Merge branch 'bd/1455' into 'master'

#1455 | Sprites now only spawn on designated block types

See merge request veloren/veloren!3434

world/src/layer/scatter.rs

@@ -1,5 +1,5 @@
 use crate::{column::ColumnSample, sim::SimChunk, Canvas, CONFIG};
-use common::terrain::{Block, SpriteKind};
+use common::terrain::{Block, BlockKind, SpriteKind};
 use noise::NoiseFn;
 use rand::prelude::*;
 use std::f32;
@@ -21,15 +21,23 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
     use WaterMode::*;
 
     use SpriteKind::*;
+
+    struct ScatterConfig {
+        kind: SpriteKind,
+        water_mode: WaterMode,
+        permit: fn(BlockKind) -> bool,
+        f: fn(&SimChunk, &ColumnSample) -> (f32, Option<(f32, f32, f32)>),
+    }
+
     // TODO: Add back all sprites we had before
-    let scatter: &[(
+    let scatter: &[ScatterConfig] = &[
-        _,
-        WaterMode,
-        fn(&SimChunk, &ColumnSample) -> (f32, Option<(f32, f32, f32)>),
-    )] = &[
         // (density, Option<(base_density_proportion, wavelen, threshold)>)
         // Flowers
-        (BlueFlower, Ground, |_, col| {
+        ScatterConfig {
+            kind: BlueFlower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.7).min(close(
                         col.humidity,
@@ -40,8 +48,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 256.0,
                     Some((0.0, 256.0, 0.25)),
                 )
-        }),
+            },
-        (PinkFlower, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: PinkFlower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.0, 0.7).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -49,8 +62,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 100.0, 0.1)),
                 )
-        }),
+            },
-        (PurpleFlower, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: PurpleFlower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.7).min(close(
                         col.humidity,
@@ -61,8 +79,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 100.0, 0.1)),
                 )
-        }),
+            },
-        (RedFlower, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: RedFlower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.tropical_temp, 0.7).min(close(
                         col.humidity,
@@ -73,8 +96,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 100.0, 0.1)),
                 )
-        }),
+            },
-        (WhiteFlower, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: WhiteFlower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.0, 0.7).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -82,8 +110,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 100.0, 0.1)),
                 )
-        }),
+            },
-        (YellowFlower, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: YellowFlower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.0, 0.7).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -91,8 +124,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 100.0, 0.1)),
                 )
-        }),
+            },
-        (Cotton, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Cotton,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.7).min(close(
                         col.humidity,
@@ -103,8 +141,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 75.0,
                     Some((0.0, 256.0, 0.25)),
                 )
-        }),
+            },
-        (Sunflower, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Sunflower,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.0, 0.7).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -112,8 +155,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 100.0, 0.15)),
                 )
-        }),
+            },
-        (WildFlax, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: WildFlax,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.0, 0.7).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -121,41 +169,66 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 600.0,
                     Some((0.0, 100.0, 0.15)),
                 )
-        }),
+            },
+        },
         // Herbs and Spices
-        (LingonBerry, Ground, |_, col| {
+        ScatterConfig {
+            kind: LingonBerry,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.jungle_hum, 0.5))
                         * MUSH_FACT
                         * 2.5,
                     None,
                 )
-        }),
+            },
-        (LeafyPlant, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: LeafyPlant,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.jungle_hum, 0.3))
                         * GRASS_FACT
                         * 4.0,
                     None,
                 )
-        }),
+            },
-        (JungleLeafyPlant, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: JungleLeafyPlant,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * GRASS_FACT
                         * 32.0,
                     Some((0.15, 64.0, 0.2)),
                 )
-        }),
+            },
-        (Fern, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Fern,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.forest_hum, 0.5))
