Re-license some external patches under the MPL2

The author has requested that their changes continue to
be distributed under a copyleft license. After discussion,
we agreed that MPL2 is the best option for allowing Sodium
to continue using the patches, and for ensuring that others
must distribute their changes if the patches are modified.

README.md

@@ -78,5 +78,5 @@ repositories.
 
 ## 📜 License
 
-Except where otherwise stated, the content of this repository is provided under the [Polyform Shield 1.0.0](LICENSE.md)
-license by [JellySquid](https://jellysquid.me).
+Except where otherwise stated (see [third-party license notices](thirdparty/NOTICE.txt)), the content of this repository is provided
+under the [Polyform Shield 1.0.0](LICENSE.md) license by [JellySquid](https://jellysquid.me).

common/src/main/java/net/caffeinemc/mods/sodium/mixin/features/textures/mipmaps/MipmapGeneratorMixin.java

@@ -1,3 +1,10 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * Original source: https://github.com/IrisShaders/Iris/blob/41095ac23ea0add664afd1b85c414d1f1ed94066/src/main/java/net/coderbot/iris/mixin/bettermipmaps/MixinMipmapGenerator.java
+ */
 package net.caffeinemc.mods.sodium.mixin.features.textures.mipmaps;
 
 import net.caffeinemc.mods.sodium.client.util.color.ColorSRGB;
@@ -23,8 +30,6 @@
  *         cutout textures, this results in a lot of pixels with high alpha values and dark colors, causing visual
  *         artifacts.</ul>
  * </li>
- *
- * This Mixin is ported from Iris at <a href="https://github.com/IrisShaders/Iris/blob/41095ac23ea0add664afd1b85c414d1f1ed94066/src/main/java/net/coderbot/iris/mixin/bettermipmaps/MixinMipmapGenerator.java">MixinMipmapGenerator</a>.
  */
 @Mixin(MipmapGenerator.class)
 public class MipmapGeneratorMixin {

common/src/main/java/net/caffeinemc/mods/sodium/mixin/features/textures/mipmaps/SpriteContentsMixin.java

@@ -1,3 +1,10 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * Original source: https://github.com/IrisShaders/Iris/blob/41095ac23ea0add664afd1b85c414d1f1ed94066/src/main/java/net/coderbot/iris/mixin/bettermipmaps/MixinTextureAtlasSprite.java
+ */
 package net.caffeinemc.mods.sodium.mixin.features.textures.mipmaps;
 
 import com.mojang.blaze3d.platform.NativeImage;
@@ -16,9 +23,6 @@
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Redirect;
 
-/**
- * This Mixin is ported from Iris at <a href="https://github.com/IrisShaders/Iris/blob/41095ac23ea0add664afd1b85c414d1f1ed94066/src/main/java/net/coderbot/iris/mixin/bettermipmaps/MixinTextureAtlasSprite.java">MixinTextureAtlasSprite</a>.
- */
 @Mixin(SpriteContents.class)
 public class SpriteContentsMixin {
     @Mutable

thirdparty/NOTICE.txt

@@ -0,0 +1,24 @@
+Third-Party License Notice
+=======================================
+
+This project contains source code based upon, or includes source code from, the following third-party
+projects.
+
+The complete text for each software license can be found in the directory "thirdparty/licenses".
+
+* lodborg's interval tree library for Java
+  * Copyright (c) 2016 lodborg
+  * License: MIT
+  * Original Source
+    * https://github.com/lodborg/interval-tree/tree/v1.0.0
+  * Files:
+    * common/src/main/java/net/caffeinemc/mods/sodium/client/util/interval_tree
+
+* coderbot's mip-map generator patches for Minecraft
+  * Copyright (c) 2021 Coderbot
+  * License: Mozilla Public License (MPL2)
+  * Original Source:
+    * https://github.com/IrisShaders/Iris/tree/41095ac23ea0add664afd1b85c414d1f1ed94066/src/main/java/net/coderbot/iris/mixin/bettermipmaps
+  * Files:
+    * common/src/main/java/net/caffeinemc/mods/sodium/mixin/features/textures/mipmaps
+

thirdparty/licenses/LICENSE-MIT.txt

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) [year] [fullname]
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.