gemini_engine/mesh3d/
components.rs

1use crate::core::ColChar;
2
3/// An alias to [`DVec3`](glam::DVec3), a three-dimensional vector of `f64` values
4pub type Vec3D = glam::DVec3;
5/// An alias to [`DMat4`](glam::DMat4), a 4x4 matrix of `f64` values
6pub type Transform3D = glam::DMat4;
7
8/// A `Face` contains indices to a mesh's collection of vertices and a `ColChar` to fill the face. Indices should be arranged in a clockwise order, as if they appear counter-clockwise when rendering they will not be rendered at all (this is how gemini-engine handles backface culling and maximises performance)
9#[derive(Debug, Clone)]
10pub struct Face {
11    /// The vertex indices of the face
12    pub v_indices: Vec<usize>,
13    /// The desired appearance of the face when rendered
14    pub fill_char: ColChar,
15}
16
17impl Face {
18    /// Create a new face with the given indices and [`ColChar`]
19    #[must_use]
20    pub const fn new(v_indices: Vec<usize>, fill_char: ColChar) -> Self {
21        Self {
22            v_indices,
23            fill_char,
24        }
25    }
26
27    /// Return a vector with the elements found at the vertex indices of the given slice
28    ///
29    /// # Errors
30    /// Will return an error if the passed slice is not long enough to be indexed by the face
31    pub fn index_into<T: Copy>(&self, vertices: &[T]) -> Result<Vec<T>, String> {
32        let mut indexed_vertices = Vec::new();
33        for v_index in &self.v_indices {
34            if let Some(vertex) = vertices.get(*v_index) {
35                indexed_vertices.push(*vertex);
36            } else {
37                return Err(format!(
38                    "Mesh face vertex index ({}) is out of bounds ({})",
39                    v_index,
40                    vertices.len(),
41                ));
42            }
43        }
44        Ok(indexed_vertices)
45    }
46}
gemini_engine/mesh3d/components.rs

gemini_engine/mesh3d/
components.rs
