oxihuman_morph/
brow_lateral_control.rs

1// Copyright (C) 2026 COOLJAPAN OU (Team KitaSan) / SPDX-License-Identifier: Apache-2.0
2#![allow(dead_code)]
3
4//! Brow lateral-shift control — independent left/right horizontal brow translation.
5
6use std::f32::consts::PI;
7
8/// Configuration for brow lateral control.
9#[allow(dead_code)]
10#[derive(Debug, Clone, PartialEq)]
11pub struct BrowLateralConfig {
12    /// Maximum lateral offset in normalised units.
13    pub max_offset: f32,
14    /// Allow asymmetric shifts.
15    pub allow_asymmetry: bool,
16}
17
18impl Default for BrowLateralConfig {
19    fn default() -> Self {
20        Self {
21            max_offset: 0.04,
22            allow_asymmetry: true,
23        }
24    }
25}
26
27/// Lateral brow shift for one side.
28#[allow(dead_code)]
29#[derive(Debug, Clone, Copy, PartialEq, Eq)]
30pub enum BrowSide {
31    Left,
32    Right,
33}
34
35/// Runtime state.
36#[allow(dead_code)]
37#[derive(Debug, Clone, Default)]
38pub struct BrowLateralState {
39    /// Left brow horizontal shift, −1..=1.
40    pub left: f32,
41    /// Right brow horizontal shift, −1..=1.
42    pub right: f32,
43}
44
45/// Create new state.
46#[allow(dead_code)]
47pub fn new_brow_lateral_state() -> BrowLateralState {
48    BrowLateralState::default()
49}
50
51/// Default config.
52#[allow(dead_code)]
53pub fn default_brow_lateral_config() -> BrowLateralConfig {
54    BrowLateralConfig::default()
55}
56
57/// Set shift for one side.
58#[allow(dead_code)]
59pub fn blat_set(state: &mut BrowLateralState, side: BrowSide, v: f32) {
60    let v = v.clamp(-1.0, 1.0);
61    match side {
62        BrowSide::Left => state.left = v,
63        BrowSide::Right => state.right = v,
64    }
65}
66
67/// Set both sides to the same value.
68#[allow(dead_code)]
69pub fn blat_set_both(state: &mut BrowLateralState, v: f32) {
70    let v = v.clamp(-1.0, 1.0);
71    state.left = v;
72    state.right = v;
73}
74
75/// Reset to neutral.
76#[allow(dead_code)]
77pub fn blat_reset(state: &mut BrowLateralState) {
78    *state = BrowLateralState::default();
79}
80
81/// Whether effectively neutral.
82#[allow(dead_code)]
83pub fn blat_is_neutral(state: &BrowLateralState) -> bool {
84    state.left.abs() < 1e-4 && state.right.abs() < 1e-4
85}
86
87/// Asymmetry magnitude.
88#[allow(dead_code)]
89pub fn blat_asymmetry(state: &BrowLateralState) -> f32 {
90    (state.left - state.right).abs()
91}
92
93/// Average lateral value.
94#[allow(dead_code)]
95pub fn blat_average(state: &BrowLateralState) -> f32 {
96    (state.left + state.right) * 0.5
97}
98
99/// Convert to world-space offsets.
100#[allow(dead_code)]
101pub fn blat_to_weights(state: &BrowLateralState, cfg: &BrowLateralConfig) -> [f32; 2] {
102    [state.left * cfg.max_offset, state.right * cfg.max_offset]
103}
104
105/// Effective rotation angle in radians (approximation).
106#[allow(dead_code)]
107pub fn blat_rotation_rad(state: &BrowLateralState) -> f32 {
108    blat_average(state) * (PI / 12.0)
109}
110
111/// Blend two states.
112#[allow(dead_code)]
113pub fn blat_blend(a: &BrowLateralState, b: &BrowLateralState, t: f32) -> BrowLateralState {
114    let t = t.clamp(0.0, 1.0);
115    let inv = 1.0 - t;
116    BrowLateralState {
117        left: a.left * inv + b.left * t,
118        right: a.right * inv + b.right * t,
119    }
120}
121
122/// Serialise to JSON-like string.
123#[allow(dead_code)]
124pub fn blat_to_json(state: &BrowLateralState) -> String {
125    format!(
126        "{{\"left\":{:.4},\"right\":{:.4}}}",
127        state.left, state.right
128    )
129}
130
131#[cfg(test)]
132mod tests {
133    use super::*;
134
135    #[test]
136    fn default_is_neutral() {
137        assert!(blat_is_neutral(&new_brow_lateral_state()));
138    }
139
140    #[test]
141    fn set_clamps_high() {
142        let mut s = new_brow_lateral_state();
143        blat_set(&mut s, BrowSide::Left, 10.0);
144        assert!((s.left - 1.0).abs() < 1e-6);
145    }
146
147    #[test]
148    fn set_clamps_low() {
149        let mut s = new_brow_lateral_state();
150        blat_set(&mut s, BrowSide::Right, -10.0);
151        assert!((s.right + 1.0).abs() < 1e-6);
152    }
153
154    #[test]
155    fn set_both_equal() {
156        let mut s = new_brow_lateral_state();
157        blat_set_both(&mut s, 0.5);
158        assert!((s.left - s.right).abs() < 1e-6);
159    }
160
161    #[test]
162    fn reset_clears_values() {
163        let mut s = new_brow_lateral_state();
164        blat_set_both(&mut s, 0.7);
165        blat_reset(&mut s);
166        assert!(blat_is_neutral(&s));
167    }
168
169    #[test]
170    fn asymmetry_zero_when_equal() {
171        let mut s = new_brow_lateral_state();
172        blat_set_both(&mut s, 0.4);
173        assert!(blat_asymmetry(&s) < 1e-6);
174    }
175
176    #[test]
177    fn asymmetry_positive_when_different() {
178        let mut s = new_brow_lateral_state();
179        blat_set(&mut s, BrowSide::Left, 0.3);
180        blat_set(&mut s, BrowSide::Right, -0.3);
181        assert!(blat_asymmetry(&s) > 0.5);
182    }
183
184    #[test]
185    fn weights_scale_by_max_offset() {
186        let cfg = BrowLateralConfig {
187            max_offset: 0.1,
188            allow_asymmetry: true,
189        };
190        let mut s = new_brow_lateral_state();
191        blat_set_both(&mut s, 1.0);
192        let w = blat_to_weights(&s, &cfg);
193        assert!((w[0] - 0.1).abs() < 1e-6);
194    }
195
196    #[test]
197    fn blend_midpoint() {
198        let mut a = new_brow_lateral_state();
199        let mut b = new_brow_lateral_state();
200        blat_set_both(&mut a, 0.0);
201        blat_set_both(&mut b, 1.0);
202        let r = blat_blend(&a, &b, 0.5);
203        assert!((r.left - 0.5).abs() < 1e-5);
204    }
205
206    #[test]
207    fn json_has_keys() {
208        let s = new_brow_lateral_state();
209        let j = blat_to_json(&s);
210        assert!(j.contains("left") && j.contains("right"));
211    }
212}
oxihuman_morph/brow_lateral_control.rs

oxihuman_morph/
brow_lateral_control.rs
