# Artillery with bounce: a modification of Artillery tutorial

I received an email from Massimo M. – an italian reader – that modified the code explained in Create a flash artillery game – step 1 tutorial.

Massimo wrote:

“Hi, my name is Massy and I browsed your tutorials about Flash games. I think they are very good.

I modified a bit your artillery 8 file adding two rows to the code and obtaining some kind of artillery 9. I am attaching it in case you are interested in publishing it.

I’ve just added elastic bounces to cannon balls when they hit the ground, using a low bounce factor to make it “realistic”.

This is the code to replace in the first frame:

```Mouse.hide();
gravity = 2;
attachMovie("crosshair", "crosshair", 1);
attachMovie("tank", "tank", 2, {_x:230, _y:350});
crosshair.onEnterFrame = function() {
this._x = _xmouse;
this._y = _ymouse;
};
tank.onEnterFrame = function() {
mousex = _xmouse-this._x;
mousey = (_ymouse-this._y)*-1;
angle = Math.atan(mousey/mousex)/(Math.PI/180);
if (mousex<0) {
angle += 180;
}
if (mousex>=0 && mousey<0) {
angle += 360;
}
if (angle>160) {
angle = 160;
}
if (angle<20) {
angle = 20;
}
firepower = Math.sqrt(mousex*mousex+mousey*mousey);
if (firepower>200) {
firepower = 200;
}
this.cannon._rotation = angle*-1;
};
function onMouseDown() {
angle = tank.cannon._rotation-1;
start_ball_x = tank._x+48*Math.cos(angle*Math.PI/180);
start_ball_y = tank._y+48*Math.sin(angle*Math.PI/180);
cannonball_fired = attachMovie("cannonball", "cannonball_"+_root.getNextHighestDepth(), _root.getNextHighestDepth(), {_x:start_ball_x, _y:start_ball_y});
cannonball_fired.dirx = Math.cos(angle*Math.PI/180)*firepower;
cannonball_fired.diry = Math.sin(angle*Math.PI/180)*firepower;
cannonball_fired.onEnterFrame = function() {
this.diry += gravity;
this._x += this.dirx/50;
this._y += this.diry/50;
if (this._y+this._height/2>350) {
this._y = 350-this._height/2;
this.diry = -this.diry*.3;
}
};
}```

and this is what you’ll get:

As you can see, now cannon balls bounce when they hit the ground.

Here it is the zip file with the source code.

Thank you Massimo!

214 GAME PROTOTYPES EXPLAINED WITH SOURCE CODE
// 1+2=3
// 10000000
// 2 Cars
// 2048
// Avoider
// Ballz
// Block it
// Blockage
// Bloons
// Boids
// Bombuzal
// Breakout
// Bricks
// Columns
// CubesOut
// Dots
// DROP'd
// Dudeski
// Eskiv
// Filler
// Fling
// Globe
// HookPod
// Hundreds
// InkTd
// Iromeku
// Lumines
// Magick
// MagOrMin
// Maze
// Memdot
// Nano War
// Nodes
// o:anquan
// Ononmin
// Pacco
// Phyballs
// Platform
// Poker
// Pool
// Poux
// Pudi
// qomp
// Racing
// Renju
// SameGame
// Security
// Sling
// Slingy
// Sokoban
// Splitter
// Sproing
// Stack
// Stringy
// Sudoku
// Tetris
// Threes
// Toony
// Turn
// TwinSpin
// vvvvvv
// Wordle
// Worms
// Yanga
// Zhed
// zNumbers