nx_aces_native.nx

nx_aces_native.nx -- scene-referred linear color transforms, rewritten bits-up in NishiLang. No external library, no OSI license inherited. Numerical constants only -- the matrix values are PUBLISHED MATH from SMPTE / CIE standards work, not any one organisation's intellectual property. Per cardinal `feedback-dont-rebuild-commodity-platform-layers`: the sRGB OETF and the Rec.709-to-ACEScg-style working-space matrices are public standards (CIE 15:2004, IEC 61966-2-1, SMPTE ST 2065-1) -- we derive them from first principles + ship our own NishiLang implementation. The substrate's color pipeline is therefore Nishi-stack from bits up. Three primitives: nx_aces_srgb_to_linear_q14 -- piecewise sRGB OETF inverse nx_aces_linear_to_srgb_q14 -- piecewise sRGB OETF forward nx_aces_linear_to_workingspace -- 3x3 matrix mul to a wide scene-linear working primary set (substrate's own primaries; dimensionally compatible with ACEScg but our own values). Q14 fixed-point throughout (16384 unit) so we have headroom for HDR values > 1.0 without losing the low-end. All math is i64 integer + bit-shift, no float ops. Substrate's "no FPU dep" discipline. IMPORTANT: caller is responsible for pixel-shape consistency. This primitive operates on a single (r, g, b) triple at a time. Composes with future nx_image_pixel_map for bulk image transform. genealogy_id: substrate_native_color_transform_2026_05_16 lineage_id: nishi_family_custom_license_color_v1