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#!/usr/bin/python
import py2geom
import toyframework
import random,gtk
from py2geom_glue import *
def cairo_pw(cr, p):
for i in range(p.size()):
a,b = p.cuts[i], p.cuts[i+1]
bez = sbasis_to_bezier(p[i], 0)
cr.move_to(a, bez[0])
cr.curve_to(lerp(a, b, 1./3), bez[1],
lerp(a,b, 2./3), bez[2],
b, bez[3])
def cairo_horiz(cr, y, ps):
for p in ps:
cr.move_to(p, y);
cr.rel_line_to(0, 10)
def cairo_vert(cr, x, ps):
for p in ps:
cr.move_to(x, p)
cr.rel_line_to(10, 0)
def l2s(l):
sb = py2geom.SBasis(l)
return sb
def constant(l):
pws = py2geom.PiecewiseSBasis()
pws.push_cut(0)
pws.push_seg(l2s(py2geom.Linear(l,l)) )
pws.push_cut(1000)
return pws
X = l2s(py2geom.Linear(0, 1))
OmX = l2s(py2geom.Linear(1, 0))
def bezier_to_sbasis(handles, order):
if(order == 0):
return l2s(py2geom.Linear(handles[0]))
elif(order == 1):
return l2s(py2geom.Linear(handles[0], handles[1]))
else:
return (py2geom.multiply(OmX, bezier_to_sbasis(handles[:-1], order-1)) +
py2geom.multiply(X, bezier_to_sbasis(handles[1:], order-1)))
def bez_to_sbasis(handles, order):
return bezier_to_sbasis([h[1] for h in handles], order)
class PWSBHandle(toyframework.Handle):
def __init__(self, cs, segs):
self.handles_per_curve = cs*segs
self.curve_size = cs
self.segs = segs
self.pts = []
def append(self, x, y):
self.pts.append(py2geom.Point(x,y))
def value(self, y_0=0):
pws = py2geom.PiecewiseSBasis()
for i in range(0, self.handles_per_curve, self.curve_size):
pws.push_cut(self.pts[i][0]);
for j in range(i, i + self.curve_size):
self.pts[j] = py2geom.Point(self.pts[j][0], self.pts[j][1] - y_0)
hnd = self.pts[i:i+self.curve_size]
pws.push_seg( bez_to_sbasis(hnd, self.curve_size-1));
for j in range(i, i + self.curve_size):
self.pts[j] = py2geom.Point(self.pts[j][0], self.pts[j][1] + y_0);
pws.push_cut(self.pts[self.handles_per_curve - 1][0]);
assert(pws.invariants());
return pws
def draw(self, cr, annotes):
for p in self.pts:
toyframework.draw_circ(cr, p)
def hit(self, mouse):
for i,p in enumerate(self.pts):
if(py2geom.distance(py2geom.Point(*mouse), p) < 5):
return i
return None
def move_to(self, hit, om, m):
om = py2geom.Point(*om)
m = py2geom.Point(*m)
if hit != None:
i,hand = hit
self.pts[hand] = m
for i in range(self.curve_size, self.handles_per_curve, self.curve_size):
self.pts[i-1] = py2geom.Point(self.pts[i][0],self.pts[i-1][1])
for i in range(0, self.handles_per_curve, self.curve_size):
for j in range(1, (self.curve_size-1)):
t = float(j)/(self.curve_size-1)
x = lerp(self.pts[i][0], self.pts[i+self.curve_size-1][0],t)
self.pts[i+j] = py2geom.Point(x, self.pts[i+j][1])
class PwToy(toyframework.Toy):
def __init__(self):
toyframework.Toy.__init__(self)
self.segs = 2
self.handles_per_curve = 4 * self.segs
self.curves = 2
self.pwsbh = []
self.interval_test = []
for a in range(self.curves):
self.pwsbh.append(PWSBHandle(4, self.curves))
self.handles.append(self.pwsbh[a])
for i in range(self.handles_per_curve):
t = 150 + 300*i/(4*self.segs)
self.pwsbh[a].append(t, random.uniform(0,1) * 150 + 150 - 50 * a)
self.interval_test.append(toyframework.PointHandle(150, 400))
self.interval_test.append(toyframework.PointHandle(300, 400))
self.handles.append(self.interval_test[0])
self.handles.append(self.interval_test[1])
self.func = "pws[0] + pws[1]"
def gtk_ready(self):
import gtk
self.sb_entry = gtk.Entry()
self.sb_entry.connect("changed", self.sb_changed)
toyframework.get_vbox().add(self.sb_entry)
toyframework.get_vbox().show_all()
self.sb_entry.set_text(self.func)
def sb_changed(self, sb):
self.func = sb.get_text()
self.redraw()
def draw(self, cr, pos, save):
cr.set_source_rgba (0., 0., 0., 1)
cr.set_line_width (1)
pws = [self.pwsbh[i].value() for i in range(self.curves)]
for p in pws:
cairo_pw(cr, p)
cr.stroke()
d = locals().copy()
for i in dir(py2geom):
d[i] = py2geom.__dict__[i]
d['l2s'] = l2s
d['constant'] = constant
pw_out = eval(self.func, d)
bs = py2geom.bounds_local(pw_out, py2geom.OptInterval(
py2geom.Interval(self.interval_test[0].pos[0],
self.interval_test[1].pos[0])));
if not bs.isEmpty():
bs = bs.toInterval()
for ph in self.interval_test:
ph.pos= py2geom.Point(ph.pos[0], bs.middle())
cr.save()
cr.set_source_rgba (.0, 0.25, 0.5, 1.)
cr.rectangle(self.interval_test[0].pos[0], bs.min(),
self.interval_test[1].pos[0]-self.interval_test[0].pos[0], bs.extent())
cr.stroke()
bs = py2geom.bounds_exact(pw_out);
cr.set_source_rgba (0.25, 0.25, .5, 1.);
if not bs.isEmpty():
bs = bs.toInterval()
cairo_horiz(cr, bs.middle(), pw_out.cuts);
cr.stroke()
cr.restore()
cr.set_source_rgba (0., 0., .5, 1.);
cairo_pw(cr, pw_out)
cr.stroke()
self.notify = str(bs)
toyframework.Toy.draw(self, cr, pos, save)
t = PwToy()
import sys
toyframework.init(sys.argv, t, 500, 500)
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