Macro mesh 

mesh!() { /* proc-macro */ }

Convenience macro to quickly create a small mesh.

Examples

Here we create two triangles:

use lox::{
    mesh,
    prelude::*,
    core::SharedVertexMesh,
};


let (mesh, positions, distances, face_colors) = mesh! {
    type: SharedVertexMesh,
    vertices: [
        v0: ([0.0, 0.0, 0.0], 0.0),
        v1: ([0.0, 1.0, 0.0], 1.0),
        v2: ([1.0, 0.0, 0.0], 1.0),
        v3: ([1.0, 1.0, 0.0], 1.414),
    ],
    faces: [
        [v0, v2, v1]: ("red"),
        [v3, v1, v2]: ("green"),
    ],
};

assert_eq!(mesh.num_vertices(), 4);
assert_eq!(mesh.num_faces(), 2);

In the code above, we associate a position and a scalar value with each vertex and a color (or rather, a color name) with each face. Properties of vertices and faces are specified after a colon (:) in parenthesis (like a tuple).

For each property you add in those parenthesis, the macro returns an additional property map. The full return value is:

(mesh, /* vertex property maps */, /* face property maps*/)

Without properties

We don’t need to specify any properties. We can either write empty parenthesis (()) or just omit the colon and the parenthesis:

use lox::{
    mesh,
    core::SharedVertexMesh,
};


let mesh = mesh! {
    type: SharedVertexMesh,
    vertices: [
        v0: (),  // <-- this is equivalent to:
        v1,      // <-- this
        v2,
        v3,
    ],
    faces: [
        [v0, v2, v1],
        [v3, v1, v2],
    ],
};

Of course, you can also add properties to the vertices, but not the faces, or the other way around. However, you always have to specify the same number of properties for all vertices and the same number of properties for all faces.

An empty mesh

This is not particularly useful in itself, but it works. You can use this syntax when you haven’t yet decided how your mesh should look like.

use lox::{
    mesh,
    core::SharedVertexMesh,
};


let empty_mesh = mesh! {
    type: SharedVertexMesh,
    vertices: [],
    faces: [],
};