draw_vertexs_with_image

// following code is checked in 2016/01/13
// failed to draw vertex now!!
import 'package:flutter/widgets.dart';
import 'package:flutter/rendering.dart';
import 'dart:ui' as sky;
import 'dart:async';
import 'dart:typed_data';
import 'package:flutter/src/services/fetch.dart';
import 'package:flutter/services.dart';
sky.Image img = null;
main() async {
// "assets/icon.jpeg" is error 2015/12/13 's flutter, when draw image
img = await ImageLoader.load("assets/a.png");
runApp(new DrawVertexsWidget());
}
class DrawVertexsWidget extends OneChildRenderObjectWidget {
RenderObject createRenderObject() {
return new DrawVertexsObject();
}
}
class DrawVertexsObject extends RenderBox {
void paint(PaintingContext context, Offset offset) {
context.canvas.translate(50.0, 50.0);
context.canvas.scale(8.0, 8.0);
paintWithImage(context, offset);
}
void paintWithImage(PaintingContext context, Offset offset) {
Paint paint = new Paint();
sky.VertexMode vertexMode = sky.VertexMode.triangleFan;
List<Point> vertices = [
new Point(0.0, 0.0),
new Point(10.0, 50.0),
new Point(50.0, 60.0),
new Point(40.0, 10.0)
];
List<Point> textureCoordinates = [
new Point(0.0, 0.0),
new Point(0.0, 1.0 * img.height),
new Point(1.0 * img.width, 1.0 * img.height),
new Point(1.0 * img.width, 0.0)
];
List<Color> colors = [
const Color.fromARGB(0xaa, 0x00, 0x00, 0xff),
const Color.fromARGB(0xaa, 0x00, 0x00, 0xff),
const Color.fromARGB(0xaa, 0x00, 0x00, 0xff),
const Color.fromARGB(0xaa, 0x00, 0x00, 0xff)
];
sky.TransferMode transferMode = sky.TransferMode.color;
sky.TileMode tmx = sky.TileMode.clamp;
sky.TileMode tmy = sky.TileMode.clamp;
Float64List matrix4 = new Matrix4.identity().storage;
sky.ImageShader imgShader = new sky.ImageShader(img, tmx, tmy, matrix4);
paint.shader = imgShader;
List<int> indicies = [0, 1, 2, 3];
context.canvas.drawVertices(vertexMode, vertices, textureCoordinates,
colors, transferMode, indicies, paint);
}
}
AssetBundle getAssetBundle() {
if (rootBundle != null) {
return rootBundle;
} else {
return new NetworkAssetBundle(new Uri.directory(Uri.base.origin));
}
}
class ImageLoader {
static Future<sky.Image> load(String url) async {
AssetBundle bundle = getAssetBundle();
ImageResource resource = bundle.loadImage(url);
return resource.first;
}
}
# flutter.yaml
assets:
- assets/icon.jpeg
- assets/a.png