[oden][game] Draw the world

This involved basically a giant rewrite of the renderer because I now
need to share the vertex buffer across textures and it is *a lot* let
me tell you.

There's like a vertical seam which I don't understand yet.

game/level.ts

@@ -0,0 +1,141 @@
+// NOTE: It's super not clear how much of this should be in rust vs
+//       javascript. Dealing with the level code is really nice in javascript
+//       but there's a bunch of weird stuff that really feels lower level.
+import { load_texture } from "./assets";
+import { Texture, print, spr, use_texture } from "./graphics";
+import { load_string } from "./io";
+
+// TODO: Use io-ts? YIKES.
+
+export type Tile = {
+  px: [number, number];
+  src: [number, number];
+  f: number;
+  t: number;
+  a: number;
+};
+
+export type TileLayer = {
+  type: "tile";
+  texture: Texture;
+  grid_size: number;
+  offset: [number, number];
+  tiles: Tile[];
+};
+
+export type Layer = TileLayer;
+
+export type Level = {
+  world_x: number;
+  world_y: number;
+  width: number;
+  height: number;
+  layers: Layer[];
+};
+
+export type TileSet = { id: number; texture: Texture };
+
+export type World = { levels: Level[]; tilesets: Map<number, TileSet> };
+
+async function load_tileset(def: {
+  uid: number;
+  relPath: string;
+}): Promise<TileSet> {
+  let relPath = def.relPath as string;
+  if (relPath.endsWith(".aseprite")) {
+    // Whoops let's load the export instead?
+    relPath = relPath.substring(0, relPath.length - 8) + "png";
+  }
+  let texture = await load_texture(relPath);
+
+  print("Loaded tileset", def.uid, "from", relPath, "as ID", texture.id());
+  return { id: def.uid, texture };
+}
+
+function load_level(
+  tile_sets: Map<number, TileSet>,
+  def: {
+    worldX: number;
+    worldY: number;
+    pxWid: number;
+    pxHei: number;
+    layerInstances: {
+      __gridSize: number;
+      __pxTotalOffsetX: number;
+      __pxTotalOffsetY: number;
+      __tilesetDefUid: number;
+      gridTiles: {
+        px: [number, number];
+        src: [number, number];
+        f: number;
+        t: number;
+        a: number;
+      }[];
+    }[];
+  }
+): Level {
+  return {
+    world_x: def.worldX,
+    world_y: def.worldY,
+    width: def.pxWid,
+    height: def.pxHei,
+    layers: def.layerInstances.map((li) => {
+      const tileset = tile_sets.get(li.__tilesetDefUid);
+      if (!tileset) {
+        throw new Error("Unable to find texture!!! " + li.__tilesetDefUid);
+      }
+
+      return {
+        type: "tile",
+        texture: tileset.texture,
+        grid_size: li.__gridSize,
+        offset: [li.__pxTotalOffsetX, li.__pxTotalOffsetY],
+        tiles: li.gridTiles,
+      };
+    }),
+  };
+}
+
+export async function load_world(path: string): Promise<World> {
+  print("Loading map:", path);
+  const blob = await load_string(path);
+  const map = JSON.parse(blob);
+
+  const tilesets = new Map<number, TileSet>();
+  let loaded_tilesets = await Promise.all(
+    map.defs.tilesets
+      .filter((def: any) => def.relPath != null)
+      .map((def: any) => load_tileset(def))
+  );
+  for (const ts of loaded_tilesets) {
+    tilesets.set(ts.id, ts);
+  }
+
+  const levels = map.levels.map((l: any) => load_level(tilesets, l));
+  return { levels, tilesets };
+}
+
+export function draw_level(
+  level: Level,
+  offset_x: number = 0,
+  offset_y: number = 0
+) {
+  for (const layer of level.layers) {
+    use_texture(layer.texture);
+
+    let [ofx, ofy] = layer.offset;
+    ofx += offset_x;
+    ofy += offset_y;
+    for (const tile of layer.tiles) {
+      // TODO: Flip and whatnot.
+      spr(
+        tile.px[0] + ofx,
+        tile.px[1] + ofy,
+        layer.grid_size,
+        layer.grid_size,
+        tile.src[0],
+        tile.src[1]
+      );
+    }
+  }
+}

