feat(texture_atlas): reworked the texture atlas creation

crates/comet_renderer/Cargo.toml

@@ -16,4 +16,4 @@ wgpu = { version = "22.0", features = ["glsl", "wgsl", "naga-ir"]}
 winit = { version = "0.29", features = ["rwh_05"] }
 chrono = "0.4.40"
 pollster = "0.3"
-image = "0.24"
+image = "0.24"

crates/comet_renderer/src/renderer2d.rs

@@ -1,12 +1,12 @@
-use crate::renderer::Renderer;
 use crate::{
     camera::CameraManager,
     render_context::RenderContext,
     render_pass::{universal_clear_execute, universal_load_execute, RenderPass},
+    renderer::Renderer,
 };
 use comet_colors::Color;
 use comet_ecs::{Component, Render, Render2D, Transform2D};
-use comet_log::{debug, error, info};
+use comet_log::*;
 use comet_resources::{
     font::Font, graphic_resource_manager::GraphicResourceManager, texture_atlas::*, Texture, Vertex,
 };
@@ -541,13 +541,28 @@ impl<'a> Renderer2D<'a> {
     }
 
     fn get_glyph_region(&self, glyph: char, font: String) -> &TextureRegion {
-        let font_atlas = self
+        let key = format!("{}::{}", font, glyph);
-            .resource_manager
+
-            .fonts()
+        match self.resource_manager.font_atlas().textures().get(&key) {
-            .iter()
+            Some(region) => region,
-            .find(|f| f.name() == font)
+            None => {
-            .unwrap();
+                warn!(
-        font_atlas.get_glyph(glyph).unwrap()
+                    "Missing glyph for character '{}' in font '{}', using fallback.",
+                    glyph, font
+                );
+                let fallback_key = format!("{}:: ", font);
+                self.resource_manager
+                    .font_atlas()
+                    .textures()
+                    .get(&fallback_key)
+                    .unwrap_or_else(|| {
+                        panic!(
+                            "No fallback glyph available (space also missing) for font '{}'",
+                            font
+                        )
+                    })
+            }
+        }
     }
 
     pub fn add_text_to_buffers(

crates/comet_resources/Cargo.toml

@@ -5,11 +5,12 @@ edition = "2021"
 
 [dependencies]
 comet_log = { path = "../comet_log" }
-wgpu = { version = "22.0", features = ["spirv"] }
+wgpu = { version = "22.0", features = ["glsl", "wgsl", "naga-ir"] }
 anyhow = "1.0"
 bytemuck = { version = "1.16", features = [ "derive" ] }
 ab_glyph = "0.2.29"
 chrono = "0.4.40"
+rect_packer = "0.2.1"
 
 [dependencies.image]
 version = "0.24"

crates/comet_resources/src/graphic_resource_manager.rs

@@ -6,10 +6,7 @@ use crate::{
     Texture,
 };
 use comet_log::info;
-use wgpu::{
+use wgpu::{naga::ShaderStage, Device, Queue, ShaderModule};
-    naga::{self, ShaderStage},
-    Device, Queue, ShaderModule,
-};
 
 pub struct GraphicResourceManager {
     texture_atlas: TextureAtlas,
@@ -127,7 +124,7 @@ impl GraphicResourceManager {
                         source: wgpu::ShaderSource::Glsl {
                             shader: shader_source.into(),
                             stage,
-                            defines: naga::FastHashMap::default(),
+                            defines: Default::default(),
                         },
                     })
                 } else {

crates/comet_resources/src/texture_atlas.rs

@@ -1,6 +1,7 @@
 use crate::font::*;
 use comet_log::*;
-use image::{DynamicImage, GenericImage, GenericImageView};
+use image::{DynamicImage, GenericImage, GenericImageView, RgbaImage};
+use rect_packer::{Config, Packer, Rect};
 use std::collections::HashMap;
 use std::path::Path;
 
@@ -81,335 +82,332 @@ pub struct TextureAtlas {
 impl TextureAtlas {
     pub fn empty() -> Self {
         Self {
-            atlas: DynamicImage::new(1, 1, image::ColorType::Rgb8),
+            atlas: DynamicImage::new_rgba8(1, 1),
             textures: HashMap::new(),
         }
     }
 
     pub fn texture_paths(&self) -> Vec<String> {
-        self.textures.keys().map(|k| k.to_string()).collect()
+        self.textures.keys().cloned().collect()
     }
 
