FragmentShader setImageSampler doesn't support FilterQuality #133944
Description
Is there an existing issue for this?
- I have searched the existing issues
- I have read the guide to filing a bug
Steps to reproduce
- Generate a
ui.Imagein code usingUint8List,ImageDescriptor.raw, codec, etc. - Create a
FragmentShaderthat accepts a uniform sampler2D - Pass the image into the shader using
setImageSampler - Render the shader, reading directly from the sampler
Expected results
I would expect to have a choice of FilterQuality for the texture, but I can't find any such interface. Scaled-up texture should have a smooth, interpolated appearance.
Actual results
Image is pixelated (nearest neighbor)
Code sample
Code sample
import 'dart:typed_data';
import 'dart:ui' as ui;
import 'package:flutter/material.dart';
void main() async {
final program = await ui.FragmentProgram.fromAsset('assets/texture.frag');
final image = await makeImage();
runApp(MyApp(image, program));
}
class MyApp extends StatelessWidget {
final ui.FragmentProgram program;
final ui.Image image;
const MyApp(this.image, this.program, {super.key});
@override
Widget build(BuildContext context) {
const title = 'Texture Demo';
return MaterialApp(
title: title,
theme: ThemeData(
colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
useMaterial3: true,
),
home: Scaffold(
appBar: AppBar(
backgroundColor: Theme.of(context).colorScheme.inversePrimary,
title: const Text(title),
),
body: CustomPaint(
size: Size.infinite,
painter: TexturePainter(image, program.fragmentShader()),
),
),
);
}
}
class TexturePainter extends CustomPainter {
final ui.Image image;
final ui.FragmentShader shader;
TexturePainter(this.image, this.shader);
@override
void paint(Canvas canvas, Size size) {
debugPrint('picture of size $size');
shader.setFloat(0, size.width);
shader.setFloat(1, size.height);
shader.setImageSampler(0, image);
canvas.drawRect(Offset.zero & size, Paint()..shader = shader);
}
@override
bool shouldRepaint(TexturePainter oldDelegate) =>
shader != oldDelegate.shader;
}
Future<ui.Image> makeImage() async {
const width = 64;
const height = 64;
const bytesPerPixel = 4;
final buffer = Uint8List(width * height * bytesPerPixel);
for (int y = 0; y < height; y++) {
for (int x = 0; x < height; x++) {
final offset = ((y * width) + x) * bytesPerPixel;
final parity = (x % 2) ^ (y % 2) != 0;
buffer[offset + 1] = parity ? 255 : 0;
buffer[offset + 2] = parity ? 200 : 0;
buffer[offset + 3] = 255;
}
}
final immutable = await ui.ImmutableBuffer.fromUint8List(buffer);
final descriptor = ui.ImageDescriptor.raw(
immutable,
width: width,
height: height,
pixelFormat: ui.PixelFormat.rgba8888,
);
final codec = await descriptor.instantiateCodec(
targetWidth: width,
targetHeight: height,
);
final frameInfo = await codec.getNextFrame();
return frameInfo.image;
}pubspec.yaml:
shaders:
- assets/texture.frag
texture.frag:
#version 460 core
#include <flutter/runtime_effect.glsl>
uniform vec2 uSize;
uniform sampler2D uSampler;
out vec4 fragColor;
void main() {
vec2 uv = FlutterFragCoord() / uSize;
fragColor = texture(uSampler, uv);
}Screenshots or Video
Screenshots / Video demonstration
Logs
Logs
% flutter run --verbose -d macos
[ +1 ms] executing: [/Users/pc/fvm/versions/3.10.2/] git -c log.showSignature=false log -n 1 --pretty=format:%H
[ +19 ms] Exit code 0 from: git -c log.showSignature=false log -n 1 --pretty=format:%H
