Added a rainboom ability for pegasi

src/main/java/com/minelittlepony/unicopia/UTags.java

@@ -1,6 +1,7 @@
 package com.minelittlepony.unicopia;
 
 import net.fabricmc.fabric.api.tag.TagRegistry;
+import net.minecraft.block.Block;
 import net.minecraft.item.Item;
 import net.minecraft.tag.Tag;
 import net.minecraft.util.Identifier;
@@ -13,6 +14,8 @@ public interface UTags {
     Tag<Item> FAIRLY_TOXIC = register("fairly_toxic");
     Tag<Item> SEVERELY_TOXIC = register("severely_toxic");
 
+    Tag<Block> FRAGILE = TagRegistry.block(new Identifier("unicopia", "fragile"));
+
     static Tag<Item> register(String name) {
         return TagRegistry.item(new Identifier("unicopia", name));
     }

src/main/java/com/minelittlepony/unicopia/ability/Abilities.java

@@ -24,6 +24,9 @@ public interface Abilities {
     Ability<?> GROW = register(new EarthPonyGrowAbility(), "grow", AbilitySlot.SECONDARY);
     Ability<?> STOMP = register(new EarthPonyStompAbility(), "stomp", AbilitySlot.TERTIARY);
 
+    // pegasus
+    Ability<?> RAINBOOM = register(new PegasusRainboomAbility(), "rainboom", AbilitySlot.PRIMARY);
+
     // pegasus / bat / alicorn / changeling
     Ability<?> CARRY = register(new CarryAbility(), "carry", AbilitySlot.PASSIVE);
 

src/main/java/com/minelittlepony/unicopia/ability/PegasusRainboomAbility.java

@@ -0,0 +1,83 @@
+package com.minelittlepony.unicopia.ability;
+
+import javax.annotation.Nullable;
+
+import com.minelittlepony.unicopia.Race;
+import com.minelittlepony.unicopia.ability.data.Hit;
+import com.minelittlepony.unicopia.ability.magic.spell.JoustingSpell;
+import com.minelittlepony.unicopia.entity.player.Pony;
+import com.minelittlepony.unicopia.particle.MagicParticleEffect;
+import com.minelittlepony.unicopia.particle.OrientedBillboardParticleEffect;
+import com.minelittlepony.unicopia.particle.UParticles;
+
+import net.minecraft.util.math.Vec3d;
+
+/**
+ * Changeling ability to restore health from mobs
+ */
+public class PegasusRainboomAbility implements Ability<Hit> {
+
+    @Override
+    public int getWarmupTime(Pony player) {
+        return 59;
+    }
+
+    @Override
+    public int getCooldownTime(Pony player) {
+        return 60;
+    }
+
+    @Override
+    public boolean canUse(Race race) {
+        return race.canInteractWithClouds();
+    }
+
+    @Nullable
+    @Override
+    public Hit tryActivate(Pony player) {
+
+        if (!player.getMaster().isCreative() && player.getMagicalReserves().getMana().getPercentFill() < 0.2F) {
+            return null;
+        }
+
+        if (player.getPhysics().isFlying() && !player.hasSpell()) {
+            return Hit.INSTANCE;
+        }
+
+        return null;
+    }
+
+    @Override
+    public Hit.Serializer<Hit> getSerializer() {
+        return Hit.SERIALIZER;
+    }
+
+    @Override
+    public double getCostEstimate(Pony player) {
+        return player.getMagicalReserves().getMana().getMax() * 0.9F;
+    }
+
+    @Override
+    public void apply(Pony player, Hit data) {
+
+        if (!player.getMaster().isCreative() && player.getMagicalReserves().getMana().getPercentFill() < 0.2F) {
+            return;
+        }
+
+        if (player.getPhysics().isFlying() && !player.hasSpell()) {
+            player.getMagicalReserves().getMana().multiply(0.1F);
+            player.addParticle(new OrientedBillboardParticleEffect(UParticles.RAINBOOM_RING, player.getPhysics().getMotionAngle()), player.getOriginVector(), Vec3d.ZERO);
+            player.setSpell(new JoustingSpell());
+        }
+    }
+
+    @Override
+    public void preApply(Pony player, AbilitySlot slot) {
+        player.getMagicalReserves().getExertion().add(6);
+    }
+
+    @Override
+    public void postApply(Pony player, AbilitySlot slot) {
+        player.spawnParticles(MagicParticleEffect.UNICORN, 5);
+    }
+}

src/main/java/com/minelittlepony/unicopia/ability/magic/Caster.java

@@ -6,6 +6,7 @@ import java.util.stream.Stream;
 import javax.annotation.Nullable;
 
 import com.minelittlepony.unicopia.Owned;
+import com.minelittlepony.unicopia.entity.Physics;
 import com.minelittlepony.unicopia.network.EffectSync;
 import com.minelittlepony.unicopia.particle.ParticleSource;
 import com.minelittlepony.unicopia.util.VecHelper;
@@ -21,6 +22,8 @@ import net.minecraft.world.World;
  */
 public interface Caster<E extends LivingEntity> extends Owned<E>, Levelled, Affine, Magical, ParticleSource {
 
