Add hand-specific render event

src/main/java/net/minecraftforge/client/ForgeHooksClient.java

@@ -79,6 +79,7 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.BlockRenderLayer;
 import net.minecraft.util.EnumFacing;
+import net.minecraft.util.EnumHand;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.MathHelper;
@@ -97,6 +98,7 @@ import net.minecraftforge.client.event.ModelBakeEvent;
 import net.minecraftforge.client.event.MouseEvent;
 import net.minecraftforge.client.event.RenderGameOverlayEvent;
 import net.minecraftforge.client.event.RenderHandEvent;
+import net.minecraftforge.client.event.RenderHandEventSpecific;
 import net.minecraftforge.client.event.RenderWorldLastEvent;
 import net.minecraftforge.client.event.ScreenshotEvent;
 import net.minecraftforge.client.event.TextureStitchEvent;
@@ -168,6 +170,11 @@ public class ForgeHooksClient
         return MinecraftForge.EVENT_BUS.post(new RenderHandEvent(context, partialTicks, renderPass));
     }
 
+    public static boolean renderFirstPersonHandSpecific(EnumHand hand, float partialTicks, float interpPitch, float swingProgress, float equipProgress, ItemStack stack)
+    {
+        return MinecraftForge.EVENT_BUS.post(new RenderHandEventSpecific(hand, partialTicks, interpPitch, swingProgress, equipProgress, stack));
+    }
+
     public static void onTextureStitchedPre(TextureMap map)
     {
         MinecraftForge.EVENT_BUS.post(new TextureStitchEvent.Pre(map));

src/main/java/net/minecraftforge/client/event/RenderHandEvent.java

@@ -23,6 +23,12 @@ import net.minecraftforge.fml.common.eventhandler.Cancelable;
 import net.minecraftforge.fml.common.eventhandler.Event;
 import net.minecraft.client.renderer.RenderGlobal;
 
+/**
+ * This event is fired on {@link net.minecraftforge.common.MinecraftForge#EVENT_BUS}
+ * before both hands are rendered.
+ * Canceling this event prevents either hand from being rendered,
+ * and prevents {@link RenderHandEventSpecific} from firing.
+ */
 @Cancelable
 public class RenderHandEvent extends Event
 {

src/main/java/net/minecraftforge/client/event/RenderHandEventSpecific.java

@@ -0,0 +1,75 @@
+package net.minecraftforge.client.event;
+
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.EnumHand;
+import net.minecraftforge.fml.common.eventhandler.Event;
+
+import javax.annotation.Nullable;
+
+/**
+ * This event is fired on the {@link net.minecraftforge.common.MinecraftForge#EVENT_BUS}
+ * whenever a hand is rendered in first person.
+ * Canceling the event causes the hand to not render.
+ */
+public class RenderHandEventSpecific extends Event
+{
+    private final EnumHand hand;
+    private final float partialTicks;
+    private final float interpolatedPitch;
+    private final float swingProgress;
+    private final float equipProgress;
+    private final ItemStack stack;
+
+    public RenderHandEventSpecific(EnumHand hand, float partialTicks, float interpolatedPitch, float swingProgress, float equipProgress, ItemStack stack)
+    {
+        this.hand = hand;
+        this.partialTicks = partialTicks;
+        this.interpolatedPitch = interpolatedPitch;
+        this.swingProgress = swingProgress;
+        this.equipProgress = equipProgress;
+        this.stack = stack;
+    }
+
+    public EnumHand getHand()
+    {
+        return hand;
+    }
+
+    public float getPartialTicks()
+    {
+        return partialTicks;
+    }
+
+    /**
+     * @return The interpolated pitch of the player entity
+     */
+    public float getInterpolatedPitch()
+    {
+        return interpolatedPitch;
+    }
+
+    /**
+     * @return The swing progress of the hand being rendered
+     */
+    public float getSwingProgress()
+    {
+        return swingProgress;
+    }
+
+    /**
+     * @return The progress of the equip animation. 1.0 is fully equipped.
+     */
+    public float getEquipProgress()
+    {
+        return equipProgress;
+    }
+
+    /**
+     * @return The ItemStack to be rendered, or null.
+     */
+    @Nullable
+    public ItemStack getItemStack()
+    {
+        return stack;
+    }
+}