memo_flutter.draw_vertexs.lib.main.dart

import 'package:flutter/widgets.dart' as sky;
import 'package:flutter/painting.dart' as sky;
import 'package:flutter/rendering.dart' as sky;
import 'dart:ui' as skyui;

void main() {
  sky.runApp(new DemoWidget());
}

class DemoWidget extends sky.SingleChildRenderObjectWidget {
  @override
  sky.RenderObject createRenderObject(sky.BuildContext context) {
    return new DemoObject();
  }
}

class DemoObject extends sky.RenderConstrainedBox {
  DemoObject() : super(additionalConstraints: const sky.BoxConstraints.expand()) {
    ;
  }

  @override
  bool hitTestSelf(skyui.Offset position) => true;

  @override
  void handleEvent(sky.PointerEvent event, sky.BoxHitTestEntry entry) {}

  @override
  void paint(sky.PaintingContext context, sky.Offset offset) {
    sky.Paint paint = new sky.Paint();
    skyui.VertexMode vertexMode = skyui.VertexMode.triangles;
    List<skyui.Offset> verticesSrc = [
      new skyui.Offset(50.0, 50.0),
      new skyui.Offset(100.0, 400.0),
      new skyui.Offset(350.0, 300.0)
    ];
    List<skyui.Offset> textureCoordinates = [];
    List<sky.Color> colors = [
      const sky.Color.fromARGB(0xaa, 0xff, 0x00, 0x00),
      const sky.Color.fromARGB(0xaa, 0x00, 0xff, 0x00),
      const sky.Color.fromARGB(0xaa, 0x00, 0x00, 0xff)
    ];
    List<int> indicies = [0, 1, 2];
    skyui.Vertices vertices = new skyui.Vertices(vertexMode, verticesSrc,colors: colors, indices: indicies);
    context.canvas.drawVertices(vertices, skyui.BlendMode.color, paint);
  }
}