JavaScript-Pool-Game-Tutorial/Ball.js at master · henshmi/JavaScript-Pool-Game-Tutorial · GitHub

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functionBall(position,color){
this.position=position;
this.velocity=newVector2();
this.moving=false;
this.sprite=getBallSpriteByColor(color);
this.color=color;
this.visible=true;
}

Ball.prototype.update=function(delta){

if(!this.visible){
return;
}

this.position.addTo(this.velocity.mult(delta));

// Apply friction
this.velocity=this.velocity.mult(1-CONSTANTS.frictionEnergyLoss);

if(this.velocity.length()<CONSTANTS.minVelocityLength){
this.velocity=newVector2();
this.moving=false;
}
}

Ball.prototype.draw=function(){

if(!this.visible){
return;
}

Canvas.drawImage(this.sprite,this.position,CONSTANTS.ballOrigin);
}

Ball.prototype.shoot=function(power,rotation){

this.velocity=newVector2(power*Math.cos(rotation),power*Math.sin(rotation));
this.moving=true;
}

Ball.prototype.collideWithBall=function(ball){

if(!this.visible||!ball.visible){
return;
}

// Find a normal vector
constn=this.position.subtract(ball.position);

// Find distance
constdist=n.length();

if(dist>CONSTANTS.ballDiameter){
return;
}

// Find minimum translation distance
constmtd=n.mult((CONSTANTS.ballDiameter-dist)/dist);

// Push-pull balls apart
this.position=this.position.add(mtd.mult(1/2));
ball.position=ball.position.subtract(mtd.mult(1/2));

// Find unit normal vector
constun=n.mult(1/n.length());

// Find unit tangent vector
constut=newVector2(-un.y,un.x);

// Project velocities onto the unit normal and unit tangent vectors
constv1n=un.dot(this.velocity);
constv1t=ut.dot(this.velocity);
constv2n=un.dot(ball.velocity);
constv2t=ut.dot(ball.velocity);

// Find new normal velocities
letv1nTag=v2n;
letv2nTag=v1n;

// Convert the scalar normal and tangential velocities into vectors
v1nTag=un.mult(v1nTag);
constv1tTag=ut.mult(v1t);
v2nTag=un.mult(v2nTag);
constv2tTag=ut.mult(v2t);

// Update velocities
this.velocity=v1nTag.add(v1tTag);
ball.velocity=v2nTag.add(v2tTag);

this.moving=true;
ball.moving=true;

}

Ball.prototype.handleBallInPocket=function(){

if(!this.visible){
return;
}

letinPocket=CONSTANTS.pockets.some(pocket=>{
returnthis.position.distFrom(pocket)<CONSTANTS.pocketRadius;
});

if(!inPocket){
return;
}

this.visible=false;
this.moving=false;
}

Ball.prototype.collideWithTable=function(table){

if(!this.moving||!this.visible){
return;
}

letcollided=false;

if(this.position.y<=table.TopY+CONSTANTS.ballRadius){
this.position.y=table.TopY+CONSTANTS.ballRadius;
this.velocity=newVector2(this.velocity.x,-this.velocity.y);
collided=true;
}

if(this.position.x>=table.RightX-CONSTANTS.ballRadius){
this.position.x=table.RightX-CONSTANTS.ballRadius;
this.velocity=newVector2(-this.velocity.x,this.velocity.y);
collided=true;
}

if(this.position.y>=table.BottomY-CONSTANTS.ballRadius){
this.position.y=table.BottomY-CONSTANTS.ballRadius;
this.velocity=newVector2(this.velocity.x,-this.velocity.y);
collided=true;
}

if(this.position.x<=table.LeftX+CONSTANTS.ballRadius){
this.position.x=table.LeftX+CONSTANTS.ballRadius;
this.velocity=newVector2(-this.velocity.x,this.velocity.y);
collided=true;
}

if(collided){
this.velocity=this.velocity.mult(1-CONSTANTS.collisionEnergyLoss);
}

}