NeoForge/patches/net/minecraft/client/gui/render/GuiRenderer.java.patch

--- a/net/minecraft/client/gui/render/GuiRenderer.java
+++ b/net/minecraft/client/gui/render/GuiRenderer.java
@@ -88,7 +_,8 @@
     private final Projection guiProjection = new Projection();
     private final ProjectionMatrixBuffer guiProjectionMatrixBuffer = new ProjectionMatrixBuffer("gui");
     private final FeatureRenderDispatcher featureRenderDispatcher;
-    private final Map<Class<? extends PictureInPictureRenderState>, PictureInPictureRenderer<?>> pictureInPictureRenderers;
+    private final Map<Class<? extends PictureInPictureRenderState>, net.neoforged.neoforge.client.gui.PictureInPictureRendererPool<?>> pictureInPictureRendererPools;
+    private final Set<PictureInPictureRenderState> pictureInPictureRenderStatesScratch = new it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet<>();
     private @Nullable GuiItemAtlas itemAtlas;
     private int cachedGuiScale;
     private final CubeMap cubeMap = new CubeMap(Identifier.withDefaultNamespace("textures/gui/title/background/panorama"));
@@ -97,16 +_,10 @@
     private @Nullable TextureSetup previousTextureSetup = null;
     private StagedVertexBuffer.@Nullable Draw previousDraw;
 
-    public GuiRenderer(GuiRenderState renderState, FeatureRenderDispatcher featureRenderDispatcher, List<PictureInPictureRenderer<?>> pictureInPictureRenderers) {
+    public GuiRenderer(GuiRenderState renderState, FeatureRenderDispatcher featureRenderDispatcher, List<net.neoforged.neoforge.client.gui.PictureInPictureRendererRegistration<?>> pipRendererFactories) {
         this.renderState = renderState;
         this.featureRenderDispatcher = featureRenderDispatcher;
-        Builder<Class<? extends PictureInPictureRenderState>, PictureInPictureRenderer<?>> builder = ImmutableMap.builder();
-
-        for (PictureInPictureRenderer<?> pictureInPictureRenderer : pictureInPictureRenderers) {
-            builder.put((Class<? extends PictureInPictureRenderState>)pictureInPictureRenderer.getRenderStateClass(), pictureInPictureRenderer);
-        }
-
-        this.pictureInPictureRenderers = builder.buildOrThrow();
+        this.pictureInPictureRendererPools = net.neoforged.neoforge.client.gui.PictureInPictureRendererPool.createPools(pipRendererFactories);
     }
 
     public void endFrame() {
@@ -135,6 +_,7 @@
         this.renderState.reset();
         this.firstDrawIndexAfterBlur = Integer.MAX_VALUE;
         this.clearUnusedOversizedItemRenderers();
+        this.pictureInPictureRendererPools.values().forEach(net.neoforged.neoforge.client.gui.PictureInPictureRendererPool::clearUnusedRenderers);
         if (SharedConstants.DEBUG_SHUFFLE_UI_RENDERING_ORDER) {
             RenderPipeline.updateSortKeySeed();
             TextureSetup.updateSortKeySeed();
@@ -229,6 +_,7 @@
         ScreenRectangle scissorArea = elementState.scissorArea();
         if (this.previousDraw == null
             || pipeline != this.previousPipeline
+            || pipeline.getPrimitiveTopology().connectedPrimitives // Neo: flush elements with connected primitives individually
             || this.scissorChanged(scissorArea, this.previousScissorArea)
             || !textureSetup.equals(this.previousTextureSetup)) {
             this.previousPipeline = pipeline;
@@ -292,14 +_,31 @@
 
     private void preparePictureInPicture() {
         int guiScale = Minecraft.getInstance().gameRenderer.gameRenderState().windowRenderState.guiScale;
-        this.renderState.forEachPictureInPicture(pictureInPictureState -> this.preparePictureInPictureState(pictureInPictureState, guiScale));
+        this.pictureInPictureRenderStatesScratch.clear();
+        this.renderState.forEachPictureInPicture(state -> {
+            if (this.preparePictureInPictureState(state, guiScale, true)) {
+                this.pictureInPictureRenderStatesScratch.add(state);
+            }
+        });
+        this.renderState.forEachPictureInPicture(state -> {
+            if (this.pictureInPictureRenderStatesScratch.add(state)) {
+                this.preparePictureInPictureState(state, guiScale, false);
+            }
+        });
+        this.pictureInPictureRenderStatesScratch.clear();
     }
 
-    private <T extends PictureInPictureRenderState> void preparePictureInPictureState(T picturesInPictureState, int guiScale) {
-        PictureInPictureRenderer<T> renderer = (PictureInPictureRenderer<T>)this.pictureInPictureRenderers.get(picturesInPictureState.getClass());
+    private <T extends PictureInPictureRenderState> boolean preparePictureInPictureState(T picturesInPictureState, int guiScale, boolean firstPass) {
+        var pool = (net.neoforged.neoforge.client.gui.PictureInPictureRendererPool<T>)this.pictureInPictureRendererPools.get(picturesInPictureState.getClass());
+        if (pool == null) {
+            return false;
+        }
+        PictureInPictureRenderer<T> renderer = pool.get(picturesInPictureState, guiScale, firstPass);
         if (renderer != null) {
             renderer.prepare(picturesInPictureState, this.renderState, this.featureRenderDispatcher, guiScale);
+            return true;
         }
+        return false;
     }
 
     private void submitBlitFromItemAtlas(GuiItemRenderState itemState, GuiItemAtlas.SlotView slotView) {
@@ -427,7 +_,7 @@
             this.itemAtlas = null;
         }
 
-        this.pictureInPictureRenderers.values().forEach(PictureInPictureRenderer::close);
+        this.pictureInPictureRendererPools.values().forEach(net.neoforged.neoforge.client.gui.PictureInPictureRendererPool::close);
         this.guiProjectionMatrixBuffer.close();
         this.oversizedItemRenderers.values().forEach(PictureInPictureRenderer::close);
         this.cubeMap.close();