | |
| for i in range(-hatches,1+hatches): | |
| nc = PVector.lerp(c,e, ((1.*i)/hatches)) | |
| m = hatch(nc.x , nc.y, nc.x + nn.x, nc.y + nn.y) | |
| self.hatches.append(((1.*i)/hatches, m)) | |
| def pdraw(self,dest= None ): | |
| for h in self.hatches: | |
| h[1].pdraw(dest) | |
| def clipPatch(self, other): | |
| #todo keep this tn,ts ongoing? | |
| (tn, ts) = self.axis.clipHatch(other) | |
| self.tn = min(self.tn, tn) | |
| self.ts = min(self.ts, ts) | |
| self.hatches = [h for h in self.hatches if h[0] < tn and h[0] > -ts] | |
| for i in range(len(self.hatches)): | |
| self.hatches[i][1].clipHatch(other) | |
| def finalize(self, zones): | |
| for h in self.hatches: | |
| loca, locb, locc = hash(h[1].north.a), hash(h[1].north.b), hash(h[1].south.b) | |
| zones.setdefault(loca,[]).append(h[1].north) | |
| zones.setdefault(locb,[]).append(h[1].north) | |
| zones.setdefault(locb,[]).append(h[1].south) | |
| zones.setdefault(locc,[]).append(h[1].south) | |
| # TODO: implement distance map | |
| buckets = 600 | |
| zone = {} | |
| def hash(p): | |
| #return (1,1) | |
| return (int(p.x/buckets), int(p.y/buckets)) | |
| def neighbors(p): | |
| if (type(p) is PVector): | |
| p = hash(p) | |
| hood = [ (p[0] + x, p[1] + y) for x in range(-1,2) for y in range(-1, 2)] | |
| flatten = lambda l: [item for sublist in l for item in sublist] | |
| return flatten([zone.get(n,[]) for n in hood]) | |
| ### end todo | |
| pg = []; | |
| def setup(): | |
| size(600, 600) | |
| global pg | |
| pg = createGraphics(600,600) | |
| (top,left,right,bottom) = (100, 100, 500, 500) | |
| sz = 70 | |
| border = [] | |
| border.append(pLine(top, left, top, right)) | |
| border.append(pLine(top, left, bottom, left)) | |
| border.append(pLine(top, right, bottom, right)) | |
| border.append(pLine(bottom, left, bottom, right)) | |
| c = PVector(random(left,right),random(top,bottom)) | |
| toggle = False | |
| def draw(): | |
| global c | |
| global toggle | |
| global zone | |
| global sz | |
| stroke(0) | |
| if(mousePressed and sz > 0): | |
| if not toggle: | |
| #toggle = True | |
| while True: | |
| mouse = c + PVector(random(-sz,sz),random(-sz,sz)) | |
| if mouse.x > 0 and mouse.x < 600 and mouse.y > 0 and mouse.y < 600: | |
| break; | |
| p = patch(c, mouse, 4) | |
| for b in border: | |
| p.clipPatch(b) | |
| b.pdraw(pg) | |
| for n in neighbors(c): | |
| p.clipPatch(n) | |
| p.finalize(zone) | |
| p.pdraw() | |
| c = mouse | |
| else: | |
| toggle = False |
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