Removed full Jakob implementation and moved table loading to build time.

The "light" version of Jakob still remains, which uses a much smaller
table.
This commit is contained in:
Nathan Vegdahl 2019-06-21 21:45:13 +09:00
parent 5eeaec0a8b
commit 50f09a6134
8 changed files with 301 additions and 314 deletions

1
Cargo.lock generated
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@ -444,7 +444,6 @@ name = "spectral_upsampling"
version = "0.1.0"
dependencies = [
"float4 0.1.0",
"lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]

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@ -4,7 +4,7 @@ pub use color::{xyz_to_aces_ap0, xyz_to_aces_ap0_e, rec709_e_to_xyz, rec709_to_x
use float4::Float4;
use spectral_upsampling::{
meng::{spectrum_xyz_to_p_4, EQUAL_ENERGY_REFLECTANCE},
jakob::{spectrum_acesrgb_to_p4, small_spectrum_acesrgb_to_p4},
// jakob::{aces_to_spectrum_p4},
};
use crate::{lerp::Lerp, math::fast_exp};
@ -492,7 +492,7 @@ impl DivAssign<f32> for XYZ {
#[inline(always)]
fn xyz_to_spectrum_4(xyz: (f32, f32, f32), wavelengths: Float4) -> Float4 {
spectrum_xyz_to_p_4(wavelengths, xyz) * Float4::splat(1.0 / EQUAL_ENERGY_REFLECTANCE)
// small_spectrum_acesrgb_to_p4(wavelengths, xyz_to_aces_ap0_e(xyz))
// aces_to_spectrum_p4(wavelengths, xyz_to_aces_ap0_e(xyz))
}
/// Close analytic approximations of the CIE 1931 XYZ color curves.

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@ -9,9 +9,6 @@ license = "MIT"
name = "spectral_upsampling"
path = "src/lib.rs"
[dependencies]
lazy_static = "1.0"
# Local crate dependencies
[dependencies.float4]
path = "../float4"

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@ -0,0 +1,222 @@
// Get Jakob tables into a native rust format.
use std::{
env,
fs::File,
io::{self, Read, Write},
path::Path,
};
/// How many polynomial coefficients?
const RGB2SPEC_N_COEFFS: usize = 3;
/// Table resolution.
const TABLE_RES: usize = 64;
// For the small table, what is the middle value used?
const MID_VALUE: f32 = 0.5;
fn main() {
// Write tables to Rust file
let out_dir = env::var("OUT_DIR").unwrap();
let dest_path = Path::new(&out_dir).join("jakob_table_inc.rs");
let mut f = File::create(&dest_path).unwrap();
// Rec.709
let rec709_table = rgb2spec_load_small("jakob_tables/srgb.coeff");
f.write_all(format!("\nconst REC709_TABLE_RES: usize = {};", TABLE_RES).as_bytes())
.unwrap();
f.write_all(format!("\nconst REC709_TABLE_MID_VALUE: f32 = {};", MID_VALUE).as_bytes())
.unwrap();
f.write_all("\npub static REC709_TABLE: &[[(f32, f32, f32); 2]; 64 * 64 * 3] = &[".as_bytes())
.unwrap();
for item in &rec709_table {
f.write_all(
format!(
"\n [({}, {}, {}), ({}, {}, {})],",
item[0].0, item[0].1, item[0].2, item[1].0, item[1].1, item[1].2
)
.as_bytes(),
)
.unwrap();
}
f.write_all("\n];".as_bytes()).unwrap();
// Rec.2020
let rec2020_table = rgb2spec_load_small("jakob_tables/rec2020.coeff");
f.write_all(format!("\nconst REC2020_TABLE_RES: usize = {};", TABLE_RES).as_bytes())
.unwrap();
f.write_all(format!("\nconst REC2020_TABLE_MID_VALUE: f32 = {};", MID_VALUE).as_bytes())
.unwrap();