game/main.ts

@@ -2,8 +2,8 @@ import { cls, print, spr, use_texture, Texture } from "./graphics";
 import { load_texture } from "./assets";
 import { since_start } from "./time";
 import { btn, Button } from "./input";
-// import { load_string } from "./io";
 import { new_v2, vadd, vmul, vnorm } from "./vector";
+import { load_world, World, Level, draw_level } from "./level";
 
 /// TODO: Support reload by saving and restoring state from init/update/restore.
 
@@ -11,6 +11,8 @@ import { new_v2, vadd, vmul, vnorm } from "./vector";
 let clock = 0;
 
 let bot_sprite: Texture | undefined = undefined;
+let world: World | undefined = undefined;
+let level: Level | undefined = undefined;
 
 // Note zelda overworld is 16x8 screens
 //      zelda screen is 16x11 tiles
@@ -18,13 +20,6 @@ let bot_sprite: Texture | undefined = undefined;
 
 let loaded = false;
 
-async function load_map(path: string) {
-  // print("Loading map:", path);
-  // const blob = await load_string(path);
-  // const map = JSON.parse(blob);
-  // print("Loaded map:", map);
-}
-
 function load_assets() {
   // Start this load, but then...
   let texture_load = load_texture("./bot.png").then((n) => {
@@ -32,7 +27,16 @@ function load_assets() {
     bot_sprite = n;
   });
 
-  let map_load = load_map("./overworld.ldtk");
+  let map_load = load_world("./overworld.ldtk").then((w) => {
+    print("World loaded at", since_start());
+    world = w;
+
+    // Assume we start at 0,0
+    level = world.levels.find((l) => l.world_x == 0 && l.world_y == 0);
+    if (!level) {
+      throw new Error("UNABLE TO FIND LEVEL AT 0,0: CANNOT START");
+    }
+  });
 
   Promise.all([texture_load, map_load]).then(() => {
     loaded = true;
@@ -106,6 +110,10 @@ export function draw() {
     return;
   }
 
+  if (level != undefined) {
+    draw_level(level, 0, 0);
+  }
+
   if (bot_sprite != undefined) {
     // ...it gets resolved here?
     use_texture(bot_sprite);

src/lib.rs

@@ -58,39 +58,30 @@ impl ScreenUniforms {
     }
 }
 
-struct State {
-    surface: wgpu::Surface,
-    device: wgpu::Device,
-    queue: wgpu::Queue,
-    config: wgpu::SurfaceConfiguration,
-    size: winit::dpi::PhysicalSize<u32>,
-    window: Window,
-    render_pipeline: wgpu::RenderPipeline,
-
-    vertex_buffer: wgpu::Buffer,
+#[derive(Debug)]
+struct VertexBuffer {
+    buffer: wgpu::Buffer,
+    vec: Vec<Vertex>,
     max_vertices: usize,
-
-    sprite_bind_group_layout: wgpu::BindGroupLayout,
-    sprite_textures: HashMap<u32, wgpu::BindGroup>,
-
-    write_textures: HashMap<u32, texture::Texture>,
-
-    screen_uniform: ScreenUniforms,
-    screen_uniform_buffer: wgpu::Buffer,
-    screen_uniform_bind_group: wgpu::BindGroup,
-
-    // Garbage
-    mouse_x: f64,
-    mouse_y: f64,
 }
 
-// TUTORIAL FOR BABIES LIKE ME: https://sotrh.github.io/learn-wgpu/beginner/tutorial2-surface/
+#[derive(Clone, Debug)]
+struct VertexBufferHandle {
+    index: usize,
+    capacity: usize,
+}
 
