1 files changed, 197 insertions, 0 deletions
diff --git a/src/main/kotlin/gui/entity/EntityRenderer.kt b/src/main/kotlin/gui/entity/EntityRenderer.kt
new file mode 100644
index 0000000..8c7428d
--- /dev/null
+++ b/src/main/kotlin/gui/entity/EntityRenderer.kt
@@ -0,0 +1,197 @@
+
+package moe.nea.firmament.gui.entity
+
+import com.google.gson.Gson
+import com.google.gson.JsonArray
+import com.google.gson.JsonObject
+import org.apache.logging.log4j.LogManager
+import org.joml.Quaternionf
+import org.joml.Vector3f
+import kotlin.math.atan
+import net.minecraft.client.gui.DrawContext
+import net.minecraft.client.gui.screen.ingame.InventoryScreen
+import net.minecraft.entity.Entity
+import net.minecraft.entity.EntityType
+import net.minecraft.entity.LivingEntity
+import net.minecraft.util.Identifier
+import moe.nea.firmament.util.MC
+import moe.nea.firmament.util.assertNotNullOr
+import moe.nea.firmament.util.iterate
+import moe.nea.firmament.util.openFirmamentResource
+import moe.nea.firmament.util.render.enableScissorWithTranslation
+
+object EntityRenderer {
+    val fakeWorld = FakeWorld()
+    private fun <T : Entity> t(entityType: EntityType<T>): () -> T {
+        return { entityType.create(fakeWorld)!! }
+    }
+
+    val entityIds: Map<String, () -> LivingEntity> = mapOf(
+        "Zombie" to t(EntityType.ZOMBIE),
+        "Chicken" to t(EntityType.CHICKEN),
+        "Slime" to t(EntityType.SLIME),
+        "Wolf" to t(EntityType.WOLF),
+        "Skeleton" to t(EntityType.SKELETON),
+        "Creeper" to t(EntityType.CREEPER),
+        "Ocelot" to t(EntityType.OCELOT),
+        "Blaze" to t(EntityType.BLAZE),
+        "Rabbit" to t(EntityType.RABBIT),
+        "Sheep" to t(EntityType.SHEEP),
+        "Horse" to t(EntityType.HORSE),
+        "Eisengolem" to t(EntityType.IRON_GOLEM),
+        "Silverfish" to t(EntityType.SILVERFISH),
+        "Witch" to t(EntityType.WITCH),
+        "Endermite" to t(EntityType.ENDERMITE),
+        "Snowman" to t(EntityType.SNOW_GOLEM),
+        "Villager" to t(EntityType.VILLAGER),
+        "Guardian" to t(EntityType.GUARDIAN),
+        "ArmorStand" to t(EntityType.ARMOR_STAND),
+        "Squid" to t(EntityType.SQUID),
+        "Bat" to t(EntityType.BAT),
+        "Spider" to t(EntityType.SPIDER),
+        "CaveSpider" to t(EntityType.CAVE_SPIDER),
+        "Pigman" to t(EntityType.ZOMBIFIED_PIGLIN),
+        "Ghast" to t(EntityType.GHAST),
+        "MagmaCube" to t(EntityType.MAGMA_CUBE),
+        "Wither" to t(EntityType.WITHER),
+        "Enderman" to t(EntityType.ENDERMAN),
+        "Mooshroom" to t(EntityType.MOOSHROOM),
+        "WitherSkeleton" to t(EntityType.WITHER_SKELETON),
+        "Cow" to t(EntityType.COW),
+        "Dragon" to t(EntityType.ENDER_DRAGON),
+        "Player" to { makeGuiPlayer(fakeWorld) },
+        "Pig" to t(EntityType.PIG),
+        "Giant" to t(EntityType.GIANT),
+    )
+    val entityModifiers: Map<String, EntityModifier> = mapOf(
+        "playerdata" to ModifyPlayerSkin,
+        "equipment" to ModifyEquipment,
+        "riding" to ModifyRiding,
+        "charged" to ModifyCharged,
+        "witherdata" to ModifyWither,
+        "invisible" to ModifyInvisible,
+        "age" to ModifyAge,
+        "horse" to ModifyHorse,
+        "name" to ModifyName,
+    )
+
+    val logger = LogManager.getLogger("Firmament.Entity")
+    fun applyModifiers(entityId: String, modifiers: List<JsonObject>): LivingEntity? {
+        val entityType = assertNotNullOr(entityIds[entityId]) {
+            logger.error("Could not create entity with id $entityId")
+            return null
+        }
+        var entity = entityType()
+        for (modifierJson in modifiers) {
+            val modifier = assertNotNullOr(modifierJson["type"]?.asString?.let(entityModifiers::get)) {