f.write_all("\npub static REC2020_TABLE: &[[(f32, f32, f32); 2]; 64 * 64 * 3] = &[".as_bytes())
.unwrap();
for item in &rec2020_table {
f.write_all(
format!(
"\n [({}, {}, {}), ({}, {}, {})],",
item[0].0, item[0].1, item[0].2, item[1].0, item[1].1, item[1].2
)
.as_bytes(),
)
.unwrap();
}
f.write_all("\n];".as_bytes()).unwrap();
// sRGB / ACES
let aces_table = rgb2spec_load_small("jakob_tables/aces2065_1.coeff");
f.write_all(format!("\nconst ACES_TABLE_RES: usize = {};", TABLE_RES).as_bytes())
.unwrap();
f.write_all(format!("\nconst ACES_TABLE_MID_VALUE: f32 = {};", MID_VALUE).as_bytes())
.unwrap();
f.write_all("\npub static ACES_TABLE: &[[(f32, f32, f32); 2]; 64 * 64 * 3] = &[".as_bytes())
.unwrap();
for item in &aces_table {
f.write_all(
format!(
"\n [({}, {}, {}), ({}, {}, {})],",
item[0].0, item[0].1, item[0].2, item[1].0, item[1].1, item[1].2
)
.as_bytes(),
)
.unwrap();
}
f.write_all("\n];".as_bytes()).unwrap();
}
/// Underlying representation
pub struct RGB2Spec {
res: usize,
scale: Vec<f32>,
data: Vec<[f32; RGB2SPEC_N_COEFFS]>,
}
pub fn rgb2spec_load(filepath: &str) -> RGB2Spec {
let file_contents = {
let mut file_contents = Vec::new();
let mut f = io::BufReader::new(File::open(filepath).unwrap());
f.read_to_end(&mut file_contents).unwrap();
file_contents
};
// Check the header
let header = &file_contents[0..4];
if header != "SPEC".as_bytes() {
panic!("Not a spectral table.");
}
// Get resolution of the table
let res = u32::from_le_bytes([
file_contents[4],
file_contents[5],
file_contents[6],
file_contents[7],
]) as usize;
// Calculate sizes
let size_scale = res;
let size_data = res * res * res * RGB2SPEC_N_COEFFS;
// Load the table scale data
let mut scale = Vec::with_capacity(size_scale);
for i in 0..size_scale {
let ii = i * 4 + 8;
let n = f32::from_bits(u32::from_le_bytes([
file_contents[ii],
file_contents[ii + 1],
file_contents[ii + 2],
file_contents[ii + 3],
]));
scale.push(n);
}
// Load the table coefficient data
let mut data = Vec::with_capacity(size_data);
for i in 0..size_data {
let ii = i * 4 * RGB2SPEC_N_COEFFS + 8 + (size_scale * 4);
let n1 = f32::from_bits(u32::from_le_bytes([
file_contents[ii],
file_contents[ii + 1],
file_contents[ii + 2],
file_contents[ii + 3],
]));
let n2 = f32::from_bits(u32::from_le_bytes([
file_contents[ii + 4],
file_contents[ii + 5],
file_contents[ii + 6],
file_contents[ii + 7],
]));
let n3 = f32::from_bits(u32::from_le_bytes([
file_contents[ii + 8],
file_contents[ii + 9],
file_contents[ii + 10],
file_contents[ii + 11],
]));
data.push([n1, n2, n3]);
}
RGB2Spec {
res: res,
scale: scale,
data: data,
}
}
pub fn rgb2spec_load_small(filepath: &str) -> Vec<[(f32, f32, f32); 2]> {
let big_table = rgb2spec_load(filepath);
assert!(big_table.res == TABLE_RES);
// Calculate z offsets and such for the mid value.
let dz: usize = 1 * big_table.res * big_table.res;
let z05_i = rgb2spec_find_interval(&big_table.scale, MID_VALUE);
let z05_1: f32 = (MID_VALUE - big_table.scale[z05_i])
/ (big_table.scale[z05_i + 1] - big_table.scale[z05_i]);
let z05_0: f32 = 1.0 - z05_1;
// Fill in table.
