Added grasses and flowers

- Added CROSimple to optimize simple non-Surface textures
- Added TileRenderCross
- Added Low, Medium and Tall grass
- Added Blue, Purple and White flat flowers
- Added Bushes
- Added tiny Dandelions and tiny Lavanders
- Improved grass and log textures

src/main/java/ru/windcorp/progressia/client/world/cro/ChunkRenderOptimizerSimple.java

@@ -0,0 +1,99 @@
+/*
+ * Progressia
+ * Copyright (C)  2020-2021  Wind Corporation and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package ru.windcorp.progressia.client.world.cro;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.function.Consumer;
+
+import glm.vec._3.i.Vec3i;
+import ru.windcorp.progressia.client.graphics.backend.Usage;
+import ru.windcorp.progressia.client.graphics.model.Renderable;
+import ru.windcorp.progressia.client.graphics.model.Shape;
+import ru.windcorp.progressia.client.graphics.model.ShapePart;
+import ru.windcorp.progressia.client.graphics.world.WorldRenderProgram;
+import ru.windcorp.progressia.client.world.block.BlockRender;
+import ru.windcorp.progressia.client.world.tile.TileRender;
+import ru.windcorp.progressia.common.world.DefaultChunkData;
+import ru.windcorp.progressia.common.world.rels.RelFace;
+
+public class ChunkRenderOptimizerSimple extends ChunkRenderOptimizer {
+
+	public interface BlockOptimizedSimple {
+
+		void getShapeParts(
+			DefaultChunkData chunk,
+			Vec3i relBlockInChunk,
+			Consumer<ShapePart> output
+		);
+
+	}
+
+	public interface TileOptimizedCustom {
+
+		void getShapeParts(
+			DefaultChunkData chunk,
+			Vec3i relBlockInChunk,
+			RelFace blockFace,
+			Consumer<ShapePart> output
+		);
+
+	}
+
+	private final Collection<ShapePart> parts = new ArrayList<>();
+	private final Consumer<ShapePart> partAdder = parts::add;
+
+	public ChunkRenderOptimizerSimple(String id) {
+		super(id);
+	}
+
+	@Override
+	public void startRender() {
+		parts.clear();
+	}
+
+	@Override
+	public void addBlock(BlockRender block, Vec3i relBlockInChunk) {
+		if (block instanceof BlockOptimizedSimple) {
+			((BlockOptimizedSimple) block).getShapeParts(chunk.getData(), relBlockInChunk, partAdder);
+		}
+	}
+
+	@Override
+	public void addTile(TileRender tile, Vec3i relBlockInChunk, RelFace blockFace) {
+		if (tile instanceof TileOptimizedCustom) {
+			((TileOptimizedCustom) tile).getShapeParts(chunk.getData(), relBlockInChunk, blockFace, partAdder);
+		}
+	}
+
+	@Override
+	public Renderable endRender() {
+
+		if (parts.isEmpty()) {
+			return null;
+		}
+		
+		return new Shape(
+			Usage.STATIC,
+			WorldRenderProgram.getDefault(),
+			parts.toArray(new ShapePart[parts.size()])
+		);
+		
+	}
+
+}

