Add support for atlas cached images

Author: dzhou121

src/atlas.rs

@@ -7,12 +7,18 @@ struct ImageData {
     data: Vec<u8>,
 }
 
+pub enum AtlasContent {
+    Mask,
+    Color,
+}
+
 pub struct Atlas {
     packer: Packer,
     new_data: Vec<ImageData>,
     pub atlas_texture: wgpu::Texture,
     area_used: i32,
     did_clear: bool,
+    content: AtlasContent,
 }
 
 impl Atlas {
@@ -50,15 +56,37 @@ impl Atlas {
         }
     }
 
-    pub fn new(device: &wgpu::Device) -> Self {
-        let atlas_texture = device.create_texture(&Self::get_texture_desc());
+    pub fn new(device: &wgpu::Device, content: AtlasContent) -> Self {
+        let texture_size = wgpu::Extent3d {
+            width: Atlas::ATLAS_SIZE,
+            height: Atlas::ATLAS_SIZE,
+            depth_or_array_layers: 1,
+        };
+        let format = match content {
+            AtlasContent::Mask => wgpu::TextureFormat::R8Unorm,
+            AtlasContent::Color => wgpu::TextureFormat::Rgba8Unorm,
+        };
+        let desc = wgpu::TextureDescriptor {
+            size: texture_size,
+            mip_level_count: 1,
+            sample_count: 1,
+            dimension: wgpu::TextureDimension::D2,
+            format,
+            usage: wgpu::TextureUsages::COPY_SRC
+                | wgpu::TextureUsages::COPY_DST
+                | wgpu::TextureUsages::TEXTURE_BINDING,
+            label: Some("atlas_texture"),
+            view_formats: &[format],
+        };
+        let atlas_texture = device.create_texture(&desc);
 
         Self {
             packer: Packer::new(Atlas::get_packer_config()),
             new_data: vec![],
             atlas_texture,
             area_used: 0,
             did_clear: false,
+            content,
         }
     }
 
@@ -78,10 +106,15 @@ impl Atlas {
     }
 
     pub fn update(&mut self, device: &wgpu::Device, encoder: &mut wgpu::CommandEncoder) {
+        let pixels = match self.content {
+            AtlasContent::Mask => 1,
+            AtlasContent::Color => 4,
+        };
+
         if self.did_clear {
             // encoder.clear_texture(&self.atlas_texture, &wgpu::ImageSubresourceRange::default());
 
-            let sz = Atlas::ATLAS_SIZE as usize;
+            let sz = Atlas::ATLAS_SIZE as usize * pixels;
 
             let data = vec![0_u8; sz * sz];
 
@@ -121,14 +154,15 @@ impl Atlas {
         for data in &self.new_data {
             // Pad data to wgpu::COPY_BYTES_PER_ROW_ALIGNMENT
             let align = wgpu::COPY_BYTES_PER_ROW_ALIGNMENT as i32;
-            let padding = (align - data.rect.width % align) % align;
-            let padded_width = data.rect.width + padding;
+            let width = data.rect.width * pixels as i32;
+            let padding = (align - width % align) % align;
+            let padded_width = width + padding;
             let mut padded_data = vec![];
             padded_data.reserve((padded_width * data.rect.height) as usize);
 
             let mut i = 0;
             for _ in 0..data.rect.height {
-                for _ in 0..data.rect.width {
+                for _ in 0..width {
                     padded_data.push(data.data[i]);
                     i += 1;
                 }

src/glyphs.rs

@@ -1,41 +1,110 @@
-use crate::atlas::Atlas;
+use crate::atlas::{Atlas, AtlasContent};
 use rect_packer::Rect;
-use std::collections::HashMap;
+use std::{
+    collections::HashMap,
+    hash::{Hash, Hasher},
+    sync::Arc,
+};
 
 #[derive(Copy, Clone, Debug)]
 pub struct GlyphInfo {
     pub rect: Option<Rect>,
     pub metrics: fontdue::Metrics,
 }
 
