From a3fa000645fdb43b3c01b96a3da1ab865379d58a Mon Sep 17 00:00:00 2001
From: Julian Chang <wyvest@polyfrost.org>
Date: Mon, 5 Oct 2026 07:42:04 -0400
Subject: [PATCH] Port modern GUI scaling

---
 .../mixin/bugfix/gui/GameOptionsMixin.java    | 29 ++++++++++++++++++
 .../sarcio/mixin/bugfix/gui/WindowMixin.java  | 30 +++++++++++++++++++
 src/main/resources/sarcio.mixins.json         |  1 +
 3 files changed, 60 insertions(+)
 create mode 100644 src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/WindowMixin.java

diff --git a/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/GameOptionsMixin.java b/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/GameOptionsMixin.java
index 135f797..7d2ea30 100644
--- a/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/GameOptionsMixin.java
+++ b/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/GameOptionsMixin.java
@@ -3,16 +3,25 @@
 import net.minecraft.client.Minecraft;
 import net.minecraft.client.options.GameOptions;
 import net.minecraft.client.options.KeyBinding;
+import net.minecraft.client.render.Window;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.llamalad7.mixinextras.injector.wrapoperation.Operation;
 import com.llamalad7.mixinextras.injector.wrapoperation.WrapOperation;
+import com.llamalad7.mixinextras.sugar.Local;
+import org.objectweb.asm.Opcodes;
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
 @Mixin(GameOptions.class)
 public class GameOptionsMixin {
+    @Shadow
+    @Final
+    private static String[] GUI_SCALE_SETTINGS;
+
     @Inject(method = "isPressed", at = @At("HEAD"), cancellable = true)
     private static void sarcio$ignoreUnicodeKeys(KeyBinding key, CallbackInfoReturnable<Boolean> cir) {
         if (key.getKeyCode() >= 256) {
@@ -24,4 +33,24 @@ public class GameOptionsMixin {
     private ListenableFuture<?> sarcio$deferResourceRefresh(Minecraft mc, Operation<ListenableFuture<?>> original) {
         return null;
     }
+
+    @WrapOperation(method = "set(Lnet/minecraft/client/options/GameOptions$Option;I)V", at = @At(value = "FIELD", target = "Lnet/minecraft/client/options/GameOptions;guiScale:I", opcode = Opcodes.PUTFIELD))
+    private void sarcio$cycleGuiScale(GameOptions options, int masked, Operation<Void> original, @Local(argsOnly = true) int value) {
+        int current = options.guiScale;
+        int max;
+        try {
+            options.guiScale = 0;
+            max = new Window(Minecraft.getInstance()).getScale();
+        } finally {
+            options.guiScale = current;
+        }
+        original.call(options, Math.floorMod(Math.min(current, max) + value, max + 1));
+    }
+
+    @Inject(method = "translateIntegerValue", at = @At("HEAD"), cancellable = true)
+    private static void sarcio$numericGuiScale(String[] translationKeys, int value, CallbackInfoReturnable<String> cir) {
+        if (translationKeys == GUI_SCALE_SETTINGS && value > 0) {
+            cir.setReturnValue(Integer.toString(value));
+        }
+    }
 }
diff --git a/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/WindowMixin.java b/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/WindowMixin.java
new file mode 100644
index 0000000..56cb20d
--- /dev/null
+++ b/src/main/java/dev/rdh/sarcio/mixin/bugfix/gui/WindowMixin.java
@@ -0,0 +1,30 @@
+package dev.rdh.sarcio.mixin.bugfix.gui;
+
+import com.llamalad7.mixinextras.expression.Definition;
+import com.llamalad7.mixinextras.expression.Expression;
+import com.llamalad7.mixinextras.injector.ModifyExpressionValue;
+import com.llamalad7.mixinextras.injector.wrapoperation.Operation;
+import com.llamalad7.mixinextras.injector.wrapoperation.WrapOperation;
+import net.minecraft.client.render.Window;
+import org.objectweb.asm.Opcodes;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+
+@Mixin(Window.class)
+public class WindowMixin {
+    @Shadow
+    private int scale;
+
+    @WrapOperation(method = "<init>(Lnet/minecraft/client/Minecraft;)V", at = @At(value = "FIELD", target = "Lnet/minecraft/client/render/Window;scale:I", opcode = Opcodes.PUTFIELD))
+    private void sarcio$roundUnicodeScaleUp(Window window, int value, Operation<Void> original) {
+        original.call(window, value == this.scale - 1 ? value + 2 : value);
+    }
+
+    @Definition(id = "scale", field = "Lnet/minecraft/client/render/Window;scale:I")
+    @Expression("this.scale != 1")
+    @ModifyExpressionValue(method = "<init>(Lnet/minecraft/client/Minecraft;)V", at = @At("MIXINEXTRAS:EXPRESSION"))
+    private boolean sarcio$roundScaleOneUp(boolean original) {
+        return true;
+    }
+}
diff --git a/src/main/resources/sarcio.mixins.json b/src/main/resources/sarcio.mixins.json
index 47f044b..308432b 100644
--- a/src/main/resources/sarcio.mixins.json
+++ b/src/main/resources/sarcio.mixins.json
@@ -75,6 +75,7 @@
     "bugfix.render.ItemModelShaperMixin",
     "bugfix.ResourcePacksMixin",
     "bugfix.gui.GameOptionsMixin",
+    "bugfix.gui.WindowMixin",
     "bugfix.gui.SoundSliderWidgetMixin",
     "bugfix.gui.InventoryMenuMixin",
     "bugfix.gui.DeathScreenMixin",