Jam/cross.py

201 lines
6.5 KiB
Python
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2021-09-28 19:23:06 +00:00
import math
from kivy.graphics import Color,Line,Rectangle
from kivy.uix.widget import Widget
from point import Point
class Cross():
# size of central square
size=50
def __init__(self,x,y,**kwargs):
self.pos=Point(x,y)
self.color=kwargs.get("color",(0,0,1))
self.selected=False
# set position
def setpos(self,x,y):
self.pos.x=x
self.pos.y=y
def draw(self):
# fill
#if not self.selected:
# Color(*(self.color))
#else:
# Color(1,0,0)
Color(*(self.color))
Rectangle(pos=(self.pos.x-self.size*1.5,self.pos.y-self.size*0.5),size=(3*self.size,self.size))
Rectangle(pos=(self.pos.x-self.size*0.5,self.pos.y-self.size*1.5),size=(self.size,3*self.size))
# stroke
Color(1,1,1)
Line(points=(
*(self.pos.x-self.size*0.5,self.pos.y-self.size*0.5),
*(self.pos.x-self.size*0.5,self.pos.y-self.size*1.5),
*(self.pos.x+self.size*0.5,self.pos.y-self.size*1.5),
*(self.pos.x+self.size*0.5,self.pos.y-self.size*0.5),
*(self.pos.x+self.size*1.5,self.pos.y-self.size*0.5),
*(self.pos.x+self.size*1.5,self.pos.y+self.size*0.5),
*(self.pos.x+self.size*0.5,self.pos.y+self.size*0.5),
*(self.pos.x+self.size*0.5,self.pos.y+self.size*1.5),
*(self.pos.x-self.size*0.5,self.pos.y+self.size*1.5),
*(self.pos.x-self.size*0.5,self.pos.y+self.size*0.5),
*(self.pos.x-self.size*1.5,self.pos.y+self.size*0.5),
*(self.pos.x-self.size*1.5,self.pos.y-self.size*0.5),
*(self.pos.x-self.size*0.5,self.pos.y-self.size*0.5),
))
# check whether a cross at pos interacts with cross
def check_interaction(self,pos):
return ((pos-self.pos)/self.size).int()**2>=5
# find position along a line that comes in contact with the line going through pos in direction v
def move_on_line_to_stick(self,pos,v):
# relative to cross
return self.move_on_line_to_stick_relative((pos-self.pos)/self.size,v/self.size)*self.size+self.pos
def move_on_line_to_stick_relative(self,x,v):
# if x is in the right quadrant
if abs(x.y)<=x.x:
# find all stuck positions on lines
stuck=[]
# check intersections with vertical lines
if v.x!=0:
for i in range(1,4):
# candidate
y=Point(i,x.y+(i-x.x)*v.y/v.x)
# check that it is in the right range
if abs(y.y)<=4-i and abs(y.y)>=3-i:
stuck.append(y)
# check intersections with horizontal lines
if v.y!=0:
for i in [-3,-2,-1,1,2,3]:
# candidate
y=Point(x.x+(i-x.y)*v.x/v.y,i)
# check that it is in the right range
if y.x<=4-abs(i) and y.x>=3-abs(i):
stuck.append(y)
return x.closest(stuck)
# reflect other quadrants to the right one
# top quadrant
elif abs(x.x)<=x.y:
closest=self.move_on_line_to_stick_relative(Point(x.y,x.x),Point(v.y,v.x))
return Point(closest.y,closest.x)
# bottom quadrant
elif abs(x.x)<=-x.y:
closest=self.move_on_line_to_stick_relative(Point(-x.y,x.x),Point(-v.y,v.x))
return Point(closest.y,-closest.x)
# left quadrant
else:
closest=self.move_on_line_to_stick_relative(Point(-x.x,x.y),Point(-v.x,v.y))
return Point(-closest.x,closest.y)
# L_infinity distance rescalled by 3 in the x direction
def cross_distx(x,y):
return max(abs(x.x-y.x)/3,abs(x.y-y.y))
# L_infinity distance rescalled by 3 in the y direction
def cross_disty(x,y):
return max(abs(x.x-y.x),abs(x.y-y.y)/3)
# polar description of touching cross
def cross_polar(t):
# by symmetry, put angle in interval (-pi/4,pi/4), and take absolute value
tt=abs((t+math.pi/4)%(math.pi/2)-math.pi/4)
if tt<math.atan(1/3):
return 3/math.cos(tt)
elif tt<math.atan(1/2):
return 1/math.sin(tt)
else:
return 2/math.cos(tt)
# cross painter
class Cross_painter(Widget):
def __init__(self,**kwargs):
# list of crosses
self.crosses=[]
# selected cross
self.selected=None
# init Widget
super(Cross_painter,self).__init__(**kwargs)
# draw all crosses
def draw(self):
with self.canvas:
for cross in self.crosses:
cross.draw()
# respond to mouse down
def on_touch_down(self,touch):
# create new cross
if touch.button=="right":
if self.check_add(Point(touch.x,touch.y)):
new=Cross(touch.x,touch.y)
with self.canvas:
new.draw()
# add to list
self.crosses.append(new)
# select cross
if touch.button=="left":
# unselect
if self.selected!=None:
self.selected.selected=False
# find cross under touch
self.selected=self.find_cross(Point(touch.x,touch.y))
# select
if self.selected!=None:
self.selected.selected=True
# respond to drag
def on_touch_move(self,touch):
# only move on left click
if touch.button=="left" and self.selected!=None:
self.selected.pos=self.check_move(Point(touch.x,touch.y),self.selected)
# redraw
self.canvas.clear()
self.draw()
# find the cross at position pos
def find_cross(self,pos):
for cross in self.crosses:
if cross_distx(pos,cross.pos)<=cross.size/2 or cross_disty(pos,cross.pos)<=cross.size/2:
return cross
# none found
return None
# check that a cross can move to new position
def check_move(self,newpos,cross):
for other in self.crosses:
# do not compare a cross to itself
if other!=cross:
# move would make cross overlap with other
if other.check_interaction(newpos)==False:
# stick to the cross
return other.move_on_line_to_stick(cross.pos,newpos-cross.pos)
return newpos
# check that a cross can be added at position
def check_add(self,pos):
for cross in self.crosses:
if cross.check_interaction(pos)==False:
return False
return True