let mut table = vec![[(0.0, 0.0, 0.0); 2]; TABLE_RES * TABLE_RES * 3];
for i in 0..3 {
let offset = i * big_table.res * big_table.res * big_table.res;
for j in 0..(big_table.res * big_table.res) {
let one_coef = big_table.data[offset + ((TABLE_RES - 1) * dz) + j];
let mid_coef_0 = big_table.data[offset + (z05_i * dz) + j];
let mid_coef_1 = big_table.data[offset + ((z05_i + 1) * dz) + j];
let mid_coef = [
(mid_coef_0[0] * z05_0) + (mid_coef_1[0] * z05_1),
(mid_coef_0[1] * z05_0) + (mid_coef_1[1] * z05_1),
(mid_coef_0[2] * z05_0) + (mid_coef_1[2] * z05_1),
];
table[(i * big_table.res * big_table.res) + j] = [
(mid_coef[0], mid_coef[1], mid_coef[2]),
(one_coef[0], one_coef[1], one_coef[2]),
];
}
}
table
}
fn rgb2spec_find_interval(values: &[f32], x: f32) -> usize {
let last_interval = values.len() - 2;
let mut left = 0;
let mut size = last_interval;
while size > 0 {
let half = size >> 1;
let middle = left + half + 1;
if values[middle] < x {
left = middle;
size -= half + 1;
} else {
size = half;
}
}
if left < last_interval {
left
} else {
last_interval
}
}

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@ -1,74 +1,63 @@
use std::{fs::File, io, io::Read};
/// This file implements a lighter alternative version of the Jakob
/// 2019 spectral upsampling method. Instead of using the entire 3D
/// looking table, we use two 2d slices of the table and interpolate
/// between the evaluated spectral values calculated from those tables.
///
/// The provides similar color matching as full Jakob, at the expense of
/// somewhat lower quality spectrums, and the inability to precalculate
/// the coefficents for even more efficient evaluation later on.
use float4::Float4;
use lazy_static::lazy_static;
/// How many polynomial coefficients?
const RGB2SPEC_N_COEFFS: usize = 3;
/// Table resolution.
const TABLE_RES: usize = 64;
// Include tables generated by the build.rs script
include!(concat!(env!("OUT_DIR"), "/jakob_table_inc.rs"));
// For the small table, what is the middle value used?
const MID_VALUE: f32 = 0.5;
lazy_static! {
static ref ACES_TABLE: RGB2Spec = rgb2spec_load("");
static ref ACES_TABLE_SMALL: Vec<[Float4; 2]> = rgb2spec_load_small("");
}
pub fn spectrum_acesrgb_to_p(lambda: f32, rgb: (f32, f32, f32)) -> f32 {
let max = {
let mut max = rgb.0;
if max < rgb.1 {
max = rgb.1
};
if max < rgb.2 {
max = rgb.2
};
max
};
if max == 0.0 {
0.0
} else if max <= 1.0 {
let co = rgb2spec_fetch(&ACES_TABLE, [rgb.0, rgb.1, rgb.2]);
rgb2spec_eval(co, lambda)
} else {
let rgb = (rgb.0 / max, rgb.1 / max, rgb.2 / max);
let co = rgb2spec_fetch(&ACES_TABLE, [rgb.0, rgb.1, rgb.2]);
rgb2spec_eval(co, lambda) * max
}
#[inline]
pub fn rec709_to_spectrum_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Float4 {
small_rgb_to_spectrum_p4(
REC709_TABLE,
REC709_TABLE_RES,
REC709_TABLE_MID_VALUE,
lambdas,
rgb,
)
}
#[inline]
pub fn spectrum_acesrgb_to_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Float4 {
let max = {
let mut max = rgb.0;
if max < rgb.1 {
max = rgb.1
};
if max < rgb.2 {
max = rgb.2
};
max
};
if max == 0.0 {
Float4::splat(0.0)
} else if max <= 1.0 {
let co = rgb2spec_fetch(&ACES_TABLE, [rgb.0, rgb.1, rgb.2]);
rgb2spec_eval_4(co, lambdas)
} else {
let rgb_norm = (rgb.0 / max, rgb.1 / max, rgb.2 / max);
let co = rgb2spec_fetch(&ACES_TABLE, [rgb_norm.0, rgb_norm.1, rgb_norm.2]);
rgb2spec_eval_4(co, lambdas) * Float4::splat(max)
}
pub fn rec2020_to_spectrum_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Float4 {
small_rgb_to_spectrum_p4(
REC2020_TABLE,
REC2020_TABLE_RES,
REC2020_TABLE_MID_VALUE,
lambdas,
rgb,
)
}
#[inline]
pub fn small_spectrum_acesrgb_to_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Float4 {
pub fn aces_to_spectrum_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Float4 {
small_rgb_to_spectrum_p4(
ACES_TABLE,
ACES_TABLE_RES,
ACES_TABLE_MID_VALUE,
lambdas,
rgb,
)
}
//===============================================================
// Core functions, specialized above for specific color spaces.