                         * GRASS_FACT
                         * 0.25,
                     Some((0.0, 64.0, 0.2)),
                 )
-        }),
+            },
-        (JungleFern, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: JungleFern,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -163,8 +236,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 200.0,
                     Some((0.0, 84.0, 0.35)),
                 )
-        }),
+            },
-        (Blueberry, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Blueberry,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.5).min(close(
                         col.humidity,
@@ -174,8 +252,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 0.3,
                     None,
                 )
-        }),
+            },
-        (Pumpkin, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Pumpkin,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.5).min(close(
                         col.humidity,
@@ -185,65 +268,124 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 500.0,
                     Some((0.0, 512.0, 0.05)),
                 )
-        }),
+            },
+        },
         // Collectable Objects
         // Only spawn twigs in temperate forests
-        (Twigs, Ground, |_, col| {
+        ScatterConfig {
+            kind: Twigs,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     (col.tree_density * 1.25 - 0.25).powf(0.5).max(0.0) * 0.75e-3,
                     None,
                 )
-        }),
+            },
+        },
         // Only spawn logs in temperate forests (arbitrarily set to ~20% twig density)
-        (Wood, Ground, |_, col| {
+        ScatterConfig {
+            kind: Wood,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     (col.tree_density * 1.25 - 0.25).powf(0.5).max(0.0) * 0.15e-3,
                     None,
                 )
-        }),
+            },
-        (Stones, Ground, |chunk, _| {
+        },
-            ((chunk.rockiness - 0.5).max(0.025) * 1.0e-3, None)
+        ScatterConfig {
-        }),
+            kind: Stones,
-        (Copper, Ground, |chunk, _| {
+            water_mode: Ground,
-            ((chunk.rockiness - 0.5).max(0.0) * 1.5e-3, None)
+            permit: |b| {
-        }),
+                matches!(
-        (Tin, Ground, |chunk, _| {
+                    b,
-            ((chunk.rockiness - 0.5).max(0.0) * 1.5e-3, None)
+                    BlockKind::Earth | BlockKind::Grass | BlockKind::Rock | BlockKind::Sand
-        }),
+                )
+            },
+            f: |chunk, _| ((chunk.rockiness - 0.5).max(0.025) * 1.0e-3, None),
+        },
+        ScatterConfig {
+            kind: Copper,
+            water_mode: Ground,
+            permit: |b| {
+                matches!(
+                    b,
+                    BlockKind::Earth | BlockKind::Grass | BlockKind::Rock | BlockKind::Sand
+                )
+            },
+            f: |chunk, _| ((chunk.rockiness - 0.5).max(0.0) * 1.5e-3, None),
+        },
+        ScatterConfig {
+            kind: Tin,
+            water_mode: Ground,
+            permit: |b| {
+                matches!(
+                    b,
+                    BlockKind::Earth | BlockKind::Grass | BlockKind::Rock | BlockKind::Sand
+                )
+            },
+            f: |chunk, _| ((chunk.rockiness - 0.5).max(0.0) * 1.5e-3, None),
+        },
         // Don't spawn Mushrooms in snowy regions
-        (Mushroom, Ground, |_, col| {
+        ScatterConfig {
+            kind: Mushroom,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.forest_hum, 0.35))
                         * MUSH_FACT,
                     None,
                 )
-        }),
+            },
+        },
         // Grass
-        (ShortGrass, Ground, |_, col| {
+        ScatterConfig {
+            kind: ShortGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.2, 0.75).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * GRASS_FACT
                         * 150.0,
                     Some((0.3, 64.0, 0.3)),
                 )
-        }),
+            },
-        (MediumGrass, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: MediumGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.2, 0.6).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * GRASS_FACT
                         * 120.0,
                     Some((0.3, 64.0, 0.3)),
                 )
-        }),
+            },
-        (LongGrass, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: LongGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.35).min(close(col.humidity, CONFIG.jungle_hum, 0.3))
                         * GRASS_FACT
                         * 150.0,
                     Some((0.1, 48.0, 0.3)),
                 )
-        }),
+            },
-        (JungleRedGrass, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: JungleRedGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.3, 0.4).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * col.tree_density
@@ -251,7 +393,8 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 350.0,
