Easy 2D Physics in Flutter

This package makes it easy to use a 2D physical engine in flutter. You can experience acceleration, collision, and rotation.

Installation

1. Add this package to your pubspec.yaml file.

   	dependencies:
   		easy_physics_2d: '^0.0.1'
   

2. Install it.

      $ pub get
   

3. Import.

       import 'package:easy_physics_2d/easy_physics_2d.dart';
   

Usage

	List<dynamic> objList = [];
	var ball;
	
	@override
	void initState(){
		super.initState();
		ball = myBall(  
					xPoint: 100,  
					yPoint: 200,  
					xVelocity: 0,  
					yVelocity: 0,  
					ballRadius: 30,  
					ballMass: 0.5,  
					angularVelocity: 0,  
				);
		objList = [ball];
	}

	GravityField(  
		objects: objList,  
		mapX: 350,  
		mapY: 350,  
		mapColor: Colors.white  
	),

This is the most basic code for using a package. You can add a GravityField widget and add a list of physical objects that you want to put in the field.

	GravityField(  
		objects: objList,  
		gravity: 1000,  
		mapX: 350,  
		mapY: 350,  
		mapColor: Colors.white,
		gravity: 1500,
		frictionConstant: 0.8,
		elasticConstant: 0.9,
	),

You can change the detailed properties of the field by changing gravity, frictionConstant and elasticConstant.

For the ball objects, you can also change designs.

class _HomePageState extends State<HomePage> {  
	Paint paint1 = Paint()  
	  ..color = Color(0xff263e63)  
	  ..style = PaintingStyle.stroke  
	  ..strokeWidth = 2;  

	Paint paint2 = Paint()  
	  ..color = Color(0xff15693b)  
	  ..style = PaintingStyle.stroke  
	  ..strokeWidth = 2;  

	List<Paint> paintList = [];  

	Path draw1 = Path();  
	Path draw2 = Path();  
  
	var ball;  
	var ball2;  
  
	@override  
	void initState() {  
		super.initState();  
		for (double i = 0; i < 20 - 1; i++) {  
			draw1.arcTo(Rect.fromCircle(radius: i, center: Offset(0, 0,)), 0, (1.5 * pi), true);  
			draw2.arcTo(Rect.fromCircle(radius: i, center: Offset(0, 0,)), 1.5 * pi, 0.5 * pi, true);  
		}  

		paintList=[paint1, paint2];  

		ball = myBall(  
		        xPoint: 100,  
				yPoint: 200,  
				xVelocity: 0,  
				yVelocity: 0,  
				ballRadius: 30,  
				ballMass: 0.5,  
				angularVelocity: 0,  
				ballPaint: paintList,
				ballPath: [draw1, draw2], 
		  );  
		ball2 = myBall(  
		        xPoint: 150,  
				yPoint: 100,  
				xVelocity: 0,  
				yVelocity: 0,  
				ballRadius: 20,  
				ballMass: 0.5,  
				angularVelocity: 0,  
				 
		);  
		objList = [ball, ball2];  
	}
}

with the parameter ballPath and ballPaint, you can change Path and Colors of the Ball. At this time, the length of ballPath List and the length of ballPaint List should be the same, and they should be defined in initState.

Each object has the following instance methods, which are easy to use.

var ball = myBall(  
	        xPoint: 100,  
			yPoint: 200,  
			xVelocity: 0,  
			yVelocity: 0,  
			ballRadius: 30,  
			ballMass: 0.5,  
			angularVelocity: 0,  
		); 
		 
double n;
double m;
int range1 = 100;
int range2 = 1500;
double x, y;

ball.addXpos(n); //return void
ball.subXpos(n); //return void
ball.addYpos(n); //return void
ball.subYpos(n); //return void

ball.addXvel(m); //return void
ball.subXvel(m); //return void
ball.addYvel(m); //return void
ball.subYvel(m); //return void

ball.stop(); //return void
ball.shuffle(range1, range2); //return void : set velocity randomly range1 to range2

ball.setPosition(x, y); //return void
ball.addAngle(n); //return void

ball.isBallRegion(x, y); //return true if (x, y) is in Ball area

ball.updateDraw(); //return void: if you want tochange the position, you should run this method.

If you want to move the Ball, please use the instance method to control it.