fix flip easter egg

src/main/java/de/bixilon/minosoft/gui/rendering/entities/easteregg/EntityEasterEggs.kt

@@ -21,9 +21,11 @@ import de.bixilon.minosoft.data.entities.entities.player.SkinParts
 
 object EntityEasterEggs {
     private val FLIPPED = setOf("Dinnerbone", "Grumm")
-    val FLIP_ROTATION = Vec3(0.0f, 0.0f, 180.0f.rad)
+    val FLIP_ROTATION = Vec3(0, 0.0f, 180.0f.rad)
+    const val FLIP_ENABLED = true
 
     fun Entity.isFlipped(): Boolean {
+        if (!FLIP_ENABLED) return false
         var name = this.customName?.message
         if (name == null && this is PlayerEntity) {
             name = additional.name

src/main/java/de/bixilon/minosoft/gui/rendering/entities/feature/SkeletalFeature.kt

@@ -17,6 +17,7 @@ import de.bixilon.kotlinglm.func.rad
 import de.bixilon.kotlinglm.vec3.Vec3
 import de.bixilon.kotlinglm.vec3.Vec3d
 import de.bixilon.minosoft.data.entities.EntityRotation
+import de.bixilon.minosoft.gui.rendering.entities.easteregg.EntityEasterEggs.isFlipped
 import de.bixilon.minosoft.gui.rendering.entities.renderer.EntityRenderer
 import de.bixilon.minosoft.gui.rendering.skeletal.baked.BakedSkeletalModel
 import de.bixilon.minosoft.gui.rendering.skeletal.instance.SkeletalInstance
@@ -36,7 +37,7 @@ open class SkeletalFeature(
 
     protected open fun updatePosition() {
         val renderInfo = renderer.info
-        val yaw = renderInfo.rotation.yaw
+        var yaw = renderInfo.rotation.yaw
         val position = renderInfo.position
 
         var changes = 0
@@ -49,7 +50,9 @@ open class SkeletalFeature(
             this.yaw = yaw
         }
         if (changes == 0) return
-
+        if (renderer.entity.isFlipped()) {
+            yaw *= -1.0f
+        }
         val rotation = Vec3(0.0f, (EntityRotation.HALF_CIRCLE_DEGREE - yaw).rad, 0.0f)
         instance.update(rotation, renderer.matrix)
     }

src/main/java/de/bixilon/minosoft/gui/rendering/entities/model/human/animator/HeadPosition.kt

@@ -15,6 +15,7 @@ package de.bixilon.minosoft.gui.rendering.entities.model.human.animator
 
 import de.bixilon.kotlinglm.func.rad
 import de.bixilon.kotlinglm.vec3.Vec3
+import de.bixilon.minosoft.gui.rendering.entities.easteregg.EntityEasterEggs.isFlipped
 import de.bixilon.minosoft.gui.rendering.entities.model.human.HumanModel
 import de.bixilon.minosoft.gui.rendering.skeletal.instance.TransformInstance
 import de.bixilon.minosoft.gui.rendering.util.mat.mat4.Mat4Util.rotateRadAssign
@@ -31,6 +32,9 @@ class HeadPosition(
 
         val pitch = info.rotation.pitch
         this.rotation.x = -pitch.rad
+        if (model.renderer.entity.isFlipped()) {
+            this.rotation.x = -this.rotation.x // TODO: not 100% correct
+        }
         transform.value
             .translateAssign(transform.pivot)
             .rotateRadAssign(this.rotation)

src/main/java/de/bixilon/minosoft/gui/rendering/entities/renderer/EntityRenderer.kt

@@ -25,7 +25,7 @@ import de.bixilon.minosoft.gui.rendering.entities.feature.EntityRenderFeature
 import de.bixilon.minosoft.gui.rendering.entities.feature.FeatureManager
 import de.bixilon.minosoft.gui.rendering.entities.hitbox.HitboxFeature
 import de.bixilon.minosoft.gui.rendering.util.mat.mat4.Mat4Util.reset
-import de.bixilon.minosoft.gui.rendering.util.mat.mat4.Mat4Util.rotateDegreesAssign
+import de.bixilon.minosoft.gui.rendering.util.mat.mat4.Mat4Util.rotateRadAssign
 import de.bixilon.minosoft.util.interpolate.Interpolator
 
 abstract class EntityRenderer<E : Entity>(
@@ -53,7 +53,9 @@ abstract class EntityRenderer<E : Entity>(
         matrix.translateAssign(position)
 
         if (entity.isFlipped()) {
-            matrix.rotateDegreesAssign(FLIP_ROTATION)
+            matrix
+                .translateAssign(Vec3(0.0f, entity.dimensions.y + 0.2f, 0.0f))
+                .rotateRadAssign(FLIP_ROTATION)
         }
     }
 

src/main/java/de/bixilon/minosoft/gui/rendering/skeletal/instance/SkeletalInstance.kt

@@ -60,14 +60,15 @@ class SkeletalInstance(
 
     fun update(position: Vec3, rotation: Vec3, pivot: Vec3 = Vec3.EMPTY_INSTANCE, matrix: Mat4? = null) {
         this.matrix.reset()
-        if (matrix != null) {
-            this.matrix = this.matrix * matrix
-        }
         this.matrix
             .translateAssign(position)
             .translateAssign(pivot)
             .rotateRadAssign(rotation)
             .translateAssign(-pivot)
+
+        if (matrix != null) {
+            this.matrix = matrix * this.matrix
+        }
     }
 
     fun update(rotation: Vec3, matrix: Mat4? = null) {