[WIP] initial Fabric port

major package refactoring

src/main/kotlin/mods/betterfoliage/chunk/OffsetBlockView.kt

@@ -0,0 +1,50 @@
+package mods.betterfoliage.chunk
+
+import net.minecraft.util.math.BlockPos
+import net.minecraft.world.BlockView
+import net.minecraft.world.ExtendedBlockView
+import net.minecraft.world.LightType
+
+/**
+ * Delegating [IBlockAccess] that fakes a _modified_ location to return values from a _target_ location.
+ * All other locations are handled normally.
+ *
+ * @param[original] the [IBlockAccess] that is delegated to
+ */
+@Suppress("NOTHING_TO_INLINE", "NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS", "HasPlatformType")
+open class OffsetBlockView(open val original: BlockView, val modded: BlockPos, val target: BlockPos) : BlockView {
+    inline fun actualPos(pos: BlockPos) = if (pos != null && pos.x == modded.x && pos.y == modded.y && pos.z == modded.z) target else pos
+
+    override fun getBlockState(pos: BlockPos) = original.getBlockState(actualPos(pos))
+    override fun getBlockEntity(pos: BlockPos) = original.getBlockEntity(actualPos(pos))
+    override fun getFluidState(pos: BlockPos) = original.getFluidState(actualPos(pos))
+}
+
+@Suppress("NOTHING_TO_INLINE", "NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS", "HasPlatformType")
+class OffsetExtBlockView(val original: ExtendedBlockView, val modded: BlockPos, val target: BlockPos) : ExtendedBlockView by original {
+    inline fun actualPos(pos: BlockPos) = if (pos != null && pos.x == modded.x && pos.y == modded.y && pos.z == modded.z) target else pos
+
+    override fun getBlockState(pos: BlockPos) = original.getBlockState(actualPos(pos))
+    override fun getBlockEntity(pos: BlockPos) = original.getBlockEntity(actualPos(pos))
+    override fun getFluidState(pos: BlockPos) = original.getFluidState(actualPos(pos))
+
+    override fun getLightLevel(type: LightType, pos: BlockPos) = original.getLightLevel(type, actualPos(pos))
+    override fun getLightmapIndex(pos: BlockPos, light: Int) = original.getLightmapIndex(actualPos(pos), light)
+    override fun getBiome(pos: BlockPos) = original.getBiome(actualPos(pos))
+}
+
+/**
+ * Temporarily replaces the [IBlockReader] used by this [BlockContext] and the corresponding [ExtendedRenderBlocks]
+ * to use an [OffsetEnvBlockReader] while executing this lambda.
+ *
+ * @param[modded] the _modified_ location
+ * @param[target] the _target_ location
+ * @param[func] the lambda to execute
+ */
+//inline fun <reified T> BlockContext.withOffset(modded: Int3, target: Int3, func: () -> T): T {
+//    val original = reader!!
+//    reader = OffsetEnvBlockReader(original, pos + modded, pos + target)
+//    val result = func()
+//    reader = original
+//    return result
+//}