resource: do not require Biome to get color for all block types

Only grass, foliage and water have biome-dependent colors.

src/bin/minedmap/tile_renderer.rs

@@ -8,7 +8,7 @@ use num_integer::div_mod_floor;
 
 use minedmap::{
 	io::{fs, storage},
-	resource::{block_color, Biome},
+	resource::{block_color, needs_biome, Biome},
 	types::*,
 };
 
@@ -85,8 +85,14 @@ impl<'a> TileRenderer<'a> {
 	) -> Option<[u8; 4]> {
 		let block = chunk.blocks[block_coords]?;
 		let depth = chunk.depths[block_coords]?;
+
+		if !needs_biome(block) {
+			return Some(block_color(block, None, depth.0 as f32));
+		}
+
 		let biome = chunk.biomes[block_coords].as_ref()?;
-		Some(block_color(block, biome, depth.0 as f32))
+
+		Some(block_color(block, Some(biome), depth.0 as f32))
 	}
 
 	fn render_chunk(

src/resource/block_color.rs

@@ -72,16 +72,24 @@ impl BiomeExt for Biome {
 const BIRCH_COLOR: Vec3 = Vec3::new(0.502, 0.655, 0.333); // == color_vec(Color([128, 167, 85]))
 const EVERGREEN_COLOR: Vec3 = Vec3::new(0.380, 0.600, 0.380); // == color_vec(Color([97, 153, 97]))
 
-pub fn block_color(block: BlockType, biome: &Biome, depth: f32) -> [u8; 4] {
+pub fn needs_biome(block: BlockType) -> bool {
 	use super::BlockFlag::*;
 
+	block.is(Grass) || block.is(Foliage) || block.is(Water)
+}
+
+pub fn block_color(block: BlockType, biome: Option<&Biome>, depth: f32) -> [u8; 4] {
+	use super::BlockFlag::*;
+
+	let get_biome = || biome.expect("needs biome to determine block color");
+
 	let mut color = color_vec_unscaled(block.color);
 
 	if block.is(Grass) {
-		color *= biome.grass_color(depth);
+		color *= get_biome().grass_color(depth);
 	}
 	if block.is(Foliage) {
-		color *= biome.foliage_color(depth);
+		color *= get_biome().foliage_color(depth);
 	}
 	if block.is(Birch) {
 		color *= BIRCH_COLOR;
@@ -90,7 +98,7 @@ pub fn block_color(block: BlockType, biome: &Biome, depth: f32) -> [u8; 4] {
 		color *= EVERGREEN_COLOR;
 	}
 	if block.is(Water) {
-		color *= biome.water_color();
+		color *= get_biome().water_color();
 	}
 
 	color *= 0.5 + 0.005 * depth;

src/resource/mod.rs

@@ -91,7 +91,7 @@ impl BlockTypes {
 }
 
 pub use biomes::{Biome, BiomeGrassColorModifier};
-pub use block_color::block_color;
+pub use block_color::{block_color, needs_biome};
 
 #[derive(Debug)]
 pub struct BiomeTypes {