-    fn calculate_atlas_width(textures: &Vec<DynamicImage>) -> u32 {
+    #[inline(always)]
-        let mut last_height: u32 = textures.get(0).unwrap().height();
+    fn next_power_of_two(mut x: u32) -> u32 {
-        let mut widths: Vec<u32> = Vec::new();
+        if x == 0 {
-        let mut current_width: u32 = 0;
+            return 1;
-
-        for texture in textures {
-            if last_height != texture.height() {
-                widths.push(current_width);
-                current_width = 0;
-                last_height = texture.height();
-            }
-            current_width += texture.width();
         }
-
+        x -= 1;
-        widths.push(current_width);
+        x |= x >> 1;
-
+        x |= x >> 2;
-        *widths.iter().max().unwrap()
+        x |= x >> 4;
+        x |= x >> 8;
+        x |= x >> 16;
+        x + 1
     }
 
-    fn calculate_atlas_height(textures: &Vec<DynamicImage>) -> u32 {
+    fn pack_textures(
-        let last_height: u32 = textures.get(0).unwrap().height();
+        textures: &[(&String, &DynamicImage)],
-        let mut height: u32 = 0;
+        padding: u32,
-        height += last_height;
+    ) -> (u32, u32, HashMap<String, Rect>) {
+        let mut atlas_size = 512;
+        let max_size = 8192;
 
-        for texture in textures {
+        let valid_textures: Vec<(String, DynamicImage)> = textures
-            if last_height == texture.height() {
+            .iter()
-                continue;
+            .map(|(name, tex)| {
-            }
+                let (w, h) = (tex.width(), tex.height());
+                if w == 0 || h == 0 {
+                    warn!(
+                        "Texture '{}' has invalid size {}x{}, replacing with 1x1 transparent dummy.",
+                        name, w, h
+                    );
+                    let mut img = RgbaImage::new(1, 1);
+                    img.put_pixel(0, 0, image::Rgba([0, 0, 0, 0]));
+                    (name.to_string(), DynamicImage::ImageRgba8(img))
+                } else {
+                    ((*name).clone(), (*tex).clone())
+                }
+            })
+            .collect();
 
-            height += texture.height();
+        if valid_textures.is_empty() {
+            error!("No valid textures to pack!");
+            return (0, 0, HashMap::new());
         }
 
-        height
+        loop {
+            let config = Config {
+                width: atlas_size as i32,
+                height: atlas_size as i32,
+                border_padding: padding as i32,
+                rectangle_padding: padding as i32,
+            };
+
+            let mut packer = Packer::new(config);
+            let mut placements = HashMap::new();
+            let mut max_x = 0i32;
+            let mut max_y = 0i32;
+            let mut failed = false;
+
+            for (name, tex) in &valid_textures {
+                let width = tex.width() as i32;
+                let height = tex.height() as i32;
+
+                if width > atlas_size as i32 || height > atlas_size as i32 {
+                    error!(
+                        "Texture '{}' is too large ({width}x{height}) for current atlas size {atlas_size}x{atlas_size}",
+                        name
+                    );
+                    failed = true;
+                    break;
+                }
+
+                if let Some(rect) = packer.pack(width, height, false) {
+                    max_x = max_x.max(rect.x + rect.width);
+                    max_y = max_y.max(rect.y + rect.height);
+                    placements.insert(name.clone(), rect);
+                } else {
+                    failed = true;
+                    break;
+                }
+            }
+
+            if failed {
+                if atlas_size >= max_size {
+                    error!(
+                        "Failed to pack all textures even at max atlas size ({}x{}).",
+                        max_size, max_size
+                    );
+                    return (max_x as u32, max_y as u32, placements);
+                }
+
+                info!(
+                    "Atlas size {}x{} too small, doubling to {}x{}...",
+                    atlas_size,
+                    atlas_size,
+                    atlas_size * 2,
+                    atlas_size * 2
+                );
+                atlas_size *= 2;
+            } else {
+                info!(
+                    "Created texture atlas ({}x{}) with {} textures.",
+                    atlas_size,
+                    atlas_size,
+                    placements.len()
+                );
+                return (max_x as u32, max_y as u32, placements);
+            }
+        }
     }
 