src/main/java/ru/windcorp/progressia/client/world/tile/TileRenderCross.java

@@ -0,0 +1,170 @@
+/*
+ * Progressia
+ * Copyright (C)  2020-2021  Wind Corporation and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package ru.windcorp.progressia.client.world.tile;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.function.Consumer;
+
+import glm.mat._3.Mat3;
+import glm.mat._4.Mat4;
+import glm.vec._3.Vec3;
+import glm.vec._3.i.Vec3i;
+import glm.vec._4.Vec4;
+import ru.windcorp.progressia.client.graphics.Colors;
+import ru.windcorp.progressia.client.graphics.backend.Usage;
+import ru.windcorp.progressia.client.graphics.model.Renderable;
+import ru.windcorp.progressia.client.graphics.model.Shape;
+import ru.windcorp.progressia.client.graphics.model.ShapePart;
+import ru.windcorp.progressia.client.graphics.model.ShapeParts;
+import ru.windcorp.progressia.client.graphics.texture.Texture;
+import ru.windcorp.progressia.client.graphics.world.WorldRenderProgram;
+import ru.windcorp.progressia.client.world.cro.ChunkRenderOptimizerSimple.TileOptimizedCustom;
+import ru.windcorp.progressia.common.util.Matrices;
+import ru.windcorp.progressia.common.util.VectorUtil;
+import ru.windcorp.progressia.common.util.Vectors;
+import ru.windcorp.progressia.common.world.DefaultChunkData;
+import ru.windcorp.progressia.common.world.rels.AbsFace;
+import ru.windcorp.progressia.common.world.rels.AxisRotations;
+import ru.windcorp.progressia.common.world.rels.RelFace;
+
+public class TileRenderCross extends TileRender implements TileOptimizedCustom {
+
+	private static final float SQRT_2_OVER_2 = (float) Math.sqrt(2) / 2;
+	private static final float[] ONE_AND_NEGATIVE_ONE = new float[] { 1, -1 };
+
+	private final Texture texture;
+	private final float width;
+
+	public TileRenderCross(String id, Texture texture, boolean allowStretching) {
+		super(id);
+		this.texture = texture;
+		this.width = allowStretching ? 1 : SQRT_2_OVER_2;
+	}
+
+	public Texture getTexture(RelFace blockFace) {
+		return texture;
+	}
+
+	public Vec4 getColorMultiplier(RelFace blockFace) {
+		return Colors.WHITE;
+	}
+
+	@Override
+	public void getShapeParts(
+		DefaultChunkData chunk,
+		Vec3i bic,
+		RelFace blockFace,
+		Consumer<ShapePart> output
+	) {
+		Mat4 transform = Matrices.grab4();
+		Vec3 origin = Vectors.grab3();
+		Vec3 width = Vectors.grab3();
+		Vec3 height = Vectors.grab3();
+
+		Mat3 resolutionMatrix = AxisRotations.getResolutionMatrix3(blockFace.resolve(AbsFace.POS_Z));
+
+		Vec4 color = getColorMultiplier(blockFace);
+		Texture texture = getTexture(blockFace);
+		float originOffset = (1 - this.width) / 2;
+
+		WorldRenderProgram program = WorldRenderProgram.getDefault();
+
+		for (int i = 0; getTransform(chunk, bic, blockFace, i, transform); i++) {
+
+			for (float flip : ONE_AND_NEGATIVE_ONE) {
+				origin.set(flip * (originOffset - 0.5f), originOffset - 0.5f, 0);
+				width.set(flip * this.width, this.width, 0);
+				height.set(0, 0, 1);
+
+				VectorUtil.applyMat4(origin, transform);
+				VectorUtil.rotateOnly(width, transform);
+				VectorUtil.rotateOnly(height, transform);
+
+				origin.z += 1 - 0.5f;
+
+				if (blockFace != RelFace.UP) {
+					resolutionMatrix.mul(origin);
+					resolutionMatrix.mul(width);
+					resolutionMatrix.mul(height);
+				}
+
+				origin.add(bic.x, bic.y, bic.z);
+
+				output.accept(
+					ShapeParts.createRectangle(
+						program,
+						texture,
+						color,
+						origin,
+						width,
+						height,
+						false
+					)
+				);
+				output.accept(
+					ShapeParts.createRectangle(
+						program,
+						texture,
+						color,
+						origin,
+						width,
+						height,
+						true
+					)
+				);
+			}
+
+		}
+
+		Matrices.release(transform);
+		Vectors.release(origin);
+		Vectors.release(width);
+		Vectors.release(height);
+	}
+
+	protected boolean getTransform(
+		DefaultChunkData chunk,
+		Vec3i relBlockInChunk,
+		RelFace blockFace,
+		int count,
+		Mat4 output
+	) {
+		output.identity();
+		return count == 0;
+	}
+
+	@Override
+	public Renderable createRenderable(DefaultChunkData chunk, Vec3i blockInChunk, RelFace blockFace) {
+		Collection<ShapePart> parts = new ArrayList<>(4);
+
+		getShapeParts(chunk, blockInChunk, blockFace, parts::add);
+
+		return new Shape(
+			Usage.STATIC,
+			WorldRenderProgram.getDefault(),
+			parts.toArray(new ShapePart[parts.size()])
+		);
+	}
+
+	@Override
+	public boolean needsOwnRenderable() {
+		return false;
+	}
+
+}