                     Some((0.0, 128.0, 0.25)),
                 )
-        }),
+            },
+        },
         // Jungle Sprites
         // (LongGrass, Ground, |c, col| {
         //     (
@@ -271,7 +414,11 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                 None,
             )
         }),*/
-        (GrassSnow, Ground, |_, col| {
+        ScatterConfig {
+            kind: GrassSnow,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.snow_temp - 0.2, 0.4).min(close(
                         col.humidity,
@@ -281,8 +428,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * 100.0,
                     Some((0.0, 48.0, 0.2)),
                 )
-        }),
+            },
-        (Moonbell, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Moonbell,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.snow_temp - 0.2, 0.4).min(close(
                         col.humidity,
@@ -291,9 +443,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                     )) * 0.003,
                     Some((0.0, 48.0, 0.2)),
                 )
-        }),
+            },
+        },
         // Savanna Plants
-        (SavannaGrass, Ground, |_, col| {
+        ScatterConfig {
+            kind: SavannaGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     {
                         let savanna = close(col.temp, 1.0, 0.4) * close(col.humidity, 0.2, 0.25);
@@ -302,8 +459,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                     },
                     Some((0.15, 64.0, 0.2)),
                 )
-        }),
+            },
-        (TallSavannaGrass, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: TallSavannaGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     {
                         let savanna = close(col.temp, 1.0, 0.4) * close(col.humidity, 0.2, 0.25);
@@ -312,8 +474,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                     },
                     Some((0.1, 48.0, 0.2)),
                 )
-        }),
+            },
-        (RedSavannaGrass, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: RedSavannaGrass,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     {
                         let savanna = close(col.temp, 1.0, 0.4) * close(col.humidity, 0.2, 0.25);
@@ -322,8 +489,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                     },
                     Some((0.15, 48.0, 0.25)),
                 )
-        }),
+            },
-        (SavannaBush, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: SavannaBush,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     {
                         let savanna = close(col.temp, 1.0, 0.4) * close(col.humidity, 0.2, 0.25);
@@ -332,52 +504,94 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                     },
                     Some((0.1, 96.0, 0.15)),
                 )
-        }),
+            },
+        },
         // Desert Plants
-        (DeadBush, Ground, |_, col| {
+        ScatterConfig {
+            kind: DeadBush,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.95).min(close(col.humidity, 0.0, 0.3)) * MUSH_FACT * 7.5,
                     None,
                 )
-        }),
+            },
-        (Pyrebloom, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Pyrebloom,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
-                close(col.temp, 1.0, 0.95).min(close(col.humidity, 0.0, 0.3)) * MUSH_FACT * 0.35,
+                    close(col.temp, 1.0, 0.95).min(close(col.humidity, 0.0, 0.3))
+                        * MUSH_FACT
+                        * 0.35,
                     None,
                 )
-        }),
+            },
-        (LargeCactus, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: LargeCactus,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.25).min(close(col.humidity, 0.0, 0.1)) * MUSH_FACT * 1.5,
                     None,
                 )
-        }),
+            },
-        (RoundCactus, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: RoundCactus,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.25).min(close(col.humidity, 0.0, 0.1)) * MUSH_FACT * 2.5,
                     None,
                 )
-        }),
+            },
-        (ShortCactus, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: ShortCactus,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.25).min(close(col.humidity, 0.0, 0.1)) * MUSH_FACT * 2.5,
                     None,
                 )
-        }),
+            },
-        (MedFlatCactus, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: MedFlatCactus,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.25).min(close(col.humidity, 0.0, 0.1)) * MUSH_FACT * 2.5,
                     None,
                 )
-        }),
+            },
-        (ShortFlatCactus, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: ShortFlatCactus,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.25).min(close(col.humidity, 0.0, 0.1)) * MUSH_FACT * 2.5,
                     None,
                 )
-        }),
+            },
+        },
         // Underwater chests
-        (ChestBuried, Underwater, |_, col| {
+        ScatterConfig {