-impl State {
-    // Creating some of the wgpu types requires async code
+struct WindowAndDevice {
+    pub window: Window,
+    // pub instance: wgpu::Instance,
+    pub surface: wgpu::Surface,
+    pub adapter: wgpu::Adapter,
+    pub device: wgpu::Device,
+    pub queue: wgpu::Queue,
+}
+
+impl WindowAndDevice {
     async fn new(window: Window) -> Self {
-        let size = window.inner_size();
-
         // The instance is a handle to our GPU
         // Backends::all => Vulkan + Metal + DX12 + Browser WebGPU
         let instance = wgpu::Instance::new(wgpu::InstanceDescriptor {
@@ -131,7 +122,52 @@ impl State {
             .await
             .unwrap();
 
-        let surface_caps = surface.get_capabilities(&adapter);
+        WindowAndDevice {
+            window,
+            surface,
+            adapter,
+            device,
+            queue,
+        }
+    }
+}
+
+struct State {
+    surface: wgpu::Surface,
+    device: wgpu::Device,
+    queue: wgpu::Queue,
+    config: wgpu::SurfaceConfiguration,
+    size: winit::dpi::PhysicalSize<u32>,
+    window: Window,
+    render_pipeline: wgpu::RenderPipeline,
+
+    vertex_buffers: Vec<VertexBuffer>,
+    next_free_vertex_buffer: usize,
+
+    sprite_bind_group_layout: wgpu::BindGroupLayout,
+    sprite_textures: HashMap<u32, wgpu::BindGroup>,
+
+    write_textures: HashMap<u32, texture::Texture>,
+
+    screen_uniform: ScreenUniforms,
+    screen_uniform_buffer: wgpu::Buffer,
+    screen_uniform_bind_group: wgpu::BindGroup,
+
+    // Garbage
+    mouse_x: f64,
+    mouse_y: f64,
+}
+
+// TUTORIAL FOR BABIES LIKE ME: https://sotrh.github.io/learn-wgpu/beginner/tutorial2-surface/
+
+impl State {
+    // Creating some of the wgpu types requires async code
+    fn new(hardware: WindowAndDevice) -> Self {
+        let size = hardware.window.inner_size();
+
+        let device = hardware.device;
+
+        let surface_caps = hardware.surface.get_capabilities(&hardware.adapter);
 
         // Shader code in this tutorial assumes an sRGB surface
         // texture. Using a different one will result all the colors coming
@@ -152,7 +188,7 @@ impl State {
             alpha_mode: surface_caps.alpha_modes[0],
             view_formats: vec![],
         };
-        surface.configure(&device, &config);
+        hardware.surface.configure(&device, &config);
 
         let sprite_bind_group_layout =
             device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
@@ -260,26 +296,17 @@ impl State {
             multiview: None,
         });
 
-        let max_vertices: usize = 4096;
-        let vertex_buffer = device.create_buffer(&wgpu::BufferDescriptor {
-            label: Some("Vertex Buffer"),
-            size: (max_vertices * std::mem::size_of::<Vertex>())
-                .try_into()
-                .unwrap(),
-            mapped_at_creation: false,
-            usage: wgpu::BufferUsages::VERTEX | wgpu::BufferUsages::COPY_DST,
-        });
-
         Self {
-            window,
-            surface,
+            window: hardware.window,
+            surface: hardware.surface,
             device,
-            queue,
+            queue: hardware.queue,
             config,
             size,
             render_pipeline: sprite_pipeline,
-            vertex_buffer,
-            max_vertices,
+            vertex_buffers: Vec::new(),
+            next_free_vertex_buffer: 0,
+
             sprite_bind_group_layout,
             sprite_textures: HashMap::new(),
             write_textures: HashMap::new(),
@@ -316,42 +343,30 @@ impl State {
 
     fn render(&mut self, commands: Vec<GraphicsCommand>) -> Result<(), wgpu::SurfaceError> {
         let _span = span!("context render");
-        let output = self.surface.get_current_texture()?;
 
