Struct ShapeGenotype 

pub struct ShapeGenotype {
    pub rules: HashMap<String, RuleDef>,
}

Genetic encoding of a CGA shape grammar.

Wraps the rule table of an Interpreter so that the grammar can be evolved by symbios-genetics algorithms. Parametric floats are mutated with Gaussian jitter; crossover uses homologous BLX-α blending on rules that share both name and op-sequence topology, or uniform crossover when topologies differ.

Fields

rules: HashMap<String, RuleDef>

Grammar rules: rule name → definition (declared parameters + variants). Parameter lists ride along unmutated so parameterized grammars round-trip through evolution intact.

Implementations

impl ShapeGenotype

pub fn from_interpreter(interp: &Interpreter) -> Self

Snapshot the rule table from a live interpreter.

pub fn to_interpreter(&self) -> Interpreter

Build a fresh Interpreter from this genotype.

Does not copy seed, max_depth, max_terminals, or host attributes — set those on the returned interpreter if your grammar requires non-default values.

Trait Implementations

impl Clone for ShapeGenotype

fn clone(&self) -> ShapeGenotype

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ShapeGenotype

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ShapeGenotype

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Genotype for ShapeGenotype

fn mutate<R: Rng>(&mut self, rng: &mut R, rate: f32)

Perturb parametric floats throughout the grammar.

Each mutable float is independently tested against rate. When selected, Gaussian noise (Box-Muller) is applied and the result is clamped to keep the grammar structurally valid:

Op	Parameter	σ	Clamp
Extrude(h)	h	0.5	> 0.1
Taper(t)	t	0.1	[0, 1]
Scale(v)	each component	0.2	> 0.1
Translate(v)	each component	0.5	none
Split slot sizes	size value	0.3	> 0.1 (or [0.01, 1] for Relative)
Repeat tile_size	tile_size	0.3	> 0.1
Roof angle	angle (°)	5.0	[1, 89]
Roof overhang	overhang	0.2	[0, 2]

After per-slot jitter, each Split is repaired so that its absolute and relative slot sums do not exceed their pre-mutation totals — this prevents independent jitter from producing SplitOverflow errors at interpret time (issue #27).

fn crossover<R: Rng>(&self, other: &Self, rng: &mut R) -> Self

Homologous BLX-α crossover (α = 0.5).

For each rule name shared by both parents:

• If both parents have the same number of variants and each variant pair has the same op-sequence topology (same variant discriminants in the same order), every float parameter is blended using BLX-α, producing offspring that explore slightly beyond the parental range.
• If the variant counts or topologies differ, the whole rule is inherited uniformly at random from one parent (50 / 50).

Rules present in only one parent are passed through to the child unchanged, so the child always has a complete, runnable grammar.

impl Serialize for ShapeGenotype

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.