#[inline(always)]
fn small_rgb_to_spectrum_p4(
table: &[[(f32, f32, f32); 2]],
table_res: usize,
table_mid_value: f32,
lambdas: Float4,
rgb: (f32, f32, f32),
) -> Float4 {
// Determine largest RGB component, and calculate the other two
// components scaled for lookups.
let (i, max_val, x, y) = {
@ -104,17 +93,35 @@ pub fn small_spectrum_acesrgb_to_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Fl
}
// Calculate lookup coordinates.
let xi = (x as usize).min(TABLE_RES - 2);
let yi = (y as usize).min(TABLE_RES - 2);
let offset = (TABLE_RES * TABLE_RES * i) + (yi * TABLE_RES) + xi;
let xi = (x as usize).min(table_res - 2);
let yi = (y as usize).min(table_res - 2);
let offset = (table_res * table_res * i) + (yi * table_res) + xi;
let dx = 1;
let dy = TABLE_RES;
let dy = table_res;
// Look up values from table.
let a0 = ACES_TABLE_SMALL[offset];
let a1 = ACES_TABLE_SMALL[offset + dx];
let a2 = ACES_TABLE_SMALL[offset + dy];
let a3 = ACES_TABLE_SMALL[offset + dy + dx];
let a0 = table[offset];
let a1 = table[offset + dx];
let a2 = table[offset + dy];
let a3 = table[offset + dy + dx];
// Convert to SIMD format for faster interpolation.
let a0 = [
Float4::new(a0[0].0, a0[0].1, a0[0].2, 0.0),
Float4::new(a0[1].0, a0[1].1, a0[1].2, 0.0),
];
let a1 = [
Float4::new(a1[0].0, a1[0].1, a1[0].2, 0.0),
Float4::new(a1[1].0, a1[1].1, a1[1].2, 0.0),
];
let a2 = [
Float4::new(a2[0].0, a2[0].1, a2[0].2, 0.0),
Float4::new(a2[1].0, a2[1].1, a2[1].2, 0.0),
];
let a3 = [
Float4::new(a3[0].0, a3[0].1, a3[0].2, 0.0),
Float4::new(a3[1].0, a3[1].1, a3[1].2, 0.0),
];
// Do interpolation.
let x1: f32 = x - xi as f32;
@ -126,12 +133,12 @@ pub fn small_spectrum_acesrgb_to_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Fl
let c = [(b0[0] * y0) + (b1[0] * y1), (b0[1] * y0) + (b1[1] * y1)];
// Evaluate the spectral function and return the result.
