9d6c13c8

Add cursor cache rebuild logic

a73x 2026-04-08 19:20

Commit message

Add cursor cache rebuild logic

src/main.zig

+    try std.testing.expectEqualDeep([2]f32{ 9.0, 10.0 }, packed_instances.items[2].cell_pos);
+test "rebuildCursorInstances emits visible cursor instance without changing layout state when count is unchanged" {
+    var cache = RenderCache.empty;
+    defer cache.deinit(std.testing.allocator);
+    cache.cursor_instances = try makeTestInstances(std.testing.allocator, 1);
+    cache.cursor_instances.items[0].cell_pos = .{ 99.0, 99.0 };
+    cache.layout_dirty = false;
+    var cursor_instances = try makeTestInstances(std.testing.allocator, 1);
+    defer cursor_instances.deinit(std.testing.allocator);
+    cursor_instances.items[0].cell_pos = .{ 4.0, 7.0 };
+    const rebuilt = try cache.rebuildCursorInstances(std.testing.allocator, cursor_instances.items);
+    try std.testing.expect(!rebuilt.len_changed);
+    try std.testing.expectEqual(@as(usize, 1), cache.cursor_instances.items.len);
+    try std.testing.expectEqualDeep([2]f32{ 4.0, 7.0 }, cache.cursor_instances.items[0].cell_pos);
+    try std.testing.expect(!cache.layout_dirty);
+}
+test "rebuildCursorInstances marks layout dirty when cursor instance count changes" {
+    var cache = RenderCache.empty;
+    defer cache.deinit(std.testing.allocator);
+    cache.cursor_instances = try makeTestInstances(std.testing.allocator, 1);
+    cache.layout_dirty = false;
+    const rebuilt = try cache.rebuildCursorInstances(std.testing.allocator, &.{});
+    try std.testing.expect(rebuilt.len_changed);
+    try std.testing.expectEqual(@as(usize, 0), cache.cursor_instances.items.len);
+    try std.testing.expect(cache.layout_dirty);
+}
+test "rebuildRowInstances emits expected instances for a colored glyph row" {
+    var term = try vt.Terminal.init(std.testing.allocator, .{
+        .cols = 80,
@@ @@ -1012,6 +1046,23 @@ const RenderCache = struct { @@
+        self.total_instance_count = 0;
+        self.layout_dirty = true;
+    fn rebuildCursorInstances(
+        self: *RenderCache,
+        alloc: std.mem.Allocator,
+        cursor_instances: []const renderer.Instance,
+    ) !RowRebuildResult {
+        const old_len = self.cursor_instances.items.len;
+        self.cursor_instances.clearRetainingCapacity();
+        try self.cursor_instances.appendSlice(alloc, cursor_instances);
+        const len_changed = markLayoutDirtyOnLenChange(old_len, self.cursor_instances.items.len);
+        if (len_changed) self.layout_dirty = true;
+        return .{
+            .len_changed = len_changed,
+        };
+    }
+};
+const RowPackResult = struct {