feat: spherindrical harmonics scaffold

src/material/mod.rs

@@ -2,6 +2,7 @@ use bevy::prelude::*;
 
 pub mod depth;
 pub mod spherical_harmonics;
+pub mod spherindrical_harmonics;
 
 #[cfg(feature = "material_noise")]
 pub mod noise;

src/material/spherindrical_harmonics.rs

@@ -0,0 +1,45 @@
+use std::marker::Copy;
+
+use bevy::{
+    prelude::*,
+    asset::load_internal_asset,
+    render::render_resource::ShaderType,
+};
+use bytemuck::{
+    Pod,
+    Zeroable,
+};
+use serde::{
+    Deserialize,
+    Serialize,
+    Serializer,
+    ser::SerializeTuple,
+};
+
+#[cfg(feature = "f16")]
+use half::f16;
+
+use crate::material::spherical_harmonics::{
+
+};
+
+
+#[cfg(feature = "f16")]
+#[derive(
+    Clone,
+    Copy,
+    Debug,
+    PartialEq,
+    Reflect,
+    ShaderType,
+    Pod,
+    Zeroable,
+    Serialize,
+    Deserialize,
+)]
+#[repr(C)]
+pub struct SpherindricalHarmonicCoefficients {
+    #[reflect(ignore)]
+    #[serde(serialize_with = "coefficients_serializer", deserialize_with = "coefficients_deserializer")]
+    pub coefficients: [u32; HALF_SH_COEFF_COUNT],
+}

src/material/spherindrical_harmonics.wgsl

@@ -0,0 +1,54 @@
+#define_import_path bevy_gaussian_splatting::spherindrical_harmonics
+#import bevy_gaussian_splatting::bindings::globals
+#import bevy_gaussian_splatting::spherical_harmonics::{
+    shc,
+    spherical_harmonics_lookup,
+}
+
+
+fn spherindrical_harmonics_lookup(
+    ray_direction: vec3<f32>,
+    sh: array<f32, #{SH_COEFF_COUNT}>,
+) -> vec3<f32> {
+    let rds = ray_direction * ray_direction;
+    let dir_t = globals.time;
+
+    var color = vec3<f32>(0.5);
+
+    color += shc[ 0] * vec3<f32>(sh[0], sh[1], sh[2]);
+
+#if SH_DEG > 0
+    color += shc[ 1] * vec3<f32>(sh[ 3], sh[ 4], sh[ 5]) * ray_direction.y;
+    color += shc[ 2] * vec3<f32>(sh[ 6], sh[ 7], sh[ 8]) * ray_direction.z;
+    color += shc[ 3] * vec3<f32>(sh[ 9], sh[10], sh[11]) * ray_direction.x;
+#endif
+
+#if SH_DEG > 1
+    color += shc[ 4] * vec3<f32>(sh[12], sh[13], sh[14]) * ray_direction.x * ray_direction.y;
+    color += shc[ 5] * vec3<f32>(sh[15], sh[16], sh[17]) * ray_direction.y * ray_direction.z;
+    color += shc[ 6] * vec3<f32>(sh[18], sh[19], sh[20]) * (2.0 * rds.z - rds.x - rds.y);
+    color += shc[ 7] * vec3<f32>(sh[21], sh[22], sh[23]) * ray_direction.x * ray_direction.z;
+    color += shc[ 8] * vec3<f32>(sh[24], sh[25], sh[26]) * (rds.x - rds.y);
+#endif
+
+#if SH_DEG > 2
+    color += shc[ 9] * vec3<f32>(sh[27], sh[28], sh[29]) * ray_direction.y * (3.0 * rds.x - rds.y);
+    color += shc[10] * vec3<f32>(sh[30], sh[31], sh[32]) * ray_direction.x * ray_direction.y * ray_direction.z;
+    color += shc[11] * vec3<f32>(sh[33], sh[34], sh[35]) * ray_direction.y * (4.0 * rds.z - rds.x - rds.y);
+    color += shc[12] * vec3<f32>(sh[36], sh[37], sh[38]) * ray_direction.z * (2.0 * rds.z - 3.0 * rds.x - 3.0 * rds.y);
+    color += shc[13] * vec3<f32>(sh[39], sh[40], sh[41]) * ray_direction.x * (4.0 * rds.z - rds.x - rds.y);
+    color += shc[14] * vec3<f32>(sh[42], sh[43], sh[44]) * ray_direction.z * (rds.x - rds.y);
+    color += shc[15] * vec3<f32>(sh[45], sh[46], sh[47]) * ray_direction.x * (rds.x - 3.0 * rds.y);
+#endif
+
+// TODO: add SH_DEG and SH_DEG_T shader defines
+#if SH_DEG_T > 0
+
+#endif
+
+#if SH_DEG_T > 1
+
+#endif
+
+    return color;
+}