if max_val <= MID_VALUE {
if max_val <= table_mid_value {
rgb2spec_eval_4([c[0].get_0(), c[0].get_1(), c[0].get_2()], lambdas)
* (1.0 / MID_VALUE)
* (1.0 / table_mid_value)
* max_val
} else if max_val < 1.0 {
let n = (max_val - MID_VALUE) / (1.0 - MID_VALUE);
let n = (max_val - table_mid_value) / (1.0 - table_mid_value);
let s0 = rgb2spec_eval_4([c[0].get_0(), c[0].get_1(), c[0].get_2()], lambdas);
let s1 = rgb2spec_eval_4([c[1].get_0(), c[1].get_1(), c[1].get_2()], lambdas);
(s0 * (1.0 - n)) + (s1 * n)
@ -140,141 +147,14 @@ pub fn small_spectrum_acesrgb_to_p4(lambdas: Float4, rgb: (f32, f32, f32)) -> Fl
}
}
pub fn rgb2spec_load(filepath: &str) -> RGB2Spec {
let file_contents = {
let mut file_contents = Vec::new();
let mut f = io::BufReader::new(File::open(filepath).unwrap());
f.read_to_end(&mut file_contents).unwrap();
file_contents
};
// Check the header
let header = &file_contents[0..4];
if header != "SPEC".as_bytes() {
panic!("Not a spectral table.");
}
// Get resolution of the table
let res = u32::from_le_bytes([
file_contents[4],
file_contents[5],
file_contents[6],
file_contents[7],
]) as usize;
// Calculate sizes
let size_scale = res;
let size_data = res * res * res * RGB2SPEC_N_COEFFS;
// Load the table scale data
let mut scale = Vec::with_capacity(size_scale);
for i in 0..size_scale {
let ii = i * 4 + 8;
let n = f32::from_bits(u32::from_le_bytes([
file_contents[ii],
file_contents[ii + 1],
file_contents[ii + 2],
file_contents[ii + 3],
]));
scale.push(n);
}
// Load the table coefficient data
let mut data = Vec::with_capacity(size_data);
for i in 0..size_data {
let ii = i * 4 * RGB2SPEC_N_COEFFS + 8 + (size_scale * 4);
let n1 = f32::from_bits(u32::from_le_bytes([
file_contents[ii],
file_contents[ii + 1],
file_contents[ii + 2],
file_contents[ii + 3],
]));
let n2 = f32::from_bits(u32::from_le_bytes([
file_contents[ii + 4],
file_contents[ii + 5],
file_contents[ii + 6],
file_contents[ii + 7],
]));
let n3 = f32::from_bits(u32::from_le_bytes([
file_contents[ii + 8],
file_contents[ii + 9],
file_contents[ii + 10],
file_contents[ii + 11],
]));
data.push([n1, n2, n3]);
}
RGB2Spec {
res: res,
scale: scale,
data: data,
}
}
pub fn rgb2spec_load_small(filepath: &str) -> Vec<[Float4; 2]> {
let big_table = rgb2spec_load(filepath);
assert!(big_table.res == TABLE_RES);
// Calculate z offsets and such for the mid value.
let dz: usize = 1 * big_table.res * big_table.res;
let z05_i = rgb2spec_find_interval(&big_table.scale, MID_VALUE);
let z05_1: f32 = (MID_VALUE - big_table.scale[z05_i])
/ (big_table.scale[z05_i + 1] - big_table.scale[z05_i]);
let z05_0: f32 = 1.0 - z05_1;
// Fill in table.
let mut table = vec![[Float4::splat(0.0); 2]; TABLE_RES * TABLE_RES * 3];
for i in 0..3 {
let offset = i * big_table.res * big_table.res * big_table.res;
for j in 0..(big_table.res * big_table.res) {
let one_coef = big_table.data[offset + ((TABLE_RES - 1) * dz) + j];
let mid_coef_0 = big_table.data[offset + (z05_i * dz) + j];
let mid_coef_1 = big_table.data[offset + ((z05_i + 1) * dz) + j];
let mid_coef = [
(mid_coef_0[0] * z05_0) + (mid_coef_1[0] * z05_1),
(mid_coef_0[1] * z05_0) + (mid_coef_1[1] * z05_1),
(mid_coef_0[2] * z05_0) + (mid_coef_1[2] * z05_1),
];
table[(i * big_table.res * big_table.res) + j] = [
Float4::new(mid_coef[0], mid_coef[1], mid_coef[2], 0.0),
Float4::new(one_coef[0], one_coef[1], one_coef[2], 0.0),
];
}
}
table
}
/// Underlying representation
pub struct RGB2Spec {
