From 94c41840680afd414acb1195889bb88588901100 Mon Sep 17 00:00:00 2001
From: Carter Anderson <mcanders1@gmail.com>
Date: Sat, 27 Mar 2021 03:03:47 +0000
Subject: [PATCH] Text responds to scale factor changes (#1769)

Fixes #1768

If the scale factor changes, queue up all text to be drawn instead of just changed text.
---
 crates/bevy_ui/src/widget/text.rs | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/crates/bevy_ui/src/widget/text.rs b/crates/bevy_ui/src/widget/text.rs
index f9e7dc8bc429d..a8dce7ea1a191 100644
--- a/crates/bevy_ui/src/widget/text.rs
+++ b/crates/bevy_ui/src/widget/text.rs
@@ -2,7 +2,7 @@ use crate::{CalculatedSize, Node, Style, Val};
 use bevy_asset::Assets;
 use bevy_ecs::{
     entity::Entity,
-    query::{Changed, Or, Without},
+    query::{Changed, Or, With, Without},
     system::{Local, Query, QuerySet, Res, ResMut},
 };
 use bevy_math::Size;
@@ -45,6 +45,7 @@ pub fn text_constraint(min_size: Val, size: Val, max_size: Val, scale_factor: f6
 #[allow(clippy::too_many_arguments)]
 pub fn text_system(
     mut queued_text: Local<QueuedText>,
+    mut last_scale_factor: Local<f64>,
     mut textures: ResMut<Assets<Texture>>,
     fonts: Res<Assets<Font>>,
     windows: Res<Windows>,
@@ -53,6 +54,7 @@ pub fn text_system(
     mut text_pipeline: ResMut<DefaultTextPipeline>,
     mut text_queries: QuerySet<(
         Query<Entity, Or<(Changed<Text>, Changed<Style>)>>,
+        Query<Entity, (With<Text>, With<Style>)>,
         Query<(&Text, &Style, &mut CalculatedSize)>,
     )>,
 ) {
@@ -64,9 +66,18 @@ pub fn text_system(
 
     let inv_scale_factor = 1. / scale_factor;
 
-    // Adds all entities where the text or the style has changed to the local queue
-    for entity in text_queries.q0_mut().iter_mut() {
-        queued_text.entities.push(entity);
+    #[allow(clippy::float_cmp)]
+    if *last_scale_factor == scale_factor {
+        // Adds all entities where the text or the style has changed to the local queue
+        for entity in text_queries.q0().iter() {
+            queued_text.entities.push(entity);
+        }
+    } else {
+        // If the scale factor has changed, queue all text
+        for entity in text_queries.q1().iter() {
+            queued_text.entities.push(entity);
+        }
+        *last_scale_factor = scale_factor;
     }
 
     if queued_text.entities.is_empty() {
@@ -75,7 +86,7 @@ pub fn text_system(
 
     // Computes all text in the local queue
     let mut new_queue = Vec::new();
-    let query = text_queries.q1_mut();
+    let query = text_queries.q2_mut();
     for entity in queued_text.entities.drain(..) {
         if let Ok((text, style, mut calculated_size)) = query.get_mut(entity) {
             let node_size = Size::new(