fix old skins (1.7)

Yes, they are still widely used on modded servers. They are not flipped yet. so the test will fail

src/integration-test/kotlin/de/bixilon/minosoft/gui/rendering/system/base/texture/skin/SkinManagerTest.kt

@@ -0,0 +1,47 @@
+/*
+ * 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.gui.rendering.system.base.texture.skin
+
+import de.bixilon.kotlinglm.vec2.Vec2i
+import de.bixilon.minosoft.gui.rendering.system.base.texture.data.TextureData
+import de.bixilon.minosoft.gui.rendering.textures.TextureUtil.readTexture
+import de.bixilon.minosoft.test.IT
+import org.testng.Assert.assertEquals
+import org.testng.annotations.Test
+
+@Test(groups = ["rendering", "textures"])
+class SkinManagerTest {
+    val skin = IT.OBJENESIS.newInstance(SkinManager::class.java)
+    val readSkin = SkinManager::class.java.getDeclaredMethod("readSkin", ByteArray::class.java).apply { isAccessible = true }
+
+
+    private fun ByteArray.readSkin(): TextureData {
+        return readSkin.invoke(skin, this) as TextureData
+    }
+
+    fun `automatically detect and fix legacy skin`() {
+        val old = SkinManager::class.java.getResourceAsStream("/skins/7af7c07d1ded61b1d3312685b32e4568ffdda762ec8d808895cc329a93d606e0.png").readAllBytes().readSkin()
+        val expected = SkinManager::class.java.getResourceAsStream("/skins/7af7c07d1ded61b1d3312685b32e4568ffdda762ec8d808895cc329a93d606e0_fixed.png")!!.readTexture()
+
+        assertEquals(old.size, Vec2i(64, 64)) // fixed size
+        assertEquals(expected.size, Vec2i(64, 64))
+
+        old.buffer.rewind()
+        expected.buffer.rewind()
+
+        // TextureUtil.dump(File("/home/moritz/test.png"), old.size, old.buffer, true, false)
+        assertEquals(old.buffer, expected.buffer)
+    }
+
+}

src/main/java/de/bixilon/minosoft/gui/rendering/gui/atlas/textures/AtlasTexture.kt

@@ -22,6 +22,7 @@ import de.bixilon.minosoft.gui.rendering.system.base.texture.array.TextureArrayP
 import de.bixilon.minosoft.gui.rendering.system.base.texture.data.TextureData
 import de.bixilon.minosoft.gui.rendering.system.base.texture.texture.Texture
 import de.bixilon.minosoft.gui.rendering.system.base.texture.texture.TextureRenderData
+import de.bixilon.minosoft.gui.rendering.textures.TextureUtil
 import de.bixilon.minosoft.gui.rendering.textures.properties.ImageProperties
 
 class AtlasTexture(
@@ -42,18 +43,7 @@ class AtlasTexture(
     fun request(size: Vec2i): Vec2i? = null
 
     fun put(offset: Vec2i, source: TextureData, start: Vec2i, size: Vec2i): CodeTexturePart {
-        for (y in 0 until size.y) {
-            for (x in 0 until size.x) {
-                val sourceOffset = ((start.y + y) * source.size.x + (start.x + x)) * 4
-                val destinationOffset = ((offset.y + y) * this.size.x + (offset.x + x)) * 4
-
-                data.buffer.put(destinationOffset + 0, source.buffer.get(sourceOffset + 0))
-                data.buffer.put(destinationOffset + 1, source.buffer.get(sourceOffset + 1))
-                data.buffer.put(destinationOffset + 2, source.buffer.get(sourceOffset + 2))
-                data.buffer.put(destinationOffset + 3, source.buffer.get(sourceOffset + 3))
-            }
-        }
-
+        TextureUtil.copy(start, source, offset, this.data, size)
 
         return CodeTexturePart(this, pixel * offset, pixel * (offset + size), size)
     }

src/main/java/de/bixilon/minosoft/gui/rendering/system/base/texture/skin/SkinManager.kt

