Merge pull request #1158 from nanox333/fix/551-shift-space-every-frame

# Conflicts:
#	docs/ui-parity.md

crates/engine/src/preview.rs

@@ -205,9 +205,8 @@ impl PreviewPreset {
     pub fn default_for(s: PreviewShortcut) -> Self {
         let d = PreviewPreset::default();
         match s {
-            PreviewShortcut::Spacebar => d,
-            // A lighter preview: every other frame.
-            PreviewShortcut::ShiftSpacebar => PreviewPreset { skip: 1, ..d },
+            // Frame skipping is off by default; set Skip to play fewer frames.
+            PreviewShortcut::Spacebar | PreviewShortcut::ShiftSpacebar => d,
             PreviewShortcut::Numpad0 => PreviewPreset { range: PreviewRange::WorkArea, play_from: PlayFrom::RangeStart, ..d },
             PreviewShortcut::ShiftNumpad0 => {
                 PreviewPreset { range: PreviewRange::WorkArea, play_from: PlayFrom::RangeStart, skip: 1, resolution: PreviewResolution::Half, ..d }
@@ -509,6 +508,13 @@ mod tests {
         assert_eq!(pl.frame_after(237, 1), None);
     }
 
+    /// #551: Shift+Spacebar used to skip every other frame out of the box.
+    #[test]
+    fn shift_spacebar_plays_every_frame_by_default() {
+        assert_eq!(PreviewPreset::default_for(PreviewShortcut::ShiftSpacebar).skip, 0);
+        assert_eq!(PreviewPreset::default_for(PreviewShortcut::ShiftSpacebar), PreviewPreset::default_for(PreviewShortcut::Spacebar));
+    }
+
     #[test]
     fn settings_commands_round_trip() {
         let mut s = comp_session();

crates/ui-egui/tests/ui_preview_align.rs

@@ -118,7 +118,8 @@ fn playback_follows_the_shortcut_options() {
     h.step();
     assert!(h.state().playback.playing);
     assert_eq!(h.state().playback.shortcut, PreviewShortcut::ShiftSpacebar);
-    assert_eq!(h.state().playback.plan.unwrap().step, 2);
+    // Every frame by default (#551): Skip is 0 until the user sets it.
+    assert_eq!(h.state().playback.plan.unwrap().step, 1);
 }
 
 #[test]

docs/ui-parity.md

@@ -27,7 +27,7 @@ feel and platform differences, and the 26.x interface changes are not in yet.
 | Keyboard shortcuts | After Effects' defaults; Keyboard Shortcuts editor that rebinds and saves sets | 75% | Shortcut editor in Settings; #467 (adding shortcuts on Linux), #428 and #336 are closed; no shortcuts for scripts |
 | Drag and drop | Project → Timeline / viewer / New Comp / Render Queue; effects onto layers; files from the OS | 65% | `ui_drag_drop`; OS drops fail on Wayland (winit) and some Linux setups (#268); #552, #351 (multi-file drops) and #511 (crash dragging over the import dialog) are closed |
 | Text editing on canvas | Point and paragraph text, per-character styles, Character / Paragraph panels, OpenType and variable axes | 70% | `ui_text_edit`, `ui_font_search`; paragraph alignment inverted (#316); toolbar font options (#550); font search by typing (#583) is closed; the font menus' variable-font filter (26.3) landed (#741) |
-| Preview feel | Spacebar / Numpad 0 previews, RAM preview, cache bars, adaptive resolution | 55% | `ui_ram_preview`, `ui_live_preview`; stutter (#595, #304), Shift+Space default (#551); scrubbing lag (#329, closed by #784) |
+| Preview feel | Spacebar / Numpad 0 previews, RAM preview, cache bars, adaptive resolution | 55% | `ui_ram_preview`, `ui_live_preview`; stutter (#595, #304),; scrubbing lag (#329, closed by #784) |
 | Home screen, Learn, templates | Home with recent projects, template gallery, interactive Learn tutorials | 70% | Layout nitpicks (#581); Home literals untranslated (#574) |
 | Quick Apply (26.2) | Search to apply effects, presets or commands | partial | A command palette exists; not After Effects' Quick Apply |
 | Accessibility | AccessKit enabled; focus labels tested; Project panel keyboard navigation and accessible names (#776) | 20% | No screen-reader pass or keyboard-navigation audit of the other panels; no contrast check |