Struct ShadowUniforms 

#[repr(C)]
pub struct ShadowUniforms {
    pub light_vps: [[[f32; 4]; 4]; 4],
    pub cascade_splits: [f32; 4],
    pub active_cascades: u32,
    pub _pad: [u32; 3],
}

Cascaded shadow map view-projection matrices and split depths.

Pushed to the shadow-pass vertex shader at buffer(0) (alongside a cascade_idx push constant that picks one matrix) and to the main-pass fragment shader at buffer(5). Layout must stay in sync with the ShadowUniforms struct in the single-source shaders. Three of them declare it: the forward pass stops at active_cascades, the shadow pass at cascade_splits, and only the fog froxel kernel spells out the trailing pad.

cascade_splits are the view-space depth thresholds (positive) marking the FAR end of each cascade. The fragment shader picks the first cascade whose split is greater than the fragment’s view-space depth. Slot 3 (the last cascade’s far end) doubles as the overall shadow distance.

Fields

light_vps: [[[f32; 4]; 4]; 4]

One light-space VP matrix per cascade, column-major.

cascade_splits: [f32; 4]

View-space depth at the FAR end of each cascade. Stored as a vec4 to keep MSL std140-like alignment trivial across backends. Slots [active_cascades..] hold a negative sentinel so the fragment shader’s split comparison never selects an unrendered cascade.

active_cascades: u32

How many of the NUM_SHADOW_CASCADES slots are live this frame (1..=4, from GraphicsConfig.shadow_cascades). The array capacity stays 4; only the first active_cascades are split, rendered, and sampled. The fragment shader bounds both its cascade fallback and its cross-cascade blend by this so it never reads a slot the CPU did not render.

_pad: [u32; 3]

Pads the struct to 288 bytes (a multiple of 16). The Rust [[f32; 4]; 4] matrices are only 4-byte aligned, so Rust would otherwise leave this at 276; the MSL float4x4-aligned struct and the GLSL std140 block both round up to 288, so the upload size must match for the bound buffer range to cover them.

Trait Implementations

impl Clone for ShadowUniforms

fn clone(&self) -> ShadowUniforms

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ShadowUniforms

impl NoUninit for ShadowUniforms