Implement Vector2 datatypes

packages/lib-roblox/src/datatypes/mod.rs

@@ -4,9 +4,11 @@ pub(crate) use rbx_dom_weak::types::{Variant as RbxVariant, VariantType as RbxVa
 
 // NOTE: We create a new inner module scope here to make imports of datatypes more ergonomic
 
+mod vector2;
 mod vector3;
 
 pub mod types {
+    pub use super::vector2::Vector2;
     pub use super::vector3::Vector3;
 }
 
@@ -25,7 +27,7 @@ pub(crate) enum RbxConversionError {
         detail: Option<String>,
     },
     DesiredTypeMismatch {
-        actual: &'static str,
+        can_convert_to: Option<&'static str>,
         detail: Option<String>,
     },
 }
@@ -47,6 +49,30 @@ pub(crate) trait DatatypeTable {
     fn make_dt_table(lua: &Lua, datatype_table: &LuaTable) -> LuaResult<()>;
 }
 
+// Shared impls for datatype metamethods
+
+fn datatype_impl_to_string<D>(_: &Lua, datatype: &D, _: ()) -> LuaResult<String>
+where
+    D: LuaUserData + ToString + 'static,
+{
+    Ok(datatype.to_string())
+}
+
+fn datatype_impl_eq<D>(_: &Lua, datatype: &D, value: LuaValue) -> LuaResult<bool>
+where
+    D: LuaUserData + PartialEq + 'static,
+{
+    if let LuaValue::UserData(ud) = value {
+        if let Ok(vec) = ud.borrow::<D>() {
+            Ok(*datatype == *vec)
+        } else {
+            Ok(false)
+        }
+    } else {
+        Ok(false)
+    }
+}
+
 // NOTE: This implementation is .. not great, but it's the best we can
 // do since we can't implement a trait like Display on a foreign type,
 // and we are really only using it to make better error messages anyway

packages/lib-roblox/src/datatypes/vector2.rs

@@ -0,0 +1,152 @@
+use core::fmt;
+
+use glam::{Vec2, Vec3A};
+use mlua::prelude::*;
+use rbx_dom_weak::types::Vector2 as RbxVector2;
+
+use super::*;
+
+/**
+    An implementation of the [Vector2](https://create.roblox.com/docs/reference/engine/datatypes/Vector2)
+    Roblox datatype, backed by [`glam::Vec2`].
+
+    This implements all documented properties, methods &
+    constructors of the Vector2 class as of March 2023.
+*/
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub struct Vector2(pub Vec2);
+
+impl fmt::Display for Vector2 {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}, {}", self.0.x, self.0.y)
+    }
+}
+
+impl LuaUserData for Vector2 {
+    fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
+        fields.add_field_method_get("Magnitude", |_, this| Ok(this.0.length()));
+        fields.add_field_method_get("Unit", |_, this| Ok(Vector2(this.0.normalize())));
+        fields.add_field_method_get("X", |_, this| Ok(this.0.x));
+        fields.add_field_method_get("Y", |_, this| Ok(this.0.y));
+    }
+
+    fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
+        // Methods
+        methods.add_method("Cross", |_, this, rhs: Vector2| {
+            let this_v3 = Vec3A::new(this.0.x, this.0.y, 0f32);
+            let rhs_v3 = Vec3A::new(rhs.0.x, rhs.0.y, 0f32);
+            Ok(this_v3.cross(rhs_v3).z)
+        });
+        methods.add_method("Dot", |_, this, rhs: Vector2| Ok(this.0.dot(rhs.0)));
+        methods.add_method("Lerp", |_, this, (rhs, alpha): (Vector2, f32)| {
+            Ok(Vector2(this.0.lerp(rhs.0, alpha)))
+        });
+        methods.add_method("Max", |_, this, rhs: Vector2| {
+            Ok(Vector2(this.0.max(rhs.0)))
+        });
+        methods.add_method("Min", |_, this, rhs: Vector2| {
+            Ok(Vector2(this.0.min(rhs.0)))
+        });
+        // Metamethods
+        methods.add_meta_method(LuaMetaMethod::Eq, datatype_impl_eq);
+        methods.add_meta_method(LuaMetaMethod::ToString, datatype_impl_to_string);
+        methods.add_meta_method(LuaMetaMethod::Unm, |_, this, ()| Ok(Vector2(-this.0)));
+        methods.add_meta_method(LuaMetaMethod::Add, |_, this, rhs: Vector2| {
+            Ok(Vector2(this.0 + rhs.0))
+        });
+        methods.add_meta_method(LuaMetaMethod::Sub, |_, this, rhs: Vector2| {
+            Ok(Vector2(this.0 - rhs.0))
+        });
+        methods.add_meta_method(LuaMetaMethod::Mul, |_, this, rhs: LuaValue| {
+            match &rhs {
+                LuaValue::Number(n) => return Ok(Vector2(this.0 * Vec2::splat(*n as f32))),
+                LuaValue::UserData(ud) => {
+                    if let Ok(vec) = ud.borrow::<Vector2>() {
+                        return Ok(Vector2(this.0 * vec.0));
+                    }
+                }
+                _ => {}
+            };
+            Err(LuaError::FromLuaConversionError {
+                from: rhs.type_name(),
+                to: "Vector2",
+                message: Some(format!(
+                    "Expected Vector2 or number, got {}",
+                    rhs.type_name()
+                )),
+            })
+        });
+        methods.add_meta_method(LuaMetaMethod::Div, |_, this, rhs: LuaValue| {
+            match &rhs {
+                LuaValue::Number(n) => return Ok(Vector2(this.0 / Vec2::splat(*n as f32))),
+                LuaValue::UserData(ud) => {
+                    if let Ok(vec) = ud.borrow::<Vector2>() {
+                        return Ok(Vector2(this.0 / vec.0));
+                    }
+                }
+                _ => {}
+            };
+            Err(LuaError::FromLuaConversionError {
+                from: rhs.type_name(),
+                to: "Vector2",
+                message: Some(format!(
+                    "Expected Vector2 or number, got {}",
+                    rhs.type_name()
+                )),
+            })
+        });
+    }
+}
+
+impl DatatypeTable for Vector2 {
+    fn make_dt_table(lua: &Lua, datatype_table: &LuaTable) -> LuaResult<()> {
+        // Constants
+        datatype_table.set("xAxis", Vector2(Vec2::X))?;
+        datatype_table.set("yAxis", Vector2(Vec2::Y))?;
+        datatype_table.set("zero", Vector2(Vec2::ZERO))?;
+        datatype_table.set("one", Vector2(Vec2::ONE))?;
+        // Constructors
+        datatype_table.set(
+            "new",
+            lua.create_function(|_, (x, y): (Option<f32>, Option<f32>)| {
+                Ok(Vector2(Vec2 {
+                    x: x.unwrap_or_default(),
+                    y: y.unwrap_or_default(),
+                }))
+            })?,
+        )
+    }
+}
+
+impl FromRbxVariant for Vector2 {
+    fn from_rbx_variant(variant: &RbxVariant) -> RbxConversionResult<Self> {
+        if let RbxVariant::Vector2(v) = variant {
+            Ok(Vector2(Vec2 { x: v.x, y: v.y }))
+        } else {
+            Err(RbxConversionError::FromRbxVariant {
+                from: variant.display_name(),
+                to: "Vector2",
+                detail: None,
+            })
+        }
+    }
+}
+
+impl ToRbxVariant for Vector2 {
+    fn to_rbx_variant(
+        &self,
+        desired_type: Option<RbxVariantType>,
+    ) -> RbxConversionResult<RbxVariant> {
+        if matches!(desired_type, None | Some(RbxVariantType::Vector2)) {
+            Ok(RbxVariant::Vector2(RbxVector2 {
+                x: self.0.x,
+                y: self.0.y,
+            }))
+        } else {
+            Err(RbxConversionError::DesiredTypeMismatch {
+                can_convert_to: Some(RbxVariantType::Vector2.display_name()),
+                detail: None,
+            })
+        }
+    }
+}

