Every <OnLoad> in the interface read text widths as 0

`seat_text_measurer`'s own doc says what it is for: *"so `GetStringWidth` right after `SetText` measures, as the reference answers it inline (`0x79e510` → `0x772890`). Also seated before the manifest loads, for every `<OnLoad>`."* It was not seated. `UiFontAtlas` is inserted by an `Update` system through `Commands`, so it appears at the next command flush — and the interface load runs on the `InWorld` state transition, which comes first. `seat_raster_seam_for_load` then took its `else { return }` and the VM went through the whole load with **no text measurer at all**, which `ensure_measured` answers by returning at its first line. So for the entire UI load — all of FrameXML and every addon — `FontString:GetWidth()`, `GetHeight()` and `GetStringWidth()` answered **0** for a string that plainly had text. Measured on grom's install: dozens of them, including every unit-popup entry, every `StaticPopup` button and the four radio labels this was found through. What it costs is any `<OnLoad>` that lays something out from a label's width, which is an ordinary thing for an addon to do. `AdvancedTradeSkillWindow2.lua:1642` puts its Name radio button at `ATSWDifficultySortCheckboxText2:GetWidth() + 5` to the right of the Difficulty one: the stored offset came out **5.0** where it should be 53.8, so "Difficulty" was drawn across "Category" 37 px to its left. grom, 2026-11-05: *"its loading now, but barely functioning."* Re-running `ATSW_OnLoad()` by hand from a live session gave 53.8 — the same code, the same frame, a measurer away. `ensure_font_atlas(&mut World)` is `init`'s body for a caller that holds the world, called from `seat_raster_seam_for_load`; `init` keeps its own path for every later frame. A world that still cannot build one (no chain, no window) now warns instead of loading the interface in silence. Verified: the ATSW2 offset is 53.8 at load, and a walk of the whole loaded interface finds **0** FontStrings that have text and measure 0 (dozens before). benilla-app 4243 pass / 12 fail, the recorded baseline with an identical name set. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01SgstFWtn1RxEJ5kVrpgYwn
2026-11-05 11:48:29 -07:00
parent 6306fed1ca
commit 8c6fb4e425
4 changed files with 56 additions and 2 deletions
@@ -738,6 +738,16 @@ fn seat_raster_seam_for_load(world: &mut World, script: &mut UiScript) {
        // out yet.
        script.set_screen_size(w / s, h / s);
    }
+    // Built here if it is not built yet: the atlas's own `init` is an `Update` system inserting
+    // through `Commands`, and this runs on the `InWorld` transition, which comes first — see
+    // `ui_text::engine::gpu::ensure_font_atlas` for what a missing measurer costs the load.
+    if !crate::ui_text::ensure_font_atlas(world) {
+        warn!(
+            "ui_script: no font atlas at world entry — every GetStringWidth during this UI load \
+             will answer 0, and any `<OnLoad>` laying out from a label's width will be wrong"
+        );
+        return;
+    }
    let Some(atlas) = world.get_resource::<crate::ui_text::UiFontAtlas>() else {
        return;
    };
@@ -77,6 +77,50 @@ fn init(
    });
 }

+/// [`init`] for a caller that holds the world, which is how the UI load reaches it.
+///
+/// [`init`] is an `Update` system that inserts through `Commands`, so the resource appears at the
+/// next command flush — and the interface load runs on the `InWorld` state transition, which can
+/// and does come first. The cost of missing it is not cosmetic: with no atlas there is no text
+/// measurer, so for the whole of the UI load **every `GetStringWidth` and every FontString's
+/// `GetWidth` answers 0**, where the reference measures inline and always knows (`0x79e510` →
+/// `0x772890`). Every `<OnLoad>` in FrameXML and in every addon that lays something out from a
+/// label's width reads a zero — `AdvancedTradeSkillWindow2.lua:1642` puts its Name radio button
+/// `ATSWDifficultySortCheckboxText2:GetWidth() + 5` to the right of the Difficulty one and so
+/// stacked the two labels on top of each other, 5 px apart instead of 53.8.
+///
+/// Returns whether an atlas is in the world afterwards.
+pub(crate) fn ensure_font_atlas(world: &mut World) -> bool {
+    if world.contains_resource::<UiFontAtlas>() {
+        return true;
+    }
+    let scale_factor = {
+        let mut q = world.query_filtered::<&Window, With<PrimaryWindow>>();
+        match q.single(world) {
+            Ok(window) => window.scale_factor(),
+            Err(_) => return false,
+        }
+    };
+    let engine = {
+        let Some(world_assets) = world.get_resource::<WorldAssets>() else {
+            return false;
+        };
+        let Some(images) = world.get_resource::<Assets<Image>>() else {
+            return false;
+        };
+        match TextEngine::load(world_assets, images, scale_factor) {
+            Some(engine) => engine,
+            None => return false,
+        }
+    };
+    world.insert_resource(UiFontAtlas {
+        engine: Arc::new(Mutex::new(engine)),
+        generation: 0,
+        ellipsis: crate::ui_text::EllipsisMemo::default(),
+    });
+    true
+}
+
 /// The frame boundary: follow the window's DPI, carry out a pending reset, create the sheet's
 /// texture once, and hand this frame's cells to the render world. A reset waits for this boundary
 /// so no UV moves while quads that use it are still being pushed.
@@ -37,7 +37,7 @@ use cosmic_text::{
 use benilla_assets::{LockRecover, WorldAssets};

 use faces::{hhea_ascent_ratio, register_font, CLIENT_FONTS};
-pub(crate) use gpu::UiTextPlugin;
+pub(crate) use gpu::{ensure_font_atlas, UiTextPlugin};

 use super::outline::outlined_cell;
 use super::pack::{Cell, Sheet};
@@ -20,7 +20,7 @@ mod measurer;
 mod outline;
 mod pack;

-pub(crate) use engine::{UiFontAtlas, UiTextPlugin};
+pub(crate) use engine::{ensure_font_atlas, UiFontAtlas, UiTextPlugin};

 use benilla_ui::script::Outline;
 use benilla_ui::widget::RegionHandle;