@@ -13,6 +13,7 @@
 
 package de.bixilon.minosoft.gui.rendering.system.base.texture.skin
 
+import de.bixilon.kotlinglm.vec2.Vec2i
 import de.bixilon.kutil.exception.ExceptionUtil.catchAll
 import de.bixilon.minosoft.assets.AssetsManager
 import de.bixilon.minosoft.config.profile.profiles.account.AccountProfileManager
@@ -21,7 +22,11 @@ import de.bixilon.minosoft.data.entities.entities.player.PlayerEntity
 import de.bixilon.minosoft.data.entities.entities.player.local.LocalPlayerEntity
 import de.bixilon.minosoft.data.entities.entities.player.properties.PlayerProperties
 import de.bixilon.minosoft.gui.rendering.system.base.texture.TextureManager
+import de.bixilon.minosoft.gui.rendering.system.base.texture.data.TextureData
 import de.bixilon.minosoft.gui.rendering.system.base.texture.skin.vanilla.DefaultSkinProvider
+import de.bixilon.minosoft.gui.rendering.textures.TextureUtil
+import de.bixilon.minosoft.gui.rendering.textures.TextureUtil.readTexture
+import java.io.ByteArrayInputStream
 import java.util.*
 
 class SkinManager(private val textureManager: TextureManager) {
@@ -51,7 +56,7 @@ class SkinManager(private val textureManager: TextureManager) {
 
     private fun getSkin(uuid: UUID, properties: PlayerProperties?, async: Boolean = true): PlayerSkin? {
         val texture = properties?.textures?.skin ?: return default[uuid]
-        return PlayerSkin(textureManager.dynamicTextures.pushRaw(texture.getHash(), async) { texture.read() }, default[uuid]?.texture, texture.metadata.model)
+        return PlayerSkin(textureManager.dynamicTextures.push(texture.getHash(), async) { texture.read().readSkin() }, default[uuid]?.texture, texture.metadata.model)
     }
 
     fun getSkin(player: PlayerEntity, properties: PlayerProperties? = null, fetch: Boolean = true, async: Boolean = true): PlayerSkin? {
@@ -67,4 +72,20 @@ class SkinManager(private val textureManager: TextureManager) {
 
         return getSkin(uuid, properties ?: if (fetch) catchAll { PlayerProperties.fetch(uuid) } else null, async)
     }
+
+    private fun ByteArray.readSkin(): TextureData {
+        val data = ByteArrayInputStream(this).readTexture()
+        if (data.size.y != 32) return data
+
+        val next = TextureData(Vec2i(64))
+        data.buffer.rewind()
+        next.buffer.put(data.buffer)
+
+        TextureUtil.copy(Vec2i(0, 16), next, Vec2i(16, 48), next, Vec2i(16, 16)) // leg [0, 16][16,16] to left leg [16, 48]
+        TextureUtil.copy(Vec2i(40, 16), next, Vec2i(32, 48), next, Vec2i(16, 16)) // arm [40, 16] to left arm [32, 48]
+
+        // TODO: flip
+
+        return next
+    }
 }

src/main/java/de/bixilon/minosoft/gui/rendering/textures/TextureUtil.kt

@@ -123,4 +123,18 @@ object TextureUtil {
 
         ImageIO.write(bufferedImage, "png", file)
     }
+
+    fun copy(sourceOffset: Vec2i, source: TextureData, targetOffset: Vec2i, target: TextureData, size: Vec2i) {
+        for (y in 0 until size.y) {
+            for (x in 0 until size.x) {
+                val sofs = ((sourceOffset.y + y) * source.size.x + (sourceOffset.x + x)) * 4
+                val dofs = ((targetOffset.y + y) * target.size.x + (targetOffset.x + x)) * 4
+
+                target.buffer.put(dofs + 0, source.buffer.get(sofs + 0))
+                target.buffer.put(dofs + 1, source.buffer.get(sofs + 1))
+                target.buffer.put(dofs + 2, source.buffer.get(sofs + 2))
+                target.buffer.put(dofs + 3, source.buffer.get(sofs + 3))
+            }
+        }
+    }
 }