+    Physics getPhysics();
+
     EffectSync getPrimarySpellSlot();
 
     default void setSpell(@Nullable Spell spell) {

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/JoustingSpell.java

@@ -0,0 +1,111 @@
+package com.minelittlepony.unicopia.ability.magic.spell;
+
+import com.minelittlepony.unicopia.Affinity;
+import com.minelittlepony.unicopia.UTags;
+import com.minelittlepony.unicopia.ability.magic.Caster;
+import com.minelittlepony.unicopia.ability.magic.Thrown;
+import com.minelittlepony.unicopia.entity.player.Pony;
+import com.minelittlepony.unicopia.particle.OrientedBillboardParticleEffect;
+import com.minelittlepony.unicopia.particle.ParticleHandle;
+import com.minelittlepony.unicopia.particle.UParticles;
+import com.minelittlepony.unicopia.util.MagicalDamageSource;
+import com.minelittlepony.unicopia.util.PosHelper;
+import com.minelittlepony.unicopia.util.shape.Shape;
+import com.minelittlepony.unicopia.util.shape.Sphere;
+
+import net.minecraft.block.BlockState;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.Vec3d;
+import net.minecraft.world.GameRules;
+
+public class JoustingSpell extends AbstractRangedAreaSpell implements Thrown {
+
+    private final int rad = 5;
+    private final Shape effect_range = new Sphere(false, rad);
+
+    private final ParticleHandle particlEffect = new ParticleHandle();
+
+    private int age;
+
+    @Override
+    public String getName() {
+        return "joust";
+    }
+
+    @Override
+    public Affinity getAffinity() {
+        return Affinity.GOOD;
+    }
+
+    @Override
+    public int getTint() {
+        return 0xBDBDF9;
+    }
+
+    @Override
+    public void setDead() {
+        super.setDead();
+        particlEffect.destroy();
+    }
+
+    @Override
+    public boolean update(Caster<?> source) {
+        LivingEntity owner = source.getMaster();
+
+        source.findAllEntitiesInRange(rad).forEach(e -> {
+            e.damage(MagicalDamageSource.create("rainboom", owner), 6);
+        });
+        PosHelper.getAllInRegionMutable(source.getOrigin(), effect_range).forEach(pos -> {
+            BlockState state = source.getWorld().getBlockState(pos);
+            if (state.isIn(UTags.FRAGILE) && canBreak(pos, owner)) {
+                owner.world.breakBlock(pos, true);
+            }
+        });
+
+        Vec3d motion = source.getEntity().getRotationVec(1).multiply(1.5);
+        Vec3d velocity = source.getEntity().getVelocity().add(motion);
+
+        while (velocity.length() > 3) {
+            velocity = velocity.multiply(0.6);
+        }
+
+        source.getEntity().setVelocity(velocity);
+        if (source instanceof Pony) {
+            ((Pony)source).getMagicalReserves().getEnergy().multiply(0.2F);
+        }
+
+        return !source.getEntity().removed && age++ < 90 + 7 * (source.getLevel().get() + 1);
+    }
+
+    private boolean canBreak(BlockPos pos, LivingEntity entity) {
+
+        if (entity instanceof PlayerEntity) {
+            return entity.world.canPlayerModifyAt((PlayerEntity)entity, pos);
+        }
+
+        return entity.world.getGameRules().getBoolean(GameRules.DO_MOB_GRIEFING);
+    }
+
+    @Override
+    public void render(Caster<?> source) {
+        particlEffect.ifAbsent(source, spawner -> {
+            spawner.addParticle(UParticles.RAINBOOM_TRAIL, source.getOriginVector(), Vec3d.ZERO);
+            spawner.addParticle(new OrientedBillboardParticleEffect(UParticles.RAINBOOM_RING, source.getPhysics().getMotionAngle()), source.getOriginVector(), Vec3d.ZERO);
+        }).ifPresent(p -> p.attach(source));
+    }
+
+    @Override
+    public void toNBT(CompoundTag compound) {
+        super.toNBT(compound);
+        compound.putInt("age", age);
+    }
+
+    @Override
+    public void fromNBT(CompoundTag compound) {
+        super.fromNBT(compound);
+        age = compound.getInt("age");
+    }
+}

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/SpellRegistry.java

@@ -39,6 +39,7 @@ public class SpellRegistry {
         register(RevealingSpell::new);
         register(ScorchSpell::new);
         register(DisguiseSpell::new);
+        register(JoustingSpell::new);
     }
 
     @Nullable

src/main/java/com/minelittlepony/unicopia/client/URenderers.java

@@ -5,6 +5,7 @@ import com.minelittlepony.unicopia.client.particle.ChangelingMagicParticle;
 import com.minelittlepony.unicopia.client.particle.DiskParticle;
 import com.minelittlepony.unicopia.client.particle.MagicParticle;
 import com.minelittlepony.unicopia.client.particle.RainboomParticle;
+import com.minelittlepony.unicopia.client.particle.RainbowTrailParticle;
 import com.minelittlepony.unicopia.client.particle.RaindropsParticle;
 import com.minelittlepony.unicopia.client.particle.SphereParticle;
 import com.minelittlepony.unicopia.particle.UParticles;
@@ -24,6 +25,7 @@ public interface URenderers {
         ParticleFactoryRegistry.getInstance().register(UParticles.CHANGELING_MAGIC, createFactory(ChangelingMagicParticle::new));
         ParticleFactoryRegistry.getInstance().register(UParticles.RAIN_DROPS, createFactory(RaindropsParticle::new));
         ParticleFactoryRegistry.getInstance().register(UParticles.RAINBOOM_RING, RainboomParticle::new);
+        ParticleFactoryRegistry.getInstance().register(UParticles.RAINBOOM_TRAIL, RainbowTrailParticle::new);
         ParticleFactoryRegistry.getInstance().register(UParticles.SPHERE, SphereParticle::new);
         ParticleFactoryRegistry.getInstance().register(UParticles.DISK, DiskParticle::new);
 

src/main/java/com/minelittlepony/unicopia/client/particle/AbstractBillboardParticle.java

