rustial_engine/visualization/
grid_scalar_layer.rs

1//! Flat georeferenced colour grid overlay layer.
2
3use std::any::Any;
4
5use crate::layer::{Layer, LayerId, LayerKind};
6use super::{ColorRamp, GeoGrid, ScalarField2D};
7
8/// A flat georeferenced colour grid overlay.
9///
10/// Each grid cell is coloured by evaluating the [`ColorRamp`] at the
11/// cell's normalised [`ScalarField2D`] value.
12///
13/// This layer participates in the standard `MapState::pick` system:
14/// a geographic pick query resolves to the grid cell via
15/// [`GeoGrid::cell_at_geo`] and returns the cell index and scalar
16/// value in the [`PickHit`](crate::picking::PickHit) result.
17#[derive(Debug, Clone)]
18pub struct GridScalarLayer {
19    id: LayerId,
20    name: String,
21    visible: bool,
22    opacity: f32,
23    z_index: i32,
24    /// Grid geometry.
25    pub grid: GeoGrid,
26    /// Scalar field values.
27    pub field: ScalarField2D,
28    /// Colour transfer function.
29    pub ramp: ColorRamp,
30}
31
32impl GridScalarLayer {
33    /// Create a new grid scalar layer.
34    pub fn new(
35        name: impl Into<String>,
36        grid: GeoGrid,
37        field: ScalarField2D,
38        ramp: ColorRamp,
39    ) -> Self {
40        Self {
41            id: LayerId::next(),
42            name: name.into(),
43            visible: true,
44            opacity: 1.0,
45            z_index: 0,
46            grid,
47            field,
48            ramp,
49        }
50    }
51
52    /// Replace the scalar field values (value-only update).
53    pub fn update_field(&mut self, data: Vec<f32>) {
54        self.field.update_values(data);
55    }
56}
57
58impl Layer for GridScalarLayer {
59    fn id(&self) -> LayerId {
60        self.id
61    }
62
63    fn name(&self) -> &str {
64        &self.name
65    }
66
67    fn kind(&self) -> LayerKind {
68        LayerKind::Visualization
69    }
70
71    fn visible(&self) -> bool {
72        self.visible
73    }
74
75    fn set_visible(&mut self, visible: bool) {
76        self.visible = visible;
77    }
78
79    fn opacity(&self) -> f32 {
80        self.opacity
81    }
82
83    fn set_opacity(&mut self, opacity: f32) {
84        self.opacity = opacity.clamp(0.0, 1.0);
85    }
86
87    fn z_index(&self) -> i32 {
88        self.z_index
89    }
90
91    fn as_any(&self) -> &dyn Any {
92        self
93    }
94
95    fn as_any_mut(&mut self) -> &mut dyn Any {
96        self
97    }
98}
99
100#[cfg(test)]
101mod tests {
102    use super::*;
103    use crate::visualization::ColorStop;
104    use rustial_math::GeoCoord;
105
106    fn test_ramp() -> ColorRamp {
107        ColorRamp::new(vec![
108            ColorStop { value: 0.0, color: [0.0, 0.0, 1.0, 1.0] },
109            ColorStop { value: 1.0, color: [1.0, 0.0, 0.0, 1.0] },
110        ])
111    }
112
113    #[test]
114    fn grid_scalar_layer_basics() {
115        let grid = GeoGrid::new(GeoCoord::from_lat_lon(0.0, 0.0), 4, 4, 100.0, 100.0);
116        let field = ScalarField2D::from_data(4, 4, vec![0.0; 16]);
117        let layer = GridScalarLayer::new("density", grid, field, test_ramp());
118        assert_eq!(layer.name(), "density");
119        assert!(layer.visible());
120        assert!((layer.opacity() - 1.0).abs() < f32::EPSILON);
121        assert_eq!(layer.kind(), LayerKind::Visualization);
122    }
123
124    #[test]
125    fn grid_scalar_layer_id_stable() {
126        let grid = GeoGrid::new(GeoCoord::from_lat_lon(0.0, 0.0), 2, 2, 10.0, 10.0);
127        let field = ScalarField2D::from_data(2, 2, vec![1.0; 4]);
128        let layer = GridScalarLayer::new("test", grid, field, test_ramp());
129        assert_eq!(layer.id(), layer.id());
130    }
131
132    #[test]
133    fn grid_scalar_layer_downcast() {
134        let grid = GeoGrid::new(GeoCoord::from_lat_lon(0.0, 0.0), 2, 2, 10.0, 10.0);
135        let field = ScalarField2D::from_data(2, 2, vec![1.0; 4]);
136        let layer: Box<dyn Layer> = Box::new(GridScalarLayer::new("test", grid, field, test_ramp()));
137        assert!(layer.as_any().downcast_ref::<GridScalarLayer>().is_some());
138    }
139
140    #[test]
141    fn update_field_bumps_value_generation() {
142        let grid = GeoGrid::new(GeoCoord::from_lat_lon(0.0, 0.0), 2, 2, 10.0, 10.0);
143        let field = ScalarField2D::from_data(2, 2, vec![0.0; 4]);
144        let mut layer = GridScalarLayer::new("test", grid, field, test_ramp());
145        assert_eq!(layer.field.value_generation, 0);
146        layer.update_field(vec![1.0; 4]);
147        assert_eq!(layer.field.value_generation, 1);
148    }
149}
rustial_engine/visualization/grid_scalar_layer.rs

rustial_engine/visualization/
grid_scalar_layer.rs
