Add headless multi-layer symbol rendering example using Vello Classic

Cargo.toml

@@ -12,6 +12,7 @@ members = [
     "examples/scenes",
     "examples/simple",
     "examples/with_winit",
+    "examples/symbols",
 
     "sparse_strips/vello_api",
     "sparse_strips/vello_bench",

examples/symbols/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "symbols"
+version = "0.1.0"
+description = "An example rendering layered point, line, and polygon symbols with Vello."
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+readme = "README.md"
+keywords = ["symbol", "rendering", "graphics"]
+categories = ["graphics", "visualization", "rendering"]
+
+[lints]
+workspace = true
+
+[dependencies]
+vello = { workspace = true }
+
+anyhow = { workspace = true }
+clap = { workspace = true, features = ["derive"] }
+
+pollster = { workspace = true }
+env_logger = "0.11"
+png = { workspace = true }
+futures-intrusive = { workspace = true }

examples/symbols/README.md

@@ -0,0 +1,31 @@
+# symbols
+
+Headless symbol rendering example built on top of Vello Classic.
+
+This crate demonstrates how to use a rendering pipeline to generate high-quality 2D map-like graphics, including polygons, roads, water layers, and point symbols, and export the result as a PNG image.
+
+It is designed as an example of integrating vector-style rendering with a GPU backend using `wgpu`.
+
+---
+
+## Features
+
+- Headless (offscreen) rendering using GPU
+- Map-style layered rendering:
+    - Polygon landuse layers
+    - Water and river rendering
+    - Cased road rendering
+    - Grid overlay
+    - Point symbols with multi-layer styling
+- Gradient fills, strokes, and clipping support
+- Export rendered result to PNG
+- Configurable antialiasing (MSAA / area)
+- Optional CPU rendering mode
+
+---
+
+## Usage
+```bash
+cargo run -p symbols
+cargo run -p symbols -- --width 1600 --height 900 --aa msaa16 --output output.png
+```