Math, Physics, and Animation - HTML5 Canvas - page 442

, b2DebugDraw = Box2D . Dynamics . b2DebugDraw ;

var var world = new new b2World ( new new b2Vec2 ( 0 , 20 ), true true );

var var numBoxes = 8 ;

var var boxes = new new Array ();

var var balls = new new Array ();

var var boxHeight = 25 ;

var var boxWidth = 25 ;

var

var startX = ( theCanvas . width - 100 );
var

var startY = ( theCanvas . height - boxHeight ) - 100
for

for ( var var i = 0 ; i < numBoxes ; i ++ ) {

var

var boxDef = new new b2BodyDef ;

boxDef . type = b2Body . b2_dynamicBody ;
var var ypos = ( startY - ( i * boxHeight )) / scaleFactor ;

var var xpos = ( startX ) / scaleFactor ;

boxDef . position . Set ( xpos , ypos );
var var newBox = world . CreateBody ( boxDef )

var

var boxFixture = new new b2FixtureDef ;

boxFixture . density = 20.0 ;
boxFixture . friction = . 5 ;
boxFixture . restitution = . 1 ;
boxFixture . shape = new

new b2PolygonShape ;
boxFixture . shape . SetAsBox (( boxWidth / scaleFactor ) / 2 ,
( boxHeight / scaleFactor ) / 2 );
newBox . CreateFixture ( boxFixture );
newBox . SetUserData ({ width : boxWidth / scaleFactor ,
height : boxHeight / scaleFactor })
boxes . push ( newBox );

}

var var wallDefs = new new Array (

{ x : theCanvas . width , y : 0 , w : theCanvas . width , h : 1 }, //top
{ x : theCanvas . width , y : theCanvas . height , w : theCanvas . width , h : 1 }, //bottom
{ x : 0 , y : theCanvas . height , w : 1 , h : theCanvas . height }, //left
{ x : theCanvas . width , y : theCanvas . height , w : 1 , h : theCanvas . height } ); //right

var var walls = new new Array ();

for for ( var var i = 0 ; i < wallDefs . length ; i ++ ) {

var var wallDef = new new b2BodyDef ;

wallDef . type = b2Body . b2_staticBody ;
wallDef . position . Set ( wallDefs [ i ]. x / scaleFactor , wallDefs [ i ]. y / scaleFactor );
var

var newWall = world . CreateBody ( wallDef )
var var wallFixture = new new b2FixtureDef ;

wallFixture . density = 10.0 ;
wallFixture . friction = 0.5 ;
wallFixture . restitution = . 5 ;
wallFixture . shape = new

new b2PolygonShape ;