blob: ce68edef1e1914c535986aa48fef7518a54b643a [file] [log] [blame]
// Copyright 2014 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 'package:flutter/rendering.dart';
import 'framework.dart';
/// A rectangle upon which a backend texture is mapped.
/// Backend textures are images that can be applied (mapped) to an area of the
/// Flutter view. They are created, managed, and updated using a
/// platform-specific texture registry. This is typically done by a plugin
/// that integrates with host platform video player, camera, or OpenGL APIs,
/// or similar image sources.
/// A texture widget refers to its backend texture using an integer ID. Texture
/// IDs are obtained from the texture registry and are scoped to the Flutter
/// view. Texture IDs may be reused after deregistration, at the discretion
/// of the registry. The use of texture IDs currently unknown to the registry
/// will silently result in a blank rectangle.
/// Texture widgets are repainted autonomously as dictated by the backend (e.g.
/// on arrival of a video frame). Such repainting generally does not involve
/// executing Dart code.
/// The size of the rectangle is determined by its parent widget, and the
/// texture is automatically scaled to fit.
/// See also:
/// * <>
/// for how to create and manage backend textures on Android.
/// * <>
/// for how to create and manage backend textures on iOS.
class Texture extends LeafRenderObjectWidget {
/// Creates a widget backed by the texture identified by [textureId], and use
/// [filterQuality] to set texture's [FilterQuality].
const Texture({
required this.textureId,
this.freeze = false,
this.filterQuality = FilterQuality.low,
/// The identity of the backend texture.
final int textureId;
/// When true the texture will not be updated with new frames.
final bool freeze;
/// {@template flutter.widgets.Texture.filterQuality}
/// The quality of sampling the texture and rendering it on screen.
/// When the texture is scaled, a default [FilterQuality.low] is used for a higher quality but slower
/// interpolation (typically bilinear). It can be changed to [FilterQuality.none] for a lower quality but
/// faster interpolation (typically nearest-neighbor). See also [FilterQuality.medium] and
/// [FilterQuality.high] for more options.
/// {@endtemplate}
final FilterQuality filterQuality;
TextureBox createRenderObject(BuildContext context) => TextureBox(textureId: textureId, freeze: freeze, filterQuality: filterQuality);
void updateRenderObject(BuildContext context, TextureBox renderObject) {
renderObject.textureId = textureId;
renderObject.freeze = freeze;
renderObject.filterQuality = filterQuality;