+            kind: ChestBuried,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth | BlockKind::Sand),
+            f: |_, col| {
                 (
                     MUSH_FACT
                         * 1.0e-6
@@ -388,9 +602,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     None,
                 )
-        }),
+            },
+        },
         // Underwater mud piles
-        (Mud, Underwater, |_, col| {
+        ScatterConfig {
+            kind: Mud,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     MUSH_FACT
                         * 1.0e-3
@@ -401,9 +620,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     None,
                 )
-        }),
+            },
+        },
         // Underwater grass
-        (GrassBlue, Underwater, |_, col| {
+        ScatterConfig {
+            kind: GrassBlue,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     MUSH_FACT
                         * 250.0
@@ -414,9 +638,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 100.0, 0.15)),
                 )
-        }),
+            },
+        },
         // seagrass
-        (Seagrass, Underwater, |_, col| {
+        ScatterConfig {
+            kind: Seagrass,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.8)
                         * MUSH_FACT
@@ -430,22 +659,34 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 150.0, 0.3)),
                 )
-        }),
+            },
+        },
         // seagrass, coastal patches
-        (Seagrass, Underwater, |_, col| {
+        ScatterConfig {
+            kind: Seagrass,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     MUSH_FACT
                         * 600.0
-                    * if col.water_level <= CONFIG.sea_level && (col.water_level - col.alt) < 3.0 {
+                        * if col.water_level <= CONFIG.sea_level
+                            && (col.water_level - col.alt) < 3.0
+                        {
                             1.0
                         } else {
                             0.0
                         },
                     Some((0.0, 150.0, 0.4)),
                 )
-        }),
+            },
+        },
         // scattered seaweed (temperate species)
-        (SeaweedTemperate, Underwater, |_, col| {
+        ScatterConfig {
+            kind: SeaweedTemperate,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.8)
                         * MUSH_FACT
@@ -459,9 +700,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 500.0, 0.75)),
                 )
-        }),
+            },
+        },
         // scattered seaweed (tropical species)
-        (SeaweedTropical, Underwater, |_, col| {
+        ScatterConfig {
+            kind: SeaweedTropical,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.95)
                         * MUSH_FACT
@@ -475,9 +721,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 500.0, 0.75)),
                 )
-        }),
+            },
+        },
         // Caulerpa lentillifera algae patch
-        (SeaGrapes, Underwater, |_, col| {
+        ScatterConfig {
+            kind: SeaGrapes,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     MUSH_FACT
                         * 250.0
@@ -490,9 +741,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 100.0, 0.15)),
                 )
-        }),
+            },
+        },
         // Caulerpa prolifera algae patch
-        (WavyAlgae, Underwater, |_, col| {
+        ScatterConfig {
+            kind: WavyAlgae,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     MUSH_FACT
                         * 250.0
@@ -505,9 +761,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 100.0, 0.15)),
                 )
-        }),
+            },
+        },
         // Mermaids' fan algae patch
-        (MermaidsFan, Underwater, |_, col| {
+        ScatterConfig {
+            kind: MermaidsFan,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.95)
                         * MUSH_FACT
@@ -521,9 +782,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 50.0, 0.10)),
                 )
-        }),
+            },
+        },
         // Sea anemones
-        (SeaAnemone, Underwater, |_, col| {
+        ScatterConfig {
+            kind: SeaAnemone,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.8)
                         * MUSH_FACT
@@ -537,9 +803,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 100.0, 0.3)),
                 )
-        }),
+            },
+        },
         // Giant Kelp
-        (GiantKelp, Underwater, |_, col| {
+        ScatterConfig {
+            kind: GiantKelp,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.8)
                         * MUSH_FACT
@@ -553,9 +824,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 200.0, 0.4)),
                 )
-        }),
+            },
+        },
         // Bull Kelp
-        (BullKelp, Underwater, |_, col| {
+        ScatterConfig {
+            kind: BullKelp,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     close(col.temp, CONFIG.temperate_temp, 0.7)
                         * MUSH_FACT
@@ -569,9 +845,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 75.0, 0.3)),
