Content # By Dan Hagon (@axiomsofchoice) # 05/06/2022 at a rainy EMFCamp # MIT License from tidal import * from app import TextApp from st7789_passthrough import tidal_display import st7789 import accelerometer from math import sin, cos, pi, sqrt, atan2 from random import uniform, randrange class Particle(): def __init__(self, disp_w, disp_h, cur_acc, max_speed=8., lifetime=10): self.position = (int(uniform(0., disp_w)), int(uniform(0., disp_h))) # Speed in pixels per tick (where tick is typically 100ms) speed = uniform(.75 * max_speed, max_speed) # Make sure the generated direction is within a sector of the circle norm = sqrt(cur_acc[0] * cur_acc[0] + cur_acc[1] * cur_acc[1]) cur_dir = (cur_acc[0] / norm, cur_acc[1] / norm) rad_dir = uniform(atan2(cur_dir[0], cur_dir[1]) - (0.1 * pi), atan2(cur_dir[0], cur_dir[1]) + 0.1 * pi) self.velocity = (speed * sin(rad_dir), speed * cos(rad_dir)) self.lifetime = randrange(lifetime // 2, lifetime) self.life_line = [] def update_pos(self, accel): self.position = (self.position[0] + self.velocity[0], self.position[1] + self.velocity[1]) self.velocity = (self.velocity[0] + accel[0], self.velocity[1] + accel[1]) self.lifetime -= 1 self.life_line.append(self.position) def draw(self): if len(self.life_line) > 1: for i in range(len(self.life_line)-1): tidal_display.line(int(self.life_line[i][0]), int(self.life_line[i][1]), int(self.life_line[i+1][0]), int(( self.life_line[i+1][1])), st7789.BLUE) tidal_display.line(int(self.pos[0]), int(self.pos[1]), int(self.pos[0] + self.vel[0]), int((self.pos[1] + self.vel[1])), st7789.WHITE) @property def pos(self): return self.position @property def vel(self): return self.velocity @property def is_live(self): return self.lifetime > 0 class ParticlesApp(TextApp): BG = BLACK FG = WHITE def seed_particles(self, w, h, curr_acc, max_particles=18): if self.particle_state is None: self.particle_state = [] num_parts = len(self.particle_state) self.particle_state.extend([Particle(w, h, curr_acc) for _ in range(max_particles - num_parts)]) def on_activate(self): super().on_activate() w = tidal_display.width() h = tidal_display.height() self.particle_state = [] #self.seed_particles(w, h) accelerometer.init() def animation_tick(): # Get acceleromter value accel_vals = accelerometer.get_xyz()[:2] # Flip one of the directions accel_vals = (accel_vals[0], -accel_vals[1]) # Update particle state for p in self.particle_state: p.update_pos(accel_vals) # Remove the dead particles self.particle_state = [p for p in self.particle_state if p.is_live] # If necessary add new particles self.seed_particles(w, h, accel_vals) # Redraw the screen self.window.cls() # Coords #self.window.println("(%f,\n%f)" % accel_vals) # Accelerometer # tidal_display.line(int(0.5 * w), # int(0.5 * h), # int((0.5 + (0.5 * accel_vals[0])) * w), # int((0.5 + (0.5 * accel_vals[1])) * h), # st7789.WHITE) # Draw particles for p in self.particle_state: p.draw() self.timer = self.periodic(100, animation_tick) def on_deactivate(self): super().on_deactivate() self.timer.cancel() main = ParticlesApp