-        // Group the commands into passes.
-        let screen_view = Rc::new(
-            output
-                .texture
-                .create_view(&wgpu::TextureViewDescriptor::default()),
-        );
-        let mut last_view = screen_view.clone();
+        // Reset vertex buffers.
+        self.next_free_vertex_buffer = 0;
 
-        struct Pass {
-            color: Option<[f64; 4]>,
-            commands: Vec<GraphicsCommand>,
-            target: Rc<wgpu::TextureView>,
-        }
-        let mut passes = Vec::new();
+        let mut builder = FrameBuilder::new(self)?;
         for command in commands {
-            match command {
-                GraphicsCommand::Clear(cc) => passes.push(Pass {
-                    color: Some(cc.color),
-                    commands: Vec::new(),
-                    target: last_view.clone(),
-                }),
+            builder.handle_command(command);
+        }
+        FrameBuilder::complete(builder);
 
-                GraphicsCommand::CreateTexture(ct) => {
+        Ok(())
+    }
+
+    fn create_texture(&mut self, id: u32, image: image::DynamicImage, label: Option<String>) {
         let texture = texture::Texture::from_image(
             &self.device,
             &self.queue,
-                        &ct.image,
-                        match &ct.label {
+            &image,
+            match &label {
                 Some(l) => Some(&l),
                 None => None,
             },
         );
-                    let sprite_bind_group =
-                        self.device.create_bind_group(&wgpu::BindGroupDescriptor {
+        let sprite_bind_group = self.device.create_bind_group(&wgpu::BindGroupDescriptor {
             layout: &self.sprite_bind_group_layout,
             entries: &[
                 wgpu::BindGroupEntry {
@@ -363,21 +378,22 @@ impl State {
                     resource: wgpu::BindingResource::Sampler(&texture.sampler),
                 },
             ],
-                            label: match &ct.label {
+            label: match &label {
                 Some(l) => Some(&l),
                 None => None,
             },
         });
 
-                    self.sprite_textures.insert(ct.id, sprite_bind_group);
+        self.sprite_textures.insert(id, sprite_bind_group);
     }
 
-                GraphicsCommand::CreateWritableTexture {
-                    id,
-                    width,
-                    height,
-                    label,
-                } => {
+    fn create_writeable_texture(
+        &mut self,
+        id: u32,
+        width: u32,
+        height: u32,
+        label: Option<String>,
+    ) {
         let texture = texture::Texture::new_writable(
             &self.device,
             width,
@@ -387,8 +403,7 @@ impl State {
                 None => None,
             },
         );
-                    let sprite_bind_group =
-                        self.device.create_bind_group(&wgpu::BindGroupDescriptor {
+        let sprite_bind_group = self.device.create_bind_group(&wgpu::BindGroupDescriptor {
             layout: &self.sprite_bind_group_layout,
             entries: &[
                 wgpu::BindGroupEntry {
@@ -410,80 +425,307 @@ impl State {
         self.write_textures.insert(id, texture);
     }
 