                 )
-        }),
+            },
+        },
         // Stony Corals
-        (StonyCoral, Underwater, |_, col| {
+        ScatterConfig {
+            kind: StonyCoral,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.9)
                         * MUSH_FACT
@@ -585,9 +866,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 120.0, 0.4)),
                 )
-        }),
+            },
+        },
         // Soft Corals
-        (SoftCoral, Underwater, |_, col| {
+        ScatterConfig {
+            kind: SoftCoral,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |_, col| {
                 (
                     close(col.temp, 1.0, 0.9)
                         * MUSH_FACT
@@ -601,9 +887,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     Some((0.0, 120.0, 0.4)),
                 )
-        }),
+            },
+        },
         // Seashells
-        (Seashells, Underwater, |c, col| {
+        ScatterConfig {
+            kind: Seashells,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |c, col| {
                 (
                     (c.rockiness - 0.5).max(0.0)
                         * 1.0e-3
@@ -616,8 +907,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     None,
                 )
-        }),
+            },
-        (Stones, Underwater, |c, col| {
+        },
+        ScatterConfig {
+            kind: Stones,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Earth),
+            f: |c, col| {
                 (
                     (c.rockiness - 0.5).max(0.0)
                         * 1.0e-3
@@ -628,9 +924,14 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         },
                     None,
                 )
-        }),
+            },
+        },
         //River-related scatter
-        (LillyPads, Floating, |_, col| {
+        ScatterConfig {
+            kind: LillyPads,
+            water_mode: Floating,
+            permit: |_| true,
+            f: |_, col| {
                 (
                     close(col.temp, 0.2, 0.6).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * GRASS_FACT
@@ -641,8 +942,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                             .map_or(0.0, |d| 1.0 / (1.0 + (d.abs() * 0.4).powi(2))),
                     Some((0.0, 128.0, 0.35)),
                 )
-        }),
+            },
-        (Reed, Underwater, |_, col| {
+        },
+        ScatterConfig {
+            kind: Reed,
+            water_mode: Underwater,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.temp, 0.2, 0.6).min(close(col.humidity, CONFIG.jungle_hum, 0.4))
                         * GRASS_FACT
@@ -653,8 +959,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                             .map_or(0.0, |d| 1.0 / (1.0 + (d.abs() * 0.40).powi(2))),
                     Some((0.2, 128.0, 0.5)),
                 )
-        }),
+            },
-        (Reed, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Reed,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     close(col.humidity, CONFIG.jungle_hum, 0.9)
                         * col
@@ -664,8 +975,13 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * ((col.alt - CONFIG.sea_level) / 12.0).clamped(0.0, 1.0),
                     Some((0.2, 128.0, 0.5)),
                 )
-        }),
+            },
-        (Bamboo, Ground, |_, col| {
+        },
+        ScatterConfig {
+            kind: Bamboo,
+            water_mode: Ground,
+            permit: |b| matches!(b, BlockKind::Grass),
+            f: |_, col| {
                 (
                     0.014
                         * close(col.humidity, CONFIG.jungle_hum, 0.9)
@@ -676,16 +992,29 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                         * ((col.alt - CONFIG.sea_level) / 12.0).clamped(0.0, 1.0),
                     Some((0.2, 128.0, 0.5)),
                 )
-        }),
+            },
+        },
     ];
 
     canvas.foreach_col(|canvas, wpos2d, col| {
         let underwater = col.water_level.floor() > col.alt;
 
-        let kind = scatter
+        let kind = scatter.iter().enumerate().find_map(
-            .iter()
+            |(
-            .enumerate()
+                i,
-            .find_map(|(i, (kind, water_mode, f))| {
+                ScatterConfig {
+                    kind,
+                    water_mode,
+                    permit,
+                    f,
+                },
+            )| {
+                let block_kind = canvas
+                    .get(Vec3::new(wpos2d.x, wpos2d.y, col.alt as i32))
+                    .kind();
+                if !permit(block_kind) {
+                    return None;
+                }
                 let (density, patch) = f(canvas.chunk(), col);
                 let density = patch
                     .map(|(base_density_prop, wavelen, threshold)| {
@@ -715,7 +1044,8 @@ pub fn apply_scatter_to(canvas: &mut Canvas, rng: &mut impl Rng) {
                 } else {
                     None
                 }
-            });
+            },
+        );
 
         if let Some((kind, water_mode)) = kind {
             let (alt, is_under): (_, fn(Block) -> bool) = match water_mode {