+                logger.error("Unknown modifier $modifierJson")
+                return null
+            }
+            entity = modifier.apply(entity, modifierJson)
+        }
+        return entity
+    }
+
+    fun constructEntity(info: JsonObject): LivingEntity? {
+        val modifiers = (info["modifiers"] as JsonArray?)?.map { it.asJsonObject } ?: emptyList()
+        val entityType = assertNotNullOr(info["entity"]?.asString) {
+            logger.error("Missing entity type on entity object")
+            return null
+        }
+        return applyModifiers(entityType, modifiers)
+    }
+
+    private val gson = Gson()
+    fun constructEntity(location: Identifier): LivingEntity? {
+        return constructEntity(
+            gson.fromJson(
+                location.openFirmamentResource().bufferedReader(), JsonObject::class.java
+            )
+        )
+    }
+
+    fun renderEntity(
+        entity: LivingEntity,
+        renderContext: DrawContext,
+        posX: Int,
+        posY: Int,
+        mouseX: Float,
+        mouseY: Float
+    ) {
+        var bottomOffset = 0.0F
+        var currentEntity = entity
+        val maxSize = entity.iterate { it.firstPassenger as? LivingEntity }
+            .map { it.height }
+            .sum()
+        while (true) {
+            currentEntity.age = MC.player?.age ?: 0
+            drawEntity(
+                renderContext,
+                posX,
+                posY,
+                posX + 50,
+                posY + 80,
+                minOf(2F / maxSize, 1F) * 30,
+                -bottomOffset,
+                mouseX,
+                mouseY,
+                currentEntity
+            )
+            val next = currentEntity.firstPassenger as? LivingEntity ?: break
+            bottomOffset += currentEntity.getPassengerRidingPos(next).y.toFloat() * 0.75F
+            currentEntity = next
+        }
+    }
+
+
+    fun drawEntity(
+        context: DrawContext,
+        x1: Int,
+        y1: Int,
+        x2: Int,
+        y2: Int,
+        size: Float,
+        bottomOffset: Float,
+        mouseX: Float,
+        mouseY: Float,
+        entity: LivingEntity
+    ) {
+        context.enableScissorWithTranslation(x1.toFloat(), y1.toFloat(), x2.toFloat(), y2.toFloat())
+        val centerX = (x1 + x2) / 2f
+        val centerY = (y1 + y2) / 2f
+        val targetYaw = atan(((centerX - mouseX) / 40.0f).toDouble()).toFloat()
+        val targetPitch = atan(((centerY - mouseY) / 40.0f).toDouble()).toFloat()
+        val rotateToFaceTheFront = Quaternionf().rotateZ(Math.PI.toFloat())
+        val rotateToFaceTheCamera = Quaternionf().rotateX(targetPitch * 20.0f * (Math.PI.toFloat() / 180))
+        rotateToFaceTheFront.mul(rotateToFaceTheCamera)
+        val oldBodyYaw = entity.bodyYaw
+        val oldYaw = entity.yaw
+        val oldPitch = entity.pitch
+        val oldPrevHeadYaw = entity.prevHeadYaw
+        val oldHeadYaw = entity.headYaw
+        entity.bodyYaw = 180.0f + targetYaw * 20.0f
+        entity.yaw = 180.0f + targetYaw * 40.0f
+        entity.pitch = -targetPitch * 20.0f
+        entity.headYaw = entity.yaw
+        entity.prevHeadYaw = entity.yaw
+        val vector3f = Vector3f(0.0f, entity.height / 2.0f + bottomOffset, 0.0f)
+        InventoryScreen.drawEntity(
+            context,
+            centerX,
+            centerY,
+            size,
+            vector3f,
+            rotateToFaceTheFront,
+            rotateToFaceTheCamera,
+            entity
+        )
+        entity.bodyYaw = oldBodyYaw
+        entity.yaw = oldYaw
+        entity.pitch = oldPitch
+        entity.prevHeadYaw = oldPrevHeadYaw
+        entity.headYaw = oldHeadYaw
+        context.disableScissor()
+    }
+
+
+}