3d tetraedro

gistfile1.txt

import 'package:flutter/material.dart';

import 'dart:math';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Center(
          child: AnimatedTetrahedron(), 
        ),
      ),
    );
  }
}

class AnimatedTetrahedron extends StatefulWidget {
  @override
  _AnimatedTetrahedronState createState() => _AnimatedTetrahedronState();
}

class _AnimatedTetrahedronState extends State<AnimatedTetrahedron>
    with SingleTickerProviderStateMixin {
  
  late AnimationController _controller;
  late Animation<double> _animation;

  @override
  void initState() {  
    super.initState();
    
    _controller = AnimationController(
      vsync: this,
      duration: Duration(seconds: 10),
    )..repeat();

    _animation = Tween(begin: 0.0, end: -pi*2)
        .animate(CurvedAnimation(parent: _controller, curve: Curves.linear)); 
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Center(
          child: Transform(
            transform: Matrix4.rotationZ(_animation.value),
            alignment: Alignment.center,
            child: CustomPaint(
              painter: TetrahedronPainter(_animation.value),
              size: Size(300, 300),
            ),
          ),
        );
      },
    );
  }

  @override 
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

}


class TetrahedronPainter extends CustomPainter {

  final double animation;

  TetrahedronPainter(this.animation);

  @override
  void paint(Canvas canvas, Size size) {
      
    final bluePaint = Paint()..color = Colors.blue..style=PaintingStyle.fill; 
    final redPaint = Paint()..color = Colors.red..style=PaintingStyle.fill;
    final greenPaint = Paint()..color = Colors.green..style = PaintingStyle.fill;
    
    final h = size.height;
    final w = size.width;
   
    final Offset c = Offset(w/2, h*0.6);
    final double len = h * 0.3;
           
    final topPoint    = c + Offset(0 , -len); 
    final leftPoint   = _getCoordinate(c, len, animation);
    final rightPoint  = _getCoordinate(c, len, animation + pi*2/3); 
    final bottomPoint = _getCoordinate(c, len, animation + pi*4/3);
    
    final Path topFace = _createFace(topPoint, leftPoint, rightPoint);
    final Path leftFace = _createFace(topPoint, leftPoint, bottomPoint); 
    final Path rightFace = _createFace(topPoint, rightPoint, bottomPoint);

    canvas.drawPath(topFace, bluePaint);
    canvas.drawPath(leftFace, redPaint);
    canvas.drawPath(rightFace, greenPaint);
     
  }
  
  @override
  bool shouldRepaint(TetrahedronPainter old) => true;

  Offset _getCoordinate(Offset c, double len, double angle){
    return c + Offset(  
      len * cos(angle),
      -len * sin(angle)
    );
  }
  
  Path _createFace(Offset p1, Offset p2, Offset p3){
    final face = Path();
    face.moveTo(p1.dx, p1.dy);
    face.lineTo(p2.dx, p2.dy);
    face.lineTo(p3.dx, p3.dy);
    face.close();
    return face;
  }

}