Struct DdaEnv 

pub struct DdaEnv<'a> {
    pub sky: Option<&'a Sky>,
    pub fog_color: u32,
    pub fog_max_dist: f32,
    pub side_shades: [i8; 6],
    pub materials: Option<&'a MaterialTable>,
    pub terrain_materials: &'a [(Rgb, u8)],
    pub lights: CpuLights<'a>,
    pub world_shadow: Option<WorldShadowCtx<'a>>,
    pub z_clip: Option<i32>,
    pub cutout: Option<CpuCutout>,
    pub fow: Option<&'a dyn FowStyler>,
}

Per-frame environment for DDA shading (Substage DDA.5): a textured sky panorama, distance fog, and per-face side shading.

DdaEnv::default disables all three — flat baked-brightness hits and a caller-pre-filled solid sky — so the brickmap/dense equivalence tests run against an unchanged pipeline.

Fields

sky: Option<&'a Sky>

Textured sky sampled per-ray-direction on a miss. None leaves the destination untouched (caller’s solid sky pre-fill shows).

fog_color: u32

Fog target colour (0x__RRGGBB); hits blend toward it with distance. Typically the sky colour so terrain fades into the sky.

fog_max_dist: f32

Depth at which fog is fully opaque. <= 0 disables fog.

side_shades: [i8; 6]

Per-face brightness reduction [x-, x+, y-, y+, z-, z+], applied to the hit face (voxlap setsideshades). All-zero = off.

materials: Option<&'a MaterialTable>

TV: global voxel-material palette (id → opacity + blend mode). None keeps terrain fully opaque (the first-hit path, bit-identical).

terrain_materials: &'a [(Rgb, u8)]

TV: terrain colour→material map ((rgb, material_id)). A hit voxel’s colour is looked up here for its material. Empty (the default) ⇒ every voxel is opaque, so the march returns the first hit unchanged.

lights: CpuLights<'a>

CPU.1 — dynamic lighting (stage DL on the CPU): sun + point lights + stylized cel/ramp, evaluated flat per voxel. Disabled by default ⇒ the hit uses the baked-byte shade path, byte-identical to pre-DL. Lights here are already in the grid’s local frame (the scene renderer transforms them per grid). Shadows: see Self::world_shadow.

world_shadow: Option<WorldShadowCtx<'a>>

XS.1 — when set, shadow rays test the whole scene (all grids + sprites) via this world-space occluder + the current grid’s local→world transform, instead of the single-grid SamplerShadow. None ⇒ single-grid shadows (the direct render_dda path / tests).

z_clip: Option<i32>

CA.0 — per-grid cutaway clip (stage CA), grid-local absolute voxel z (the same space as GridView::voxel_bounds, spanning stacked chz chunks; z-down). Some(z) makes the renderer treat every cell with z < z_clip as air — the isometric “deck view” cut; z_clip itself is the first visible layer, whose top face renders as the cut surface (colour = the existing GridView::surface_color_mip run-top fallback). Render-only: simulation / collision / audio are untouched. None (the default) disables clipping — byte-identical to pre-CA renders.

cutout: Option<CpuCutout>

OC.0 — per-grid derived view cutout (stage OC): the screen-space “keyhole” through front walls for third-person play. Unlike Self::z_clip (grid state, “world as if removed”) this is transient per-frame VIEW state: primary rays only — shadow marches, occluders, collision and gameplay raycasts never see it. None (the default) is byte-identical to pre-OC renders.

fow: Option<&'a dyn FowStyler>

FW.2 — per-hit fog-of-war styling (stage FW). When set, each solid hit is classified by grid-local voxel into a FowVerdict: Hide cells read as air (the observer never saw them — the marcher continues, like Self::cutout); Show cells are dimmed / desaturated and may suppress the dynamic-light rig (memory renders the frozen BAKED look). Applied to the fog-of-war twin grid only (the scene renderer sets it per grid). None (the default) is byte-identical to pre-FW renders. See FowStyler.

Trait Implementations

impl<'a> Clone for DdaEnv<'a>

fn clone(&self) -> DdaEnv<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Copy for DdaEnv<'a>

impl Default for DdaEnv<'_>

fn default() -> Self

Returns the “default value” for a type.