Support beta Rust release. Closes #8 (#11)

* Remove seemingly unneeded const on MetadataKey<T> new

* Change biome temperature/moisture to integer, x100 to remove floating-point so can use within stable 'const fn'

* Remove unstable const_fn feature, now using stable const fn: see https://www.reddit.com/r/rust/comments/9msqfn/const_fn_soon_on_stable_rust/

* Test on Rust beta (awaiting 1.31 release for stable)

* Update readme for beta Rust support

.travis.yml

@@ -3,7 +3,7 @@ sudo: required
 dist: trusty
 rust:
   - nightly
-  - nightly-2018-10-24
+  - beta
 matrix:
   allow_failures:
     - rust: nightly

README.md

@@ -20,7 +20,7 @@ Feel free to pop in to say hi, [Webchat can be found here](https://irc.spi.gt/ir
 ## Building
 For more detailed info and platform specific instructions check the [wiki](https://github.com/Thinkofname/steven-rust/wiki/Compiling-and-or-running).
 
-Currently requires SDL2, OpenSSL and **nightly** rust to build.
+Currently requires SDL2, OpenSSL and **beta or nightly** Rust to build.
 
 `cargo build --release`
 

src/main.rs

@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #![recursion_limit="300"]
-#![feature(const_fn)]
 
 extern crate sdl2;
 extern crate zip;

src/types/metadata.rs

@@ -29,7 +29,7 @@ pub struct MetadataKey<T: MetaValue> {
 
 impl <T: MetaValue> MetadataKey<T> {
     #[allow(dead_code)]
-    const fn new(index: i32) -> MetadataKey<T> {
+    fn new(index: i32) -> MetadataKey<T> {
         MetadataKey {
             index: index,
             ty: PhantomData,

src/world/biome.rs

@@ -4,12 +4,12 @@ use image::Rgba;
 #[derive(Clone, Copy)]
 pub struct Biome {
     pub id: usize,
-    pub temperature: f64,
-    pub moisture: f64,
+    pub temperature: i16,
+    pub moisture: i16,
 }
 
 impl Biome {
-    const fn new(id: usize, t: f64, m: f64) -> Biome {
+    const fn new(id: usize, t: i16, m: i16) -> Biome {
         Biome {
             id: id,
             temperature: t,
@@ -22,8 +22,8 @@ impl Biome {
     }
 
     pub fn get_color_index(self) -> usize {
-        let t = self.temperature.min(1.0).max(0.0);
-        let m = self.moisture.min(1.0).max(0.0);
+        let t = (self.temperature as f64 / 100f64) .min(1.0).max(0.0);
+        let m = (self.moisture as f64 / 100f64).min(1.0).max(0.0);
         (((1.0 - t) * 255.0) as usize) | ((((1.0 - (m*t)) * 255.0) as usize) << 8)
     }
 
