def zoom(self, x, y, s):
"""Zoom Canvas with center x,y and scale s."""
cx,cy = self._o2c(x,y)
self._xformz = la.translate(cx,cy)
self._xformz = la.mul(self._xformz,la.scale(s,s))
self._xformz = la.mul(self._xformz,la.translate(-cx,-cy))
sr = self["scrollregion"]
if sr:
srd = [self.tk.getdouble(x) for x in sr.split()]
c1 = la.vapply(self._xformz,(srd[0],srd[1],0,1))
c2 = la.vapply(self._xformz,(srd[2],srd[3],0,1))
self.config(scrollregion=(c1[0],c1[1],c2[0],c2[1]))
super().scale("fixed-to-window",cx,cy,1/s,1/s)
self.scale(tk.ALL,x,y,s,s)
self._xform = la.mul(self._xform,la.translate(x,y))
self._xform = la.mul(self._xform,la.scale(s,s))
self._xform = la.mul(self._xform,la.translate(-x,-y))
def apply_xform(self,cids,xform):
# 'arc', 'bitmap', 'image', 'line', 'oval', 'polygon', 'rectangle', 'text', or 'window'
for cid in cids:
t = self.type(cid)
if t == "polygon" or t == "line" or t == "text":
#print("poly style",t)
crds = [la.coords(x,y,0,1) for x,y in group_coords(self.coords(cid),2,0)]
#print("pre ",crds)
tcrds = [la.vapply(xform,c) for c in crds]
#print("post",tcrds)
tkcrds = [(c[0],c[1]) for c in tcrds]
self.coords(cid,tkcrds)
elif t == 'arc' or t == 'oval' or t == 'rectangle':
#print("arc style",t)
# transform only center
crds = self.coords(cid)
center = la.coords((crds[0]+crds[2])/2,(crds[1]+crds[3])/2,0,1)
w,h = crds[2]-crds[0],crds[3]-crds[1]
tc = la.vapply(xform,center)
#tw = vapply(xform,la.coords(w,0,0,0))
#th = vapply(xform,la.coords(0,h,0,0))
self.coords(cid,tc[0]-w/2,tc[1]-h/2,tc[0]+h/2,tc[1]+h/2)
else:
print("unknown type",t,cid)
def _c2o(self,cx,cy):
xformi = la.inverse(self._xform)
o = la.vapply(xformi,(cx,cy,0,1))
return o[0],o[1]
def _o2cv(self,ox,oy):
c = la.vapply(self._xform,la.point((ox,oy,0,0)))
return c[0],c[1]
def transform_vector(v, xform):
tv = la.vapply(xform, la.coords(v[0], v[1], 0, 0))
return la.coords(tv[0], tv[1])
def transform_point(p, xform):
tp = la.vapply(xform, la.coords(p[0], p[1], 0, 1))
return la.coords(tp[0], tp[1])
def transform_bezier_circle(hs, xform):
for i, h in enumerate(hs):
th = la.vapply(xform, la.coords(h[0], h[1], 0, h[2]))
hs[i] = la.coords(th[0], th[1], th[3])
return hs