Move the frame into draw.zig and the transitions out of layout.zig

Pure moves, no behaviour change. draw.zig holds the whole core frame in
order: render, the pane, tag, header and notice painters it calls, and the
character-effect composition (Pardes.render stays a declaration alias).
Presentation.zig is the panel presentation state as a file struct, and
animation.zig the easing curves, transition kinds, tracks and boxes, the
character effects' sources and the generic displayed-value transition, all
of which lived in layout.zig. layout.zig keeps only layout.

2 files changed, 16 insertions, 15 deletions

diff --git a/src/tty/panel_compositor.zig b/src/tty/panel_compositor.zig
index 9363841a..67d3a6e6 100644
--- a/src/tty/panel_compositor.zig
+++ b/src/tty/panel_compositor.zig
@@ -8,9 +8,10 @@
 const std = @import("std");
 const pardes = @import("../pardes.zig");
 const layout = @import("../layout.zig");
+const animation = @import("../animation.zig");
 
-const Box = layout.Box;
-const Track = layout.Track;
+const Box = animation.Box;
+const Track = animation.Track;
 
 /// Kitty placements cannot be resampled through the character-grid transform.
 /// Keep their transmitted pixels cached, but omit the placement while its pane
@@ -77,7 +78,7 @@ pub fn compose(
     // Stable layout motion first, newly opening panels above it, and closing
     // tombstones last. A closing pane no longer owns input or canonical cells,
     // but its frozen old content remains the top visual until it slides out.
-    for ([_]layout.Phase{ .moving, .opening, .closing }) |phase| {
+    for ([_]animation.Phase{ .moving, .opening, .closing }) |phase| {
         for (tracks) |track| {
             if (!drawable(source, track) or track.phase != phase) continue;
             switch (track.effect) {
@@ -139,7 +140,7 @@ fn dissolve(out: *pardes.Surface, source: *const pardes.Surface, track: Track) v
         var x = area.x0;
         while (x < area.x1) : (x += 1) {
             if (!source.panelCellChanged(x, y)) continue;
-            if (layout.dissolveRevealed(
+            if (animation.dissolveRevealed(
                 track.serial,
                 x - area.x0,
                 y - area.y0,
@@ -339,7 +340,7 @@ test "TTY content effects never touch cells outside the published diff" {
     var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
     defer arena.deinit();
 
-    for ([_]layout.Transition{ .ascii, .dissolve }) |effect| {
+    for ([_]animation.Transition{ .ascii, .dissolve }) |effect| {
         const track: Track = .{
             .serial = 17,
             .effect = effect,
@@ -366,7 +367,7 @@ test "content transition without a diff snaps to canonical surface" {
     var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
     defer arena.deinit();
 
-    for ([_]layout.Transition{ .dissolve, .ascii, .vertical }) |effect| {
+    for ([_]animation.Transition{ .dissolve, .ascii, .vertical }) |effect| {
         const track: Track = .{
             .effect = effect,
             .phase = .opening,
@@ -391,7 +392,7 @@ test "exact transition endpoint preserves the canonical cursor" {
     };
     const track: Track = .{
         .effect = .ascii,
-        .frame = layout.Transition.ascii.frames() - 1,
+        .frame = animation.Transition.ascii.frames() - 1,
         .from = .{ .w = 1, .h = 1 },
         .to = .{ .w = 1, .h = 1 },
     };
@@ -431,7 +432,7 @@ test "vertical opening rises through a fixed old-grid clip" {
         .serial = 5,
         .phase = .opening,
         .effect = .vertical,
-        .from = layout.openingBox(.vertical, target, 3),
+        .from = animation.openingBox(.vertical, target, 3),
         .to = target,
     };
 
@@ -485,7 +486,7 @@ test "vertical closing drops frozen content over canonical cells" {
         .phase = .closing,
         .effect = .vertical,
         .from = old_box,
-        .to = layout.closingBox(.vertical, old_box),
+        .to = animation.closingBox(.vertical, old_box),
     };
 
     const first = try compose(arena.allocator(), &surface, &.{track}, null);
@@ -530,13 +531,13 @@ test "closing content paints after opening content regardless of track order" {
         .phase = .closing,
         .effect = .vertical,
         .from = box,
-        .to = layout.closingBox(.vertical, box),
+        .to = animation.closingBox(.vertical, box),
     };
     const opening: Track = .{
         .serial = 2,
         .phase = .opening,
         .effect = .ascii,
-        .frame = layout.Transition.ascii.frames() - 1,
+        .frame = animation.Transition.ascii.frames() - 1,
         .from = box,
         .to = box,
     };
@@ -691,8 +692,8 @@ test "active panel transition hides only its own native attachment" {
     const tracks = [_]Track{
         .{ .serial = 41, .effect = .slide, .frame = 0 },
         .{ .serial = 42, .effect = .ascii, .frame = 0 },
-        .{ .serial = 43, .effect = .zoom, .frame = layout.Transition.zoom.frames() - 1 },
-        .{ .serial = 44, .effect = .zoom, .frame = layout.Transition.zoom.frames() },
+        .{ .serial = 43, .effect = .zoom, .frame = animation.Transition.zoom.frames() - 1 },
+        .{ .serial = 44, .effect = .zoom, .frame = animation.Transition.zoom.frames() },
         .{ .serial = 45, .phase = .opening, .effect = .vertical, .frame = 0 },
     };
 
diff --git a/src/tty/tty.zig b/src/tty/tty.zig
index 32f9138f..66e551b1 100644
--- a/src/tty/tty.zig
+++ b/src/tty/tty.zig
@@ -899,7 +899,7 @@ const Shell = struct {
     caps_pending: bool = true,
     check_files: bool = false,
     in_paste: bool = false,
-    tracks: []const pardes.layout.Track = &.{},
+    tracks: []const pardes.animation.Track = &.{},
 
     fn of(ctx: ?*anyopaque) *Shell {
         return @ptrCast(@alignCast(ctx.?));
@@ -1532,7 +1532,7 @@ fn tickWatch(io: std.Io, loop: *Loop) void {
     while (true) {
         tick_request.waitUncancelable(io);
         tick_request.reset();
-        var ts: libc.timespec = .{ .sec = 0, .nsec = @as(isize, pardes.layout.Animation.frame_ms) * std.time.ns_per_ms };
+        var ts: libc.timespec = .{ .sec = 0, .nsec = @as(isize, pardes.animation.Animation.frame_ms) * std.time.ns_per_ms };
         _ = libc.nanosleep(&ts, null);
         loop.postEvent(.tick) catch {};
     }