#
# Animated MCMC for Hardcore model on a grid
# Bryan Clair, June 2012
#
from cs1graphics import *
from HardcoreGrid import HardcoreGrid

class HCAnimated:
    """A graphic display of the MCMC for the Hardcore model"""
    def __init__(self,state):
        """Create display and all (invisible) particles"""
        self._state = state
        self._sizex,self._sizey = state.size()
        self._spacing = 20  # between lines
        radius = self._spacing * .7  # sqrt(2)/2, basically

        self._c = Canvas((self._sizex-1)*self._spacing+2*radius,
                         (self._sizey-1)*self._spacing+2*radius)

        # Draw the grids
        s = radius
        for x in range(self._sizex):
            self._c.add(Path(Point(s,radius),Point(s,self._c.getHeight()-radius)))
            s += self._spacing
        s = radius
        for y in range(self._sizey):
            self._c.add(Path(Point(radius,s),Point(self._c.getWidth()-radius,s)))
            s += self._spacing

        # Create the particles
        self._particles = list()
        for x in range(self._sizex):
            col = list()
            for y in range(self._sizey):
                p = Circle(radius,
                           Point(radius+x*self._spacing,radius+y*self._spacing))
                p.setFillColor('red' if (x+y)%2 else 'blue')
                col.append(p)
                if self._state.occupied(x,y):
                    self._c.add(p)
            self._particles.append(col)

    def update(self,x,y):
        """Update the graphical display, given that (x,y) just changed"""
        if self._state.occupied(x,y):
            self._c.add(self._particles[x][y])
        else:
            self._c.remove(self._particles[x][y])

if __name__ == '__main__':
    state = HardcoreGrid(20,20,1)
    pic = HCAnimated(state)
    steps = 0
    while True:
        spot = state.oneStepGlauber()
        steps += 1
        if steps % 1000 == 0:
            print 'density: %.2f\tpolarity: %.2f\tsteps: %d' %\
                  (state.density(),state.polarity(),steps)
        if spot:
            (x,y) = spot
            pic.update(x,y)