src/main/java/ru/windcorp/progressia/common/util/VectorUtil.java

@@ -180,6 +180,25 @@ public class VectorUtil {
 		return applyMat4(inOut, mat, inOut);
 	}
 	
+	public static Vec3 rotateOnly(Vec3 in, Mat4 mat, Vec3 out) {
+		if (out == null) {
+			out = new Vec3();
+		}
+		
+		Mat3 mat3 = Matrices.grab3();
+		mat3.set(mat);
+
+		mat3.mul(in, out);
+
+		Matrices.release(mat3);
+		
+		return out;
+	}
+	
+	public static Vec3 rotateOnly(Vec3 inOut, Mat4 mat) {
+		return rotateOnly(inOut, mat, inOut);
+	}
+	
 	public static Vec3 rotate(Vec3 in, Vec3 axis, float angle, Vec3 out) {
 		if (out == null) {
 			out = new Vec3();

src/main/java/ru/windcorp/progressia/server/world/context/impl/DefaultServerContextImpl.java

@@ -405,7 +405,7 @@ class DefaultServerContextImpl extends DefaultServerContext
 
 	@Override
 	public int getTileCount(Vec3i location, RelFace face) {
-		assert requireContextRole(Role.TILE_STACK);
+		assert requireContextRole(Role.WORLD);
 		TileDataStack stack = world.getTilesOrNull(location, face.resolve(AbsFace.POS_Z));
 		if (stack == null)
 			return 0;

src/main/java/ru/windcorp/progressia/server/world/generation/surface/context/SurfaceContextImpl.java

@@ -20,7 +20,9 @@ package ru.windcorp.progressia.server.world.generation.surface.context;
 import java.util.Random;
 
 import glm.vec._3.i.Vec3i;
+import ru.windcorp.progressia.common.world.generic.TileGenericStackRO;
 import ru.windcorp.progressia.common.world.rels.RelFace;
+import ru.windcorp.progressia.common.world.tile.TileData;
 import ru.windcorp.progressia.server.world.context.ServerTileContext;
 import ru.windcorp.progressia.server.world.context.impl.RotatingServerContext;
 import ru.windcorp.progressia.server.world.generation.surface.Surface;
@@ -111,4 +113,11 @@ public class SurfaceContextImpl extends RotatingServerContext implements Surface
 		return this;
 	}
 	
+	@Override
+	public void addTile(Vec3i userLocation, RelFace userFace, TileData tile) {
+		if (getTileCount(userLocation, userFace) < TileGenericStackRO.TILES_PER_FACE) {
+			super.addTile(userLocation, userFace, tile);
+		}
+	}
+
 }

src/main/java/ru/windcorp/progressia/test/Rocks.java

@@ -83,6 +83,10 @@ public class Rocks {
 			return blocks.get(variant);
 		}
 		
+		public Collection<BlockData> getBlocks() {
+			return blocks.values();
+		}
+
 		private void register() {
 			for (RockVariant variant : RockVariant.values()) {
 

src/main/java/ru/windcorp/progressia/test/TestContent.java

@@ -38,6 +38,7 @@ import ru.windcorp.progressia.client.graphics.input.KeyMatcher;
 import ru.windcorp.progressia.client.graphics.world.Selection;
 import ru.windcorp.progressia.client.world.block.*;
 import ru.windcorp.progressia.client.world.cro.ChunkRenderOptimizerRegistry;
+import ru.windcorp.progressia.client.world.cro.ChunkRenderOptimizerSimple;
 import ru.windcorp.progressia.client.world.cro.ChunkRenderOptimizerSurface;
 import ru.windcorp.progressia.client.world.entity.*;
 import ru.windcorp.progressia.client.world.tile.*;
@@ -174,9 +175,20 @@ public class TestContent {
 		register(new TileRenderTransparentSurface("Test:Stones", getTileTexture("Stones")));
 		register(new HangingTileLogic("Test:Stones"));
 