@@ -0,0 +1,88 @@
+package com.minelittlepony.unicopia.client.particle;
+
+import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.systems.RenderSystem;
+
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.particle.Particle;
+import net.minecraft.client.particle.ParticleTextureSheet;
+import net.minecraft.client.render.BufferBuilder;
+import net.minecraft.client.render.Camera;
+import net.minecraft.client.render.Tessellator;
+import net.minecraft.client.render.VertexConsumer;
+import net.minecraft.client.render.VertexFormats;
+import net.minecraft.client.util.math.Vector3f;
+import net.minecraft.client.world.ClientWorld;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.math.MathHelper;
+import net.minecraft.util.math.Vec3d;
+
+public abstract class AbstractBillboardParticle extends Particle {
+
+    protected float scale = 1;
+
+    public AbstractBillboardParticle(ClientWorld world, double x, double y, double z, double velocityX, double velocityY, double velocityZ) {
+        super(world, x, y, z, velocityX, velocityY, velocityZ);
+
+    }
+
+    @Override
+    public ParticleTextureSheet getType() {
+        return ParticleTextureSheet.CUSTOM;
+    }
+
+    @Override
+    public void buildGeometry(VertexConsumer drawer, Camera camera, float tickDelta) {
+        Tessellator te = Tessellator.getInstance();
+        BufferBuilder buffer = te.getBuffer();
+
+        MinecraftClient.getInstance().getTextureManager().bindTexture(getTexture());
+
+        RenderSystem.disableCull();
+        RenderSystem.enableBlend();
+        RenderSystem.blendFuncSeparate(
+                GlStateManager.SrcFactor.SRC_ALPHA, GlStateManager.DstFactor.ONE_MINUS_SRC_ALPHA,
+                GlStateManager.SrcFactor.ONE, GlStateManager.DstFactor.ONE_MINUS_SRC_ALPHA
+        );
+        RenderSystem.alphaFunc(516, 0.003921569F);
+
+
+        Vec3d cam = camera.getPos();
+
+        float renderX = (float)(MathHelper.lerp(tickDelta, prevPosX, x) - cam.getX());
+        float renderY = (float)(MathHelper.lerp(tickDelta, prevPosY, y) - cam.getY());
+        float renderZ = (float)(MathHelper.lerp(tickDelta, prevPosZ, z) - cam.getZ());
+
+        renderQuads(te, buffer, renderX, renderY, renderZ, tickDelta);
+
+        RenderSystem.enableCull();
+        RenderSystem.defaultAlphaFunc();
+        RenderSystem.defaultBlendFunc();
+    }
+
+    protected abstract void renderQuads(Tessellator te, BufferBuilder buffer, float x, float y, float z, float tickDelta);
+
+    protected void renderQuad(Tessellator te, BufferBuilder buffer, Vector3f[] corners, float alpha, float tickDelta) {
+        int light = getColorMultiplier(tickDelta);
+
+        buffer.begin(7, VertexFormats.POSITION_TEXTURE_COLOR_LIGHT);
+        buffer.vertex(corners[0].getX(), corners[0].getY(), corners[0].getZ()).texture(0, 0).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
+        buffer.vertex(corners[1].getX(), corners[1].getY(), corners[1].getZ()).texture(1, 0).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
+        buffer.vertex(corners[2].getX(), corners[2].getY(), corners[2].getZ()).texture(1, 1).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
+        buffer.vertex(corners[3].getX(), corners[3].getY(), corners[3].getZ()).texture(0, 1).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
+
+        te.draw();
+    }
+
+    protected abstract Identifier getTexture();
+
+    public float getScale(float tickDelta) {
+       return scale;
+    }
+
+    @Override
+    public Particle scale(float scale) {
+       this.scale = scale;
+       return super.scale(scale);
+    }
+}

src/main/java/com/minelittlepony/unicopia/client/particle/OrientedBillboardParticle.java