-pub struct GlyphCache {
-    pub atlas: Atlas,
+#[derive(Clone, Eq)]
+pub struct ImageId {
+    id: Arc<bool>,
+}
+
+impl ImageId {
+    pub fn new() -> Self {
+        Self {
+            id: Arc::new(false),
+        }
+    }
+}
+
+impl PartialEq for ImageId {
+    fn eq(&self, other: &Self) -> bool {
+        Arc::ptr_eq(&self.id, &other.id)
+    }
+}
+
+impl Hash for ImageId {
+    fn hash<H>(&self, state: &mut H)
+    where
+        H: Hasher,
+    {
+        (Arc::as_ptr(&self.id) as usize).hash(state)
+    }
+}
+
+#[derive(Copy, Clone, Debug)]
+pub struct AtlasImage {
+    pub rect: Option<Rect>,
+}
+
+pub struct AtlasCache {
+    pub mask_atlas: Atlas,
+    pub color_atlas: Atlas,
     pub font: fontdue::Font,
-    info: HashMap<(char, u32), GlyphInfo>,
+    glyphs: HashMap<(char, u32), GlyphInfo>,
+    mask_images: HashMap<ImageId, AtlasImage>,
+    color_images: HashMap<ImageId, AtlasImage>,
 }
 
-impl GlyphCache {
+impl AtlasCache {
     pub fn new(device: &wgpu::Device) -> Self {
         let mut settings = fontdue::FontSettings::default();
         settings.collection_index = 0;
         settings.scale = 100.0;
         let font = include_bytes!("fonts/Anodina-Regular.ttf") as &[u8];
 
         Self {
-            atlas: Atlas::new(device),
+            mask_atlas: Atlas::new(device, AtlasContent::Mask),
+            color_atlas: Atlas::new(device, AtlasContent::Color),
             font: fontdue::Font::from_bytes(font, settings).unwrap(),
-            info: HashMap::new(),
+            glyphs: HashMap::new(),
+            mask_images: HashMap::new(),
+            color_images: HashMap::new(),
         }
     }
 
+    pub fn get_mask_image(
+        &mut self,
+        id: ImageId,
+        width: u32,
+        height: u32,
+        image: impl FnOnce() -> Vec<u8>,
+    ) -> AtlasImage {
+        let mask_atlas = &mut self.mask_atlas;
+        *self.mask_images.entry(id).or_insert_with(|| AtlasImage {
+            rect: mask_atlas.add_region(&image(), width, height),
+        })
+    }
+
+    pub fn get_color_image(
+        &mut self,
+        id: ImageId,
+        width: u32,
+        height: u32,
+        image: impl FnOnce() -> Vec<u8>,
+    ) -> AtlasImage {
+        let color_atlas = &mut self.color_atlas;
+        *self.color_images.entry(id).or_insert_with(|| AtlasImage {
+            rect: color_atlas.add_region(&image(), width, height),
+        })
+    }
+
     pub fn get_glyph(&mut self, c: char, size: f32) -> GlyphInfo {
         let factor = 65536.0;
 
         // Convert size to fixed point so we can hash it.
         let size_fixed_point = (size * factor) as u32;
 
         // Do we already have a glyph?
-        match self.info.get(&(c, size_fixed_point)) {
+        match self.glyphs.get(&(c, size_fixed_point)) {
             Some(info) => *info,
             None => {
                 let (metrics, data) = self.font.rasterize(c, size_fixed_point as f32 / factor);
@@ -52,31 +121,31 @@ impl GlyphCache {
                 */
 
                 let rect =
-                    self.atlas
+                    self.mask_atlas
                         .add_region(&data, metrics.width as u32, metrics.height as u32);
 
                 let info = GlyphInfo { rect, metrics };
 
-                self.info.insert((c, size_fixed_point), info);
+                self.glyphs.insert((c, size_fixed_point), info);
                 info
             }
         }
     }
 
     pub fn update(&mut self, device: &wgpu::Device, encoder: &mut wgpu::CommandEncoder) {
-        self.atlas.update(device, encoder);
+        self.mask_atlas.update(device, encoder);
+        self.color_atlas.update(device, encoder);
     }
 
-    pub fn create_view(&self) -> wgpu::TextureView {
-        self.atlas.create_view()
-    }
-
-    pub fn usage(&self) -> f32 {
-        self.atlas.usage()
-    }
-
-    pub fn clear(&mut self) {
-        self.info.clear();
-        self.atlas.clear();
+    pub fn check_usage(&mut self) {
+        if self.mask_atlas.usage() > 0.7  {
+            self.glyphs.clear();
+            self.mask_atlas.clear();
+            self.mask_images.clear();
+        }
+        if self.color_atlas.usage() > 0.7 {
+            self.color_atlas.clear();
+            self.color_images.clear();
+        }
     }
 }