-		register(new TileData("Test:YellowFlowers"));
-		register(new TileRenderTransparentSurface("Test:YellowFlowers", getTileTexture("YellowFlowers")));
-		register(new HangingTileLogic("Test:YellowFlowers"));
+		for (String color : new String[] {
+			"Yellow",
+			"White",
+			"Purple",
+			"Blue"
+		}) {
+			
+			String fullName = color + "Flowers";
+			String id = "Test:" + fullName;
+			
+			register(new TileData(id));
+			register(new TileRenderTransparentSurface(id, getTileTexture(fullName)));
+			register(new HangingTileLogic(id));
+		}
 
 		register(new TileData("Test:Sand"));
 		register(new TileRenderTransparentSurface("Test:Sand", getTileTexture("Sand")));
@@ -242,6 +254,32 @@ public class TestContent {
 		register(new TileRenderOpaqueSurface("Test:TilesSmall", getTileTexture("TilesSmall")));
 		register(new HangingTileLogic("Test:TilesSmall"));
 		
+		for (String variant : new String[] {
+			"Low", "Medium", "Tall"
+		}) {
+			String fullName = variant + "Grass";
+			String id = "Test:" + fullName;
+			
+			register(new TileData(id));
+			register(new TileRenderHerb(id, getTileTexture(fullName), 6));
+			register(new HangingTileLogic(id));
+		}
+		
+		for (String variant : new String[] {
+			"Dandelion", "Lavander"
+		}) {
+			String fullName = "Tiny" + variant + "Flowers";
+			String id = "Test:" + fullName;
+			
+			register(new TileData(id));
+			register(new TileRenderTinyFlower(id, getTileTexture(fullName), 8, 0.5f));
+			register(new HangingTileLogic(id));
+		}
+		
+		register(new TileData("Test:Bush"));
+		register(new TileRenderHerb("Test:Bush", getTileTexture("Bush"), 1));
+		register(new HangingTileLogic("Test:Bush"));
+
 		TileDataRegistry.getInstance().values().forEach(PLACEABLE_TILES::add);
 		PLACEABLE_TILES.removeIf(b -> placeableBlacklist.contains(b.getId()));
 		PLACEABLE_TILES.sort(Comparator.comparing(TileData::getId));
@@ -285,6 +323,7 @@ public class TestContent {
 				i -> isAnythingSelected() && TestPlayerControls.getInstance().isBlockSelected()
 			)
 		);
+		
 		logic.register(ControlLogic.of("Test:PlaceBlock", TestContent::onBlockPlaceReceived));
 
 		data.register("Test:PlaceTile", ControlPlaceTileData::new);
@@ -442,7 +481,10 @@ public class TestContent {
 
 	private static void registerMisc() {
 		ChunkIO.registerCodec(new TestChunkCodec());
+		
 		ChunkRenderOptimizerRegistry.getInstance().register("Core:SurfaceOptimizer", ChunkRenderOptimizerSurface::new);
+		ChunkRenderOptimizerRegistry.getInstance().register("Core:SimpleOptimizer", ChunkRenderOptimizerSimple::new);
+		
 		GravityModelRegistry.getInstance().register("Test:TheGravityModel", TestGravityModel::new);
 		GravityModelRegistry.getInstance().register("Test:PlanetGravityModel", PlanetGravityModel::new);
 	}