-    fn insert_texture_at(base: &mut DynamicImage, texture: &DynamicImage, x_pos: u32, y_pos: u32) {
+    fn build_atlas(
-        for y in 0..texture.height() {
+        textures: &[(&String, &DynamicImage)],
-            for x in 0..texture.width() {
+        placements: &HashMap<String, Rect>,
-                let pixel = texture.get_pixel(x, y);
+        atlas_width: u32,
-                base.put_pixel(x + x_pos, y + y_pos, pixel);
+        atlas_height: u32,
+    ) -> (RgbaImage, HashMap<String, TextureRegion>) {
+        let mut base = RgbaImage::new(atlas_width, atlas_height);
+        let mut regions = HashMap::new();
+
+        for (name, tex) in textures {
+            if let Some(rect) = placements.get(*name) {
+                base.copy_from(&tex.to_rgba8(), rect.x as u32, rect.y as u32)
+                    .unwrap_or_else(|_| {
+                        panic!(
+                            "Failed to blit texture '{}' into atlas at ({}, {})",
+                            name, rect.x, rect.y
+                        )
+                    });
+
+                let u0 = rect.x as f32 / atlas_width as f32;
+                let v0 = rect.y as f32 / atlas_height as f32;
+                let u1 = (rect.x + rect.width) as f32 / atlas_width as f32;
+                let v1 = (rect.y + rect.height) as f32 / atlas_height as f32;
+
+                regions.insert(
+                    (*name).clone(),
+                    TextureRegion::new(
+                        u0,
+                        v0,
+                        u1,
+                        v1,
+                        (rect.width as u32, rect.height as u32),
+                        0.0,
+                        0.0,
+                        0.0,
+                    ),
+                );
             }
         }
+
+        (base, regions)
     }
 
     pub fn from_texture_paths(paths: Vec<String>) -> Self {
-        let mut textures: Vec<DynamicImage> = Vec::new();
+        let mut textures = Vec::new();
-        let mut regions: HashMap<String, TextureRegion> = HashMap::new();
 
         info!("Loading textures...");
-
         for path in &paths {
-            textures.push(image::open(&Path::new(path.as_str())).expect("Failed to load texture"));
+            let img = image::open(Path::new(path)).expect("Failed to load texture");
+            textures.push((path, img));
         }
 
-        info!("Textures loaded!");
+        info!("Packing textures...");
-        info!("Sorting textures by height...");
+        let tex_refs: Vec<(&String, &DynamicImage)> =
+            textures.iter().map(|(p, i)| (*p, i)).collect();
 
-        let mut texture_path_pairs: Vec<(&DynamicImage, &String)> =
+        let (atlas_w, atlas_h, placements) = Self::pack_textures(&tex_refs, 2);
-            textures.iter().zip(paths.iter()).collect();
-        texture_path_pairs.sort_by(|a, b| b.0.height().cmp(&a.0.height()));
-        let (sorted_textures, sorted_paths): (Vec<&DynamicImage>, Vec<&String>) =
-            texture_path_pairs.into_iter().unzip();
-        let sorted_textures: Vec<DynamicImage> =
-            sorted_textures.into_iter().map(|t| t.clone()).collect();
-        let sorted_paths: Vec<String> = sorted_paths.into_iter().map(|s| s.to_string()).collect();
 