@@ -64,68 +64,68 @@ macro_rules! define_biomes {
 }
 
 define_biomes! {
-pub const OCEAN: Biome = Biome::new(0, 0.5, 0.5);
-pub const PLAINS: Biome = Biome::new(1, 0.8, 0.4);
-pub const DESERT: Biome = Biome::new(2, 2.0, 0.0);
-pub const EXTREME_HILLS: Biome = Biome::new(3, 0.2, 0.3);
-pub const FOREST: Biome = Biome::new(4, 0.7, 0.8);
-pub const TAIGA: Biome = Biome::new(5, 0.05, 0.8);
-pub const SWAMPLAND: Biome = Biome::new(6, 0.8, 0.9);
-pub const RIVER: Biome = Biome::new(7, 0.5, 0.5);
-pub const HELL: Biome = Biome::new(8, 2.0, 0.0);
-pub const THE_END: Biome = Biome::new(9, 0.5, 0.5);
-pub const FROZEN_OCEAN: Biome = Biome::new(10, 0.0, 0.5);
-pub const FROZEN_RIVER: Biome = Biome::new(11, 0.0, 0.5);
-pub const ICE_PLAINS: Biome = Biome::new(12, 0.0, 0.5);
-pub const ICE_MOUNTAINS: Biome = Biome::new(13, 0.0, 0.5);
-pub const MUSHROOM_ISLAND: Biome = Biome::new(14, 0.9, 1.0);
-pub const MUSHROOM_ISLAND_SHORE: Biome = Biome::new(15, 0.9, 1.0);
-pub const BEACH: Biome = Biome::new(16, 0.8, 0.4);
-pub const DESERT_HILLS: Biome = Biome::new(17, 2.0, 0.0);
-pub const FOREST_HILLS: Biome = Biome::new(18, 0.7, 0.8);
-pub const TAIGA_HILLS: Biome = Biome::new(19, 0.2, 0.7);
-pub const EXTREME_HILLS_EDGE: Biome = Biome::new(20, 0.2, 0.3);
-pub const JUNGLE: Biome = Biome::new(21, 1.2, 0.9);
-pub const JUNGLE_HILLS: Biome = Biome::new(22, 1.2, 0.9);
-pub const JUNGLE_EDGE: Biome = Biome::new(23, 0.95, 0.8);
-pub const DEEP_OCEAN: Biome = Biome::new(24, 0.5, 0.5);
-pub const STONE_BEACH: Biome = Biome::new(25, 0.2, 0.3);
-pub const COLD_BEACH: Biome = Biome::new(26, 0.05, 0.3);
-pub const BIRCH_FOREST: Biome = Biome::new(27, 0.6, 0.6);
-pub const BIRCH_FOREST_HILLS: Biome = Biome::new(28, 0.6, 0.6);
-pub const ROOFED_FOREST: Biome = Biome::new(29, 0.7, 0.8);
-pub const COLD_TAIGA: Biome = Biome::new(30, -0.5, 0.4);
-pub const COLD_TAIGA_HILLS: Biome = Biome::new(31, -0.5, 0.4);
-pub const MEGA_TAIGA: Biome = Biome::new(32, 0.3, 0.8);
-pub const MEGA_TAIGA_HILLS: Biome = Biome::new(33, 0.3, 0.8);
-pub const EXTREME_HILLS_PLUS: Biome = Biome::new(34, 0.2, 0.3);
-pub const SAVANNA: Biome = Biome::new(35, 1.2, 0.0);
-pub const SAVANNA_PLATEAU: Biome = Biome::new(36, 1.0, 0.0);
-pub const MESA: Biome = Biome::new(37, 2.0, 0.0);
-pub const MESA_PLATEAU_FOREST: Biome = Biome::new(38, 2.0, 0.0);
-pub const MESA_PLATEAU: Biome = Biome::new(39, 2.0, 0.0);
+pub const OCEAN: Biome = Biome::new(0, 50, 50);
+pub const PLAINS: Biome = Biome::new(1, 80, 40);
+pub const DESERT: Biome = Biome::new(2, 200, 0);
+pub const EXTREME_HILLS: Biome = Biome::new(3, 20, 30);
+pub const FOREST: Biome = Biome::new(4, 70, 80);
+pub const TAIGA: Biome = Biome::new(5, 5, 80);
+pub const SWAMPLAND: Biome = Biome::new(6, 80, 90);
+pub const RIVER: Biome = Biome::new(7, 50, 50);
+pub const HELL: Biome = Biome::new(8, 200, 0);
+pub const THE_END: Biome = Biome::new(9, 50, 50);
+pub const FROZEN_OCEAN: Biome = Biome::new(10, 0, 50);
+pub const FROZEN_RIVER: Biome = Biome::new(11, 0, 50);
+pub const ICE_PLAINS: Biome = Biome::new(12, 0, 50);
+pub const ICE_MOUNTAINS: Biome = Biome::new(13, 0, 50);
+pub const MUSHROOM_ISLAND: Biome = Biome::new(14, 90, 100);
+pub const MUSHROOM_ISLAND_SHORE: Biome = Biome::new(15, 90, 100);
+pub const BEACH: Biome = Biome::new(16, 80, 40);
+pub const DESERT_HILLS: Biome = Biome::new(17, 200, 0);
+pub const FOREST_HILLS: Biome = Biome::new(18, 70, 80);
+pub const TAIGA_HILLS: Biome = Biome::new(19, 20, 70);
+pub const EXTREME_HILLS_EDGE: Biome = Biome::new(20, 20, 30);
+pub const JUNGLE: Biome = Biome::new(21, 120, 90);
+pub const JUNGLE_HILLS: Biome = Biome::new(22, 120, 90);
+pub const JUNGLE_EDGE: Biome = Biome::new(23, 95, 80);
+pub const DEEP_OCEAN: Biome = Biome::new(24, 50, 50);
+pub const STONE_BEACH: Biome = Biome::new(25, 20, 30);
+pub const COLD_BEACH: Biome = Biome::new(26, 5, 30);
+pub const BIRCH_FOREST: Biome = Biome::new(27, 60, 60);
+pub const BIRCH_FOREST_HILLS: Biome = Biome::new(28, 60, 60);
+pub const ROOFED_FOREST: Biome = Biome::new(29, 70, 80);
+pub const COLD_TAIGA: Biome = Biome::new(30, -50, 40);
+pub const COLD_TAIGA_HILLS: Biome = Biome::new(31, -50, 40);
+pub const MEGA_TAIGA: Biome = Biome::new(32, 30, 80);
+pub const MEGA_TAIGA_HILLS: Biome = Biome::new(33, 30, 80);
+pub const EXTREME_HILLS_PLUS: Biome = Biome::new(34, 20, 30);
+pub const SAVANNA: Biome = Biome::new(35, 120, 0);
+pub const SAVANNA_PLATEAU: Biome = Biome::new(36, 100, 0);
+pub const MESA: Biome = Biome::new(37, 200, 0);
+pub const MESA_PLATEAU_FOREST: Biome = Biome::new(38, 200, 0);
+pub const MESA_PLATEAU: Biome = Biome::new(39, 200, 0);
 