src/main/java/ru/windcorp/progressia/test/TileRenderHerb.java

@@ -0,0 +1,89 @@
+/*
+ * Progressia
+ * Copyright (C)  2020-2021  Wind Corporation and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package ru.windcorp.progressia.test;
+
+import glm.mat._4.Mat4;
+import glm.vec._3.i.Vec3i;
+import ru.windcorp.progressia.client.graphics.texture.Texture;
+import ru.windcorp.progressia.client.world.tile.TileRenderCross;
+import ru.windcorp.progressia.common.world.DefaultChunkData;
+import ru.windcorp.progressia.common.world.rels.RelFace;
+
+public class TileRenderHerb extends TileRenderCross {
+	
+	/*
+	 * Stolen from OpenJDK's Random implementation
+	 * *evil cackling*
+	 */
+	private static final long MULTIPLIER = 0x5DEECE66DL;
+	private static final long ADDEND = 0xBL;
+	private static final long MASK = (1L << 48) - 1;
+	private static final double DOUBLE_UNIT = 0x1.0p-53; // 1.0 / (1L << 53)
+
+	private static long permute(long seed) {
+		return (seed * MULTIPLIER + ADDEND) & MASK;
+	}
+
+	private static double getDouble(long seed) {
+		final int mask26bits = (1 << 26) - 1;
+		final int mask27bits = (1 << 27) - 1;
+
+		int randomBitsX26 = (int) (seed & 0xFFFFFFFF);
+		int randomBitsX27 = (int) ((seed >>> Integer.SIZE) & 0xFFFFFFFF);
+
+		randomBitsX26 = randomBitsX26 & mask26bits;
+		randomBitsX27 = randomBitsX27 & mask27bits;
+
+		return (((long) (randomBitsX26) << 27) + randomBitsX27) * DOUBLE_UNIT;
+	}
+	
+	private final int maxCount;
+
+	public TileRenderHerb(String id, Texture texture, int maxCount) {
+		super(id, texture, true);
+		this.maxCount = maxCount;
+	}
+	
+	@Override
+	protected boolean getTransform(
+		DefaultChunkData chunk,
+		Vec3i relBlockInChunk,
+		RelFace blockFace,
+		int count,
+		Mat4 output
+	) {
+		
+		long seed = permute(count ^ getId().hashCode());
+		seed = permute(seed + relBlockInChunk.x);
+		seed = permute(seed + relBlockInChunk.y);
+		seed = permute(seed + relBlockInChunk.z);
+		seed = permute(seed + blockFace.getId());
+		
+		float x = (float) getDouble(seed) * 0.8f - 0.4f;
+		seed = permute(seed);
+		float y = (float) getDouble(seed) * 0.8f - 0.4f;
+		seed = permute(seed);
+		float size = (float) getDouble(seed) * 0.5f + 0.5f;
+		seed = permute(seed);
+		double rotation = getDouble(seed) * Math.PI / 8;
+		
+		output.identity().translate(x, y, 0).scale(size).rotateZ(rotation);
+		return (count == 0) || ((count < maxCount) && (seed % 3 != 0));
+	}
+
+}

src/main/java/ru/windcorp/progressia/test/TileRenderTinyFlower.java

@@ -0,0 +1,48 @@
+/*
+ * Progressia
+ * Copyright (C)  2020-2021  Wind Corporation and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package ru.windcorp.progressia.test;
+
+import glm.mat._4.Mat4;
+import glm.vec._3.i.Vec3i;
+import ru.windcorp.progressia.client.graphics.texture.Texture;
+import ru.windcorp.progressia.common.world.DefaultChunkData;
+import ru.windcorp.progressia.common.world.rels.RelFace;
+
+public class TileRenderTinyFlower extends TileRenderHerb {
+	
+	private final float size;
+
+	public TileRenderTinyFlower(String id, Texture texture, int maxCount, float size) {
+		super(id, texture, maxCount);
+		this.size = size;
+	}
+	
+	@Override
+	protected boolean getTransform(
+		DefaultChunkData chunk,
+		Vec3i relBlockInChunk,
+		RelFace blockFace,
+		int count,
+		Mat4 output
+	) {
+		boolean result = super.getTransform(chunk, relBlockInChunk, blockFace, count, output);
+		output.scale(size);
+		return result;
+	}
+
+}

src/main/java/ru/windcorp/progressia/test/gen/Fields.java

@@ -215,20 +215,26 @@ public class Fields {
 		return tweak(f, 1, 1, bias);
 	}
 	
+	public static Field anti(Field f) {
+		return tweak(f, 1, -1, 1);
+	}
+
 	public static Field octaves(Field f, double scaleFactor, double amplitudeFactor, int octaves) {
 		return (x, y) -> {
 			double result = 0;
 
 			double scale = 1;
 			double amplitude = 1;
+			double cumulativeAmplitude = 0;
 
 			for (int i = 0; i < octaves; ++i) {
 				result += f.compute(x * scale, y * scale) * amplitude;
+				cumulativeAmplitude += amplitude;
 				scale *= scaleFactor;
 				amplitude /= amplitudeFactor;
 			}
 
