Switch entirely to using quote to generate the code

agb-image-converter/src/lib.rs

@@ -3,7 +3,7 @@ use syn::parse_macro_input;
 
 use std::path::Path;
 
-use quote::{quote, format_ident};
+use quote::{format_ident, quote};
 
 mod colour;
 mod config;
@@ -44,13 +44,18 @@ pub fn include_gfx(input: TokenStream) -> TokenStream {
 
     let config = config::parse(&path.to_string_lossy());
 
-    let module_name = format_ident!("{}", path.file_stem().expect("Expected a file stem").to_string_lossy());
+    let module_name = format_ident!(
+        "{}",
+        path.file_stem()
+            .expect("Expected a file stem")
+            .to_string_lossy()
+    );
     let include_path = path.to_string_lossy();
 
     let images = config.images();
-    let image_code = images
+    let image_code = images.iter().map(|(image_name, &image)| {
-        .iter()
+        convert_image(image, parent, &image_name, &config.crate_prefix())
-        .map(|(image_name, &image)| convert_image(image, parent, &image_name, &config.crate_prefix()));
+    });
 
     let module = quote! {
         pub mod #module_name {
@@ -80,19 +85,14 @@ fn convert_image(
     let optimiser = optimiser_for_image(&image, tile_size);
     let optimisation_results = optimiser.optimise_palettes(settings.transparent_colour());
 
-    let mut writer = String::new();
-
     rust_generator::generate_code(
-        &mut writer,
         variable_name,
         &optimisation_results,
         &image,
         &image_filename.to_string_lossy(),
         settings.tilesize(),
         crate_prefix.to_owned(),
-    );
+    )
-
-    writer.parse().unwrap()
 }
 
 fn optimiser_for_image(image: &Image, tile_size: usize) -> palette16::Palette16Optimiser {

agb-image-converter/src/rust_generator.rs

@@ -1,121 +1,87 @@
-use std::fmt::Write;
-
 use crate::image_loader::Image;
 use crate::palette16::Palette16OptimisationResults;
 use crate::TileSize;
 
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote};
+
+use std::iter;
+
 pub(crate) fn generate_code(
-    output: &mut dyn Write,
     output_variable_name: &str,
     results: &Palette16OptimisationResults,
     image: &Image,
     image_filename: &str,
     tile_size: TileSize,
     crate_prefix: String,
-) {
+) -> TokenStream {
-    writeln!(output, "#[allow(non_upper_case_globals)]").unwrap();
+    let crate_prefix = format_ident!("{}", crate_prefix);
-    writeln!(
+    let output_variable_name = format_ident!("{}", output_variable_name);
-        output,
-        "pub const {}: {}::display::tile_data::TileData = {{",
-        output_variable_name, crate_prefix
-    )
-    .unwrap();
 
-    writeln!(
+    let palette_data = results.optimised_palettes.iter().map(|palette| {
-        output,
+        let colours = palette
-        "const _: &[u8] = include_bytes!(\"{}\");",
+            .clone()
-        image_filename
+            .into_iter()
-    )
+            .map(|colour| colour.to_rgb15())
-    .unwrap();
+            .chain(iter::repeat(0))
+            .take(16);
 
-    writeln!(
+        quote! {
-        output,
+            #crate_prefix::display::palette16::Palette16::new([
-        "const PALETTE_DATA: &[{}::display::palette16::Palette16] = &[",
+                #(#colours),*
-        crate_prefix,
+            ])
-    )
-    .unwrap();
-
-    for palette in &results.optimised_palettes {
-        write!(
-            output,
-            "    {}::display::palette16::Palette16::new([",
-            crate_prefix
-        )
-        .unwrap();
-
-        for colour in palette.clone() {
-            write!(output, "0x{:08x}, ", colour.to_rgb15()).unwrap();
         }
-
+    });
-        for _ in palette.clone().into_iter().len()..16 {
-            write!(output, "0x00000000, ").unwrap();
-        }
-
-        writeln!(output, "]),").unwrap();
-    }
-
-    writeln!(output, "];").unwrap();
-    writeln!(output).unwrap();
-
-    writeln!(output, "const TILE_DATA: &[u32] = &[",).unwrap();
 
     let tile_size = tile_size.to_size();
 
     let tiles_x = image.width / tile_size;
     let tiles_y = image.height / tile_size;
 
-    for y in 0..tiles_y {
+    let tile_data = (0..tiles_y)
-        for x in 0..tiles_x {
+        .map(|y| {
-            let palette_index = results.assignments[y * tiles_x + x];
+            (0..tiles_x).map(move |x| {
-            let palette = &results.optimised_palettes[palette_index];
+                let palette_index = results.assignments[y * tiles_x + x];
-            writeln!(
+                let palette = &results.optimised_palettes[palette_index];
-                output,
-                "    /* {}, {} (palette index {}) */",
-                x, y, palette_index
-            )
-            .unwrap();
 
-            for inner_y in 0..tile_size / 8 {
+                (0..tile_size / 8).map(move |inner_y| {
-                write!(output, "    ").unwrap();
+                    (0..tile_size / 8).map(move |inner_x| {
+                        (inner_y * 8..inner_y * 8 + 8).map(move |j| {
+                            (inner_x * 8..inner_x * 8 + 8).rev().map(move |i| {
+                                let colour = image.colour(x * tile_size + i, y * tile_size + j);
+                                palette.colour_index(colour)
+                            })
+                        })
+                    })
+                })
+            })
+        })
+        .flatten()
+        .flatten()
+        .flatten()
+        .flatten()
+        .flatten();
 
-                for inner_x in 0..tile_size / 8 {
+    let assignments = &results.assignments;
-                    for j in inner_y * 8..inner_y * 8 + 8 {
-                        write!(output, "0x").unwrap();
 
-                        for i in (inner_x * 8..inner_x * 8 + 8).rev() {
+    quote! {
-                            let colour = image.colour(x * tile_size + i, y * tile_size + j);
+        #[allow(non_upper_case_globals)]
-                            let colour_index = palette.colour_index(colour);
+        pub const #output_variable_name: #crate_prefix::display::tile_data::TileData = {
+            const _: &[u8] = include_bytes!(#image_filename);
 
-                            write!(output, "{:x}", colour_index).unwrap();
+            const PALETTE_DATA: &[#crate_prefix::display::palette16::Palette16] = &[
-                        }
+                #(#palette_data),*
+            ];
 
-                        write!(output, ", ").unwrap();
+            const TILE_DATA: &[u32] = &[
-                    }
+                #(#tile_data),*
-                }
+            ];
-            }
 
-            writeln!(output).unwrap();
+            const PALETTE_ASSIGNMENT: &[u8] = &[
-        }
+                #(#assignments),*
+            ];
+
+            #crate_prefix::display::tile_data::TileData::new(PALETTE_DATA, TILE_DATA, PALETTE_ASSIGNMENT)
+        };
     }
-
-    writeln!(output, "];").unwrap();
-    writeln!(output).unwrap();
-
-    write!(output, "const PALETTE_ASSIGNMENT: &[u8] = &[").unwrap();
-
-    for (i, assignment) in results.assignments.iter().enumerate() {
-        if i % 16 == 0 {
-            write!(output, "\n    ").unwrap();
-        }
-        write!(output, "{}, ", assignment).unwrap();
-    }
-
-    writeln!(output, "\n];").unwrap();
-
-    writeln!(
-        output,
-        "{}::display::tile_data::TileData::new(PALETTE_DATA, TILE_DATA, PALETTE_ASSIGNMENT)\n}};",
-        crate_prefix
-    )
-    .unwrap();
 }