Render: node renders follow the anti-aliasing option

render_node_with and render_node_thumbnail_with drew into a new context
without setting its aliasing threshold, so AntiAlias::None still gave
smooth edges. Both now set the threshold from the options, as a page
render does.

crates/render/src/renderer.rs

@@ -321,6 +321,7 @@ impl Renderer {
         let visible = inv.transform_rect_bbox(Rect::new(0.0, 0.0, w as f64, h as f64));
         let px = 1.0 / view.determinant().abs().sqrt().max(1e-12);
         let mut ctx = single_threaded_context(w, h);
+        ctx.set_aliasing_threshold(opts.anti_alias.threshold());
         let symbols = doc.symbol_boxes().quick();
         let frame = Frame { mt: false, doc, symbols: &symbols, view, visible, px, opts, ink: Ink::Display, plates: None };
         self.begin_frame();
@@ -361,6 +362,7 @@ impl Renderer {
         let s = (w as f64 - 2.0).max(1.0) / b.width().max(b.height()).max(1e-6);
         let view = Affine::translate((w as f64 / 2.0, w as f64 / 2.0)) * Affine::scale(s) * Affine::translate(-b.center().to_vec2());
         let mut ctx = single_threaded_context(w, w);
+        ctx.set_aliasing_threshold(opts.anti_alias.threshold());
         if let Some(bg) = background {
             ctx.set_paint(peniko::Color::from_rgba8(bg[0], bg[1], bg[2], bg[3]));
             ctx.fill_rect(&kurbo::Rect::new(0.0, 0.0, w as f64, w as f64));

crates/render/src/tests.rs

@@ -886,6 +886,25 @@ fn node_thumbnail_reports_the_size_it_draws() {
     }
 }
 
+/// A node rendered with `AntiAlias::None` has hard edges, as a page render with that option does.
+#[test]
+fn node_renders_follow_the_anti_alias_option() {
+    let mut d = Document::new(100.0, 100.0);
+    let id = d.alloc_id();
+    let n = Node::path(id, shapes::ellipse(Rect::new(10.3, 10.3, 60.6, 60.6)), Appearance::basic(Paint::solid(Color::BLACK), Paint::None, 0.0));
+    let node = Arc::new(n.clone());
+    let hard = RenderOptions { anti_alias: AntiAlias::None, ..Default::default() };
+    let partial = |img: &Rendered| img.pixels.chunks(4).any(|p| p[3] != 0 && p[3] != 255);
+    let drawn = |img: &Rendered| img.pixels.chunks(4).any(|p| p[3] == 255);
+    let mut r = Renderer::new();
+    assert!(partial(&r.render_node(&d, &node, 100, 100, Affine::IDENTITY).unwrap()), "art anti-aliasing has partial edge pixels");
+    assert!(partial(&r.render_node_thumbnail(&d, &n, 37, None).unwrap()), "art anti-aliasing has partial edge pixels");
+    let img = r.render_node_with(&d, &node, 100, 100, Affine::IDENTITY, &hard).unwrap();
+    assert!(drawn(&img) && !partial(&img), "render_node_with: every alpha is 0 or 255");
+    let thumb = r.render_node_thumbnail_with(&d, &n, 37, None, &hard).unwrap();
+    assert!(drawn(&thumb) && !partial(&thumb), "render_node_thumbnail_with: every alpha is 0 or 255");
+}
+
 #[test]
 fn opacity_mask_with_undecodable_image_leaves_out_object() {
     use vectorcraft_doc::{Effect, ImageBlob, ImageObject, NodeKind, OpacityMask};