From ca88a2981c5299612381e275c9cfcecc3b895364 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexander=20Mei=C3=9Fner?= <AlexanderMeissner@gmx.net>
Date: Mon, 24 Jul 2023 22:00:30 +0200
Subject: [PATCH] Uses element names instead of indices for the parameters of
 multivector constructors in rust.

---
 codegen/src/emit.rs | 18 +++++++++++++++++-
 codegen/src/rust.rs | 21 +++++++++++++--------
 2 files changed, 30 insertions(+), 9 deletions(-)

diff --git a/codegen/src/emit.rs b/codegen/src/emit.rs
index e80f202..84c79cd 100644
--- a/codegen/src/emit.rs
+++ b/codegen/src/emit.rs
@@ -1,3 +1,5 @@
+use crate::{algebra::BasisElement, ast::AstNode, glsl, rust};
+
 pub fn camel_to_snake_case<W: std::io::Write>(collector: &mut W, name: &str) -> std::io::Result<()> {
     let mut underscores = name.chars().enumerate().filter(|(_i, c)| c.is_uppercase()).map(|(i, _c)| i).peekable();
     for (i, c) in name.to_lowercase().bytes().enumerate() {
@@ -21,7 +23,21 @@ pub fn emit_indentation<W: std::io::Write>(collector: &mut W, indentation: usize
     Ok(())
 }
 
-use crate::{ast::AstNode, glsl, rust};
+pub fn emit_element_name<W: std::io::Write>(collector: &mut W, element: &BasisElement) -> std::io::Result<()> {
+    debug_assert_ne!(element.scalar, 0);
+    if element.index == 0 {
+        collector.write_all(b"scalar")
+    } else {
+        collector.write_all(if element.scalar < 0 { b"_e" } else { b"e" })?;
+        collector.write_all(
+            element
+                .component_bits()
+                .map(|index| format!("{:X}", index))
+                .collect::<String>()
+                .as_bytes(),
+        )
+    }
+}
 
 pub struct Emitter<W: std::io::Write> {
     pub rust_collector: W,
diff --git a/codegen/src/rust.rs b/codegen/src/rust.rs
index 2e7c2ad..5dd19ef 100644
--- a/codegen/src/rust.rs
+++ b/codegen/src/rust.rs
@@ -1,6 +1,6 @@
 use crate::{
     ast::{AstNode, DataType, Expression, ExpressionContent, Parameter},
-    emit::{camel_to_snake_case, emit_indentation},
+    emit::{camel_to_snake_case, emit_element_name, emit_indentation},
 };
 
 fn emit_data_type<W: std::io::Write>(collector: &mut W, data_type: &DataType) -> std::io::Result<()> {
@@ -245,22 +245,27 @@ pub fn emit_code<W: std::io::Write>(collector: &mut W, ast_node: &AstNode, inden
             collector.write_all(b"#[allow(clippy::too_many_arguments)]\n")?;
             emit_indentation(collector, indentation + 1)?;
             collector.write_all(b"pub const fn new(")?;
-            for i in 0..element_count {
-                if i > 0 {
-                    collector.write_all(b", ")?;
+            let mut element_index = 0;
+            for group in class.grouped_basis.iter() {
+                for element in group.iter() {
+                    if element_index > 0 {
+                        collector.write_all(b", ")?;
+                    }
+                    emit_element_name(collector, element)?;
+                    collector.write_all(b": f32")?;
+                    element_index += 1;
                 }
-                collector.write_fmt(format_args!("element{}: f32", i))?;
             }
             collector.write_all(b") -> Self {\n")?;
             emit_indentation(collector, indentation + 2)?;
             collector.write_all(b"Self { elements: [")?;
-            let mut element_index = 0;
+            element_index = 0;
             for (j, group) in class.grouped_basis.iter().enumerate() {
-                for _ in 0..group.len() {
+                for element in group.iter() {
                     if element_index > 0 {
                         collector.write_all(b", ")?;
                     }
-                    collector.write_fmt(format_args!("element{}", element_index))?;
+                    emit_element_name(collector, element)?;
                     element_index += 1;
                 }
                 for _ in group.len()..simd_widths[j] {