reward_by_max_waypoint

gistfile1.txt

prev_max_distance_reward = 0
--only get reward for going over prior max
--calculates reward based on where you are in terms of waypoints and progress to next waypoint
function reward_by_max_waypoint()

    frame_count = frame_count + 1
    local level_done = calc_progress(data)

    --local reward = reward_by_ring(data)
    local reward = 0
    calc_waypoint(data) --increments waypoint

    if waypoint_reward_scale == nil then
	    local total_distance = get_total_distance(prev_x,prev_y)
	    waypoint_reward_scale = 9000.0/total_distance
	    prev_same_screen_y = data.screen_y
	    prev_anchor_y = nil
    end

    --deaths aren't registed right away but sonic will move a lot on the y axis
	  --this is a rough check for that
    if (data.x == prev_x) and (data.screen_y == prev_screen_y) then
	    prev_same_x = prev_same_x + 1
	    prev_same_screen_y = prev_same_screen_y + 1
    else
	    prev_same_x = 0
	    prev_same_screen_y = 0
	    prev_anchor_y = data.y
    end

    if (prev_same_x <= 20) or (math.abs((data.y-prev_anchor_y)) < 65) then
	    --local curr_distance = math.sqrt((data.x-waypoint_x)^2 + (data.y-waypoint_y)^2)
	    local curr_distance = waypoint_distance_table[current_waypoint] - (math.abs((data.x-waypoint_x)) + math.abs((data.y-waypoint_y)))
    	    local distance_reward = curr_distance*waypoint_reward_scale
	    if distance_reward > prev_max_distance_reward then
	      reward = reward + (distance_reward - prev_max_distance_reward)
	      prev_max_distance_reward = distance_reward
	    end
    end
    
    prev_x = data.x
    prev_y = data.y
    prev_screen_y = data.screen_y

    if level_done >= 1 then
	    reward = reward + (1 - clip(frame_count/frame_limit, 0, 1)) * 1000
    end

    return reward
end