@@ -0,0 +1,58 @@
+package com.minelittlepony.unicopia.client.particle;
+
+import com.minelittlepony.unicopia.particle.OrientedBillboardParticleEffect;
+
+import net.minecraft.client.render.BufferBuilder;
+import net.minecraft.client.render.Camera;
+import net.minecraft.client.render.Tessellator;
+import net.minecraft.client.render.VertexConsumer;
+import net.minecraft.client.util.math.Vector3f;
+import net.minecraft.client.world.ClientWorld;
+import net.minecraft.util.math.Quaternion;
+
+public abstract class OrientedBillboardParticle extends AbstractBillboardParticle {
+
+    protected boolean fixed;
+    protected Quaternion rotation = new Quaternion(0, 0, 0, 1);
+
+    public OrientedBillboardParticle(OrientedBillboardParticleEffect effect, ClientWorld world, double x, double y, double z, double velocityX, double velocityY, double velocityZ) {
+        super(world, x, y, z, velocityX, velocityY, velocityZ);
+
+        fixed = effect.isAngleFixed();
+        if (!fixed) {
+            rotation.hamiltonProduct(Vector3f.POSITIVE_X.getDegreesQuaternion(180 - effect.getYaw()));
+            rotation.hamiltonProduct(Vector3f.POSITIVE_Y.getDegreesQuaternion(effect.getPitch()));
+        }
+    }
+
+    @Override
+    public void buildGeometry(VertexConsumer drawer, Camera camera, float tickDelta) {
+        if (fixed) {
+            rotation = camera.getRotation();
+        }
+        super.buildGeometry(drawer, camera, tickDelta);
+    }
+
+    @Override
+    protected void renderQuads(Tessellator te, BufferBuilder buffer, float x, float y, float z, float tickDelta) {
+        Vector3f[] corners = new Vector3f[]{
+                new Vector3f(-1, -1, 0),
+                new Vector3f(-1,  1, 0),
+                new Vector3f( 1,  1, 0),
+                new Vector3f( 1, -1, 0)
+        };
+        float scale = getScale(tickDelta);
+
+        for(int k = 0; k < 4; ++k) {
+           Vector3f corner = corners[k];
+           corner.rotate(rotation);
+           corner.scale(scale);
+           corner.add(x, y, z);
+        }
+
+        float alpha = colorAlpha * (1 - ((float)age / maxAge));
+
+        renderQuad(te, buffer, corners, alpha, tickDelta);
+    }
+
+}

src/main/java/com/minelittlepony/unicopia/client/particle/RainboomParticle.java

@@ -1,111 +1,32 @@
 package com.minelittlepony.unicopia.client.particle;
 
-import com.mojang.blaze3d.platform.GlStateManager;
+import com.minelittlepony.unicopia.particle.OrientedBillboardParticleEffect;
-import com.mojang.blaze3d.systems.RenderSystem;
 
-import net.minecraft.client.MinecraftClient;
-import net.minecraft.client.particle.Particle;
-import net.minecraft.client.particle.ParticleTextureSheet;
-import net.minecraft.client.render.BufferBuilder;
-import net.minecraft.client.render.Camera;
-import net.minecraft.client.render.Tessellator;
-import net.minecraft.client.render.VertexConsumer;
-import net.minecraft.client.render.VertexFormats;
-import net.minecraft.client.util.math.Vector3f;
 import net.minecraft.client.world.ClientWorld;
-import net.minecraft.particle.DefaultParticleType;
 import net.minecraft.sound.SoundCategory;
 import net.minecraft.sound.SoundEvents;
 import net.minecraft.util.Identifier;
 import net.minecraft.util.math.MathHelper;
-import net.minecraft.util.math.Quaternion;
-import net.minecraft.util.math.Vec3d;
-
-public class RainboomParticle extends Particle {
 
+public class RainboomParticle extends OrientedBillboardParticle {
     private static final Identifier TEXTURE = new Identifier("unicopia", "textures/particles/rainboom_ring.png");
 
     protected float prevBaseSize = 0;
     protected float baseSize = 0;
-    protected float scale = 1;
 
-    protected Quaternion rotation;
+    public RainboomParticle(OrientedBillboardParticleEffect effect, ClientWorld world, double x, double y, double z, double velocityX, double velocityY, double velocityZ) {
-
+        super(effect, world, x, y, z, velocityX, velocityY, velocityZ);
-    public RainboomParticle(DefaultParticleType effect, ClientWorld world, double x, double y, double z, double angleX, double angleY, double angleZ) {
-        super(world, x, y, z);
-
-        rotation = Vector3f.POSITIVE_X.getRadialQuaternion((float)angleX);
-        rotation.hamiltonProduct(Vector3f.POSITIVE_Y.getRadialQuaternion((float)angleY));
-        rotation.hamiltonProduct(Vector3f.POSITIVE_Z.getRadialQuaternion((float)angleZ));
         setMaxAge(40);
     }
 
     @Override
-    public ParticleTextureSheet getType() {
+    public float getScale(float tickDelta) {
-        return ParticleTextureSheet.CUSTOM;
+       return MathHelper.lerp(tickDelta, prevBaseSize, baseSize) * super.getScale(tickDelta);
     }
 
