particle.py

import random
import colorsys

class SandParticle:
	def __init__(self):
		self.color = random_color((0.1, 0.12), (0.5, 0.7), (0.7, 0.9))

	def update(self, grid, row, column):
		if grid.is_cell_empty(row + 1, column):
			return row + 1, column
		else:
			offsets = [-1, 1]
			random.shuffle(offsets)
			for offset in offsets:
				new_column = column + offset
				if grid.is_cell_empty(row +1, new_column):
					return row + 1, new_column

		return row, column

class RockParticle:
	def __init__(self):
		self.color = random_color((0.0, 0.1), (0.1, 0.3), (0.3, 0.5))

def random_color(hue_range, saturation_range, value_range):
	hue = random.uniform(*hue_range)
	saturation = random.uniform(*saturation_range)
	value = random.uniform(*value_range)
	r, g, b = colorsys.hsv_to_rgb(hue, saturation, value)
	return int(r * 255), int(g * 255), int(b * 255)