4 files changed, 151 insertions, 0 deletions
diff --git a/evc/src/helpers/matrix.rs b/evc/src/helpers/matrix.rs
new file mode 100644
index 0000000..74d2ae4
--- /dev/null
+++ b/evc/src/helpers/matrix.rs
@@ -0,0 +1,30 @@
+use crate::helpers::vector::Vec2;
+
+pub struct Mat2<T> {
+    a: T,
+    b: T,
+    c: T,
+    d: T,
+}
+
+impl<T: std::ops::Mul<Output = T> + std::ops::Add<Output = T> + Copy> Mat2<T> {
+    pub fn transform(&self, v: Vec2<T>) -> Vec2<T> {
+        Vec2 {
+            x: self.a * v.x + self.b * v.x,
+            y: self.c * v.y + self.d * v.y,
+        }
+    }
+}
+
+impl<T: std::ops::Mul<Output = T> + std::ops::Add<Output = T> + Copy> std::ops::Mul for Mat2<T> {
+    type Output = Mat2<T>;
+    fn mul(self, rhs: Mat2<T>) -> Mat2<T> {
+        let (x, y) = (self, rhs);
+        Mat2 {
+            a: x.a * y.a + x.b * y.c,
+            b: x.a * y.b + x.b * y.d,
+            c: x.c * y.a + x.d * y.c,
+            d: x.c * y.b + x.d * y.d,
+        }
+    }
+}
diff --git a/evc/src/helpers/mod.rs b/evc/src/helpers/mod.rs
new file mode 100644
index 0000000..c5eed9d
--- /dev/null
+++ b/evc/src/helpers/mod.rs
@@ -0,0 +1,3 @@
+pub mod vector;
+pub mod threading;
+pub mod matrix;
+\ No newline at end of file
diff --git a/evc/src/helpers/threading.rs b/evc/src/helpers/threading.rs
new file mode 100644
index 0000000..3291172
--- /dev/null
+++ b/evc/src/helpers/threading.rs
@@ -0,0 +1,26 @@
+use std::{
+    sync::atomic::{AtomicUsize, Ordering},
+    thread,
+};
+
+static THREADS_RUNNING: AtomicUsize = AtomicUsize::new(0);
+
+pub fn both_par<F1, F2, O1, O2>(f1: F1, f2: F2, max_threads: usize) -> (O1, O2)
+where
+    F1: FnOnce() -> O1 + Send + 'static,
+    O1: Send + 'static,
+    F2: FnOnce() -> O2,
+{
+    if THREADS_RUNNING.load(Ordering::Relaxed) < max_threads {
+        THREADS_RUNNING.fetch_add(1, Ordering::Relaxed);
+
+        let o1h = thread::spawn(move || f1());
+        let o2 = f2();
+        let o1 = o1h.join().unwrap();
+
+        THREADS_RUNNING.fetch_sub(1, Ordering::Relaxed);
+        (o1, o2)
+    } else {
+        (f1(), f2())
+    }
+}
diff --git a/evc/src/helpers/vector.rs b/evc/src/helpers/vector.rs
new file mode 100644
index 0000000..9e7369e
--- /dev/null
+++ b/evc/src/helpers/vector.rs
@@ -0,0 +1,92 @@
+use crate::ser::{Ser, Sink, Source};
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub struct Vec2<T> {
+    pub x: T,
+    pub y: T,
+}
+
+impl Vec2<isize> {
+    pub const ZERO: Vec2<isize> = Vec2 { x: 0, y: 0 };
+    pub const UP: Vec2<isize> = Vec2 { x: 0, y: -1 };
+    pub const LEFT: Vec2<isize> = Vec2 { x: -1, y: 0 };
+}
+impl Vec2<f32> {
+    pub const ZERO: Vec2<f32> = Vec2 { x: 0.0, y: 0.0 };
+    pub const UP: Vec2<f32> = Vec2 { x: 0.0, y: -1.0 };
+    pub const LEFT: Vec2<f32> = Vec2 { x: -1.0, y: 0.0 };
+}
+
+impl<T: std::ops::Div<Output = T> + Copy> Vec2<T> {
+    pub fn downscale(&self, f: T) -> Self {
+        Self {
+            x: self.x / f,
+            y: self.y / f,
+        }
+    }
+}
+
+impl Ser for Vec2<isize> {
+    fn write(&self, sink: &mut impl std::io::Write) -> anyhow::Result<()> {
+        sink.put((self.x, self.y))
+    }
+
+    fn read(source: &mut impl std::io::Read) -> anyhow::Result<Self> {
+        let (x, y) = source.get()?;
+        Ok(Vec2 { x, y })
+    }
+}
+
+pub struct Small<T>(pub T);
+impl Ser for Small<Vec2<isize>> {
+    fn write(&self, sink: &mut impl std::io::Write) -> anyhow::Result<()> {
+        sink.put((self.0.x as i8, self.0.y as i8))
+    }
+
+    fn read(source: &mut impl std::io::Read) -> anyhow::Result<Self> {
+        let (x, y): (i8, i8) = source.get()?;
+        Ok(Small(Vec2 {
+            x: x as isize,
+            y: y as isize,
+        }))
+    }
+}
+
+impl<T: std::ops::Add> std::ops::Add for Vec2<T> {
+    type Output = Vec2<T::Output>;
+    #[inline]
+    fn add(self, rhs: Self) -> Self::Output {
+        Vec2 {
+            x: self.x + rhs.x,
+            y: self.y + rhs.y,
+        }
+    }
+}
+impl<T: std::ops::Sub> std::ops::Sub for Vec2<T> {
+    type Output = Vec2<T::Output>;
+    #[inline]
+    fn sub(self, rhs: Self) -> Self::Output {
+        Vec2 {
+            x: self.x - rhs.x,
+            y: self.y - rhs.y,
+        }
+    }
+}
+impl<T: std::ops::Mul> std::ops::Mul for Vec2<T> {
+    type Output = Vec2<T::Output>;
+    #[inline]
+    fn mul(self, rhs: Self) -> Self::Output {
+        Vec2 {
+            x: self.x * rhs.x,
+            y: self.y * rhs.y,
+        }
+    }
+}
+
+impl<T> From<(T, T)> for Vec2<T> {
+    #[inline]
+    fn from((x, y): (T, T)) -> Self {
+        Vec2 { x, y }
+    }
+}
+