     @Override
-    public void buildGeometry(VertexConsumer drawer, Camera camera, float tickDelta) {
+    protected Identifier getTexture() {
-        Vec3d cam = camera.getPos();
+        return TEXTURE;
-
-        float renderX = (float)(MathHelper.lerp(tickDelta, prevPosX, x) - cam.getX());
-        float renderY = (float)(MathHelper.lerp(tickDelta, prevPosY, y) - cam.getY());
-        float renderZ = (float)(MathHelper.lerp(tickDelta, prevPosZ, z) - cam.getZ());
-
-        Vector3f[] corners = new Vector3f[]{
-                new Vector3f(-1.0F, -1.0F, 0.0F),
-                new Vector3f(-1.0F, 1.0F, 0.0F),
-                new Vector3f(1.0F, 1.0F, 0.0F),
-                new Vector3f(1.0F, -1.0F, 0.0F)
-        };
-        float scale = getSize(tickDelta);
-
-        for(int k = 0; k < 4; ++k) {
-           Vector3f corner = corners[k];
-           corner.rotate(rotation);
-           corner.scale(scale);
-           corner.add(renderX, renderY, renderZ);
-        }
-
-        float alpha = colorAlpha * (1 - ((float)age / maxAge));
-
-        int light = getColorMultiplier(tickDelta);
-
-        Tessellator te = Tessellator.getInstance();
-        BufferBuilder buffer = te.getBuffer();
-
-        MinecraftClient.getInstance().getTextureManager().bindTexture(TEXTURE);
-
-        RenderSystem.disableCull();
-        RenderSystem.enableBlend();
-        RenderSystem.blendFuncSeparate(
-                GlStateManager.SrcFactor.SRC_ALPHA, GlStateManager.DstFactor.ONE_MINUS_SRC_ALPHA,
-                GlStateManager.SrcFactor.ONE, GlStateManager.DstFactor.ONE_MINUS_SRC_ALPHA
-        );
-        RenderSystem.alphaFunc(516, 0.003921569F);
-
-        buffer.begin(7, VertexFormats.POSITION_TEXTURE_COLOR_LIGHT);
-        buffer.vertex(corners[0].getX(), corners[0].getY(), corners[0].getZ()).texture(0, 0).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
-        buffer.vertex(corners[1].getX(), corners[1].getY(), corners[1].getZ()).texture(1, 0).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
-        buffer.vertex(corners[2].getX(), corners[2].getY(), corners[2].getZ()).texture(0, 0).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
-        buffer.vertex(corners[3].getX(), corners[3].getY(), corners[3].getZ()).texture(0, 1).color(colorRed, colorGreen, colorBlue, alpha).light(light).next();
-
-        te.draw();
-
-        RenderSystem.enableCull();
-        RenderSystem.defaultAlphaFunc();
-        RenderSystem.defaultBlendFunc();
-    }
-
-    public float getSize(float tickDelta) {
-       return MathHelper.lerp(tickDelta, prevBaseSize, baseSize) * scale;
-    }
-
-    @Override
-    public Particle scale(float scale) {
-       this.scale = scale;
-       return super.scale(scale);
     }
 
     @Override
@@ -115,9 +36,9 @@ public class RainboomParticle extends Particle {
         prevBaseSize = baseSize;
         baseSize++;
 
-        if (this.age == 1) {
+        if (age == 1) {
-            this.world.playSound(x, y, z, SoundEvents.ENTITY_LIGHTNING_BOLT_THUNDER, SoundCategory.AMBIENT, 5, 0.3F, true);
+            world.playSound(x, y, z, SoundEvents.ENTITY_LIGHTNING_BOLT_THUNDER, SoundCategory.AMBIENT, 5, 0.3F, true);
-            this.world.playSound(x, y, z, SoundEvents.ENTITY_LIGHTNING_BOLT_THUNDER, SoundCategory.AMBIENT, 10, 1.3F, true);
+            world.playSound(x, y, z, SoundEvents.ENTITY_LIGHTNING_BOLT_THUNDER, SoundCategory.AMBIENT, 10, 1.3F, true);
         }
     }
 }

src/main/java/com/minelittlepony/unicopia/client/particle/RainbowTrailParticle.java

