custom_tree_owned_unsafe/
custom_tree_owned_unsafe.rs

1mod common {
2    pub mod image;
3    pub mod text;
4}
5
6use common::image::{image_measure_function, ImageContext};
7use common::text::{text_measure_function, FontMetrics, TextContext, WritingMode, LOREM_IPSUM};
8use gummy::tree::Cache;
9use gummy::util::print_tree;
10use gummy::{
11    compute_cached_layout, compute_flexbox_layout, compute_grid_layout, compute_leaf_layout, compute_root_layout,
12    prelude::*, round_layout, CacheTree,
13};
14
15#[derive(Debug, Copy, Clone)]
16#[allow(dead_code)]
17enum NodeKind {
18    Flexbox,
19    Grid,
20    Text,
21    Image,
22}
23
24struct Node {
25    kind: NodeKind,
26    style: Style,
27    text_data: Option<TextContext>,
28    image_data: Option<ImageContext>,
29    cache: Cache,
30    unrounded_layout: Layout,
31    pub(crate) has_new_layout: bool,
32    final_layout: Layout,
33    children: Vec<Node>,
34}
35
36impl Default for Node {
37    fn default() -> Self {
38        Node {
39            kind: NodeKind::Flexbox,
40            style: Style::default(),
41            text_data: None,
42            image_data: None,
43            cache: Cache::new(),
44            unrounded_layout: Layout::with_order(0),
45            has_new_layout: false,
46            final_layout: Layout::with_order(0),
47            children: Vec::new(),
48        }
49    }
50}
51
52#[allow(dead_code)]
53impl Node {
54    pub fn new_row(style: Style) -> Node {
55        Node {
56            kind: NodeKind::Flexbox,
57            style: Style { display: Display::Flex, flex_direction: FlexDirection::Row, ..style },
58            ..Node::default()
59        }
60    }
61    pub fn new_column(style: Style) -> Node {
62        Node {
63            kind: NodeKind::Flexbox,
64            style: Style { display: Display::Flex, flex_direction: FlexDirection::Column, ..style },
65            ..Node::default()
66        }
67    }
68    pub fn new_grid(style: Style) -> Node {
69        Node { kind: NodeKind::Grid, style: Style { display: Display::Grid, ..style }, ..Node::default() }
70    }
71    pub fn new_text(style: Style, text_data: TextContext) -> Node {
72        Node { kind: NodeKind::Text, style, text_data: Some(text_data), ..Node::default() }
73    }
74    pub fn new_image(style: Style, image_data: ImageContext) -> Node {
75        Node { kind: NodeKind::Image, style, image_data: Some(image_data), ..Node::default() }
76    }
77    pub fn append_child(&mut self, node: Node) {
78        self.children.push(node);
79    }
80
81    unsafe fn as_id(&self) -> NodeId {
82        NodeId::from(self as *const Node as usize)
83    }
84
85    pub fn compute_layout(&mut self, available_space: Size<AvailableSpace>, use_rounding: bool) {
86        let root_node_id = unsafe { self.as_id() };
87        compute_root_layout(&mut StatelessLayoutTree, root_node_id, available_space);
88        if use_rounding {
89            round_layout(&mut StatelessLayoutTree, root_node_id)
90        }
91    }
92
93    pub fn print_tree(&mut self) {
94        print_tree(&StatelessLayoutTree, unsafe { self.as_id() });
95    }
96}
97
98struct ChildIter<'a>(std::slice::Iter<'a, Node>);
99impl Iterator for ChildIter<'_> {
100    type Item = NodeId;
101    fn next(&mut self) -> Option<Self::Item> {
102        self.0.next().map(|c| NodeId::from(c as *const Node as usize))
103    }
104}
105
106#[inline(always)]
107unsafe fn node_from_id<'a>(node_id: NodeId) -> &'a Node {
108    &*(usize::from(node_id) as *const Node)
109}
110
111#[inline(always)]
112unsafe fn node_from_id_mut<'a>(node_id: NodeId) -> &'a mut Node {
113    &mut *(usize::from(node_id) as *mut Node)
114}
115
116struct StatelessLayoutTree;
117impl TraversePartialTree for StatelessLayoutTree {
118    type ChildIter<'a> = ChildIter<'a>;
119
120    fn child_ids(&self, node_id: NodeId) -> Self::ChildIter<'_> {
121        unsafe { ChildIter(node_from_id(node_id).children.iter()) }
122    }
123
124    fn child_count(&self, node_id: NodeId) -> usize {
125        unsafe { node_from_id(node_id).children.len() }
126    }
127
128    fn get_child_id(&self, node_id: NodeId, index: usize) -> NodeId {
129        unsafe { node_from_id(node_id).children[index].as_id() }
130    }
131}
132
133impl TraverseTree for StatelessLayoutTree {}
134
135impl LayoutPartialTree for StatelessLayoutTree {
136    type CoreContainerStyle<'a>
137        = &'a Style
138    where
139        Self: 'a;
140
141    type CustomIdent = String;
142
143    fn get_core_container_style(&self, node_id: NodeId) -> Self::CoreContainerStyle<'_> {
144        unsafe { &node_from_id(node_id).style }
145    }
146
147    fn set_unrounded_layout(&mut self, node_id: NodeId, layout: &Layout) {
148        unsafe {
149            let node = node_from_id_mut(node_id);
150            node.has_new_layout = &node.unrounded_layout != layout;
151            node.unrounded_layout = *layout;
152        };
153    }
154
155    fn resolve_calc_value(&self, _val: *const (), _basis: f32) -> f32 {
156        0.0
157    }
158