-			return result;
+			return result / cumulativeAmplitude;
 		};
 	}
 

src/main/java/ru/windcorp/progressia/test/gen/TestFlowerFeature.java

@@ -0,0 +1,95 @@
+/*
+ * Progressia
+ * Copyright (C)  2020-2021  Wind Corporation and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package ru.windcorp.progressia.test.gen;
+
+import java.util.Set;
+import java.util.function.Function;
+
+import com.google.common.collect.ImmutableSet;
+
+import ru.windcorp.progressia.common.world.rels.RelFace;
+import ru.windcorp.progressia.common.world.tile.TileData;
+import ru.windcorp.progressia.common.world.tile.TileDataRegistry;
+import ru.windcorp.progressia.server.world.generation.surface.SurfaceFloatField;
+import ru.windcorp.progressia.server.world.generation.surface.SurfaceTopLayerFeature;
+import ru.windcorp.progressia.server.world.generation.surface.context.SurfaceBlockContext;
+import ru.windcorp.progressia.test.TestContent;
+
+public class TestFlowerFeature extends SurfaceTopLayerFeature {
+
+	private static class FlowerGenerator {
+		private final TileData tile;
+		private final SurfaceFloatField floweriness;
+
+		public FlowerGenerator(TileData tile, Function<String, SurfaceFloatField> flowerinessGenerator) {
+			this.tile = tile;
+			this.floweriness = flowerinessGenerator.apply(tile.getName());
+		}
+
+		public void generate(SurfaceBlockContext context) {
+			if (context.getRandom().nextDouble() < floweriness.get(context)) {
+				context.addTile(RelFace.UP, tile);
+			}
+		}
+	}
+
+	private final Set<String> soilWhitelist;
+	{
+		ImmutableSet.Builder<String> b = ImmutableSet.builder();
+		b.add("Test:Dirt", "Test:Stone");
+		TestContent.ROCKS.getRocks().forEach(rock -> rock.getBlocks().forEach(block -> b.add(block.getId())));
+		soilWhitelist = b.build();
+	}
+
+	private final FlowerGenerator[] flowers;
+
+	public TestFlowerFeature(String id, Function<String, SurfaceFloatField> flowerinessGenerator) {
+		super(id);
+
+		this.flowers = TileDataRegistry.getInstance().values().stream()
+			.filter(tile -> tile.getName().endsWith("Flowers"))
+			.map(tile -> new FlowerGenerator(tile, flowerinessGenerator))
+			.toArray(FlowerGenerator[]::new);
+	}
+
+	@Override
+	protected void processTopBlock(SurfaceBlockContext context) {
+		if (context.getLocation().z < 0) {
+			return;
+		}
+		if (!soilWhitelist.contains(context.getBlock().getId())) {
+			return;
+		}
+
+		if (!context.pushRelative(RelFace.UP).logic().getBlock().isTransparent()) {
+			context.pop();
+			return;
+		}
+		context.pop();
+
+		for (FlowerGenerator flower : flowers) {
+			flower.generate(context);
+		}
+	}
+
+	@Override
+	protected boolean isSolid(SurfaceBlockContext context) {
+		return context.logic().getBlock().isSolid(RelFace.UP);
+	}
+
+}

src/main/java/ru/windcorp/progressia/test/gen/TestGenerationConfig.java

@@ -76,7 +76,7 @@ public class TestGenerationConfig {
 		BlockData dirt = BlockDataRegistry.getInstance().get("Test:Dirt");
 		BlockData air = BlockDataRegistry.getInstance().get("Test:Air");
 