@@ -0,0 +1,147 @@
+package com.minelittlepony.unicopia.client.particle;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.minelittlepony.unicopia.ability.magic.Caster;
+import com.minelittlepony.unicopia.entity.player.Pony;
+import com.minelittlepony.unicopia.particle.ParticleHandle.Attachment;
+import com.minelittlepony.unicopia.particle.ParticleHandle.Link;
+
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.render.BufferBuilder;
+import net.minecraft.client.render.Tessellator;
+import net.minecraft.client.util.math.Vector3f;
+import net.minecraft.client.world.ClientWorld;
+import net.minecraft.particle.DefaultParticleType;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.math.Vec3d;
+
+public class RainbowTrailParticle extends AbstractBillboardParticle implements Attachment {
+    private static final Identifier TEXTURE = new Identifier("unicopia", "textures/particles/rainboom_trail.png");
+
+    private final List<Segment> segments = new ArrayList<>();
+
+    private final Link link = new Link();
+
+    public RainbowTrailParticle(DefaultParticleType effect, ClientWorld world, double x, double y, double z, double velocityX, double velocityY, double velocityZ) {
+        super(world, x, y, z, velocityX, velocityY, velocityZ);
+        segments.add(new Segment(new Vec3d(x, y, z)));
+    }
+
+    @Override
+    protected Identifier getTexture() {
+        return TEXTURE;
+    }
+
+    @Override
+    public boolean isStillAlive() {
+        return age < (maxAge - 1);
+    }
+
+    @Override
+    public void attach(Caster<?> caster) {
+        link.attach(caster);
+    }
+
+    @Override
+    public void detach() {
+        link.detach();
+    }
+
+    @Override
+    public void setAttribute(int key, Object value) {
+
+    }
+
+    @Override
+    protected void renderQuads(Tessellator te, BufferBuilder buffer, float x, float y, float z, float tickDelta) {
+        for (int i = 0; i < segments.size() - 1; i++) {
+            Vector3f[] corners = segments.get(i).getPlane(segments.get(i + 1));
+            float scale = getScale(tickDelta);
+
+            for (int k = 0; k < 4; ++k) {
+               Vector3f corner = corners[k];
+               corner.scale(scale);
+               corner.add(x, y, z);
+            }
+
+            renderQuad(te, buffer, corners, segments.get(i).getAlpha(), tickDelta);
+        }
+    }
+
+    private void follow(Caster<?> caster) {
+        Vec3d next = caster.getOriginVector();
+
+        if (segments.isEmpty()) {
+            segments.add(new Segment(next));
+        } else {
+            Vec3d last = segments.get(segments.size() - 1).position;
+            if (next.distanceTo(last) > 0.2) {
+                segments.add(new Segment(next));
+            }
+        }
+    }
+
+    @Override
+    public void tick() {
+        super.tick();
+        age = 0;
+
+        if (link.linked()) {
+            link.ifAbsent(() -> {}).ifPresent(this::follow);
+        } else {
+            follow(Pony.of(MinecraftClient.getInstance().player));
+        }
+
+        if (segments.size() > 1) {
+            segments.removeIf(Segment::tick);
+        }
+        if (segments.isEmpty()) {
+            markDead();
+        }
+    }
+
+    private final class Segment {
+        Vec3d position;
+        Vector3f offset;
+
+        int age;
+        int maxAge;
+
+        Segment(Vec3d position) {
+            this.position = position;
+            this.offset = new Vector3f((float)(position.getX() - x), (float)(position.getY() - y), (float)(position.getZ() - z));
+            this.maxAge = 90;
+        }
+
+        float getAlpha() {
+            return colorAlpha * (1 - ((float)age / maxAge));
+        }
+
+        boolean tick() {
+            return segments.indexOf(this) < segments.size() - 1 && age++ >= maxAge;
+        }
+
+        Vector3f[] getPlane(Segment to) {
+            float fromX = offset.getX();
+            float toX = to.offset.getX();
+
+            float fromZ = offset.getZ();
+            float toZ = to.offset.getZ();
+
+            float fromTopY = offset.getY() + 1;
+            float fromBottomY = offset.getY();
+
+            float toTopY = to.offset.getY() + 1;
+            float toBottomY = to.offset.getY();
+
+            return new Vector3f[]{
+                    new Vector3f(fromX, fromBottomY, fromZ), // bottom left
+                    new Vector3f(fromX, fromTopY, fromZ), // top left
+                    new Vector3f(toX, toTopY, toZ), // top right
+                    new Vector3f(toX, toBottomY, toZ)  // bottom right
+            };
+        }
+    }
+}

src/main/java/com/minelittlepony/unicopia/entity/Creature.java

@@ -9,7 +9,6 @@ import com.minelittlepony.unicopia.ability.magic.Levelled;
 import com.minelittlepony.unicopia.ability.magic.Spell;
 import com.minelittlepony.unicopia.ability.magic.spell.SpellRegistry;
 import com.minelittlepony.unicopia.network.EffectSync;
-
 import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.data.DataTracker;
 import net.minecraft.entity.data.TrackedData;

src/main/java/com/minelittlepony/unicopia/entity/EntityPhysics.java

@@ -16,7 +16,7 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.MathHelper;
 import net.minecraft.util.math.Vec3d;
 
-public class EntityPhysics<T extends Equine<?> & Owned<? extends Entity>> implements Physics, Copieable<EntityPhysics<T>> {
+public class EntityPhysics<T extends Owned<? extends Entity>> implements Physics, Copieable<EntityPhysics<T>> {
 
     private float gravity = 1;
 
@@ -31,6 +31,11 @@ public class EntityPhysics<T extends Equine<?> & Owned<? extends Entity>> implem
         return false;
     }
 
+    @Override
+    public Vec3d getMotionAngle() {
+        return new Vec3d(pony.getMaster().getPitch(1), pony.getMaster().getYaw(1), 0);
+    }
+
     @Override
     public double calcGravity(double worldConstant) {
         return worldConstant * getGravityModifier();
@@ -94,17 +99,11 @@ public class EntityPhysics<T extends Equine<?> & Owned<? extends Entity>> implem
 
     @Override
     public void toNBT(CompoundTag compound) {
-        if (gravity != 0) {
+        compound.putFloat("gravity", gravity);
-            compound.putFloat("gravity", gravity);
-        }
     }
 
     @Override
     public void fromNBT(CompoundTag compound) {
-        if (compound.contains("gravity")) {
+        gravity = compound.getFloat("gravity");
-            gravity = compound.getFloat("gravity");
-        } else {
-            gravity = 0;
-        }
     }
 }

src/main/java/com/minelittlepony/unicopia/entity/Physics.java

@@ -3,11 +3,14 @@ package com.minelittlepony.unicopia.entity;
 import com.minelittlepony.unicopia.util.NbtSerialisable;
 
 import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.Vec3d;
 
 public interface Physics extends NbtSerialisable {
 
     double calcGravity(double worldConstant);
 
