feat: Highlight century cake slice players

src/main/kotlin/util/MC.kt

@@ -7,11 +7,13 @@ import net.minecraft.client.gui.hud.InGameHud
 import net.minecraft.client.gui.screen.Screen
 import net.minecraft.client.gui.screen.ingame.HandledScreen
 import net.minecraft.client.network.ClientPlayerEntity
+import net.minecraft.client.render.GameRenderer
 import net.minecraft.client.render.WorldRenderer
 import net.minecraft.client.render.item.ItemRenderer
 import net.minecraft.client.world.ClientWorld
 import net.minecraft.entity.Entity
 import net.minecraft.item.Item
+import net.minecraft.item.ItemStack
 import net.minecraft.network.packet.c2s.play.CommandExecutionC2SPacket
 import net.minecraft.registry.BuiltinRegistries
 import net.minecraft.registry.RegistryKeys
@@ -85,6 +87,7 @@ object MC {
 	inline val resourceManager get() = (instance.resourceManager as ReloadableResourceManagerImpl)
 	inline val itemRenderer: ItemRenderer get() = instance.itemRenderer
 	inline val worldRenderer: WorldRenderer get() = instance.worldRenderer
+	inline val gameRenderer: GameRenderer get() = instance.gameRenderer
 	inline val networkHandler get() = player?.networkHandler
 	inline val instance get() = MinecraftClient.getInstance()
 	inline val keyboard get() = instance.keyboard
@@ -96,6 +99,7 @@ object MC {
 	inline val soundManager get() = instance.soundManager
 	inline val player: ClientPlayerEntity? get() = TestUtil.unlessTesting { instance.player }
 	inline val camera: Entity? get() = instance.cameraEntity
+	inline val stackInHand: ItemStack? get() = player?.inventory?.mainHandStack
 	inline val guiAtlasManager get() = instance.guiAtlasManager
 	inline val world: ClientWorld? get() = TestUtil.unlessTesting { instance.world }
 	inline val playerName: String? get() = player?.name?.unformattedString

src/main/kotlin/util/render/TintedOverlayTexture.kt

@@ -0,0 +1,44 @@
+package moe.nea.firmament.util.render
+
+import com.mojang.blaze3d.platform.GlConst
+import com.mojang.blaze3d.systems.RenderSystem
+import me.shedaniel.math.Color
+import net.minecraft.client.render.OverlayTexture
+import net.minecraft.util.math.ColorHelper
+import moe.nea.firmament.util.ErrorUtil
+
+class TintedOverlayTexture : OverlayTexture() {
+	companion object {
+		val size = 16
+	}
+
+	private var lastColor: Color? = null
+	fun setColor(color: Color): TintedOverlayTexture {
+		val image = ErrorUtil.notNullOr(texture.image, "Disposed TintedOverlayTexture written to") { return this }
+		if (color == lastColor) return this
+		lastColor = color
+
+		for (i in 0..<size) {
+			for (j in 0..<size) {
+				if (i < 8) {
+					image.setColorArgb(j, i, 0xB2FF0000.toInt())
+				} else {
+					val k = ((1F - j / 15F * 0.75F) * 255F).toInt()
+					image.setColorArgb(j, i, ColorHelper.withAlpha(k, color.color))
+				}
+			}
+		}
+
+		RenderSystem.activeTexture(GlConst.GL_TEXTURE1)
+		texture.bindTexture()
+		texture.setFilter(false, false)
+		texture.setClamp(true)
+		image.upload(0,
+		             0, 0,
+		             0, 0,
+		             image.width, image.height,
+		             false)
+		RenderSystem.activeTexture(GlConst.GL_TEXTURE0)
+		return this
+	}
+}

src/main/kotlin/util/skyblock/SkyBlockItems.kt

@@ -8,4 +8,9 @@ object SkyBlockItems {
 	val DIAMOND = SkyblockId("DIAMOND")
 	val ANCESTRAL_SPADE = SkyblockId("ANCESTRAL_SPADE")
 	val REFORGE_ANVIL = SkyblockId("REFORGE_ANVIL")
+	val SLICE_OF_BLUEBERRY_CAKE = SkyblockId("SLICE_OF_BLUEBERRY_CAKE")
+	val SLICE_OF_CHEESECAKE = SkyblockId("SLICE_OF_CHEESECAKE")
+	val SLICE_OF_GREEN_VELVET_CAKE = SkyblockId("SLICE_OF_GREEN_VELVET_CAKE")
+	val SLICE_OF_RED_VELVET_CAKE = SkyblockId("SLICE_OF_RED_VELVET_CAKE")
+	val SLICE_OF_STRAWBERRY_SHORTCAKE = SkyblockId("SLICE_OF_STRAWBERRY_SHORTCAKE")
 }