-                GraphicsCommand::WriteToTexture(id) => {
-                    let texture = self.write_textures.get(&id).unwrap();
-                    last_view = Rc::new(
-                        texture
-                            .texture
-                            .create_view(&wgpu::TextureViewDescriptor::default()),
-                    );
-                    let new_pass = match passes.last_mut() {
-                        Some(pass) => {
-                            if pass.commands.is_empty() {
-                                pass.target = last_view.clone();
-                                false
+    fn new_vertex_buffer(&mut self) -> VertexBufferHandle {
+        if self.next_free_vertex_buffer >= self.vertex_buffers.len() {
+            let max_vertices: usize = 4096;
+            let buffer = self.device.create_buffer(&wgpu::BufferDescriptor {
+                label: Some("Vertex Buffer"),
+                size: (max_vertices * std::mem::size_of::<Vertex>())
+                    .try_into()
+                    .unwrap(),
+                mapped_at_creation: false,
+                usage: wgpu::BufferUsages::VERTEX | wgpu::BufferUsages::COPY_DST,
+            });
+            self.vertex_buffers.push(VertexBuffer {
+                buffer,
+                max_vertices,
+                vec: Vec::with_capacity(max_vertices),
+            });
+        }
+
+        let index = self.next_free_vertex_buffer;
+        self.next_free_vertex_buffer += 1;
+        let vb = &mut self.vertex_buffers[index];
+        vb.vec.clear();
+        VertexBufferHandle {
+            index,
+            capacity: vb.max_vertices,
+        }
+    }
+
+    fn get_vertex_buffer(&self, handle: &VertexBufferHandle) -> &VertexBuffer {
+        &self.vertex_buffers[handle.index]
+    }
+
+    fn get_vertex_buffer_mut(&mut self, handle: &VertexBufferHandle) -> &mut VertexBuffer {
+        &mut self.vertex_buffers[handle.index]
+    }
+
+    fn copy_vertex_buffers(&mut self) {
+        for i in 0..self.next_free_vertex_buffer {
+            let vb = &self.vertex_buffers[i];
+            self.queue
+                .write_buffer(&vb.buffer, 0, bytemuck::cast_slice(&vb.vec));
+        }
+    }
+}
+
+#[derive(Debug)]
+struct DrawCall {
+    texture_id: Option<u32>,
+    vertex_buffer: VertexBufferHandle,
+    draw_start: u32,
+    draw_end: u32,
+}
+
+impl DrawCall {
+    pub fn new(vertex_buffer: VertexBufferHandle, draw_start: u32) -> Self {
+        DrawCall {
+            texture_id: None,
+            vertex_buffer,
+            draw_start,
+            draw_end: draw_start,
+        }
+    }
+
+    pub fn new_at_buffer_tail(&self) -> Self {
+        DrawCall::new(self.vertex_buffer.clone(), self.draw_end)
+    }
+
+    pub fn switch_textures(&self, id: u32) -> DrawCall {
+        let mut next = self.new_at_buffer_tail();
+        next.texture_id = Some(id);
+        next
+    }
+
+    pub fn empty(&self) -> bool {
+        self.draw_start == self.draw_end
+    }
+
+    pub fn allocate_capacity(&mut self, capacity: u32) -> Option<VertexBufferHandle> {
+        if self.vertex_buffer.capacity >= (self.draw_end + capacity) as usize {
+            self.draw_end += capacity;
+            Some(self.vertex_buffer.clone())
         } else {
-                                true
-                            }
-                        }
-                        None => true,
-                    };
-                    if new_pass {
-                        passes.push(Pass {
-                            color: None,
-                            commands: vec![],
-                            target: last_view.clone(),
-                        })
+            None
         }
     }
 
-                GraphicsCommand::WriteToScreen => {
-                    if !Rc::ptr_eq(&last_view, &screen_view) {
-                        // If I have a pass already I need a new one.
-                        last_view = screen_view.clone();
-                        if !passes.is_empty() {
-                            passes.push(Pass {
-                                color: None,
-                                commands: vec![],
-                                target: last_view.clone(),
-                            })
-                        }
-                    }
+    // pub fn draw<'a>(&'a self, pass: &'a mut wgpu::RenderPass, state: &'a State) {
+    //     if self.draw_start == self.draw_end {
+    //         return;
+    //     }
+
+    //     let texture_id = match self.texture_id {
+    //         Some(id) => id,
+    //         None => return,
+    //     };
+
+    //     let bind_group = state.sprite_textures.get(&texture_id).unwrap();
+    //     pass.set_bind_group(0, bind_group, &[]);
+
+    //     let vb = self.vertex_buffer.borrow();
+    //     pass.set_bind_group(1, &state.screen_uniform_bind_group, &[]);
+    //     pass.set_vertex_buffer(0, vb.buffer.slice(..));
+    //     pass.draw(self.draw_start..self.draw_end, 0..1);
+    // }
 }
 
