スイカゲーム風サンプル

ball_merge_game.rb

require 'rubysketch'
using RubySketch

STEP       = 20
SIZE_RANGE = 20..100

def nextSize()
  SIZE_RANGE.step(STEP).to_a.sample
end

def createBall(x, y, size)
  ball = createSprite x, y, shape: Circle.new(0, 0, size)
  ball.restitution = 0.5
  ball.friction    = 1

  ball.draw do |&draw|
    draw.call
    push do
      fill 0
      textSize size / 2
      textAlign CENTER, CENTER
      text size, 0, 0, size, size
    end
  end

  ball.contact do |other|
    if other.width == size && $balls.include?(other)
      remove ball, other
      pos = (ball.pos + other.pos) / 2
      createBall(pos.x, pos.y, size + STEP).dynamic = true
    end
  end

  $balls << ball
  ball
end

def remove(*balls)
  balls.each do |ball|
    removeSprite ball
    $balls.delete ball
  end
end

noStroke
gravity 0, 1000

walls = [
  createSprite(0, height - 10, width, 10),
  createSprite(0,          0, 10, height),
  createSprite(width - 10, 0, 10, height)
]
walls.each {_1.friction = 1}

$balls    = []
$nextBall = createBall 0, 0, nextSize

draw do
  $nextBall&.center = [mouseX, 20]
  background 100
  sprite *$balls, *walls
end

mousePressed do
  $nextBall&.dynamic = true
  $nextBall = nil
  setTimeout 1 do
    $nextBall = createBall 0, 0, nextSize
  end
end