Glue Bonus

1. Detect collision with 'glue' bonus

function bonuses.bonus_collected( i, bonus, ball, platform )
   .....
   elseif bonuses.is_glue( bonus ) then
      platform.react_on_glue_bonus()
   end
   .....
end

function bonuses.is_glue( single_bonus )
   local col = single_bonus.bonustype % 10
   return ( col == 2 )
end

2. When glue bonus is caught, platform tile is changed and glued flag is raised.

function platform.react_on_glue_bonus()
   platform.glued = true
   if platform.size == "small" then
      platform.quad = love.graphics.newQuad(
         platform.small_tile_x_pos + platfrom.glued_x_pos_shift,
         platform.small_tile_y_pos,
         platform.small_tile_width,
         platform.small_tile_height,
         platform.tileset_width,
         platform.tileset_height )
   elseif platform.size == "norm" then
      platform.quad = love.graphics.newQuad(
         platform.norm_tile_x_pos + platfrom.glued_x_pos_shift,
         platform.norm_tile_y_pos,
         platform.norm_tile_width,
         platform.norm_tile_height,
         platform.tileset_width,
         platform.tileset_height )
   elseif platform.size == "large" then
      platform.quad = love.graphics.newQuad(
         platform.large_tile_x_pos + platfrom.glued_x_pos_shift,
         platform.large_tile_y_pos,
         platform.large_tile_width,
         platform.large_tile_height,
         platform.tileset_width,
         platform.tileset_height )
   end   
end

3. Ball-platform collision depends on the value of the glued flag.

local first_launch_speed = vector( -150, -300 )
ball.platform_launch_speed = first_launch_speed:clone()

function ball.platform_rebound( shift_ball, platform )
   ball.increase_collision_counter()
   ball.increase_speed_after_collision()
   if not platform.glued then
      ball.normal_rebound( shift_ball )
      ball.rotate_speed( shift_ball, platform )
   else
      ball.normal_rebound( shift_ball )
      ball.rotate_speed( shift_ball, platform )
      ball.platform_launch_speed = ball.speed:clone()
      ball.stuck_to_platform = true      
      ball.speed = vector( 0, 0 )
      local platform_center = vector(
         platform.position.x + platform.width / 2,
         platform.position.y + platform.height / 2 )
      local ball_center = ball.position:clone()
      ball.separation_from_platform_center =
         ball_center - platform_center
      print( ball.separation_from_platform_center )
   end
end

function ball.launch_from_platform()
   if ball.stuck_to_platform then
      ball.stuck_to_platform = false
      ball.speed = ball.platform_launch_speed:clone()
   end
end

5. The glued effect is removed if any other bonus is caught, the ball is lost, or the next level is reached. ...

function platform.remove_glued_effect()
   platform.glued = false
   if platform.size == "small" then
      platform.quad = love.graphics.newQuad(
         platform.small_tile_x_pos,
         platform.small_tile_y_pos,
         platform.small_tile_width,
         platform.small_tile_height,
         platform.tileset_width,
         platform.tileset_height )
   elseif platform.size == "norm" then
      platform.quad = love.graphics.newQuad(
         platform.norm_tile_x_pos,
         platform.norm_tile_y_pos,
         platform.norm_tile_width,
         platform.norm_tile_height,
         platform.tileset_width,
         platform.tileset_height )
   elseif platform.size == "large" then
      platform.quad = love.graphics.newQuad(
         platform.large_tile_x_pos,
         platform.large_tile_y_pos,
         platform.large_tile_width,
         platform.large_tile_height,
         platform.tileset_width,
         platform.tileset_height )
   end      
end