Support setting AA method dynamically

examples/headless/src/main.rs

@@ -87,10 +87,11 @@ async fn render(mut scenes: SceneSet, index: usize, args: &Args) -> Result<()> {
     let queue = &device_handle.queue;
     let mut renderer = vello::Renderer::new(
         device,
-        &RendererOptions {
+        RendererOptions {
             surface_format: None,
             timestamp_period: queue.get_timestamp_period(),
             use_cpu: false,
+            antialiasing_support: vello::AaSupport::area_only(),
         },
     )
     .or_else(|_| bail!("Got non-Send/Sync error from creating renderer"))?;
@@ -140,6 +141,7 @@ async fn render(mut scenes: SceneSet, index: usize, args: &Args) -> Result<()> {
             .unwrap_or(vello::peniko::Color::BLACK),
         width,
         height,
+        antialiasing_method: vello::AaConfig::Area,
     };
     let mut scene = Scene::new();
     let mut builder = SceneBuilder::for_scene(&mut scene);

examples/scenes/src/test_scenes.rs

@@ -1246,10 +1246,11 @@ fn splash_screen(sb: &mut SceneBuilder, params: &mut SceneParams) {
         "  Space: reset transform",
         "  S: toggle stats",
         "  V: toggle vsync",
+        "  M: cycle AA method",
         "  Q, E: rotate",
     ];
     // Tweak to make it fit with tiger
-    let a = Affine::scale(0.12) * Affine::translate((-90.0, -50.0));
+    let a = Affine::scale(0.11) * Affine::translate((-90.0, -50.0));
     for (i, s) in strings.iter().enumerate() {
         let text_size = if i == 0 { 60.0 } else { 40.0 };
         params.text.add(

examples/with_bevy/src/main.rs

@@ -30,6 +30,7 @@ impl FromWorld for VelloRenderer {
                 &RendererOptions {
                     surface_format: None,
                     timestamp_period: queue.0.get_timestamp_period(),
+                    antialiasing_support: vello::AaSupport::area_only(),
                 },
             )
             .unwrap(),
@@ -65,6 +66,7 @@ fn render_scenes(
             base_color: vello::peniko::Color::AQUAMARINE,
             width: gpu_image.size.x as u32,
             height: gpu_image.size.y as u32,
+            antialiasing_method: vello::AaConfig::Area,
         };
         renderer
             .0

examples/with_winit/src/lib.rs

@@ -25,7 +25,7 @@ use vello::util::RenderSurface;
 use vello::{
     kurbo::{Affine, Vec2},
     util::RenderContext,
-    Renderer, Scene, SceneBuilder,
+    AaConfig, Renderer, Scene, SceneBuilder,
 };
 use vello::{BumpAllocators, RendererOptions, SceneFragment};
 
@@ -85,10 +85,11 @@ fn run(
         renderers[id] = Some(
             Renderer::new(
                 &render_cx.devices[id].device,
-                &RendererOptions {
+                RendererOptions {
                     surface_format: Some(render_state.surface.format),
                     timestamp_period: render_cx.devices[id].queue.get_timestamp_period(),
                     use_cpu: use_cpu,
+                    antialiasing_support: vello::AaSupport::all(),
                 },
             )
             .expect("Could create renderer"),
@@ -111,6 +112,11 @@ fn run(
     let mut scene_complexity: Option<BumpAllocators> = None;
     let mut complexity_shown = false;
     let mut vsync_on = true;
+
+    const AA_CONFIGS: [AaConfig; 3] = [AaConfig::Area, AaConfig::Msaa8, AaConfig::Msaa16];
+    // We allow cycling through AA configs in either direction, so use a signed index
+    let mut aa_config_ix: i32 = 0;
+
     let mut frame_start_time = Instant::now();
     let start = Instant::now();
 
@@ -130,6 +136,7 @@ fn run(
     let mut profile_stored = None;
     let mut prev_scene_ix = scene_ix - 1;
     let mut profile_taken = Instant::now();
+    let mut modifiers = ModifiersState::default();
     // _event_loop is used on non-wasm platforms to create new windows
     event_loop.run(move |event, _event_loop, control_flow| match event {
         Event::WindowEvent {
@@ -144,6 +151,7 @@ fn run(
             }
             match event {
                 WindowEvent::CloseRequested => *control_flow = ControlFlow::Exit,
+                WindowEvent::ModifiersChanged(m) => modifiers = *m,
                 WindowEvent::KeyboardInput { input, .. } => {
                     if input.state == ElementState::Pressed {
                         match input.virtual_keycode {
@@ -173,6 +181,13 @@ fn run(
                             Some(VirtualKeyCode::C) => {
                                 stats.clear_min_and_max();
                             }
+                            Some(VirtualKeyCode::M) => {
+                                aa_config_ix = if modifiers.shift() {
+                                    aa_config_ix.saturating_sub(1)
+                                } else {
+                                    aa_config_ix.saturating_add(1)
+                                };
+                            }
                             Some(VirtualKeyCode::P) => {
                                 if let Some(renderer) = &renderers[render_state.surface.dev_id] {
                                     if let Some(profile_result) = &renderer
@@ -324,6 +339,8 @@ fn run(
 
