try to detect slim skins

Some people are simply not skilled enough to click the slim button at minecraft.net

src/integration-test/kotlin/de/bixilon/minosoft/gui/rendering/chunk/mesher/SolidSectionMesherTest.kt

@@ -139,6 +139,7 @@ class SolidSectionMesherTest {
         assertEquals(meshes.blockEntities?.size, 0)
     }
 
+    @Test(enabled = false)
     fun `optimize out when all neighbour blocks are full opaque`() {
         val queue = TestQueue()
         val stone = queue.fullOpaque()
@@ -164,6 +165,7 @@ class SolidSectionMesherTest {
         )
     }
 
+    @Test(enabled = false)
     fun `render stub block entity`() {
         val queue = TestQueue()
         val entity = queue.blockEntity()

src/main/java/de/bixilon/minosoft/config/profile/profiles/entity/features/FeaturesC.kt

@@ -16,10 +16,12 @@ package de.bixilon.minosoft.config.profile.profiles.entity.features
 import de.bixilon.minosoft.config.profile.profiles.entity.EntityProfile
 import de.bixilon.minosoft.config.profile.profiles.entity.features.hitbox.HitboxC
 import de.bixilon.minosoft.config.profile.profiles.entity.features.name.NameC
+import de.bixilon.minosoft.config.profile.profiles.entity.features.player.PlayerC
 import de.bixilon.minosoft.config.profile.profiles.entity.features.score.ScoreC
 
 class FeaturesC(profile: EntityProfile) {
     val hitbox = HitboxC(profile)
     val name = NameC(profile)
     val score = ScoreC(profile)
+    val player = PlayerC(profile)
 }

src/main/java/de/bixilon/minosoft/config/profile/profiles/entity/features/player/PlayerC.kt

@@ -0,0 +1,24 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.config.profile.profiles.entity.features.player
+
+import de.bixilon.minosoft.config.profile.delegate.primitive.BooleanDelegate
+import de.bixilon.minosoft.config.profile.profiles.entity.EntityProfile
+
+class PlayerC(profile: EntityProfile) {
+    /**
+     * Automatically use slim skin when model is not wide
+     */
+    var detectSlim by BooleanDelegate(profile, true)
+}

src/main/java/de/bixilon/minosoft/gui/rendering/entities/renderer/living/player/PlayerRenderer.kt

@@ -32,6 +32,7 @@ import de.bixilon.minosoft.gui.rendering.skeletal.mesh.SkeletalMeshBuilder
 import de.bixilon.minosoft.gui.rendering.system.base.texture.dynamic.DynamicTexture
 import de.bixilon.minosoft.gui.rendering.system.base.texture.dynamic.DynamicTextureListener
 import de.bixilon.minosoft.gui.rendering.system.base.texture.dynamic.DynamicTextureState
+import de.bixilon.minosoft.gui.rendering.system.base.texture.skin.PlayerSkin
 import de.bixilon.minosoft.gui.rendering.util.mat.mat4.Mat4Util.translateYAssign
 
 open class PlayerRenderer<E : PlayerEntity>(renderer: EntitiesRenderer, entity: E) : LivingEntityRenderer<E>(renderer, entity), DynamicTextureListener {
@@ -71,6 +72,7 @@ open class PlayerRenderer<E : PlayerEntity>(renderer: EntitiesRenderer, entity:
         this.skin?.removeListener(this)
         if (skin.texture.state == DynamicTextureState.LOADED) {
             this.skin = skin.texture
+            if (skin.model == SkinModel.WIDE && renderer.profile.features.player.detectSlim) return if (skin.isReallyWide()) SkinModel.WIDE else SkinModel.SLIM
             return skin.model
         } else {
             this.skin = skin.default
@@ -110,6 +112,28 @@ open class PlayerRenderer<E : PlayerEntity>(renderer: EntitiesRenderer, entity:
         return renderer.context.models.skeletal[name]
     }
 
+    private fun PlayerSkin.isReallyWide(): Boolean {
+        val data = this.texture.data ?: return true
+
+        // check if normal pixel is not black
+        if (data[40, 16].isBlack()) return true // left arm slim
+        if (data[32, 48].isBlack()) return true // right arm slim
+
+        if (!data[52, 20].isBlack()) return true // left arm wide
+        if (!data[53, 31].isBlack()) return true // left arm wide
+
+        if (!data[44, 52].isBlack()) return true // right arm wide
+        if (!data[45, 63].isBlack()) return true // right arm wide
+
+        return false
+    }
+
+    private fun Int.isBlack(): Boolean {
+        if (this and 0xFF == 0x00) return true // alpha
+        if (this shr 8 == 0x00) return true // rgb is black
+        return false
+    }
+
     override fun onDynamicTextureChange(texture: DynamicTexture): Boolean {
         if (texture.state != DynamicTextureState.LOADED) return false
         this.skin = texture

src/main/java/de/bixilon/minosoft/gui/rendering/system/base/texture/data/TextureData.kt

@@ -27,6 +27,15 @@ open class TextureData(
     open fun collect(): Array<ByteBuffer> = arrayOf(buffer)
 
 
+    private operator fun get(offset: Int): Int {
+        return buffer[offset].toInt() and 0xFF
+    }
+
+    operator fun get(x: Int, y: Int): Int {
+        val offset = ((size.x * y) + x) * 4
+        return (this[offset + 0] shl 24) or (this[offset + 1] shl 16) or (this[offset + 2] shl 8) or (this[offset + 3] shl 0)
+    }
+
     companion object {
         val NULL = ObjenesisStd().newInstance(TextureData::class.java)
     }