From f8c8ca78bad8e0c66b1429666442c958be1a33bf Mon Sep 17 00:00:00 2001
From: Matthias Schiffer <mschiffer@universe-factory.net>
Date: Fri, 28 Feb 2025 12:12:58 +0100
Subject: [PATCH] Switch from zlib-ng to zlib-rs

zlib-rs provides the same performance as zlib-ng with minedmap, while
reducing the amount of C code and avoiding the external build dependency
on CMake.
---
 CHANGELOG.md          |  4 ++++
 Cargo.lock            | 27 ++++++++++++---------------
 Cargo.toml            |  4 ++--
 Dockerfile            |  2 +-
 README.md             |  5 -----
 crates/nbt/Cargo.toml |  6 ++----
 6 files changed, 21 insertions(+), 27 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e8fd052..1b84b15 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -45,6 +45,10 @@
 - Unknown biome types (from not yet supported or modded versions of Minecraft)
   will now use plains biome colors as a fallback instead of resulting in water,
   grass and foliage blocks to be rendered as transparent pixels
+- Switched from zlib-ng to zlib-rs
+
+  This should have no noticable effect on the usage of MinedMap, but avoids
+  an external build dependency on CMake.
 
 ## [2.4.0] - 2025-01-11
 
diff --git a/Cargo.lock b/Cargo.lock
index c8cbbe6..7bd83ee 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -212,15 +212,6 @@ version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f46ad14479a25103f283c0f10005961cf086d8dc42205bb44c46ac563475dca6"
 
-[[package]]
-name = "cmake"
-version = "0.1.54"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e7caa3f9de89ddbe2c607f4101924c5abec803763ae9534e4f4d7d8f84aa81f0"
-dependencies = [
- "cc",
-]
-
 [[package]]
 name = "colorchoice"
 version = "1.0.3"
@@ -364,7 +355,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "11faaf5a5236997af9848be0bef4db95824b1d534ebc64d0f0c6cf3e67bd38dc"
 dependencies = [
  "crc32fast",
- "libz-ng-sys",
+ "libz-rs-sys",
  "miniz_oxide",
 ]
 
@@ -609,13 +600,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "libz-ng-sys"
-version = "1.1.21"
+name = "libz-rs-sys"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7cee1488e961a80d172564fd6fcda11d8a4ac6672c06fe008e9213fa60520c2b"
+checksum = "902bc563b5d65ad9bba616b490842ef0651066a1a1dc3ce1087113ffcb873c8d"
 dependencies = [
- "cmake",
- "libc",
+ "zlib-rs",
 ]
 
 [[package]]
@@ -664,6 +654,7 @@ dependencies = [
  "clap",
  "enum-map",
  "fastnbt",
+ "flate2",
  "futures-util",
  "git-version",
  "humantime",
@@ -1426,6 +1417,12 @@ version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
 
+[[package]]
+name = "zlib-rs"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b20717f0917c908dc63de2e44e97f1e6b126ca58d0e391cee86d504eb8fbd05"
+
 [[package]]
 name = "zstd"
 version = "0.13.3"
diff --git a/Cargo.toml b/Cargo.toml
index d213a56..812ad33 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -42,6 +42,7 @@ bincode = "1.3.3"
 clap = { version = "4.1.4", features = ["derive", "wrap_help"] }
 enum-map = "2.7.3"
 fastnbt = "2.3.2"
+flate2 = { version = "1.1.0", features = ["zlib-rs"] }
 futures-util = "0.3.28"
 git-version = "0.3.5"
 humantime = "2.1.0"
@@ -67,7 +68,6 @@ tracing-subscriber = "0.3.17"
 zstd = "0.13.0"
 
 [features]
-default = ["jemalloc-auto", "zlib-ng"]
+default = ["jemalloc-auto"]
 jemalloc-auto = ["dep:minedmap-default-alloc"]
 jemalloc = ["jemalloc-auto", "minedmap-default-alloc/jemalloc"]
-zlib-ng = ["minedmap-nbt/zlib-ng"]
diff --git a/Dockerfile b/Dockerfile
index 389fb08..818971d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,7 +1,7 @@
 FROM docker.io/library/alpine:latest AS builder
 
 WORKDIR /build
-RUN apk add --no-cache build-base cmake cargo
+RUN apk add --no-cache build-base cargo
 
 ARG MINEDMAP_VERSION
 
diff --git a/README.md b/README.md
index 7d60f78..952163f 100644
--- a/README.md
+++ b/README.md
@@ -117,11 +117,6 @@ or newer). The following command can be used to build the current development ve
 cargo install --git 'https://github.com/neocturne/MinedMap.git'
 ```
 
-In addition, CMake is needed to build the zlib-ng library. If you do not have
-CMake installed, you can disable the zlib-ng feature by passing `--no-default-features`
-to cargo. A pure-Rust zlib implementation will be used, which is more portable,
-but slower than zlib-ng.
-
 If you are looking for the older C++ implementation of the MinedMap tile renderer,
 see the [v1.19.1](https://github.com/neocturne/MinedMap/tree/v1.19.1) tag.
 
diff --git a/crates/nbt/Cargo.toml b/crates/nbt/Cargo.toml
index 9f815da..01bbd78 100644
--- a/crates/nbt/Cargo.toml
+++ b/crates/nbt/Cargo.toml
@@ -11,12 +11,10 @@ repository.workspace = true
 anyhow = "1.0.75"
 bytemuck = "1.13.1"
 fastnbt = "2.4.4"
-flate2 = "1.0.27"
+flate2 = "1.1.0"
 minedmap-types = { version = "0.1.4", path = "../types" }
 serde = "1.0.183"
 
-[features]
-zlib-ng = ["flate2/zlib-ng"]
-
 [dev-dependencies]
 clap = { version = "4.3.23", features = ["derive"] }
+flate2 = { version = "1.1.0", features = ["zlib-rs"] }