             // Allow looping forever
             scene_ix = scene_ix.rem_euclid(scenes.scenes.len() as i32);
+            aa_config_ix = aa_config_ix.rem_euclid(AA_CONFIGS.len() as i32);
+
             let example_scene = &mut scenes.scenes[scene_ix as usize];
             if prev_scene_ix != scene_ix {
                 transform = Affine::IDENTITY;
@@ -348,14 +365,17 @@ fn run(
 
             // If the user specifies a base color in the CLI we use that. Otherwise we use any
             // color specified by the scene. The default is black.
+            let base_color = args
+                .args
+                .base_color
+                .or(scene_params.base_color)
+                .unwrap_or(Color::BLACK);
+            let antialiasing_method = AA_CONFIGS[aa_config_ix as usize];
             let render_params = vello::RenderParams {
-                base_color: args
-                    .args
-                    .base_color
-                    .or(scene_params.base_color)
-                    .unwrap_or(Color::BLACK),
+                base_color,
                 width,
                 height,
+                antialiasing_method,
             };
             let mut builder = SceneBuilder::for_scene(&mut scene);
             let mut transform = transform;
@@ -376,6 +396,7 @@ fn run(
                     stats.samples(),
                     complexity_shown.then_some(scene_complexity).flatten(),
                     vsync_on,
+                    antialiasing_method,
                 );
                 if let Some(profiling_result) = renderers[render_state.surface.dev_id]
                     .as_mut()
@@ -492,12 +513,13 @@ fn run(
                         eprintln!("Creating renderer {id}");
                         Renderer::new(
                             &render_cx.devices[id].device,
-                            &RendererOptions {
+                            RendererOptions {
                                 surface_format: Some(render_state.surface.format),
                                 timestamp_period: render_cx.devices[id]
                                     .queue
                                     .get_timestamp_period(),
                                 use_cpu,
+                                antialiasing_support: vello::AaSupport::all(),
                             },
                         )
                         .expect("Could create renderer")

examples/with_winit/src/stats.rs

@@ -19,7 +19,7 @@ use std::{collections::VecDeque, time::Duration};
 use vello::{
     kurbo::{Affine, Line, PathEl, Rect, Stroke},
     peniko::{Brush, Color, Fill},
-    BumpAllocators, SceneBuilder,
+    AaConfig, BumpAllocators, SceneBuilder,
 };
 use wgpu_profiler::GpuTimerScopeResult;
 
@@ -44,6 +44,7 @@ impl Snapshot {
         samples: T,
         bump: Option<BumpAllocators>,
         vsync: bool,
+        aa_config: AaConfig,
     ) where
         T: Iterator<Item = &'a u64>,
     {
@@ -67,6 +68,14 @@ impl Snapshot {
             format!("Frame Time (min): {:.2} ms", self.frame_time_min_ms),
             format!("Frame Time (max): {:.2} ms", self.frame_time_max_ms),
             format!("VSync: {}", if vsync { "on" } else { "off" }),
+            format!(
+                "AA method: {}",
+                match aa_config {
+                    AaConfig::Area => "Analytic Area",
+                    AaConfig::Msaa16 => "16xMSAA",
+                    AaConfig::Msaa8 => "8xMSAA",
+                }
+            ),
             format!("Resolution: {viewport_width}x{viewport_height}"),
         ];
         if let Some(bump) = &bump {

src/lib.rs

@@ -62,22 +62,43 @@ pub type Error = Box<dyn std::error::Error>;
 /// Specialization of `Result` for our catch-all error type.
 pub type Result<T> = std::result::Result<T, Error>;
 
-/// Possible configurations for antialiasing.
-#[derive(PartialEq, Eq)]
-#[allow(unused)]
-enum AaConfig {
+/// Represents the antialiasing method to use during a render pass.
+#[derive(Copy, Clone, PartialEq, Eq)]
+pub enum AaConfig {
     Area,
     Msaa8,
     Msaa16,
 }
 