-pub const SUNFLOWER_PLAINS: Biome = Biome::new(129, 0.8, 0.4);
-pub const DESERT_MOUNTAIN: Biome = Biome::new(130, 2.0, 0.0);
-pub const EXTREME_HILLS_MOUNTAINS: Biome = Biome::new(131, 0.2, 0.3);
-pub const FLOWER_FOREST: Biome = Biome::new(132, 0.7, 0.8);
-pub const TAIGA_M: Biome = Biome::new(133, 0.05, 0.8);
-pub const SWAMPLAND_MOUNTAINS: Biome = Biome::new(134, 0.8, 0.9);
-pub const ICE_PLAINS_SPIKES: Biome = Biome::new(140, 0.0, 0.5);
-pub const JUNGLE_MOUNTAINS: Biome = Biome::new(149, 1.2, 0.9);
-pub const JUNGLE_EDGE_MOUNTAINS: Biome = Biome::new(151, 0.95, 0.8);
-pub const BIRCH_FOREST_MOUNTAINS: Biome = Biome::new(155, 0.6, 0.6);
-pub const BIRCH_FOREST_HILLS_MOUNTAINS: Biome = Biome::new(156, 0.6, 0.6);
-pub const ROOFED_FOREST_MOUNTAINS: Biome = Biome::new(157, 0.7, 0.8);
-pub const COLD_TAIGA_MOUNTAINS: Biome = Biome::new(158, -0.5, 0.4);
-pub const MEGA_SPRUCE_TAIGA: Biome = Biome::new(160, 0.25, 0.8);
-pub const MEGA_SPRUCE_TAIGA_HILLS: Biome = Biome::new(161, 0.3, 0.8);
-pub const EXTREME_HILLS_PLUS_MOUNTAINS: Biome = Biome::new(162, 0.2, 0.3);
-pub const SAVANNA_MOUNTAINS: Biome = Biome::new(163, 1.2, 0.0);
-pub const SAVANNA_PLATEAU_MOUNTAINS: Biome = Biome::new(164, 1.0, 0.0);
-pub const MESA_BRYCE: Biome = Biome::new(165, 2.0, 0.0);
-pub const MESA_PLATEAU_FOREST_MOUNTAINS: Biome = Biome::new(166, 2.0, 0.0);
-pub const MESA_PLATEAU_MOUNTAINS: Biome = Biome::new(167, 2.0, 0.0);
+pub const SUNFLOWER_PLAINS: Biome = Biome::new(129, 80, 40);
+pub const DESERT_MOUNTAIN: Biome = Biome::new(130, 200, 0);
+pub const EXTREME_HILLS_MOUNTAINS: Biome = Biome::new(131, 20, 30);
+pub const FLOWER_FOREST: Biome = Biome::new(132, 70, 80);
+pub const TAIGA_M: Biome = Biome::new(133, 5, 80);
+pub const SWAMPLAND_MOUNTAINS: Biome = Biome::new(134, 80, 90);
+pub const ICE_PLAINS_SPIKES: Biome = Biome::new(140, 0, 50);
+pub const JUNGLE_MOUNTAINS: Biome = Biome::new(149, 120, 90);
+pub const JUNGLE_EDGE_MOUNTAINS: Biome = Biome::new(151, 95, 80);
+pub const BIRCH_FOREST_MOUNTAINS: Biome = Biome::new(155, 60, 60);
+pub const BIRCH_FOREST_HILLS_MOUNTAINS: Biome = Biome::new(156, 60, 60);
+pub const ROOFED_FOREST_MOUNTAINS: Biome = Biome::new(157, 70, 80);
+pub const COLD_TAIGA_MOUNTAINS: Biome = Biome::new(158, -50, 40);
+pub const MEGA_SPRUCE_TAIGA: Biome = Biome::new(160, 25, 80);
+pub const MEGA_SPRUCE_TAIGA_HILLS: Biome = Biome::new(161, 30, 80);
+pub const EXTREME_HILLS_PLUS_MOUNTAINS: Biome = Biome::new(162, 20, 30);
+pub const SAVANNA_MOUNTAINS: Biome = Biome::new(163, 120, 0);
+pub const SAVANNA_PLATEAU_MOUNTAINS: Biome = Biome::new(164, 100, 0);
+pub const MESA_BRYCE: Biome = Biome::new(165, 200, 0);
+pub const MESA_PLATEAU_FOREST_MOUNTAINS: Biome = Biome::new(166, 200, 0);
+pub const MESA_PLATEAU_MOUNTAINS: Biome = Biome::new(167, 200, 0);
 
-pub const INVALID: Biome = Biome::new(255, 0.0, 0.0);
+pub const INVALID: Biome = Biome::new(255, 0, 0);
 }