-        let (height, width) = (
+        let atlas_w = Self::next_power_of_two(atlas_w);
-            Self::calculate_atlas_height(&sorted_textures),
+        let atlas_h = Self::next_power_of_two(atlas_h);
-            Self::calculate_atlas_width(&sorted_textures),
+
+        let (base, regions) = Self::build_atlas(&tex_refs, &placements, atlas_w, atlas_h);
+
+        info!(
+            "Created texture atlas ({}x{}) with {} textures.",
+            atlas_w,
+            atlas_h,
+            regions.len()
         );
-        let mut base = DynamicImage::new_rgba8(width, height);
-
-        let mut previous = sorted_textures.get(0).unwrap().height();
-        let mut x_offset: u32 = 0;
-        let mut y_offset: u32 = 0;
-
-        info!("Creating texture atlas...");
-
-        for (texture, path) in sorted_textures.iter().zip(sorted_paths.iter()) {
-            if texture.height() != previous {
-                y_offset += previous;
-                x_offset = 0;
-                previous = texture.height();
-            }
-
-            Self::insert_texture_at(&mut base, &texture, x_offset, y_offset);
-            let texel_w = 0.5 / width as f32;
-            let texel_h = 0.5 / height as f32;
-
-            let u0 = (x_offset as f32 + texel_w) / width as f32;
-            let v0 = (y_offset as f32 + texel_h) / height as f32;
-            let u1 = ((x_offset + texture.width()) as f32 - texel_w) / width as f32;
-            let v1 = ((y_offset + texture.height()) as f32 - texel_h) / height as f32;
-
-            regions.insert(
-                path.to_string(),
-                TextureRegion::new(u0, v0, u1, v1, texture.dimensions(), 0.0, 0.0, 0.0),
-            );
-            x_offset += texture.width();
-        }
-
-        info!("Texture atlas created!");
 
         TextureAtlas {
-            atlas: base,
+            atlas: DynamicImage::ImageRgba8(base),
             textures: regions,
         }
     }
 
     pub fn from_textures(names: Vec<String>, textures: Vec<DynamicImage>) -> Self {
-        let mut regions: HashMap<String, TextureRegion> = HashMap::new();
+        assert_eq!(
-
+            names.len(),
-        info!("Sorting textures by height...");
+            textures.len(),
-
+            "Names and textures must have the same length."
-        let mut texture_path_pairs: Vec<(&DynamicImage, &String)> =
-            textures.iter().zip(names.iter()).collect();
-        texture_path_pairs.sort_by(|a, b| b.0.height().cmp(&a.0.height()));
-        let (sorted_textures, sorted_paths): (Vec<&DynamicImage>, Vec<&String>) =
-            texture_path_pairs.into_iter().unzip();
-        let sorted_textures: Vec<DynamicImage> =
-            sorted_textures.into_iter().map(|t| t.clone()).collect();
-        let sorted_paths: Vec<String> = sorted_paths.into_iter().map(|s| s.to_string()).collect();
-
-        let (height, width) = (
-            Self::calculate_atlas_height(&sorted_textures),
-            Self::calculate_atlas_width(&sorted_textures),
         );
-        let mut base = DynamicImage::new_rgba8(width, height);
 
-        let mut previous = sorted_textures.get(0).unwrap().height();
+        let tex_refs: Vec<(&String, &DynamicImage)> = names.iter().zip(textures.iter()).collect();
-        let mut x_offset: u32 = 0;
-        let mut y_offset: u32 = 0;
 
-        info!("Creating texture atlas...");
+        let (atlas_w, atlas_h, placements) = Self::pack_textures(&tex_refs, 2);
+        let atlas_w = Self::next_power_of_two(atlas_w);
+        let atlas_h = Self::next_power_of_two(atlas_h);
 
-        for (texture, name) in sorted_textures.iter().zip(sorted_paths.iter()) {
+        let (base, regions) = Self::build_atlas(&tex_refs, &placements, atlas_w, atlas_h);
-            if texture.height() != previous {
-                y_offset += previous;
-                x_offset = 0;
-                previous = texture.height();
-            }
-
-            Self::insert_texture_at(&mut base, &texture, x_offset, y_offset);
-            regions.insert(
-                name.to_string(),
-                TextureRegion::new(
-                    x_offset as f32 / width as f32,
-                    y_offset as f32 / height as f32,
-                    (x_offset + texture.width()) as f32 / width as f32,
-                    (y_offset + texture.height()) as f32 / height as f32,
-                    texture.dimensions(),
-                    0.0,
-                    0.0,
-                    0.0,
-                ),
-            );
-            x_offset += texture.width();
-        }
-
-        info!("Texture atlas created!");
 
         TextureAtlas {
-            atlas: base,
+            atlas: DynamicImage::ImageRgba8(base),
             textures: regions,
         }
     }
 
-    pub fn from_glyphs(mut glyphs: Vec<GlyphData>) -> Self {
+    pub fn from_glyphs(glyphs: Vec<GlyphData>) -> Self {
-        glyphs.sort_by(|a, b| b.render.height().cmp(&a.render.height()));
+        let textures: Vec<(String, DynamicImage)> = glyphs
+            .iter()
+            .map(|g| (g.name.clone(), g.render.clone()))
+            .collect();
 
