[Feature] Speed modified Elytra API

src/main/java/org/betterx/bclib/items/elytra/BCLElytraItem.java

@@ -0,0 +1,11 @@
+package org.betterx.bclib.items.elytra;
+
+import net.minecraft.resources.ResourceLocation;
+
+import net.fabricmc.fabric.api.entity.event.v1.FabricElytraItem;
+
+public interface BCLElytraItem extends FabricElytraItem {
+    ResourceLocation getModelTexture();
+
+    double getMovementFactor();
+}

src/main/java/org/betterx/bclib/mixin/common/elytra/LivingEntityMixin.java

@@ -0,0 +1,35 @@
+package org.betterx.bclib.mixin.common.elytra;
+
+import org.betterx.bclib.items.elytra.BCLElytraItem;
+
+import net.minecraft.world.entity.EquipmentSlot;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.phys.Vec3;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.ModifyArg;
+import org.spongepowered.asm.mixin.injection.Slice;
+
+@Mixin(value = LivingEntity.class, priority = 199)
+public abstract class LivingEntityMixin {
+    @Shadow
+    public abstract ItemStack getItemBySlot(EquipmentSlot equipmentSlot);
+
+    @ModifyArg(
+            method = "travel",
+            slice = @Slice(
+                    from = @At(value = "INVOKE", target = "Lnet/minecraft/world/entity/LivingEntity;isFallFlying()Z"),
+                    to = @At(value = "INVOKE:LAST", target = "Lnet/minecraft/world/entity/LivingEntity;setSharedFlag(IZ)V")
+            ),
+            at = @At(value = "INVOKE", target = "Lnet/minecraft/world/entity/LivingEntity;setDeltaMovement(Lnet/minecraft/world/phys/Vec3;)V")
+    )
+    public Vec3 be_travel(Vec3 moveDelta) {
+        ItemStack itemStack = getItemBySlot(EquipmentSlot.CHEST);
+        double movementFactor = ((BCLElytraItem) itemStack.getItem()).getMovementFactor();
+        moveDelta = moveDelta.multiply(movementFactor, 1.0D, movementFactor);
+        return moveDelta;
+    }
+}

src/main/resources/bclib.mixins.common.json

@@ -47,6 +47,7 @@
     "WorldGenRegionMixin",
     "WorldOpenFlowsMixin",
     "WorldPresetsBootstrapMixin",
+    "elytra.LivingEntityMixin",
     "shears.BeehiveBlockMixin",
     "shears.DiggingEnchantmentMixin",
     "shears.ItemPredicateBuilderMixin",