From a0ba6f9da3e09c1a65154201cc15475fe173b029 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lera=20Elvo=C3=A9?= <yagich@poto.cafe>
Date: Fri, 14 Feb 2025 22:02:19 +0300
Subject: [PATCH] add lerp function to util and lerp method to vector3

---
 data/scripts/types/vector3.lua | 19 +++++++++++++++++++
 data/scripts/util.lua          | 20 ++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/data/scripts/types/vector3.lua b/data/scripts/types/vector3.lua
index 893313a..5c08f53 100644
--- a/data/scripts/types/vector3.lua
+++ b/data/scripts/types/vector3.lua
@@ -216,6 +216,25 @@ end
 function Vector3:copy()
   return Vector3(self)
 end
+
+---Returns a new vector as a linear interpolation between self and b.
+---@param b vectorlike
+---@param t number
+---@return Vector3
+function Vector3:lerp(b, t)
+  -- return self:copy()
+  if not is_weak_vector3(b) then
+    error("Vector3: b must be a Vector3-like table. Returning copy of self.")
+    return self:copy()
+  end
+  local w = Vector3(b)
+  return Vector3{
+    util.lerp(self.x, w.x, t),
+    util.lerp(self.y, w.y, t),
+    util.lerp(self.z, w.z, t),
+  }
+end
+
 ---- CONSTANTS
 
 Vector3.UP = Vector3(0, 1, 0)
diff --git a/data/scripts/util.lua b/data/scripts/util.lua
index 8329323..1cad958 100644
--- a/data/scripts/util.lua
+++ b/data/scripts/util.lua
@@ -97,4 +97,24 @@ function util.list_insert_once(t, value)
   if util.list_find(t, value) ~= -1 then return end
   table.insert(t, value)
 end
+
+---linear interpolation
+---@param a number
+---@param b number
+---@param t number in [0, 1]
+---@return number
+function util.lerp(a, b, t)
+  return a + t * (b - a)
+end
+
+---constrains v between min and max
+---@param v number
+---@param min number
+---@param max number
+---@return number
+function util.clamp(v, min, max)
+  return math.max(math.min(v, max), min)
+end
+
+
 return util
\ No newline at end of file