diff --git a/crates/engine/presets/text_animators.json b/crates/engine/presets/text_animators.json index 20e142268..e82707a52 100644 --- a/crates/engine/presets/text_animators.json +++ b/crates/engine/presets/text_animators.json @@ -77,7 +77,7 @@ "name": "Tracking In", "properties": { "tracking": 0, "opacity": 100 }, "keys": { - "tracking": [[0, 400], [1.6, 0]], + "tracking": [[0, 40], [1.6, 0]], "opacity": [[0, 0], [0.8, 100]] }, "ease": true, diff --git a/crates/lottie/src/text.rs b/crates/lottie/src/text.rs index 125835c2b..e9de3d328 100644 --- a/crates/lottie/src/text.rs +++ b/crates/lottie/src/text.rs @@ -227,8 +227,8 @@ fn style_run_animators(ex: &mut Ex, d: &TextDoc, label: &str) -> Vec { props.insert("s".into(), k(json!([p, p, 100.0]))); } if (s.tracking - base.tracking).abs() > 1e-9 { - // Lottie tracking is in 1/1000 em like the Character panel's. - props.insert("t".into(), k(json!(s.tracking - base.tracking))); + // An animator's tracking is in pixels; the Character panel's in 1/1000 em. + props.insert("t".into(), k(json!((s.tracking - base.tracking) / 1000.0 * s.size))); } if (s.baseline_shift - base.baseline_shift).abs() > 1e-9 { props.insert("p".into(), k(json!([0.0, -(s.baseline_shift - base.baseline_shift), 0.0]))); diff --git a/crates/render/src/text.rs b/crates/render/src/text.rs index fbb0feb24..302f31162 100644 --- a/crates/render/src/text.rs +++ b/crates/render/src/text.rs @@ -639,10 +639,12 @@ pub fn text_geom(ctx: &EvalCtx, layer: &Layer) -> Option { let (mut la, mut la_k) = (50.0 * f64::from(align_index(justify)), 0.0); for gi in li_start..li_end { let x = &xfs[gi]; - let em = lay.styles.get(lay.glyphs[gi].run).map_or(doc.size, |s| s.size) / 1000.0; - pen += x.track_before * em; + // An animator's Tracking Amount is in pixels, whatever the font size (After Effects + // 2026: Amount 30 adds 30 px between selected characters at 80 px and at 40 px), unlike + // the Character panel's tracking in 1/1000 em. + pen += x.track_before; shift[gi] = pen; - pen += x.track_after * em + vadv[gi]; + pen += x.track_after + vadv[gi]; if x.line_anchor_k > la_k { la = x.line_anchor; la_k = x.line_anchor_k; diff --git a/crates/render/src/text/tests.rs b/crates/render/src/text/tests.rs index 020e08517..760bd2fff 100644 --- a/crates/render/src/text/tests.rs +++ b/crates/render/src/text/tests.rs @@ -202,9 +202,9 @@ fn tracking_line_anchor_and_character_offset() { animator(&mut p, &mut l, &["tracking", "lineAnchor"], &["range"]); p.comp_mut(cid).unwrap().layers.push(l); let w0 = bounds_of(&glyph_paths(&ctx(&p, cid, 0.0), &p.comp(cid).unwrap().layers[0])); - set(&mut p.comp_mut(cid).unwrap().layers[0], "text/animators/#1/properties/tracking", Value::Scalar(500.0)); + set(&mut p.comp_mut(cid).unwrap().layers[0], "text/animators/#1/properties/tracking", Value::Scalar(20.0)); let w1 = bounds_of(&glyph_paths(&ctx(&p, cid, 0.0), &p.comp(cid).unwrap().layers[0])); - // 4 chars × 500/1000 em × 40 px: the last glyph moves ~ 3.5 × 20 px further (before & after). + // Tracking Amount 20 (pixels, as After Effects): the last glyph moves ~ 3.5 × 20 px further (before & after). assert!((w1.width() - w0.width() - 3.0 * 20.0).abs() < 1.5, "{} {}", w0.width(), w1.width()); assert!((w1.x0 - w0.x0 - 10.0).abs() < 1.0, "first char shifts by half its tracking: {} {}", w0.x0, w1.x0); // Line Anchor 100%: tracking grows to the left. @@ -231,6 +231,29 @@ fn tracking_line_anchor_and_character_offset() { assert_eq!(substitute('a', &CharXf { char_value: Some((66.0, 1.0)), ..Default::default() }), Some('B')); } +/// After Effects 2026: a text animator's Tracking Amount is in pixels: Amount 30 on every +/// character of an 80 px and of a 40 px text adds 30 px between neighbouring characters (half +/// before, half after each one). +#[test] +fn animator_tracking_is_in_pixels_as_in_after_effects() { + for size in [80.0, 40.0] { + let x_of = |amount: f64| { + let (mut p, cid, comp) = setup(900, 200); + let mut l = text_layer(&mut p, &comp, doc("HHHH", size)); + animator(&mut p, &mut l, &["tracking"], &["range"]); + set(&mut l, "text/animators/#1/properties/tracking", Value::Scalar(amount)); + p.comp_mut(cid).unwrap().layers.push(l); + let paths = glyph_paths(&ctx(&p, cid, 0.0), &p.comp(cid).unwrap().layers[0]); + paths.iter().map(|g| bounds_of(std::slice::from_ref(g)).x0).collect::>() + }; + let (a, b) = (x_of(0.0), x_of(30.0)); + for i in 1..a.len() { + let gap = (b[i] - b[i - 1]) - (a[i] - a[i - 1]); + assert!