-                GraphicsCommand::EndFrame => (),
-                other => match passes.last_mut() {
-                    Some(pass) => pass.commands.push(other),
-                    None => passes.push(Pass {
-                        color: None,
-                        commands: vec![other],
-                        target: last_view.clone(),
-                    }),
-                },
-            }
+struct FrameBuilder<'a> {
+    state: &'a mut State,
+    screen_view: Rc<wgpu::TextureView>,
+    last_view: Rc<wgpu::TextureView>,
+    encoder: wgpu::CommandEncoder,
+    output: wgpu::SurfaceTexture,
+
+    target: Rc<wgpu::TextureView>,
+    color: Option<[f64; 4]>,
+    draw_calls: Vec<DrawCall>,
 }
 
-        let mut vertices = Vec::new();
-        for pass in passes {
-            // TODO: It would be great if we could use multiple passes in a
-            //       single encoder but right now because of the dyanmic
-            //       nature of vertices we can't, I think? Because
-            //       queue.write_buffer doesn't actually happen until we call
-            //       submit...
-            let mut encoder = self
+impl<'a> FrameBuilder<'a> {
+    fn new(state: &'a mut State) -> Result<Self, wgpu::SurfaceError> {
+        let encoder = state
             .device
             .create_command_encoder(&wgpu::CommandEncoderDescriptor {
                 label: Some("Render Encoder"),
             });
 
