1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
//! Shared reusable terrain grid vertex definition.
use bytemuck::{Pod, Zeroable};
/// Vertex for reusable terrain grids.
///
/// Carries only tile-local UV coordinates and a skirt flag. The final
/// world-space position is reconstructed in the shader from tile bounds and
/// GPU-sampled elevation data.
#[repr(C)]
#[derive(Debug, Clone, Copy, Pod, Zeroable)]
pub struct TerrainGridVertex {
/// Tile-local UV in `[0, 1]`.
pub uv: [f32; 2],
/// `0.0` for surface vertices, `1.0` for skirt vertices.
pub skirt: f32,
}
impl TerrainGridVertex {
/// Vertex buffer layout descriptor.
pub fn layout() -> wgpu::VertexBufferLayout<'static> {
wgpu::VertexBufferLayout {
array_stride: std::mem::size_of::<TerrainGridVertex>() as wgpu::BufferAddress,
step_mode: wgpu::VertexStepMode::Vertex,
attributes: &[
wgpu::VertexAttribute {
offset: 0,
shader_location: 0,
format: wgpu::VertexFormat::Float32x2,
},
wgpu::VertexAttribute {
offset: 8,
shader_location: 1,
format: wgpu::VertexFormat::Float32,
},
],
}
}
}