f60856b1

Add dirty-row packing helpers

a73x 2026-04-08 18:32

Commit message

Add dirty-row packing helpers

src/main.zig

+    try std.testing.expectEqual(@as(usize, 0), plan.rows_to_rebuild.count());
+test "repackRowCaches assigns contiguous offsets" {
+    var rows = [_]RowInstanceCache{
+        .{
+            .instances = try makeTestInstances(std.testing.allocator, 2),
+            .gpu_offset_instances = 99,
+            .gpu_len_instances = 0,
+        },
+        .{
+            .instances = try makeTestInstances(std.testing.allocator, 3),
+            .gpu_offset_instances = 99,
+            .gpu_len_instances = 0,
+        },
+    };
+    defer for (&rows) |*row| row.instances.deinit(std.testing.allocator);
+    var packed_instances: std.ArrayListUnmanaged(renderer.Instance) = .empty;
+    defer packed_instances.deinit(std.testing.allocator);
+    const total = try repackRowCaches(std.testing.allocator, &packed_instances, &rows, &.{});
+    try std.testing.expectEqual(@as(u32, 0), rows[0].gpu_offset_instances);
+    try std.testing.expectEqual(@as(u32, 2), rows[1].gpu_offset_instances);
+    try std.testing.expectEqual(@as(u32, 5), total);
+}
+test "markLayoutDirtyOnLenChange returns true when row length changes" {
+    try std.testing.expect(markLayoutDirtyOnLenChange(2, 3));
+    try std.testing.expect(!markLayoutDirtyOnLenChange(3, 3));
+}
+const RowInstanceCache = struct {
+    instances: std.ArrayListUnmanaged(renderer.Instance) = .empty,
+    gpu_offset_instances: u32 = 0,
+    gpu_len_instances: u32 = 0,
+    fn deinit(self: *RowInstanceCache, alloc: std.mem.Allocator) void {
+        self.instances.deinit(alloc);
+    }
+};
+fn repackRowCaches(
+    alloc: std.mem.Allocator,
+    packed_instances: *std.ArrayListUnmanaged(renderer.Instance),
+    rows: []RowInstanceCache,
+    cursor_instances: []const renderer.Instance,
+) !u32 {
+    packed_instances.clearRetainingCapacity();
+    var offset: u32 = 0;
+    for (rows) |*row| {
+        row.gpu_offset_instances = offset;
+        row.gpu_len_instances = @intCast(row.instances.items.len);
+        try packed_instances.appendSlice(alloc, row.instances.items);
+        offset += @intCast(row.instances.items.len);
+    }
+    try packed_instances.appendSlice(alloc, cursor_instances);
+    return offset + @as(u32, @intCast(cursor_instances.len));
+}
+fn markLayoutDirtyOnLenChange(old_len: usize, new_len: usize) bool {
+    return old_len != new_len;
+}
+fn makeTestInstances(
+    alloc: std.mem.Allocator,
+    count: usize,
+) !std.ArrayListUnmanaged(renderer.Instance) {
+    var instances: std.ArrayListUnmanaged(renderer.Instance) = .empty;
+    try instances.ensureTotalCapacity(alloc, count);
+    var i: usize = 0;
+    while (i < count) : (i += 1) {
+        try instances.append(alloc, .{
+            .cell_pos = .{ @floatFromInt(i), 0.0 },
+            .glyph_size = .{ 1.0, 1.0 },
+            .glyph_bearing = .{ 0.0, 0.0 },
+            .uv_rect = .{ 0.0, 0.0, 1.0, 1.0 },
+            .fg = .{ 1.0, 1.0, 1.0, 1.0 },
+            .bg = .{ 0.0, 0.0, 0.0, 1.0 },
+        });
+    }
+    return instances;
+}
+fn runDrawSmokeTest(alloc: std.mem.Allocator) !void {
+    var conn = try wayland_client.Connection.init();
+    defer conn.deinit();