-		SurfaceFloatField cliffs = FIELDS.get("Test:CliffSelector");
+		SurfaceFloatField cliffs = FIELDS.get("Test:Cliff");
 
 		WorleyProceduralNoise.Builder<TerrainLayer> builder = WorleyProceduralNoise.builder();
 		TestContent.ROCKS.getRocks().forEach(rock -> {
@@ -108,21 +108,32 @@ public class TestGenerationConfig {
 	private static void registerFeatures(List<SurfaceFeature> features) {
 
 		SurfaceFloatField forestiness = FIELDS.register(
-			"Test:Forestiness",
+			"Test:Forest",
 			() -> squash(scale(FIELDS.primitive(), 200), 5)
 		);
 		
-		SurfaceFloatField floweriness = FIELDS.register(
-			"Test:Floweriness",
+		SurfaceFloatField grassiness = FIELDS.register(
+			"Test:Grass",
 			f -> multiply(
-				scale(octaves(FIELDS.primitive(), 2, 2), 40),
-				tweak(FIELDS.get("Test:Forestiness", f), 1, -1, 1.1)
+				tweak(octaves(FIELDS.primitive(), 2, 2), 40, 0.5, 1.2),
+				squash(tweak(FIELDS.get("Test:Forest", f), 1, -0.7, 1), 10),
+				anti(squash(FIELDS.get("Test:Cliff", f), 10))
+			)
+		);
+
+		Function<String, SurfaceFloatField> floweriness = flowerName -> FIELDS.register(
+			"Test:Flower" + flowerName,
+			f -> multiply(
+				selectPositive(squash(scale(octaves(FIELDS.primitive(), 2, 3), 100), 2), 1, 0.5),
+				tweak(FIELDS.get("Test:Forest", f), 1, -1, 1.1),
+				anti(squash(FIELDS.get("Test:Cliff", f), 10))
 			)
 		);
 
 		features.add(new TestBushFeature("Test:BushFeature", forestiness));
 		features.add(new TestTreeFeature("Test:TreeFeature", forestiness));
-		features.add(new TestGrassFeature("Test:GrassFeature", FIELDS.get("Test:CliffSelector"), floweriness));
+		features.add(new TestGrassFeature("Test:GrassFeature", grassiness));
+		features.add(new TestFlowerFeature("Test:FlowerFeature", floweriness));
 	}
 
 }

src/main/java/ru/windcorp/progressia/test/gen/TestGrassFeature.java

@@ -23,40 +23,47 @@ import java.util.Set;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 
+import ru.windcorp.progressia.common.util.ArrayFloatRangeMap;
+import ru.windcorp.progressia.common.util.FloatRangeMap;
 import ru.windcorp.progressia.common.world.rels.RelFace;
 import ru.windcorp.progressia.common.world.tile.TileData;
 import ru.windcorp.progressia.common.world.tile.TileDataRegistry;
 import ru.windcorp.progressia.server.world.generation.surface.SurfaceFloatField;
 import ru.windcorp.progressia.server.world.generation.surface.SurfaceTopLayerFeature;
 import ru.windcorp.progressia.server.world.generation.surface.context.SurfaceBlockContext;
+import ru.windcorp.progressia.test.TestContent;
 
 public class TestGrassFeature extends SurfaceTopLayerFeature {
 
-	private static final Set<String> WHITELIST = ImmutableSet.of(
-		"Test:Dirt",
-		"Test:Stone",
-		"Test:GraniteMonolith",
-		"Test:GraniteCracked",
-		"Test:GraniteGravel"
-	);
+	private final Set<String> soilWhitelist;
+	{
+		ImmutableSet.Builder<String> b = ImmutableSet.builder();
+		b.add("Test:Dirt", "Test:Stone");
+		TestContent.ROCKS.getRocks().forEach(rock -> rock.getBlocks().forEach(block -> b.add(block.getId())));
+		soilWhitelist = b.build();
+	}
 
 	private final SurfaceFloatField grassiness;
-	private final SurfaceFloatField floweriness;
 	private final double scatterDensity = 1.0 / (3 * 3);
 