159    fn compute_child_layout(&mut self, node_id: NodeId, inputs: gummy::tree::LayoutInput) -> gummy::tree::LayoutOutput {
160        compute_cached_layout(self, node_id, inputs, |tree, node_id, inputs| {
161            let node = unsafe { node_from_id_mut(node_id) };
162            let font_metrics = FontMetrics { char_width: 10.0, char_height: 10.0 };
163
164            match node.kind {
165                NodeKind::Flexbox => compute_flexbox_layout(tree, node_id, inputs),
166                NodeKind::Grid => compute_grid_layout(tree, node_id, inputs),
167                NodeKind::Text => compute_leaf_layout(
168                    inputs,
169                    &node.style,
170                    |val, basis| tree.resolve_calc_value(val, basis),
171                    |known_dimensions, available_space| {
172                        text_measure_function(
173                            known_dimensions,
174                            available_space,
175                            node.text_data.as_ref().unwrap(),
176                            &font_metrics,
177                        )
178                    },
179                ),
180                NodeKind::Image => compute_leaf_layout(
181                    inputs,
182                    &node.style,
183                    |val, basis| tree.resolve_calc_value(val, basis),
184                    |known_dimensions, _available_space| {
185                        image_measure_function(known_dimensions, node.image_data.as_ref().unwrap())
186                    },
187                ),
188            }
189        })
190    }
191}
192
193impl CacheTree for StatelessLayoutTree {
194    fn cache_get(&self, node_id: NodeId, inputs: &gummy::LayoutInput) -> Option<gummy::LayoutOutput> {
195        unsafe { node_from_id(node_id) }.cache.get(inputs)
196    }
197
198    fn cache_store(&mut self, node_id: NodeId, inputs: &gummy::LayoutInput, layout_output: gummy::LayoutOutput) {
199        unsafe { node_from_id_mut(node_id) }.cache.store(inputs, layout_output)
200    }
201
202    fn cache_clear(&mut self, node_id: NodeId) {
203        unsafe { node_from_id_mut(node_id) }.cache.clear();
204    }
205}
206
207impl gummy::LayoutFlexboxContainer for StatelessLayoutTree {
208    type FlexboxContainerStyle<'a>
209        = &'a Style
210    where
211        Self: 'a;
212
213    type FlexboxItemStyle<'a>
214        = &'a Style
215    where
216        Self: 'a;
217
218    fn get_flexbox_container_style(&self, node_id: NodeId) -> Self::FlexboxContainerStyle<'_> {
219        unsafe { &node_from_id(node_id).style }
220    }
221
222    fn get_flexbox_child_style(&self, child_node_id: NodeId) -> Self::FlexboxItemStyle<'_> {
223        unsafe { &node_from_id(child_node_id).style }
224    }
225}
226
227impl gummy::LayoutGridContainer for StatelessLayoutTree {
228    type GridContainerStyle<'a>
229        = &'a Style
230    where
231        Self: 'a;
232
233    type GridItemStyle<'a>
234        = &'a Style
235    where
236        Self: 'a;
237
238    fn get_grid_container_style(&self, node_id: NodeId) -> Self::GridContainerStyle<'_> {
239        unsafe { &node_from_id(node_id).style }
240    }
241
242    fn get_grid_child_style(&self, child_node_id: NodeId) -> Self::GridItemStyle<'_> {
243        unsafe { &node_from_id(child_node_id).style }
244    }
245}
246
247impl RoundTree for StatelessLayoutTree {
248    fn get_unrounded_layout(&self, node_id: NodeId) -> Layout {
249        unsafe { node_from_id_mut(node_id).unrounded_layout }
250    }
251
252    fn set_final_layout(&mut self, node_id: NodeId, layout: &Layout) {
253        unsafe { node_from_id_mut(node_id).final_layout = *layout }
254    }
255}
256
257impl PrintTree for StatelessLayoutTree {
258    fn get_debug_label(&self, node_id: NodeId) -> &'static str {
259        match unsafe { node_from_id(node_id).kind } {
260            NodeKind::Flexbox => "FLEX",
261            NodeKind::Grid => "GRID",
262            NodeKind::Text => "TEXT",
263            NodeKind::Image => "IMAGE",
264        }
265    }
266
267    fn get_final_layout(&self, node_id: NodeId) -> Layout {
268        unsafe { node_from_id(node_id).final_layout }
269    }
270
271    fn get_has_new_layout(&self, node_id: NodeId) -> bool {
272        unsafe { node_from_id(node_id).has_new_layout }
273    }
274}
275
276fn main() -> Result<(), gummy::GummyError> {
277    let mut root = Node::new_column(Style::DEFAULT);
278
279    let text_node = Node::new_text(
280        Style::default(),
281        TextContext { text_content: LOREM_IPSUM.into(), writing_mode: WritingMode::Horizontal },
282    );
283    root.append_child(text_node);
284
285    let image_node = Node::new_image(Style::default(), ImageContext { width: 400.0, height: 300.0 });
286    root.append_child(image_node);
287
288    // Compute layout and print result
289    root.compute_layout(Size::MAX_CONTENT, true);
290    root.print_tree();
291
292    Ok(())
293}
custom_tree_owned_unsafe/custom_tree_owned_unsafe.rs

custom_tree_owned_unsafe/
custom_tree_owned_unsafe.rs
