Fix Render GUI on Retina Screens (fixes #338)

window.getFramebufferWidth/Height() should be used instead of window.getWidth/Height()

Co-authored-by: Jonas Herzig <me@johni0702.de>

versions/1.12.2/src/main/java/com/replaymod/core/versions/Window.java

@@ -34,6 +34,11 @@ public class Window implements MainWindowAccessor {
         mc.displayHeight = value;
     }
 
+    @Override
+    public void invokeUpdateFramebufferSize() {
+        // no-op, pre-LWJGL3 MC doesn't differentiate between window and framebuffer size
+    }
+
     public long getHandle() {
         return 0;
     }

versions/1.12.2/src/main/java/com/replaymod/render/mixin/MainWindowAccessor.java

@@ -3,6 +3,7 @@ package com.replaymod.render.mixin;
 import net.minecraft.client.Minecraft;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.gen.Accessor;
+import org.spongepowered.asm.mixin.gen.Invoker;
 
 @Mixin(Minecraft.class)
 public interface MainWindowAccessor {
@@ -14,4 +15,6 @@ public interface MainWindowAccessor {
     int getFramebufferHeight();
     @Accessor("displayHeight")
     void setFramebufferHeight(int value);
+    @Invoker
+    void invokeUpdateFramebufferSize();
 }