tests

Author: dnfield

testing/dart/color_filter_test.dart

@@ -0,0 +1,96 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:typed_data';
+import 'dart:ui';
+
+import 'package:test/test.dart';
+
+const Color red = Color(0xFFAA0000);
+const Color green = Color(0xFF00AA00);
+
+const int greenRedColorBlend = 0xFF3131DB;
+const int greenRedColorBlendInverted = 0xFFCECE24;
+const int greenGreyscaled = 0xFF7A7A7A;
+const int greenInvertedGreyscaled = 0xFF858585;
+
+const int greenLinearToSrgbGamma = 0xFF00D500;
+const int greenLinearToSrgbGammaInverted = 0xFFFF2AFF;
+
+const int greenSrgbToLinearGamma = 0xFF006700;
+const int greenSrgbToLinearGammaInverted = 0xFFFF98FF;
+
+const List<double> greyscaleColorMatrix = <double>[
+  0.2126, 0.7152, 0.0722, 0, 0, //
+  0.2126, 0.7152, 0.0722, 0, 0, //
+  0.2126, 0.7152, 0.0722, 0, 0, //
+  0,      0,      0,      1, 0, //
+];
+
+void main() {
+  Future<Uint32List> getBytesForPaint(Paint paint, {int width = 1, int height = 1}) async {
+    final PictureRecorder recorder = PictureRecorder();
+    final Canvas recorderCanvas = Canvas(recorder);
+    recorderCanvas.drawPaint(paint);
+    final Picture picture = recorder.endRecording();
+    final Image image = await picture.toImage(width, height);
+    final ByteData bytes = await image.toByteData();
+
+    expect(bytes.lengthInBytes, width * height * 4);
+    return bytes.buffer.asUint32List();
+  }
+
+  test('ColorFilter - mode', () async {
+    final Paint paint = Paint()
+      ..color = green
+      ..colorFilter = ColorFilter.mode(red, BlendMode.color);
+
+    Uint32List bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenRedColorBlend);
+
+    paint.invertColors = true;
+    bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenRedColorBlendInverted);
+  });
+
+  test('ColorFilter - matrix', () async {
+    final Paint paint = Paint()
+      ..color = green
+      ..colorFilter = ColorFilter.matrix(greyscaleColorMatrix);
+
+    Uint32List bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenGreyscaled);
+
+    paint.invertColors = true;
+    bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenInvertedGreyscaled);
+  });
+
+  test('ColorFilter - linearToSrgbGamma', () async {
+    final Paint paint = Paint()
+      ..color = green
+      ..colorFilter = ColorFilter.linearToSrgbGamma();
+
+    Uint32List bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenLinearToSrgbGamma);
+
+    paint.invertColors = true;
+    bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenLinearToSrgbGammaInverted);
+  });
+
+  test('ColorFilter - srgbToLinearGamma', () async {
+    final Paint paint = Paint()
+      ..color = green
+      ..colorFilter = ColorFilter.srgbToLinearGamma();
+
+    Uint32List bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenSrgbToLinearGamma);
+
+    paint.invertColors = true;
+    bytes = await getBytesForPaint(paint);
+    expect(bytes[0], greenSrgbToLinearGammaInverted);
+  });
+
+}