fission_core/ui/widgets/
image.rs

1use crate::internal::InternalLower;
2use crate::lowering::{InternalIrBuilder, InternalLoweringCx};
3use fission_ir::{
4    op::{ImageFit, LayoutOp, Op, PaintOp},
5    WidgetId,
6};
7use serde::{Deserialize, Serialize};
8
9pub use fission_ir::op::{
10    HttpHeader, ImageAlignment, ImageCachePolicy, ImageErrorBehavior, ImageLoadingBehavior,
11    ImageRequest, ImageSource,
12};
13
14/// Displays an image from an asset, file, network URL, memory buffer, or inline SVG.
15///
16/// `Image` is declarative: it describes the image source and presentation. The
17/// active shell is responsible for loading, decoding, caching, and repainting
18/// when the image becomes available.
19#[derive(Debug, Clone, Serialize, Deserialize)]
20pub struct Image {
21    /// Explicit node identity.
22    pub id: Option<WidgetId>,
23    /// Typed image request consumed by the shell image pipeline.
24    pub request: ImageRequest,
25    /// Fixed width in layout points.
26    pub width: Option<f32>,
27    /// Fixed height in layout points.
28    pub height: Option<f32>,
29    /// How the image is scaled to fit its layout box.
30    pub fit: ImageFit,
31    /// How fitted image content is positioned inside its layout box.
32    pub alignment: ImageAlignment,
33}
34
35impl Default for Image {
36    fn default() -> Self {
37        Self {
38            id: None,
39            request: ImageRequest::default(),
40            width: None,
41            height: None,
42            fit: ImageFit::Contain,
43            alignment: ImageAlignment::Center,
44        }
45    }
46}
47
48impl Image {
49    pub fn asset(path: impl Into<String>) -> Self {
50        Self::from_source(ImageSource::Asset { path: path.into() })
51    }
52
53    pub fn file(path: impl Into<String>) -> Self {
54        Self::from_source(ImageSource::File { path: path.into() })
55    }
56
57    pub fn network(url: impl Into<String>) -> Self {
58        Self::from_source(ImageSource::Network {
59            url: url.into(),
60            headers: Vec::new(),
61            cache_policy: ImageCachePolicy::Default,
62        })
63    }
64
65    pub fn memory(bytes: impl Into<Vec<u8>>) -> Self {
66        Self::from_source(ImageSource::Memory {
67            bytes: bytes.into(),
68            mime_type: None,
69        })
70    }
71
72    pub fn svg_text(content: impl Into<String>) -> Self {
73        Self::from_source(ImageSource::SvgText {
74            content: content.into(),
75        })
76    }
77
78    pub fn from_source(source: ImageSource) -> Self {
79        Self {
80            request: ImageRequest {
81                source,
82                ..Default::default()
83            },
84            ..Default::default()
85        }
86    }
87
88    pub fn width(mut self, width: f32) -> Self {
89        self.width = Some(width);
90        self
91    }
92
93    pub fn height(mut self, height: f32) -> Self {
94        self.height = Some(height);
95        self
96    }
97
98    pub fn size(mut self, width: f32, height: f32) -> Self {
99        self.width = Some(width);
100        self.height = Some(height);
101        self
102    }
103
104    pub fn fit(mut self, fit: ImageFit) -> Self {
105        self.fit = fit;
106        self
107    }
108
109    pub fn alignment(mut self, alignment: ImageAlignment) -> Self {
110        self.alignment = alignment;
111        self
112    }
113
114    pub fn semantic_label(mut self, label: impl Into<String>) -> Self {
115        self.request.semantic_label = Some(label.into());
116        self
117    }
118
119    pub fn cache_size(mut self, width: u32, height: u32) -> Self {
120        self.request.cache_width = Some(width);
121        self.request.cache_height = Some(height);
122        self
123    }
124
125    pub fn loading(mut self, loading: ImageLoadingBehavior) -> Self {
126        self.request.loading = loading;
127        self
128    }
129
130    pub fn error(mut self, error: ImageErrorBehavior) -> Self {
131        self.request.error = error;
132        self
133    }
134
135    pub fn header(mut self, name: impl Into<String>, value: impl Into<String>) -> Self {
136        if let ImageSource::Network { headers, .. } = &mut self.request.source {
137            headers.push(HttpHeader {
138                name: name.into(),
139                value: value.into(),
140            });
141        }
142        self
143    }
144
145    pub fn cache_policy(mut self, cache_policy: ImageCachePolicy) -> Self {
146        if let ImageSource::Network {
147            cache_policy: policy,
148            ..
149        } = &mut self.request.source
150        {
151            *policy = cache_policy;
152        }
153        self
154    }
155}
156
157impl InternalLower for Image {
158    fn lower(&self, cx: &mut InternalLoweringCx) -> WidgetId {
159        let layout_id = self.id.map(Into::into).unwrap_or_else(|| cx.next_node_id());
160        let paint_op = match &self.request.source {
161            ImageSource::SvgText { content } => PaintOp::DrawSvg {
162                content: content.clone(),
163                fill: None,
164                stroke: None,
165            },
166            _ => PaintOp::DrawImage {
167                request: self.request.clone(),
168                fit: self.fit,
169                alignment: self.alignment,
170            },
171        };
172        let paint_id = InternalIrBuilder::new(cx.next_node_id(), Op::Paint(paint_op)).build(cx);
173
174        let mut layout_builder = InternalIrBuilder::new(
175            layout_id,
176            Op::Layout(LayoutOp::Box {
177                width: self.width,
178                height: self.height,
179                min_width: None,
180                max_width: None,
181                min_height: None,
182                max_height: None,
183                padding: [0.0; 4],
184                flex_grow: 0.0,
185                flex_shrink: 0.0,
186                aspect_ratio: None,
187            }),
188        );
189        layout_builder.add_child(paint_id);
190        layout_builder.build(cx)
191    }
192}
fission_core/ui/widgets/image.rs

fission_core/ui/widgets/
image.rs
