Merge pull request #1110 from godot-rust/feature/f32-process

Support `f32` directly in `process` and `physics_process`

Author: Bromeon

godot-codegen/src/models/domain_mapping.rs

@@ -469,7 +469,6 @@ impl ClassMethod {
         }
 
         let is_private = special_cases::is_method_private(class_name, &method.name);
-
         let godot_method_name = method.name.clone();
 
         let qualifier = {

godot-codegen/src/special_cases/special_cases.rs

@@ -21,6 +21,8 @@
 
 // NOTE: the methods are generally implemented on Godot types (e.g. AABB, not Aabb)
 
+// This file is deliberately private -- all checks must go through `special_cases`.
+
 #![allow(clippy::match_like_matches_macro)] // if there is only one rule
 
 use crate::conv::to_enum_type_uncached;
@@ -30,7 +32,6 @@ use crate::special_cases::codegen_special_cases;
 use crate::util::option_as_slice;
 use crate::Context;
 use proc_macro2::Ident;
-// Deliberately private -- all checks must go through `special_cases`.
 
 #[rustfmt::skip]
 pub fn is_class_method_deleted(class_name: &TyName, method: &JsonClassMethod, ctx: &mut Context) -> bool {
@@ -63,7 +64,7 @@ pub fn is_class_method_deleted(class_name: &TyName, method: &JsonClassMethod, ct
         | ("VisualShaderNodeComment", "set_description")
         | ("VisualShaderNodeComment", "get_description")
         => true,
-        
+
         // Workaround for methods unexposed in Release mode, see https://github.com/godotengine/godot/pull/100317
         // and https://github.com/godotengine/godot/pull/100328.
         #[cfg(not(debug_assertions))]
@@ -849,9 +850,9 @@ pub fn is_enum_private(class_name: Option<&TyName>, enum_name: &str) -> bool {
 }
 
 /// Certain enums that are extremely unlikely to get new identifiers in the future.
-/// 
+///
 /// `class_name` = None for global enums.
-/// 
+///
 /// Very conservative, only includes a few enums. Even `VariantType` was extended over time.
 /// Also does not work for any enums containing duplicate ordinals.
 #[rustfmt::skip]
@@ -882,7 +883,7 @@ pub fn is_enum_bitfield(class_name: Option<&TyName>, enum_name: &str) -> Option<
     match (class_name, enum_name) {
         | (Some("Object"), "ConnectFlags")
 
-        => Some(true), 
+        => Some(true),
         _ => None
     }
 }

godot-core/src/obj/traits.rs

@@ -292,7 +292,7 @@ pub trait WithBaseField: GodotClass + Bounds<Declarer = bounds::DeclUser> {
     ///
     /// #[godot_api]
     /// impl INode for MyClass {
-    ///     fn process(&mut self, _delta: f64) {
+    ///     fn process(&mut self, _delta: f32) {
     ///         let name = self.base().get_name();
     ///         godot_print!("name is {name}");
     ///     }
@@ -318,7 +318,7 @@ pub trait WithBaseField: GodotClass + Bounds<Declarer = bounds::DeclUser> {
     ///
     /// #[godot_api]
     /// impl INode for MyClass {
-    ///     fn process(&mut self, _delta: f64) {
+    ///     fn process(&mut self, _delta: f32) {
     ///         let node = Node::new_alloc();
     ///         // fails because `add_child` requires a mutable reference.
     ///         self.base().add_child(&node);
@@ -361,7 +361,7 @@ pub trait WithBaseField: GodotClass + Bounds<Declarer = bounds::DeclUser> {
     ///
     /// #[godot_api]
     /// impl INode for MyClass {
-    ///     fn process(&mut self, _delta: f64) {
+    ///     fn process(&mut self, _delta: f32) {
     ///         let node = Node::new_alloc();
     ///         self.base_mut().add_child(&node);
     ///     }
@@ -386,7 +386,7 @@ pub trait WithBaseField: GodotClass + Bounds<Declarer = bounds::DeclUser> {
     ///
     /// #[godot_api]
     /// impl INode for MyClass {
-    ///     fn process(&mut self, _delta: f64) {
+    ///     fn process(&mut self, _delta: f32) {
     ///         self.base_mut().call("other_method", &[]);
     ///     }
     /// }

godot-macros/src/class/data_models/func.rs

@@ -187,8 +187,14 @@ pub struct SignatureInfo {
     pub method_name: Ident,
     pub receiver_type: ReceiverType,
     pub param_idents: Vec<Ident>,
+    /// Parameter types *without* receiver.
     pub param_types: Vec<venial::TypeExpr>,
     pub return_type: TokenStream,
+
+    /// `(original index, new type)` only for changed parameters; empty if no changes.
+    ///
+    /// Index points into original venial tokens (i.e. takes into account potential receiver params).
+    pub modified_param_types: Vec<(usize, venial::TypeExpr)>,
 }
 
 impl SignatureInfo {
@@ -199,6 +205,7 @@ impl SignatureInfo {
             param_idents: vec![],
             param_types: vec![],
             return_type: quote! { () },
+            modified_param_types: vec![],
         }
     }
 
@@ -359,7 +366,8 @@ pub(crate) fn into_signature_info(
     };
 
     let mut next_unnamed_index = 0;
-    for (arg, _) in signature.params.inner {
+    let mut modified_param_types = vec![];
+    for (index, (arg, _)) in signature.params.inner.into_iter().enumerate() {
         match arg {
             venial::FnParam::Receiver(recv) => {
                 if receiver_type == ReceiverType::GdSelf {
@@ -377,8 +385,17 @@ pub(crate) fn into_signature_info(
             }
             venial::FnParam::Typed(arg) => {
                 let ident = maybe_rename_parameter(arg.name, &mut next_unnamed_index);
-                let ty = venial::TypeExpr {
-                    tokens: map_self_to_class_name(arg.ty.tokens, class_name),
+                let ty = match maybe_change_parameter_type(arg.ty, &method_name, index) {
+                    // Parameter type was modified.
+                    Ok(ty) => {
+                        modified_param_types.push((index, ty.clone()));
+                        ty
+                    }
+
+                    // Not an error, just unchanged.
+                    Err(ty) => venial::TypeExpr {
+                        tokens: map_self_to_class_name(ty.tokens, class_name),
+                    },
                 };
 
                 param_types.push(ty);
@@ -393,6 +410,28 @@ pub(crate) fn into_signature_info(
         param_idents,
         param_types,
         return_type: ret_type,
+        modified_param_types,
+    }
+}
+
+/// If `f32` is used for a delta parameter in a virtual process function, transparently use `f64` behind the scenes.
+fn maybe_change_parameter_type(
+    param_ty: venial::TypeExpr,
+    method_name: &Ident,
+    param_index: usize,
+) -> Result<venial::TypeExpr, venial::TypeExpr> {
+    // A bit hackish, but TokenStream APIs are also notoriously annoying to work with. Not even PartialEq...
+
+    if param_index == 1
+        && (method_name == "process" || method_name == "physics_process")
+        && param_ty.tokens.len() == 1
+        && param_ty.tokens[0].to_string() == "f32"
+    {
+        Ok(venial::TypeExpr {
+            tokens: vec![TokenTree::Ident(ident("f64"))],
+        })
+    } else {
+        Err(param_ty)
     }
 }