((gap - 30.0).abs() < 0.5, "{size} px: neighbour gap grows by {gap}"); + } + } +} + /// Without a Line Anchor, tracking grows each line from where its paragraph's alignment pins it: /// left text grows right, centred text around its centre, right text to the left (#146). #[test] @@ -244,10 +267,10 @@ fn tracking_grows_from_each_paragraphs_alignment() { p.comp_mut(cid).unwrap().layers.push(l); glyph_paths(&ctx(&p, cid, 0.0), &p.comp(cid).unwrap().layers[0]) }; - // 4 chars × 500/1000 em × 40 px: 20 px of tracking each, half before and half after. + // Tracking Amount 20 (pixels): 20 px of tracking each, half before and half after. for (justify, x0, centre, x1) in [(Justify::Left, 10.0, 40.0, 70.0), (Justify::Center, -30.0, 0.0, 30.0), (Justify::Right, -70.0, -40.0, -10.0)] { let d = TextDoc { justify, ..doc("ABCD", 40.0) }; - let (w0, w1) = (bounds_of(&tracked(d.clone(), 0.0)), bounds_of(&tracked(d, 500.0))); + let (w0, w1) = (bounds_of(&tracked(d.clone(), 0.0)), bounds_of(&tracked(d, 20.0))); let got = [w1.x0 - w0.x0, w1.center().x - w0.center().x, w1.x1 - w0.x1]; assert!(got.iter().zip([x0, centre, x1]).all(|(g, w)| (g - w).abs() < 1.0), "{justify:?}: moved {got:?}, want {:?}", [x0, centre, x1]); } @@ -259,7 +282,7 @@ fn tracking_grows_from_each_paragraphs_alignment() { let (a, b): (Vec<_>, Vec<_>) = paths.into_iter().partition(|g| bounds_of(std::slice::from_ref(g)).center().y < 10.0); [bounds_of(&a), bounds_of(&b)] }; - let ([a0, b0], [a1, b1]) = (lines(tracked(d.clone(), 0.0)), lines(tracked(d, 500.0))); + let ([a0, b0], [a1, b1]) = (lines(tracked(d.clone(), 0.0)), lines(tracked(d, 20.0))); assert!((a1.x0 - a0.x0 - 10.0).abs() < 1.0, "the left paragraph grows right: {} {}", a0.x0, a1.x0); assert!((b1.x1 - b0.x1 + 10.0).abs() < 1.0, "the right paragraph grows left: {} {}", b0.x1, b1.x1); } diff --git a/crates/text/src/selectors.rs b/crates/text/src/selectors.rs index e3a422460..0306b7e09 100644 --- a/crates/text/src/selectors.rs +++ b/crates/text/src/selectors.rs @@ -71,6 +71,10 @@ impl Mode { pub fn combine(self, acc: f64, v: f64) -> f64 { let r = match self { Mode::Add => acc + v, + // Subtracting more than is selected leaves nothing, not a negative selection (After + // Effects 2026: a Subtract selector over unselected characters leaves their + // Tracking at 0, EXPORTER read-back t8). + Mode::Subtract if acc >= 0.0 => (acc - v).max(0.0), Mode::Subtract => acc - v, Mode::Intersect => acc * v, Mode::Min => acc.min(v), @@ -352,6 +356,9 @@ mod tests { // A lone Subtract inverts. assert_eq!(Mode::Subtract.combine(Mode::Subtract.initial(), 1.0), 0.0); assert_eq!(Mode::Subtract.combine(Mode::Subtract.initial(), 0.0), 1.0); + // Subtracting from what is not selected leaves 0, not a negative selection (AE t8). + assert_eq!(Mode::Subtract.combine(0.0, 1.0), 0.0); + assert_eq!(Mode::Subtract.combine(0.25, 1.0), 0.0); assert_eq!(Mode::from_index(5), Mode::Difference); } diff --git a/docs/fidelity/README.md b/docs/fidelity/README.md index d4c1bf788..22fbd4330 100644 --- a/docs/fidelity/README.md +++ b/docs/fidelity/README.md @@ -90,6 +90,18 @@ Regression test: `rtl_point_text_with_a_justified_paragraph_is_flush_at_its_star AE wraps right-to-left box text slightly wider (its word gaps are 1–2 px narrower than in left-to-right text with the same font), so a 300 px box fits a word more per line. +## Text animator tracking + +Measured on 19 October 2026 with After Effects 2026 (26.2): a text animator's Tracking Amount is in +pixels, not 1/1000 em like the Character panel's tracking (Amount 30 adds 30 px between neighbouring +characters at 80 px and at 40 px, half before and half after each), and a Subtract range selector +over characters the first selector leaves out keeps them at 0 instead of tracking them negatively. +With both, the EXPORTER's t8 layer D (Tracking 30 on characters 2–4 by index, a Subtract selector +over the last 20 %) puts every glyph where AE does (it ended 88 px short). The "Tracking In" text +preset now animates 40 → 0 px (was 400 → 0 thousandths of an em); Lottie export writes a style run's +tracking as pixels. Regression tests: `animator_tracking_is_in_pixels_as_in_after_effects`, +`modes_combine`. + ## Still unmeasured Rendered frame comparisons now have a deterministic `effectcraft_effects::fidelity::compare_frames`