 	private final TileData grass = TileDataRegistry.getInstance().get("Test:Grass");
-	private final List<TileData> flowers = ImmutableList.of(
-		TileDataRegistry.getInstance().get("Test:YellowFlowers")
-	);
+
+	private final FloatRangeMap<TileData> grasses = new ArrayFloatRangeMap<>();
+	{
+		grasses.put(0.6f, 1, TileDataRegistry.getInstance().get("Test:TallGrass"));
+		grasses.put(0.4f, 0.6f, TileDataRegistry.getInstance().get("Test:MediumGrass"));
+		grasses.put(0.1f, 0.4f, TileDataRegistry.getInstance().get("Test:LowGrass"));
+	}
+
 	private final List<TileData> scatter = ImmutableList.of(
 		TileDataRegistry.getInstance().get("Test:Stones"),
-		TileDataRegistry.getInstance().get("Test:Sand")
+		TileDataRegistry.getInstance().get("Test:Sand"),
+		TileDataRegistry.getInstance().get("Test:Bush")
 	);
 
-	public TestGrassFeature(String id, SurfaceFloatField grassiness, SurfaceFloatField floweriness) {
+	public TestGrassFeature(String id, SurfaceFloatField grassiness) {
 		super(id);
 		this.grassiness = grassiness;
-		this.floweriness = floweriness;
 	}
 
 	@Override
@@ -64,7 +71,7 @@ public class TestGrassFeature extends SurfaceTopLayerFeature {
 		if (context.getLocation().z < 0) {
 			return;
 		}
-		if (!WHITELIST.contains(context.getBlock().getId())) {
+		if (!soilWhitelist.contains(context.getBlock().getId())) {
 			return;
 		}
 
@@ -75,15 +82,11 @@ public class TestGrassFeature extends SurfaceTopLayerFeature {
 		context.pop();
 
 		double grassiness = this.grassiness.get(context);
-		if (grassiness < 0.2) {
-			growGrass(context);
+		if (grassiness > 0.1) {
+			growGrass(context, grassiness);
 		}
 
 		placeScatter(context);
-		
-		if (grassiness < 0.2) {
-			growFlowers(context);
-		}
 	}
 
 	private void placeScatter(SurfaceBlockContext context) {
@@ -93,9 +96,10 @@ public class TestGrassFeature extends SurfaceTopLayerFeature {
 		}
 	}
 
-	private void growGrass(SurfaceBlockContext context) {
+	private void growGrass(SurfaceBlockContext context, double grassiness) {
 		for (RelFace face : RelFace.getFaces()) {
-			if (face == RelFace.DOWN) continue;
+			if (face == RelFace.DOWN)
+				continue;
 
 			if (context.pushRelative(face).logic().getBlock().isTransparent()) {
 				context.pop();
@@ -105,12 +109,12 @@ public class TestGrassFeature extends SurfaceTopLayerFeature {
 			}
 
 		}
-	}
 
-	private void growFlowers(SurfaceBlockContext context) {
-		if (context.getRandom().nextDouble() < floweriness.get(context)) {
-			TileData tile = pickRandom(context, flowers);
-			context.addTile(RelFace.UP, tile);
+		if (context.getRandom().nextDouble() < grassiness) {
+			TileData herbGrass = grasses.get((float) grassiness);
+			if (herbGrass != null) {
+				context.addTile(RelFace.UP, herbGrass);
+			}
 		}
 	}
 

src/main/java/ru/windcorp/progressia/test/gen/TestHeightMap.java

@@ -54,9 +54,9 @@ public class TestHeightMap implements SurfaceFloatField {
 				tweak(octaves(fields.primitive(), 2, 3), 50, 0.2)
 			);
 			
-			fields.register("Test:CliffSelector", face, multiply(
+			fields.register("Test:Cliff", face, multiply(
 				shoreCliffSelector,
-				bias(select(shoreCliffs, 0, 0.07), 0)
+				select(shoreCliffs, 0, 0.07)
 			));
 			
 			fields.register("Test:Height", face, cutoff(add(