-            {
-                let mut render_pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
+        let output = state.surface.get_current_texture()?;
+
+        let screen_view = Rc::new(
+            output
+                .texture
+                .create_view(&wgpu::TextureViewDescriptor::default()),
+        );
+        let last_view = screen_view.clone();
+
+        Ok(FrameBuilder {
+            state,
+            screen_view,
+            last_view: last_view.clone(),
+            encoder,
+            output,
+
+            target: last_view,
+            color: None,
+            draw_calls: Vec::new(),
+        })
+    }
+
+    fn complete(builder: FrameBuilder<'a>) {
+        let mut builder = builder;
+        builder.flush();
+
+        // At this point the state needs to copy the vertex buffers we know about.
+        builder.state.copy_vertex_buffers();
+
+        // Submit will accept anything that implements IntoIter
+        builder
+            .state
+            .queue
+            .submit(std::iter::once(builder.encoder.finish()));
+
+        builder.output.present();
+    }
+
+    fn handle_command(&mut self, command: GraphicsCommand) {
+        match command {
+            // ================================================================
+            // Pass commands
+            // ================================================================
+            // NOTE: You would expect a "change target" command to be
+            //       followed nearly immediately by a clear command and we
+            //       wind up starting an extra pass in that case which sucks.
+            GraphicsCommand::Clear(cc) => self.start_pass(Some(cc.color), self.last_view.clone()),
+            GraphicsCommand::WriteToTexture(id) => {
+                let texture = self.state.write_textures.get(&id).unwrap();
+                self.last_view = Rc::new(
+                    texture
+                        .texture
+                        .create_view(&wgpu::TextureViewDescriptor::default()),
+                );
+                self.start_pass(None, self.last_view.clone());
+            }
+            GraphicsCommand::WriteToScreen => {
+                if !Rc::ptr_eq(&self.last_view, &self.screen_view) {
+                    self.last_view = self.screen_view.clone();
+                    self.start_pass(None, self.last_view.clone());
+                }
+            }
+            GraphicsCommand::Print(pc) => println!("{}", pc.text),
+            GraphicsCommand::Sprite(sc) => self.push_sprite(sc),
+            GraphicsCommand::UseTexture(id) => self.use_texture(id),
+            GraphicsCommand::EndFrame => self.flush(),
+
+            // ================================================================
+            // Resource commands
+            // ================================================================
+            GraphicsCommand::CreateTexture(ct) => {
+                self.state.create_texture(ct.id, ct.image, ct.label)
+            }
+            GraphicsCommand::CreateWritableTexture {
+                id,
+                width,
+                height,
+                label,
+            } => self
+                .state
+                .create_writeable_texture(id, width, height, label),
+        }
+    }
+
+    fn start_pass(&mut self, color: Option<[f64; 4]>, target: Rc<wgpu::TextureView>) {
+        self.flush();
+        self.color = color;
+        self.target = target;
+    }
+
+    fn use_texture(&mut self, texture_id: u32) {
+        match self.draw_calls.last_mut() {
+            Some(call) => match call.texture_id {
+                Some(id) => {
+                    if id == texture_id {
+                        return;
+                    } else if call.empty() {
+                        call.texture_id = Some(texture_id);
+                    } else {
+                        let next = call.switch_textures(texture_id);
+                        self.draw_calls.push(next);
+                        return;
+                    }
+                }
+                None => {
+                    call.texture_id = Some(texture_id);
+                }
+            },
+            None => {
+                let mut call = DrawCall::new(self.state.new_vertex_buffer(), 0);
+                call.texture_id = Some(texture_id);
+                self.draw_calls.push(call);
+            }
+        }
+    }
+
+    fn get_vertex_buffer(&mut self, required_capacity: u32) -> &mut VertexBuffer {
+        match self.draw_calls.last_mut() {
+            Some(call) => match call.allocate_capacity(required_capacity) {
+                Some(vb) => return self.state.get_vertex_buffer_mut(&vb),
+                None => {}
+            },
+            None => {}
+        };
+
+        let mut call = DrawCall::new(self.state.new_vertex_buffer(), 0);
+        let vb = call.allocate_capacity(required_capacity).unwrap();
+        self.draw_calls.push(call);
+        self.state.get_vertex_buffer_mut(&vb)
+    }
+
+    fn push_sprite(&mut self, sc: script::graphics::SpriteCommand) {
+        let vertex_buffer = self.get_vertex_buffer(6);
+
+        vertex_buffer.vec.push(Vertex {
+            position: [sc.x, sc.y, 0.0],
+            tex_coords: [sc.u, sc.v],
+        });
+        vertex_buffer.vec.push(Vertex {
+            position: [sc.x, sc.y + sc.h, 0.0],
+            tex_coords: [sc.u, sc.v + sc.sh],
+        });
+        vertex_buffer.vec.push(Vertex {
+            position: [sc.x + sc.w, sc.y, 0.0],
+            tex_coords: [sc.u + sc.sw, sc.v],
+        });
+
+        vertex_buffer.vec.push(Vertex {
+            position: [sc.x, sc.y + sc.h, 0.0],
+            tex_coords: [sc.u, sc.v + sc.sh],
+        });
+        vertex_buffer.vec.push(Vertex {
+            position: [sc.x + sc.w, sc.y + sc.h, 0.0],
+            tex_coords: [sc.u + sc.sw, sc.v + sc.sh],
+        });
+        vertex_buffer.vec.push(Vertex {
+            position: [sc.x + sc.w, sc.y, 0.0],
+            tex_coords: [sc.u + sc.sw, sc.v],
+        });
+    }
+
+    fn flush(&mut self) {
+        let first_call = match self.draw_calls.last() {
+            Some(call) => call.new_at_buffer_tail(),
+            None => DrawCall::new(self.state.new_vertex_buffer(), 0),
+        };
+
+        if self.draw_calls.len() > 0 {
+            let mut pass = self.encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
                 label: Some("Render Pass"),
                 color_attachments: &[Some(wgpu::RenderPassColorAttachment {
-                        view: &pass.target,
+                    view: &self.target,
                     resolve_target: None,
                     ops: wgpu::Operations {
-                            load: if let Some([r, g, b, a]) = pass.color {
+                        load: if let Some([r, g, b, a]) = self.color {
                             wgpu::LoadOp::Clear(wgpu::Color {
                                 r, //0.1,
                                 g, //0.2,
@@ -499,77 +741,32 @@ impl State {
                 depth_stencil_attachment: None,
             });
 