[ ] 9cd3d0d9ff05768afa249e036acc66e8abe93bff
[ ] executing: [/Users/pc/fvm/versions/3.10.2/] git tag --points-at 9cd3d0d9ff05768afa249e036acc66e8abe93bff
[ +89 ms] Exit code 0 from: git tag --points-at 9cd3d0d9ff05768afa249e036acc66e8abe93bff
[ ] 3.10.2
[ +1 ms] executing: [/Users/pc/fvm/versions/3.10.2/] git rev-parse --abbrev-ref HEAD
[ +8 ms] Exit code 0 from: git rev-parse --abbrev-ref HEAD
[ ] stable
[ ] executing: sw_vers -productName
[ +10 ms] Exit code 0 from: sw_vers -productName
[ ] macOS
[ ] executing: sw_vers -productVersion
[ +8 ms] Exit code 0 from: sw_vers -productVersion
[ ] 13.5.1
[ ] executing: sw_vers -buildVersion
[ +11 ms] Exit code 0 from: sw_vers -buildVersion
[ ] 22G90
[ ] executing: uname -m
[ +5 ms] Exit code 0 from: uname -m
[ ] arm64
[ +7 ms] executing: sysctl hw.optional.arm64
[ +6 ms] Exit code 0 from: sysctl hw.optional.arm64
[ ] hw.optional.arm64: 1
[ +11 ms] Unable to locate an Android SDK.
[ +1 ms] executing: [/Users/pc/fvm/versions/3.10.2/] git rev-parse --abbrev-ref --symbolic @{upstream}
[ +8 ms] Exit code 0 from: git rev-parse --abbrev-ref --symbolic @{upstream}
[ ] origin/stable
[ ] executing: [/Users/pc/fvm/versions/3.10.2/] git ls-remote --get-url origin
[ +7 ms] Exit code 0 from: git ls-remote --get-url origin
[ ] https://github.com/flutter/flutter.git
[ +41 ms] executing: sysctl hw.optional.arm64
[ +6 ms] Exit code 0 from: sysctl hw.optional.arm64
[ ] hw.optional.arm64: 1
[ ] executing: /usr/bin/arch -arm64e xcrun xcodebuild -version
[ +185 ms] Exit code 0 from: /usr/bin/arch -arm64e xcrun xcodebuild -version
[ ] Xcode 14.3.1
Build version 14E300c
[ +1 ms] executing: /usr/bin/arch -arm64e xcrun xcdevice list --timeout 5
...Flutter Doctor output
Doctor output
[✓] Flutter (Channel stable, 3.10.2, on macOS 13.5.1 22G90 darwin-arm64, locale en-CA)
• Flutter version 3.10.2 on channel stable at /Users/pc/fvm/versions/3.10.2
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision 9cd3d0d9ff (3 months ago), 2023-05-23 20:57:28 -0700
• Engine revision 90fa3ae28f
• Dart version 3.0.2
• DevTools version 2.23.1
[✗] Android toolchain - develop for Android devices
✗ Unable to locate Android SDK.
Install Android Studio from: https://developer.android.com/studio/index.html
On first launch it will assist you in installing the Android SDK components.
(or visit https://flutter.dev/docs/get-started/install/macos#android-setup for detailed instructions).
If the Android SDK has been installed to a custom location, please use
`flutter config --android-sdk` to update to that location.
[✓] Xcode - develop for iOS and macOS (Xcode 14.3.1)
• Xcode at /Applications/Xcode.app/Contents/Developer
• Build 14E300c
• CocoaPods version 1.12.1
[✓] Chrome - develop for the web
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
[!] Android Studio (not installed)
• Android Studio not found; download from https://developer.android.com/studio/index.html
(or visit https://flutter.dev/docs/get-started/install/macos#android-setup for detailed instructions).
[✓] VS Code (version 1.81.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.70.0
[✓] Connected device (2 available)
• macOS (desktop) • macos • darwin-arm64 • macOS 13.5.1 22G90 darwin-arm64
• Chrome (web) • chrome • web-javascript • Google Chrome 116.0.5845.140
[✓] Network resources
• All expected network resources are available.
! Doctor found issues in 2 categories.