+    Vec3d getMotionAngle();
+
     float getGravityModifier();
 
     void setBaseGravityModifier(float constant);

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerPhysics.java

@@ -344,5 +344,4 @@ public class PlayerPhysics extends EntityPhysics<Pony> implements Tickable, Moti
 
         pony.getMaster().calculateDimensions();
     }
-
 }

src/main/java/com/minelittlepony/unicopia/entity/player/Pony.java

@@ -310,7 +310,6 @@ public class Pony implements Caster<PlayerEntity>, Equine<PlayerEntity>, Transmi
         prevSneaking = entity.isSneaking();
         prevLanded = entity.isOnGround();
 
-
         if (gravity.isGravityNegative() && entity.getY() > entity.world.getHeight() + 64) {
            entity.damage(DamageSource.OUT_OF_WORLD, 4.0F);
         }

src/main/java/com/minelittlepony/unicopia/particle/MagicParticleEffect.java

@@ -14,7 +14,7 @@ import net.minecraft.util.registry.Registry;
 public class MagicParticleEffect implements ParticleEffect {
 
     public static final MagicParticleEffect UNICORN = new MagicParticleEffect(false, 0, 0, 0);
-    public static final ParticleEffect.Factory<MagicParticleEffect> UNICORN_FACTORY = new ParticleEffect.Factory<MagicParticleEffect>() {
+    public static final ParticleEffect.Factory<MagicParticleEffect> FACTORY = new ParticleEffect.Factory<MagicParticleEffect>() {
         @Override
         public MagicParticleEffect read(ParticleType<MagicParticleEffect> particleType, StringReader reader) throws CommandSyntaxException {
             reader.expect(' ');

src/main/java/com/minelittlepony/unicopia/particle/OrientedBillboardParticleEffect.java

@@ -0,0 +1,83 @@
+package com.minelittlepony.unicopia.particle;
+
+import java.util.Locale;
+
+import com.mojang.brigadier.StringReader;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+
+import net.minecraft.particle.ParticleEffect;
+import net.minecraft.particle.ParticleType;
+import net.minecraft.network.PacketByteBuf;
+import net.minecraft.util.math.Vec3d;
+import net.minecraft.util.registry.Registry;
+
+public class OrientedBillboardParticleEffect implements ParticleEffect {
+    public static final ParticleEffect.Factory<OrientedBillboardParticleEffect> FACTORY = new ParticleEffect.Factory<OrientedBillboardParticleEffect>() {
+        @Override
+        public OrientedBillboardParticleEffect read(ParticleType<OrientedBillboardParticleEffect> type, StringReader reader) throws CommandSyntaxException {
+            reader.expect(' ');
+            boolean fixed = reader.readBoolean();
+            reader.expect(' ');
+            float yaw = (float)reader.readDouble();
+            reader.expect(' ');
+            float pitch = (float)reader.readDouble();
+            return new OrientedBillboardParticleEffect(type, fixed, yaw, pitch);
+        }
+
+        @Override
+        public OrientedBillboardParticleEffect read(ParticleType<OrientedBillboardParticleEffect> particleType, PacketByteBuf buf) {
+            return new OrientedBillboardParticleEffect(particleType, buf.readBoolean(), buf.readFloat(), buf.readFloat());
+        }
+    };
+
+    private final boolean fixed;
+    private final float yaw;
+    private final float pitch;
+
+    private final ParticleType<OrientedBillboardParticleEffect> type;
+
+    public OrientedBillboardParticleEffect(ParticleType<OrientedBillboardParticleEffect> type, Vec3d orientation) {
+        this(type, (float)orientation.getX(), (float)orientation.getY());
+    }
+
+    public OrientedBillboardParticleEffect(ParticleType<OrientedBillboardParticleEffect> type, float yaw, float pitch) {
+        this(type, true, yaw, pitch);
+    }
+
+    private OrientedBillboardParticleEffect(ParticleType<OrientedBillboardParticleEffect> type, boolean fixed, float yaw, float pitch) {
+        this.fixed = fixed;
+        this.yaw = yaw;
+        this.pitch = pitch;
+        this.type = type;
+    }
+
+    public boolean isAngleFixed() {
+        return fixed;
+    }
+
+    public float getYaw() {
+        return yaw;
+    }
+
+    public float getPitch() {
+        return pitch;
+    }
+
+    @Override
+    public ParticleType<?> getType() {
+        return type;
+    }
+
+    @Override
+    public void write(PacketByteBuf buf) {
+        buf.writeBoolean(fixed);
+        buf.writeFloat(yaw);
+        buf.writeFloat(pitch);
+    }
+
+    @Override
+    public String asString() {
+        return String.format(Locale.ROOT, "%s %b %.2f %.2f", Registry.PARTICLE_TYPE.getId(getType()), fixed, yaw, pitch);
+    }
+
+}

src/main/java/com/minelittlepony/unicopia/particle/ParticleHandle.java

@@ -68,6 +68,11 @@ public class ParticleHandle {
             this.effect = caster.getSpell(false).getName();
         }
 
