Revert "Revert "Apply BufferBuilder optimizations via delegate (Caffe…

…ineMC#2241)""

This reverts commit 3621222.

src/api/java/net/caffeinemc/mods/sodium/api/vertex/format/VertexFormatDescription.java

@@ -28,4 +28,9 @@ public interface VertexFormatDescription {
      * start at the byte offset (index * stride).
      */
     int stride();
+
+    /**
+     * Returns whether or not the format is "simple" (has no duplicate elements).
+     */
+    boolean isSimpleFormat();
 }

src/main/java/me/jellysquid/mods/sodium/client/render/vertex/VertexFormatDescriptionImpl.java

@@ -4,8 +4,10 @@
 import net.caffeinemc.mods.sodium.api.vertex.attributes.CommonVertexAttribute;
 import net.caffeinemc.mods.sodium.api.vertex.format.VertexFormatDescription;
 import net.minecraft.client.render.VertexFormat;
+import net.minecraft.client.render.VertexFormats;
 
 import java.util.Arrays;
+import java.util.EnumSet;
 import java.util.NoSuchElementException;
 
 public class VertexFormatDescriptionImpl implements VertexFormatDescription {
@@ -14,11 +16,29 @@ public class VertexFormatDescriptionImpl implements VertexFormatDescription {
 
     private final int[] offsets;
 
+    private final boolean isSimple;
+
     public VertexFormatDescriptionImpl(VertexFormat format, int id) {
         this.id = id;
         this.stride = format.getVertexSizeByte();
 
         this.offsets = getOffsets(format);
+        this.isSimple = checkSimple(format);
+    }
+
+    private static boolean checkSimple(VertexFormat format) {
+        EnumSet<CommonVertexAttribute> attributeSet = EnumSet.noneOf(CommonVertexAttribute.class);
+        var elementList = format.getElements();
+
+        for (int elementIndex = 0; elementIndex < elementList.size(); elementIndex++) {
+            var element = elementList.get(elementIndex);
+            var commonType = CommonVertexAttribute.getCommonType(element);
+            if (element != VertexFormats.PADDING_ELEMENT && (commonType == null || !attributeSet.add(commonType))) {
+                return false;
+            }
+        }
+
+        return true;
     }
 
     public static int[] getOffsets(VertexFormat format) {
@@ -66,4 +86,9 @@ public int id() {
     public int stride() {
         return this.stride;
     }
+
+    @Override
+    public boolean isSimpleFormat() {
+        return this.isSimple;
+    }
 }

src/main/java/me/jellysquid/mods/sodium/client/render/vertex/buffer/ExtendedBufferBuilder.java

@@ -0,0 +1,15 @@
+package me.jellysquid.mods.sodium.client.render.vertex.buffer;
+
+import net.caffeinemc.mods.sodium.api.vertex.buffer.VertexBufferWriter;
+import net.caffeinemc.mods.sodium.api.vertex.format.VertexFormatDescription;
+
+import java.nio.ByteBuffer;
+
+public interface ExtendedBufferBuilder extends VertexBufferWriter {
+    ByteBuffer sodium$getBuffer();
+    int sodium$getElementOffset();
+    void sodium$moveToNextVertex();
+    VertexFormatDescription sodium$getFormatDescription();
+    boolean sodium$usingFixedColor();
+    SodiumBufferBuilder sodium$getDelegate();
+}