Let a pane's tag take a row for each line it holds

A tag that is a text can hold a newline, and the tagline, the body under it
and the pointer all assumed one row. The pane's tag now takes a row per line
(up to eight, and never the body's last row); the body starts below it, the
rows a pointer counts start the body after the tag's lines, a click on any
line puts the tag's cursor there, and a pixel shell gets a tag layer per
line. A tag of one line draws exactly as before.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/tag_layer.zig b/src/tag_layer.zig
index 52da297d..ac7c4ac2 100644
--- a/src/tag_layer.zig
+++ b/src/tag_layer.zig
@@ -13,6 +13,8 @@ pub const Hit = struct {
     id: u16,
     serial: u32,
     col: u16,
+    /// Which line of a taller tag the layer draws.
+    line: u16 = 0,
     pixel_x: f32,
     pixel_y: f32,
     metrics: pardes.RowMetrics,
@@ -21,6 +23,9 @@ pub const Layer = struct {
     kind: Kind = .workspace,
     id: u16 = 0,
     serial: u32 = 0,
+    /// A pane's tag taller than a line is drawn a layer to a line; this is
+    /// which one, counted from its first.
+    line: u16 = 0,
     viewport: pardes.Rect = .{ .x = 0, .y = 0, .w = 0, .h = 0 },
     cols: u16 = 0,
     bg: [3]u8 = .{ 0, 0, 0 },
@@ -54,6 +59,7 @@ pub const Layer = struct {
             .kind = layer.kind,
             .id = layer.id,
             .serial = layer.serial,
+            .line = layer.line,
             .col = @intFromFloat(@min(@as(f32, @floatFromInt(layer.cols - 1)), @floor(dx / tw))),
             .pixel_x = x,
             .pixel_y = y,