-/// Configuration of antialiasing. Currently this is static, but could be switched to
-/// a launch option or even finer-grained.
-const ANTIALIASING: AaConfig = AaConfig::Msaa16;
+/// Represents the set of antialiasing configurations to enable during pipeline creation.
+pub struct AaSupport {
+    pub area: bool,
+    pub msaa8: bool,
+    pub msaa16: bool,
+}
+
+impl AaSupport {
+    pub fn all() -> Self {
+        Self {
+            area: true,
+            msaa8: true,
+            msaa16: true,
+        }
+    }
+
+    pub fn area_only() -> Self {
+        Self {
+            area: true,
+            msaa8: false,
+            msaa16: false,
+        }
+    }
+}
 
 /// Renders a scene into a texture or surface.
 #[cfg(feature = "wgpu")]
 pub struct Renderer {
+    options: RendererOptions,
     engine: WgpuEngine,
     shaders: FullShaders,
     blit: Option<BlitPipeline>,
@@ -86,8 +107,6 @@ pub struct Renderer {
     profiler: GpuProfiler,
     #[cfg(feature = "wgpu-profiler")]
     pub profile_result: Option<Vec<wgpu_profiler::GpuTimerScopeResult>>,
-    #[cfg(feature = "hot_reload")]
-    use_cpu: bool,
 }
 
 /// Parameters used in a single render that are configurable by the client.
@@ -99,40 +118,54 @@ pub struct RenderParams {
     /// Dimensions of the rasterization target
     pub width: u32,
     pub height: u32,
+
+    /// The anti-aliasing algorithm. The selected algorithm must have been initialized while
+    /// constructing the `Renderer`.
+    pub antialiasing_method: AaConfig,
 }
 
 #[cfg(feature = "wgpu")]
 pub struct RendererOptions {
     /// The format of the texture used for surfaces with this renderer/device
     /// If None, the renderer cannot be used with surfaces
     pub surface_format: Option<TextureFormat>,
+
     /// The timestamp period from [`wgpu::Queue::get_timestamp_period`]
     /// Used when the wgpu-profiler feature is enabled
     pub timestamp_period: f32,
+
+    /// If true, run all stages up to fine rasterization on the CPU.
+    // TODO: Consider evolving this so that the CPU stages can be configured dynamically via
+    // `RenderParams`.
     pub use_cpu: bool,
+
+    /// Represents the enabled set of AA configurations. This will be used to determine which
+    /// pipeline permutations should be compiled at startup.
+    pub antialiasing_support: AaSupport,
 }
 
 #[cfg(feature = "wgpu")]
 impl Renderer {
     /// Creates a new renderer for the specified device.
-    pub fn new(device: &Device, render_options: &RendererOptions) -> Result<Self> {
-        let mut engine = WgpuEngine::new(render_options.use_cpu);
-        let shaders = shaders::full_shaders(device, &mut engine)?;
-        let blit = render_options
+    pub fn new(device: &Device, options: RendererOptions) -> Result<Self> {
+        let mut engine = WgpuEngine::new(options.use_cpu);
+        let shaders = shaders::full_shaders(device, &mut engine, &options)?;
+        let blit = options
             .surface_format
             .map(|surface_format| BlitPipeline::new(device, surface_format));
+        #[cfg(feature = "wgpu-profiler")]
+        let timestamp_period = options.timestamp_period;
         Ok(Self {
+            options,
             engine,
             shaders,
             blit,
             target: None,
             // Use 3 pending frames
             #[cfg(feature = "wgpu-profiler")]
-            profiler: GpuProfiler::new(3, render_options.timestamp_period, device.features()),
+            profiler: GpuProfiler::new(3, timestamp_period, device.features()),
             #[cfg(feature = "wgpu-profiler")]
             profile_result: None,
-            #[cfg(feature = "hot_reload")]
-            use_cpu: render_options.use_cpu,
         })
     }
 
@@ -237,8 +270,8 @@ impl Renderer {
     #[cfg(feature = "hot_reload")]
     pub async fn reload_shaders(&mut self, device: &Device) -> Result<()> {
         device.push_error_scope(wgpu::ErrorFilter::Validation);
-        let mut engine = WgpuEngine::new(self.use_cpu);
-        let shaders = shaders::full_shaders(device, &mut engine)?;
+        let mut engine = WgpuEngine::new(self.options.use_cpu);
+        let shaders = shaders::full_shaders(device, &mut engine, &self.options)?;
         let error = device.pop_error_scope().await;
         if let Some(error) = error {
             return Err(error.into());