Initial Thoughts● Single player planned since day one● Multiplayer possibilities for future games● Unit personality● Destructible planets● AI quality important● Cheap gameplay ● Medals, achievements & rewards
Destructible Planets (1 of 3)● Each planet originally a bitmap, with explosions being removed from the bitmap ● Simple implementation ● How to get units to walk around planets correctly? ● How to calculate the new planets mass after an explosion?
Destructible Planets (2 of 3)● Planet shape stored as a series of points ● Planets made up of about 40 points● Units walk around by following the line represented by two consecutive points● Shape drawn to a Movieclip then used as a mask over the planet graphic● Vector representation means mass easily calculated
Destructible Planets (3 of 3)● When a planet is hit, another series of points representing explosions created● Function takes the explosion and planet shapes and cuts the explosion shape out of the planet ● Calculates intersections between the shapes ● Walks around each shape until it intersects the other shape, then switch shape and continue until back to origin
Cheap Gameplay● Wanted to use cheap gameplay to keep players playing ● Better medals awarded for better scores ● Achievements ● Rewards – New weapons – Unit victory and idle animations – Features (old school GFX, infinite ammo)
Unit Movement● Units can walk around planet CW/CCW● Started with Right = CW, Left = CCW ● Makes less sense when at the bottom of a planet● Decided to try to guess which way the player wanted to move ● At top of planet R = CW, L = CCW ● At bottom of planet L = CW, R = CCW
Artificial Intelligence (1 of 2)● No experience with AI!● Various stages ● Are there any pickups I can get? ● Am I directly in the line of sight of enemies? If so, is there somewhere I can retreat to after shooting that isnt? ● Gravity set up too complicated to work out a power & angle to guarantee a hit.
Artificial Intelligence (2 of 2)● AI throws out 720 different shots (72 different angles, 10 different powers)● AI decides on which of those shots to take, based on who can be hit, how much health they have and what weapons are available● Each enemy team has an accuracy score. Shots are knocked off by a random amount, based on this score.● Originally if the AI couldnt hit an enemy it would move or teleport to another planet and try again
Response Overview● Very well received!● Hit the 1m gameplay mark after 6 days● Total plays to date approx 12m – 15m● Current Ratings ● Newgrounds – 4.42 (Top 50 for a while) ● Kongregate – 4.40 (Best of Nov 2010)
User Complaints (1 of 3)● AI Flaws ● Enemies take too long thinking – fixed ● Enemies walk over mines ● Enemies are too accurate with their shots ● Enemies dont use all of the weapons
User Complaints (2 of 3)● Balancing issues ● Why dont the AI teams shoot at each other? ● Money cheat – end score based on health remaining and damage done ● After earning enough money, its easy to just meteor strike and nuke the enemy to death
User Complaints (3 of 3)● Miscellaneous ● Intuitive movement – hard to control ● No multiplayer yet!