release/0.11.0

[mxfactorial]

0.11.0 (2026-03-20)

breaking

• Angle internal representation changed from radians to stereographic projection ratio t = tan(θ/2)
• rem() now derived from t via 2.0 * t.atan() — values match within f64 precision but are no longer stored directly
• normalize_boundaries() removed — boundary logic is algebraic in the tangent sum formula
• Display for Angle now shows t instead of rem

added

• Angle::t() — projection ratio between adjacent π/2 blades
• Angle::from_parts(blade, t) — direct construction from blade and projection ratio
• Angle::cos_sin() — rational cos/sin: cos = (1-t²)/(1+t²), sin = 2t/(1+t²). no trig calls
• Angle::near(&other) — floating point comparison within tolerance
• Angle::near_rad(radians) — grade_angle comparison within tolerance
• Angle::near_rem(radians) — remainder comparison within tolerance
• Geonum::near(&other) — magnitude + angle comparison within tolerance
• Geonum::near_mag(value) — magnitude comparison within tolerance

changed

• Angle::new() converts π fractions to t internally — one tan() call at construction
• Angle::new_from_cartesian() uses t = opp/(hyp + adj) — one sqrt, no atan2
• Angle::geometric_add() uses tangent sum formula with rational boundary correction (T-1)/(T+1)
• Angle::geometric_sub() uses tangent difference formula with rational borrow (1-|R|)/(1+|R|)
• Angle::dual(), conjugate(), negate() simplified to blade arithmetic
• Angle::grade_angle() derives radians from t via atan()
• Angle::project() uses cos_sin() instead of grade_angle().cos()
• Geonum::dot(), wedge(), cos(), sin(), distance_to(), project_to_angle() use cos_sin()
• Geonum::geo() computes single cos_sin() for both dot and wedge
• Geonum addition uses rational projection pipeline: cos_sin (0 sqrts) → sum → magnitude (1 sqrt) → cartesian recovery (0 sqrts)

performance

operation	0.10.5	0.11.0	speedup
addition	68.8 ns	13.9 ns	5.0×
cos	11.6 ns	3.5 ns	3.3×
from_cartesian	24.4 ns	3.6 ns	6.7×
dot product	11.0 ns	8.6 ns	1.3×
wedge product	12.6 ns	10.3 ns	1.2×
geometric product	25.7 ns	18 ns	1.4×
projection	11.5 ns	8.6 ns	1.3×
distance	21.6 ns	17.6 ns	1.2×
differentiate	4.5 ns	3.4 ns	1.3×