src/main/java/org/saturnclient/impl/ui/GlassRenderer.java

@@ -17,7 +17,11 @@ package org.saturnclient.impl.ui;
 //? if >=1.21.6 {
 import java.io.Reader;
 import java.util.HashMap;
+//? if >=26.1
+//import java.util.LinkedHashSet;
 import java.util.Map;
+//? if >=26.1
+//import java.util.Set;
 
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
@@ -85,13 +89,24 @@ public final class GlassRenderer {
     private GlassRenderer() {
     }
 
+    // From 26.1 the GUI is built before the frame's world is drawn, so the main framebuffer still
+    // holds the last frame, glass included. The copies wait until the GUI renderer is about to draw
+    // (GuiRendererMixin), when it holds this frame's world and panorama.
+    //? if >=26.1 {
+    /*private static final Set<Integer> PENDING = new LinkedHashSet<>();
+    *///?}
+
+    private static RenderTarget mainTarget() {
+        //? if >=26.2 {
+        /*return SaturnClient.client.gameRenderer.mainRenderTarget();
+        *///?} else
+        return SaturnClient.client.getMainRenderTarget();
+    }
+
     // Copies the main framebuffer and blurs the copy by blur. Call once a frame for each blur, while
     // the screen builds its GUI, before drawing glass with it.
     public static void captureBackdrop(int blur) {
-        //? if >=26.2 {
-        /*RenderTarget main = SaturnClient.client.gameRenderer.mainRenderTarget();
-        *///?} else
-        RenderTarget main = SaturnClient.client.getMainRenderTarget();
+        RenderTarget main = mainTarget();
         int width = main.width;
         int height = main.height;
 
@@ -108,6 +123,29 @@ public final class GlassRenderer {
         //? if <1.21.11
         //backdrop.getColorTexture().setTextureFilter(FilterMode.LINEAR, false);
 
+        //? if >=26.1 {
+        /*PENDING.add(blur);
+    }
+
+    // Copies and blurs the backdrops the GUI asked for this frame. GuiRendererMixin calls it once the
+    // world and the panorama are drawn, before the GUI.
+    public static void blurPendingBackdrops() {
+        RenderTarget main = mainTarget();
+        for (int blur : PENDING) {
+            TextureTarget backdrop = BACKDROPS.get(blur);
+            // The GUI already refers to the backdrop's texture, so after a resize it keeps the last
+            // frame's until the next one.
+            if (backdrop != null && backdrop.width == main.width && backdrop.height == main.height) {
+                blurBackdrop(main, backdrop, blur);
+            }
+        }
+        PENDING.clear();
+    }
+
+    private static void blurBackdrop(RenderTarget main, TextureTarget backdrop, int blur) {
+        int width = main.width;
+        int height = main.height;
+        *///?}
         RenderSystem.getDevice().createCommandEncoder().copyTextureToTexture(
                 main.getColorTexture(), backdrop.getColorTexture(), 0, 0, 0, 0, 0, width, height);
 
@@ -132,6 +170,9 @@ public final class GlassRenderer {
     private static void release(int kept) {
         BACKDROPS.entrySet().removeIf(entry -> {
             boolean unused = entry.getKey() != kept && !isSet(entry.getKey());
+            // The GUI already refers to this frame's pending backdrops.
+            //? if >=26.1
+            //unused &= !PENDING.contains(entry.getKey());
             if (unused) {
                 entry.getValue().destroyBuffers();
             }
@@ -139,6 +180,9 @@ public final class GlassRenderer {
         });
         BLURS.entrySet().removeIf(entry -> {
             boolean unused = entry.getKey() != kept && !isSet(entry.getKey());
+            // The GUI already refers to this frame's pending backdrops.
+            //? if >=26.1
+            //unused &= !PENDING.contains(entry.getKey());
             if (unused && entry.getValue() != null) {
                 entry.getValue().close();
             }

src/main/java/org/saturnclient/saturnclient/mixin/GuiRendererMixin.java

@@ -5,16 +5,20 @@ package org.saturnclient.saturnclient.mixin;
 import com.llamalad7.mixinextras.injector.wrapoperation.WrapOperation;
 import net.minecraft.client.gui.render.GuiRenderer;
 import net.minecraft.client.renderer.CubeMap;
+import org.saturnclient.impl.ui.GlassRenderer;
 import org.saturnclient.impl.ui.SaturnScreenFabric;
 import org.saturnclient.impl.ui.Screens;
 import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 *///?} else
 import net.minecraft.client.Minecraft;
 import org.spongepowered.asm.mixin.Mixin;
 
 /**
  * From 26.1 GuiRenderer draws the menu panorama from its own cube map, which is vanilla's. While a
- * Saturn screen is open, this draws Saturn's panorama instead. Before 26.1 SaturnScreenFabric draws
+ * Saturn screen is open, this draws Saturn's panorama instead. It also blurs the glass backdrops
+ * once the panorama is drawn. Before 26.1 SaturnScreenFabric draws
  * the panorama itself, so this mixin is empty there, and it targets Minecraft because GuiRenderer
  * doesn't exist before 1.21.6. It stays registered, keeping saturnclient.mixins.json the same for
  * every version.
@@ -27,6 +31,13 @@ public class GuiRendererMixin {
         boolean saturnScreen = Screens.current() instanceof SaturnScreenFabric;
         original.call(saturnScreen ? SaturnScreenFabric.PANORAMA_RENDERER : cubeMap, xRot, yRot);
     }
+
+    // The glass backdrops are copied here, with the frame's world and panorama drawn and the GUI not
+    // yet: the GUI is built before the frame is drawn (see GlassRenderer).
+    @Inject(method = "render", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/gui/render/GuiRenderer;prepare()V"))
+    private void saturn$blurGlassBackdrops(CallbackInfo ci) {
+        GlassRenderer.blurPendingBackdrops();
+    }
 }
 *///?} else {
 @Mixin(Minecraft.class)