fix physics bugs

2 files changed, 25 insertions, 0 deletions

diff --git a/azalea-core/src/lib.rs b/azalea-core/src/lib.rs
index 8ed62b06..6554d71d 100755
--- a/azalea-core/src/lib.rs
+++ b/azalea-core/src/lib.rs
@@ -1,6 +1,7 @@
 #![doc = include_str!("../README.md")]
 #![feature(int_roundings)]
 #![feature(const_for)]
+#![feature(lazy_cell)]
 #![allow(incomplete_features)]
 #![feature(generic_const_exprs)]
 
diff --git a/azalea-core/src/math.rs b/azalea-core/src/math.rs
index 2e5e78f6..40d147e4 100644
--- a/azalea-core/src/math.rs
+++ b/azalea-core/src/math.rs
@@ -1,3 +1,27 @@
+use std::sync::LazyLock;
+
+pub static SIN: LazyLock<[f32; 65536]> = LazyLock::new(|| {
+    let mut sin = [0.0; 65536];
+    for i in 0..65536 {
+        sin[i] = f64::sin((i as f64) * 3.141592653589793 * 2.0 / 65536.0) as f32;
+    }
+    sin
+});
+
+/// A sine function that uses a lookup table.
+pub fn sin(var0: f32) -> f32 {
+    let var0 = var0 * 10430.378;
+    let var0 = var0 as usize;
+    SIN[var0 & 65535]
+}
+
+/// A cosine function that uses a lookup table.
+pub fn cos(var0: f32) -> f32 {
+    let var0 = var0 * 10430.378 + 16384.0;
+    let var0 = var0 as usize;
+    SIN[var0 & 65535]
+}
+
 // TODO: make this generic
 pub fn binary_search(mut min: i32, max: i32, predicate: &dyn Fn(i32) -> bool) -> i32 {
     let mut diff = max - min;