res: usize,
scale: Vec<f32>,
data: Vec<[f32; RGB2SPEC_N_COEFFS]>,
}
//============================================================
// Coefficient -> eval functions
#[inline(always)]
fn rgb2spec_fma(a: f32, b: f32, c: f32) -> f32 {
a * b + c
}
#[inline(always)]
fn rgb2spec_fma_4(a: Float4, b: Float4, c: Float4) -> Float4 {
a.fmadd(b, c)
}
fn rgb2spec_eval(coeff: [f32; RGB2SPEC_N_COEFFS], lambda: f32) -> f32 {
let x = rgb2spec_fma(rgb2spec_fma(coeff[0], lambda, coeff[1]), lambda, coeff[2]);
let y = 1.0 / (rgb2spec_fma(x, x, 1.0)).sqrt();
rgb2spec_fma(0.5 * x, y, 0.5)
}
fn rgb2spec_eval_4(coeff: [f32; RGB2SPEC_N_COEFFS], lambda: Float4) -> Float4 {
let co0 = Float4::splat(coeff[0]);
let co1 = Float4::splat(coeff[1]);
@ -286,114 +166,3 @@ fn rgb2spec_eval_4(coeff: [f32; RGB2SPEC_N_COEFFS], lambda: Float4) -> Float4 {
rgb2spec_fma_4(Float4::splat(0.5) * x, y, Float4::splat(0.5))
}
//=================================================================
// Other misc helper functions
fn rgb2spec_find_interval(values: &[f32], x: f32) -> usize {
let last_interval = values.len() - 2;
let mut left = 0;
let mut size = last_interval;
while size > 0 {
let half = size >> 1;
let middle = left + half + 1;
if values[middle] < x {
left = middle;
size -= half + 1;
} else {
size = half;
}
}
if left < last_interval {
left
} else {
last_interval
}
}
/// Convert an RGB value into a RGB2Spec coefficient representation
fn rgb2spec_fetch(model: &RGB2Spec, rgb: [f32; 3]) -> [f32; RGB2SPEC_N_COEFFS] {
assert!(
rgb[0] >= 0.0
&& rgb[1] >= 0.0
&& rgb[2] >= 0.0
&& rgb[0] <= 1.0
&& rgb[1] <= 1.0
&& rgb[2] <= 1.0
);
let res = model.res;
// Determine largest RGB component.
let i = {
let mut i = 0;
if rgb[i] < rgb[1] {
i = 1;
}
if rgb[i] < rgb[2] {
i = 2;
}
i
};
let z = rgb[i];
let scale = (res - 1) as f32 / z;
let x = rgb[(i + 1) % 3] * scale;
let y = rgb[(i + 2) % 3] * scale;
// Bilinearly interpolated lookup.
let xi: usize = if (x as usize) < (res - 2) {
x as usize
} else {
res - 2
};
let yi: usize = if (y as usize) < (res - 2) {
y as usize
} else {
res - 2
};
let zi: usize = rgb2spec_find_interval(&model.scale, z);
let offset: usize = ((i * res + zi) * res + yi) * res + xi;
let dx: usize = 1;
let dy: usize = 1 * res;
let dz: usize = 1 * res * res;
let x1: f32 = x - xi as f32;
let x0: f32 = 1.0 - x1 as f32;
let y1: f32 = y - yi as f32;
let y0: f32 = 1.0 - y1 as f32;
let z1: f32 = (z - model.scale[zi]) / (model.scale[zi + 1] - model.scale[zi]);
let z0: f32 = 1.0 - z1 as f32;
let a0 = model.data[offset];
let a0 = Float4::new(a0[0], a0[1], a0[2], 0.0);
let a1 = model.data[offset + dx];
let a1 = Float4::new(a1[0], a1[1], a1[2], 0.0);
let a2 = model.data[offset + dy];
let a2 = Float4::new(a2[0], a2[1], a2[2], 0.0);
let a3 = model.data[offset + dy + dx];
let a3 = Float4::new(a3[0], a3[1], a3[2], 0.0);
let a4 = model.data[offset + dz];
let a4 = Float4::new(a4[0], a4[1], a4[2], 0.0);
let a5 = model.data[offset + dz + dx];
let a5 = Float4::new(a5[0], a5[1], a5[2], 0.0);
let a6 = model.data[offset + dz + dy];
let a6 = Float4::new(a6[0], a6[1], a6[2], 0.0);
let a7 = model.data[offset + dz + dy + dx];
let a7 = Float4::new(a7[0], a7[1], a7[2], 0.0);
let b0 = (a0 * x0) + (a1 * x1);
let b1 = (a2 * x0) + (a3 * x1);
let b2 = (a4 * x0) + (a5 * x1);
let b3 = (a6 * x0) + (a7 * x1);
let c0 = (b0 * y0) + (b1 * y1);
let c1 = (b2 * y0) + (b3 * y1);
let d = (c0 * z0) + (c1 * z1);
[d.get_0(), d.get_1(), d.get_2()]
}