Struct EvalCtx 

pub struct EvalCtx<'a> {
    pub scope_size: Vec3,
    pub split_i: f64,
    pub split_n: f64,
    pub depth: f64,
    pub params: &'a [(String, f64)],
    pub globals: &'a HashMap<String, f64>,
    pub rng: &'a mut Pcg64,
}

Per-shape evaluation context.

Built by the interpreter for each work item; params are the innermost rule-call arguments (linear scan, shadowing globals), globals the merged attribute/constant table (style and host overrides already applied).

Fields

scope_size: Vec3

Current scope extents (scope.x / scope.y / scope.z).

split_i: f64

Zero-based index within the last split/repeat; 0.0 at the root.

split_n: f64

Sibling count of the last split/repeat; 1.0 at the root.

depth: f64

Derivation depth of the current rule invocation.

params: &'a [(String, f64)]

Innermost rule-call parameter bindings; searched in reverse so the latest binding of a repeated name wins.

globals: &'a HashMap<String, f64>

Grammar attributes + constants (merged, overrides applied).

rng: &'a mut Pcg64

Per-shape RNG stream (rand(..) draws).