-        let height = Self::calculate_atlas_height(
+        let tex_refs: Vec<(&String, &DynamicImage)> =
-            &glyphs.iter().map(|g| g.render.clone()).collect::<Vec<_>>(),
+            textures.iter().map(|(n, i)| (n, i)).collect();
-        );
-        let width = Self::calculate_atlas_width(
-            &glyphs.iter().map(|g| g.render.clone()).collect::<Vec<_>>(),
-        );
 
-        let padding = (glyphs.len() * 3) as u32;
+        let (atlas_w, atlas_h, placements) = Self::pack_textures(&tex_refs, 2);
+        let atlas_w = Self::next_power_of_two(atlas_w);
+        let atlas_h = Self::next_power_of_two(atlas_h);
 
-        let mut base = DynamicImage::new_rgba8(width + padding, height);
+        let mut base = RgbaImage::new(atlas_w, atlas_h);
         let mut regions = HashMap::new();
-        let mut current_row_height = glyphs[0].render.height();
-        let mut x_offset: u32 = 0;
-        let mut y_offset: u32 = 0;
 
         for g in glyphs.iter() {
-            let glyph_w = g.render.width();
+            if let Some(rect) = placements.get(&g.name) {
-            let glyph_h = g.render.height();
+                base.copy_from(&g.render.to_rgba8(), rect.x as u32, rect.y as u32)
+                    .unwrap();
 
-            if glyph_h != current_row_height {
+                let u0 = rect.x as f32 / atlas_w as f32;
-                y_offset += current_row_height + 3;
+                let v0 = rect.y as f32 / atlas_h as f32;
-                x_offset = 0;
+                let u1 = (rect.x + rect.width) as f32 / atlas_w as f32;
-                current_row_height = glyph_h;
+                let v1 = (rect.y + rect.height) as f32 / atlas_h as f32;
+
+                let region = TextureRegion::new(
+                    u0,
+                    v0,
+                    u1,
+                    v1,
+                    (rect.width as u32, rect.height as u32),
+                    g.advance,
+                    g.offset_x,
+                    g.offset_y,
+                );
+
+                regions.insert(g.name.clone(), region);
             }
-
-            Self::insert_texture_at(&mut base, &g.render, x_offset, y_offset);
-
-            let u0 = x_offset as f32 / (width + padding) as f32;
-            let v0 = y_offset as f32 / height as f32;
-            let u1 = (x_offset + glyph_w) as f32 / (width + padding) as f32;
-            let v1 = (y_offset + glyph_h) as f32 / height as f32;
-
-            let region = TextureRegion::new(
-                u0,
-                v0,
-                u1,
-                v1,
-                (glyph_w, glyph_h),
-                g.advance,
-                g.offset_x,
-                g.offset_y,
-            );
-
-            regions.insert(g.name.clone(), region);
-
-            x_offset += glyph_w + 3;
         }
 
         TextureAtlas {
-            atlas: base,
+            atlas: DynamicImage::ImageRgba8(base),
             textures: regions,
         }
     }
 
-    pub fn from_fonts(fonts: &Vec<Font>) -> Self {
+    pub fn from_fonts(fonts: &[Font]) -> Self {
         if fonts.is_empty() {
             return Self::empty();
         }
 
-        let mut all_glyphs: Vec<(String, DynamicImage, TextureRegion)> = Vec::new();
+        let mut all_glyphs = Vec::new();
 
-        let mut font_indices: Vec<usize> = (0..fonts.len()).collect();
+        for font in fonts {
-        font_indices.sort_by(|&a, &b| fonts[a].name().cmp(&fonts[b].name()));
-
-        for fi in font_indices {
-            let font = &fonts[fi];
             let font_name = font.name();
+            let src_atlas = font.glyphs().atlas();
+            let atlas_width = src_atlas.width();
+            let atlas_height = src_atlas.height();
 
-            let mut glyph_names: Vec<String> = font.glyphs().textures().keys().cloned().collect();
+            for (glyph_name, region) in font.glyphs().textures() {
-            glyph_names.sort();
+                let src_x = (region.u0() * atlas_width as f32) as u32;
+                let src_y = (region.v0() * atlas_height as f32) as u32;
+                let width = region.dimensions().0;
+                let height = region.dimensions().1;
 