-                let mut texture_id = None;
-                vertices.clear();
-                for command in pass.commands {
-                    match command {
-                        GraphicsCommand::Print(pc) => {
-                            println!("{}", pc.text);
-                        }
-                        GraphicsCommand::Sprite(sc) => {
-                            vertices.push(Vertex {
-                                position: [sc.x, sc.y, 0.0],
-                                tex_coords: [sc.u, sc.v],
-                            });
-                            vertices.push(Vertex {
-                                position: [sc.x, sc.y + sc.h, 0.0],
-                                tex_coords: [sc.u, sc.v + sc.sh],
-                            });
-                            vertices.push(Vertex {
-                                position: [sc.x + sc.w, sc.y, 0.0],
-                                tex_coords: [sc.u + sc.sw, sc.v],
-                            });
-
-                            vertices.push(Vertex {
-                                position: [sc.x, sc.y + sc.h, 0.0],
-                                tex_coords: [sc.u, sc.v + sc.sh],
-                            });
-                            vertices.push(Vertex {
-                                position: [sc.x + sc.w, sc.y + sc.h, 0.0],
-                                tex_coords: [sc.u + sc.sw, sc.v + sc.sh],
-                            });
-                            vertices.push(Vertex {
-                                position: [sc.x + sc.w, sc.y, 0.0],
-                                tex_coords: [sc.u + sc.sw, sc.v],
-                            });
+            pass.set_pipeline(&self.state.render_pipeline);
+            for call in &self.draw_calls {
+                if call.draw_start == call.draw_end {
+                    continue;
                 }
 
-                        GraphicsCommand::UseTexture(id) => texture_id = Some(id),
+                let texture_id = match call.texture_id {
+                    Some(id) => id,
+                    None => return,
+                };
 
-                        GraphicsCommand::CreateTexture(_) => (), // Already handled
-                        GraphicsCommand::CreateWritableTexture { .. } => (), // Already handled
-                        GraphicsCommand::WriteToTexture(_) => (), // Already handled
-                        GraphicsCommand::WriteToScreen => (),    // Already handled
-                        GraphicsCommand::Clear(_) => (),         // Already handled
-                        GraphicsCommand::EndFrame => (),         // Should never appear
+                let bind_group = self.state.sprite_textures.get(&texture_id).unwrap();
+                pass.set_bind_group(0, bind_group, &[]);
+
+                let vb = self.state.get_vertex_buffer(&call.vertex_buffer);
+                pass.set_bind_group(1, &self.state.screen_uniform_bind_group, &[]);
+                pass.set_vertex_buffer(0, vb.buffer.slice(..));
+                pass.draw(call.draw_start..call.draw_end, 0..1);
+
+                // call.draw(&mut pass, &self.state);
             }
         }
 
-                if let Some(id) = texture_id {
-                    assert!(vertices.len() < self.max_vertices); // !
-                    self.queue.write_buffer(
-                        &self.vertex_buffer,
-                        0,
-                        bytemuck::cast_slice(&vertices),
-                    );
-                    render_pass.set_pipeline(&self.render_pipeline);
-
-                    let bind_group = self.sprite_textures.get(&id).unwrap();
-                    render_pass.set_bind_group(0, bind_group, &[]);
-
-                    render_pass.set_bind_group(1, &self.screen_uniform_bind_group, &[]);
-                    render_pass.set_vertex_buffer(0, self.vertex_buffer.slice(..));
-                    render_pass.draw(0..(vertices.len() as u32), 0..1);
-                }
-            }
-
-            // Submit will accept anything that implements IntoIter
-            self.queue.submit(std::iter::once(encoder.finish()));
-        }
-
-        output.present();
-
-        Ok(())
+        self.color = None;
+        self.draw_calls.clear();
+        self.draw_calls.push(first_call);
     }
 }
 
@@ -670,11 +867,12 @@ pub async fn run() {
     let window = WindowBuilder::new().build(&event_loop).unwrap();
     let event_loop_proxy = event_loop.create_proxy();
 
-    let state = State::new(window).await;
+    let hardware = WindowAndDevice::new(window).await;
     let (sender, reciever) = std::sync::mpsc::channel();
 
     std::thread::spawn(move || {
         set_thread_name!("game thread");
+        let state = State::new(hardware);
         main_thread(event_loop_proxy, state, reciever);
     });