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Feature/glam cross constants #21561

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cf4b1dd
add CARDINALS constant to Dir2 and Dir3
Oct 16, 2025
9b2e9e1
added the DIAGONALS const
Oct 16, 2025
c10d08f
added ALL_NEIGHBORS constant
Oct 16, 2025
35ab172
applied formatter to new changes
Oct 16, 2025
a913e2b
fix clippy warning about precision
Oct 16, 2025
003b605
updated the 1/sqrt(3) const to be in line with the unstable rust defi…
Oct 16, 2025
99986cc
added reason for allow of excessive precision
Oct 16, 2025
4be20e8
replaced allow with expect as per CI hint
Oct 16, 2025
ddf0d5a
formatting and typo fixes
Oct 16, 2025
91452e2
added ALL_EDGES group and fixed the ALL_NEIGHBORS to have all the nei…
pin3free Oct 17, 2025
f6c1789
fix documentation terminology for neighbors
pin3free Oct 17, 2025
621263b
fix typos
pin3free Oct 17, 2025
a8f891d
Update crates/bevy_math/src/direction.rs
pine-free Oct 17, 2025
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158 changes: 158 additions & 0 deletions crates/bevy_math/src/direction.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -107,6 +107,8 @@ impl Dir2 {
pub const NEG_Y: Self = Self(Vec2::NEG_Y);
/// The directional axes.
pub const AXES: [Self; 2] = [Self::X, Self::Y];
/// The cardinal directions.
pub const CARDINALS: [Self; 4] = [Self::X, Self::NEG_X, Self::Y, Self::NEG_Y];

/// The "north" direction, equivalent to [`Dir2::Y`].
pub const NORTH: Self = Self(Vec2::Y);
Expand All @@ -125,6 +127,25 @@ impl Dir2 {
/// The "south-west" direction, between [`Dir2::SOUTH`] and [`Dir2::WEST`].
pub const SOUTH_WEST: Self = Self(Vec2::new(-FRAC_1_SQRT_2, -FRAC_1_SQRT_2));

/// The diagonals between the cardinal directions.
pub const DIAGONALS: [Self; 4] = [
Self::NORTH_EAST,
Self::NORTH_WEST,
Self::SOUTH_EAST,
Self::SOUTH_WEST,
];
/// All neighbors of a tile on a square grid in a 3x3 neighborhood. A combination of [`Self::CARDINALS`] and [`Self::DIAGONALS`]
pub const ALL_NEIGHBORS: [Self; 8] = [
Self::X,
Self::NEG_X,
Self::Y,
Self::NEG_Y,
Self::NORTH_EAST,
Self::NORTH_WEST,
Self::SOUTH_EAST,
Self::SOUTH_WEST,
];

/// Create a direction from a finite, nonzero [`Vec2`], normalizing it.
///
/// Returns [`Err(InvalidDirectionError)`](InvalidDirectionError) if the length
Expand Down Expand Up @@ -395,6 +416,143 @@ impl Dir3 {
pub const NEG_Z: Self = Self(Vec3::NEG_Z);
/// The directional axes.
pub const AXES: [Self; 3] = [Self::X, Self::Y, Self::Z];
/// The cardinal directions.
pub const CARDINALS: [Self; 6] = [
Self::X,
Self::NEG_X,
Self::Y,
Self::NEG_Y,
Self::Z,
Self::NEG_Z,
];

// Adding this allow here to make sure that the precision in FRAC_1_SQRT_2
// and here is the same
#[expect(
clippy::excessive_precision,
reason = "compatibility with the unstable rust definition"
)]
/// Approximation of 1/sqrt(3) needed for the diagonals in 3D space
const FRAC_1_SQRT_3: f32 = 0.577350269189625764509148780501957456_f32;
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This seems a bit weird, since an f32 can't hold more than about 7 digits of precision, but I don't know if there's maybe another reason to want an extra-precise constant definition.

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these excessively long definitions are copied from the rust std::f32::consts, but I'm unsure why they would be there in the first place

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i propose to keep this definition for now for the sake of consistency with the rust stdlib, so that when the FRAC_1_SQRT_3 gets stabilized we can just switch over to that and be certain that there's no weird behavior from unexpected changes

/// The directions pointing towards the vertices of a cube centered at the origin.
pub const ALL_VERTICES: [Self; 8] = [
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
];
/// The directions towards centers of each edge of a cube
pub const ALL_EDGES: [Self; 12] = [
Self(Vec3::new(FRAC_1_SQRT_2, FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(-FRAC_1_SQRT_2, FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(FRAC_1_SQRT_2, -FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(-FRAC_1_SQRT_2, -FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(FRAC_1_SQRT_2, 0., FRAC_1_SQRT_2)),
Self(Vec3::new(-FRAC_1_SQRT_2, 0., FRAC_1_SQRT_2)),
Self(Vec3::new(FRAC_1_SQRT_2, 0., -FRAC_1_SQRT_2)),
Self(Vec3::new(-FRAC_1_SQRT_2, 0., -FRAC_1_SQRT_2)),
Self(Vec3::new(0., FRAC_1_SQRT_2, FRAC_1_SQRT_2)),
Self(Vec3::new(0., -FRAC_1_SQRT_2, FRAC_1_SQRT_2)),
Self(Vec3::new(0., FRAC_1_SQRT_2, -FRAC_1_SQRT_2)),
Self(Vec3::new(0., -FRAC_1_SQRT_2, -FRAC_1_SQRT_2)),
];
/// All neighbors of a tile on a cube grid a 3x3x3 neighborhood. A combination of [`Self::CARDINALS`], [`Self::ALL_EDGES`] and [`Self::ALL_VERTICES`]
pub const ALL_NEIGHBORS: [Self; 26] = [
Self::X,
Self::NEG_X,
Self::Y,
Self::NEG_Y,
Self::Z,
Self::NEG_Z,
Self(Vec3::new(FRAC_1_SQRT_2, FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(-FRAC_1_SQRT_2, FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(FRAC_1_SQRT_2, -FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(-FRAC_1_SQRT_2, -FRAC_1_SQRT_2, 0.)),
Self(Vec3::new(FRAC_1_SQRT_2, 0., FRAC_1_SQRT_2)),
Self(Vec3::new(-FRAC_1_SQRT_2, 0., FRAC_1_SQRT_2)),
Self(Vec3::new(FRAC_1_SQRT_2, 0., -FRAC_1_SQRT_2)),
Self(Vec3::new(-FRAC_1_SQRT_2, 0., -FRAC_1_SQRT_2)),
Self(Vec3::new(0., FRAC_1_SQRT_2, FRAC_1_SQRT_2)),
Self(Vec3::new(0., -FRAC_1_SQRT_2, FRAC_1_SQRT_2)),
Self(Vec3::new(0., FRAC_1_SQRT_2, -FRAC_1_SQRT_2)),
Self(Vec3::new(0., -FRAC_1_SQRT_2, -FRAC_1_SQRT_2)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
Self(Vec3::new(
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
-Self::FRAC_1_SQRT_3,
)),
];

/// Create a direction from a finite, nonzero [`Vec3`], normalizing it.
///
Expand Down