-            for glyph_name in glyph_names {
+                let glyph_img = src_atlas.view(src_x, src_y, width, height).to_image();
-                let region = font.glyphs().textures().get(&glyph_name).unwrap();
-
-                let (u0, v0) = (region.u0(), region.v0());
-                let (width, height) = region.dimensions();
-
-                let src_x = (u0 * font.glyphs().atlas().width() as f32) as u32;
-                let src_y = (v0 * font.glyphs().atlas().height() as f32) as u32;
-
-                let glyph_img = DynamicImage::ImageRgba8(
-                    font.glyphs()
-                        .atlas()
-                        .view(src_x, src_y, width, height)
-                        .to_image(),
-                );
 
                 let key = format!("{}::{}", font_name, glyph_name);
-
+                all_glyphs.push((key, DynamicImage::ImageRgba8(glyph_img), region.clone()));
-                all_glyphs.push((key, glyph_img, region.clone()));
             }
         }
 
-        all_glyphs.sort_by(|a, b| {
+        let tex_refs: Vec<(&String, &DynamicImage)> =
-            let ha = a.1.height();
+            all_glyphs.iter().map(|(n, i, _)| (n, i)).collect();
-            let hb = b.1.height();
+        let (atlas_w, atlas_h, placements) = Self::pack_textures(&tex_refs, 2);
-            match hb.cmp(&ha) {
+        let atlas_w = Self::next_power_of_two(atlas_w);
-                std::cmp::Ordering::Equal => a.0.cmp(&b.0),
+        let atlas_h = Self::next_power_of_two(atlas_h);
-                other => other,
-            }
-        });
 
-        let textures: Vec<DynamicImage> =
+        let mut base = RgbaImage::new(atlas_w, atlas_h);
-            all_glyphs.iter().map(|(_, img, _)| img.clone()).collect();
-        let atlas_height = Self::calculate_atlas_height(&textures);
-        let atlas_width = Self::calculate_atlas_width(&textures);
-
-        let padding = (all_glyphs.len() * 3) as u32;
-        let mut base = DynamicImage::new_rgba8(atlas_width + padding, atlas_height);
         let mut regions = HashMap::new();
 
-        let mut current_row_height = textures[0].height();
-        let mut x_offset: u32 = 0;
-        let mut y_offset: u32 = 0;
-
         for (key, img, original_region) in all_glyphs {
-            let w = img.width();
+            if let Some(rect) = placements.get(&key) {
-            let h = img.height();
+                base.copy_from(&img.to_rgba8(), rect.x as u32, rect.y as u32)
+                    .unwrap();
 
-            if h != current_row_height {
+                let u0 = rect.x as f32 / atlas_w as f32;
-                y_offset += current_row_height + 3;
+                let v0 = rect.y as f32 / atlas_h as f32;
-                x_offset = 0;
+                let u1 = (rect.x + rect.width) as f32 / atlas_w as f32;
-                current_row_height = h;
+                let v1 = (rect.y + rect.height) as f32 / atlas_h as f32;
+
+                regions.insert(
+                    key,
+                    TextureRegion::new(
+                        u0,
+                        v0,
+                        u1,
+                        v1,
+                        (rect.width as u32, rect.height as u32),
+                        original_region.advance(),
+                        original_region.offset_x(),
+                        original_region.offset_y(),
+                    ),
+                );
             }
-
-            Self::insert_texture_at(&mut base, &img, x_offset, y_offset);
-
-            let u0 = x_offset as f32 / (atlas_width + padding) as f32;
-            let v0 = y_offset as f32 / atlas_height as f32;
-            let u1 = (x_offset + w) as f32 / (atlas_width + padding) as f32;
-            let v1 = (y_offset + h) as f32 / atlas_height as f32;
-
-            let region = TextureRegion::new(
-                u0,
-                v0,
-                u1,
-                v1,
-                (w, h),
-                original_region.advance(),
-                original_region.offset_x(),
-                original_region.offset_y(),
-            );
-
-            regions.insert(key, region);
-
-            x_offset += w + 3;
         }
 
         TextureAtlas {
-            atlas: base,
+            atlas: DynamicImage::ImageRgba8(base),
             textures: regions,
         }
     }