packages/lib-roblox/src/datatypes/vector3.rs

@@ -16,7 +16,7 @@ use super::*;
     Note that this does not use native Luau vectors to simplify implementation
     and instead allow us to implement all abovementioned APIs accurately.
 */
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 pub struct Vector3(pub Vec3A);
 
 impl fmt::Display for Vector3 {
@@ -58,20 +58,9 @@ impl LuaUserData for Vector3 {
         methods.add_method("Min", |_, this, rhs: Vector3| {
             Ok(Vector3(this.0.min(rhs.0)))
         });
-        // Metamethods - normal
-        methods.add_meta_method(LuaMetaMethod::ToString, |_, this, ()| Ok(this.to_string()));
-        methods.add_meta_method(LuaMetaMethod::Eq, |_, this, rhs: LuaValue| {
-            if let LuaValue::UserData(ud) = rhs {
-                if let Ok(vec) = ud.borrow::<Vector3>() {
-                    Ok(this.0 == vec.0)
-                } else {
-                    Ok(false)
-                }
-            } else {
-                Ok(false)
-            }
-        });
-        // Metamethods - math
+        // Metamethods
+        methods.add_meta_method(LuaMetaMethod::Eq, datatype_impl_eq);
+        methods.add_meta_method(LuaMetaMethod::ToString, datatype_impl_to_string);
         methods.add_meta_method(LuaMetaMethod::Unm, |_, this, ()| Ok(Vector3(-this.0)));
         methods.add_meta_method(LuaMetaMethod::Add, |_, this, rhs: Vector3| {
             Ok(Vector3(this.0 + rhs.0))
@@ -174,7 +163,7 @@ impl ToRbxVariant for Vector3 {
             }))
         } else {
             Err(RbxConversionError::DesiredTypeMismatch {
-                actual: RbxVariantType::Vector3.display_name(),
+                can_convert_to: Some(RbxVariantType::Vector3.display_name()),
                 detail: None,
             })
         }