+        public void detach() {
+            linked = false;
+            caster = Optional.empty();
+        }
+
         public boolean linked() {
             return linked;
         }

src/main/java/com/minelittlepony/unicopia/particle/UParticles.java

@@ -8,10 +8,11 @@ import net.minecraft.util.registry.Registry;
 
 public interface UParticles {
 
-    ParticleType<MagicParticleEffect> UNICORN_MAGIC = register("unicorn_magic", FabricParticleTypes.complex(MagicParticleEffect.UNICORN_FACTORY));
+    ParticleType<MagicParticleEffect> UNICORN_MAGIC = register("unicorn_magic", FabricParticleTypes.complex(MagicParticleEffect.FACTORY));
     DefaultParticleType CHANGELING_MAGIC = register("changeling_magic", FabricParticleTypes.simple());
 
-    DefaultParticleType RAINBOOM_RING = register("rainboom_ring", FabricParticleTypes.simple());
+    ParticleType<OrientedBillboardParticleEffect> RAINBOOM_RING = register("rainboom_ring", FabricParticleTypes.complex(OrientedBillboardParticleEffect.FACTORY));
+    DefaultParticleType RAINBOOM_TRAIL = register("rainboom_trail", FabricParticleTypes.simple());
 
     DefaultParticleType RAIN_DROPS = register("rain_drops", FabricParticleTypes.simple());
 

src/main/java/com/minelittlepony/unicopia/projectile/MagicProjectileEntity.java

@@ -7,6 +7,8 @@ import com.minelittlepony.unicopia.ability.magic.Magical;
 import com.minelittlepony.unicopia.ability.magic.Spell;
 import com.minelittlepony.unicopia.ability.magic.Thrown;
 import com.minelittlepony.unicopia.ability.magic.spell.SpellRegistry;
+import com.minelittlepony.unicopia.entity.EntityPhysics;
+import com.minelittlepony.unicopia.entity.Physics;
 import com.minelittlepony.unicopia.network.Channel;
 import com.minelittlepony.unicopia.network.EffectSync;
 import com.minelittlepony.unicopia.network.MsgSpawnProjectile;
@@ -49,6 +51,8 @@ public class MagicProjectileEntity extends ThrownItemEntity implements Magical,
 
     private final EffectSync effectDelegate = new EffectSync(this, EFFECT);
 
+    private final EntityPhysics<MagicProjectileEntity> physics = new EntityPhysics<>(this);
+
     private BlockPos lastBlockPos;
 
     public MagicProjectileEntity(EntityType<MagicProjectileEntity> type, World world) {
@@ -97,6 +101,11 @@ public class MagicProjectileEntity extends ThrownItemEntity implements Magical,
         return LEVELS;
     }
 
+    @Override
+    public Physics getPhysics() {
+        return physics;
+    }
+
     @Override
     public Affinity getAffinity() {
         return hasSpell() ? Affinity.NEUTRAL : getSpell(true).getAffinity();
@@ -206,7 +215,7 @@ public class MagicProjectileEntity extends ThrownItemEntity implements Magical,
     @Override
     public void readCustomDataFromTag(CompoundTag compound) {
         super.readCustomDataFromTag(compound);
-
+        physics.fromNBT(compound);
         if (compound.contains("effect")) {
             setSpell(SpellRegistry.instance().createEffectFromNBT(compound.getCompound("effect")));
         }
@@ -215,6 +224,7 @@ public class MagicProjectileEntity extends ThrownItemEntity implements Magical,
     @Override
     public void writeCustomDataToTag(CompoundTag compound) {
         super.writeCustomDataToTag(compound);
+        physics.toNBT(compound);
 
         if (hasSpell()) {
             compound.put("effect", SpellRegistry.toNBT(getSpell(true)));

src/main/resources/assets/unicopia/particles/rainboom_trail.json

@@ -0,0 +1,2 @@
+{
+}

src/main/resources/data/unicopia/tags/blocks/fragile.json

@@ -0,0 +1,41 @@
+{
+  "replace": false,
+  "values": [
+    "minecraft:glass",
+    "minecraft:glass_pane",
+    "minecraft:white_stained_glass",
+    "minecraft:orange_stained_glass",
+    "minecraft:magenta_stained_glass",
+    "minecraft:light_blue_stained_glass",
+    "minecraft:yellow_stained_glass",
+    "minecraft:lime_stained_glass",
+    "minecraft:pink_stained_glass",
+    "minecraft:gray_stained_glass",
+    "minecraft:light_gray_stained_glass",
+    "minecraft:cyan_stained_glass",
+    "minecraft:purple_stained_glass",
+    "minecraft:blue_stained_glass",
+    "minecraft:brown_stained_glass",
+    "minecraft:green_stained_glass",
+    "minecraft:red_stained_glass",
+    "minecraft:black_stained_glass",
+    "minecraft:white_stained_glass_pane",
+    "minecraft:orange_stained_glass_pane",
+    "minecraft:magenta_stained_glass_pane",
+    "minecraft:light_blue_stained_glass_pane",
+    "minecraft:yellow_stained_glass_pane",
+    "minecraft:lime_stained_glass_pane",
+    "minecraft:pink_stained_glass_pane",
+    "minecraft:gray_stained_glass_pane",
+    "minecraft:light_gray_stained_glass_pane",
+    "minecraft:cyan_stained_glass_pane",
+    "minecraft:purple_stained_glass_pane",
+    "minecraft:blue_stained_glass_pane",
+    "minecraft:brown_stained_glass_pane",
+    "minecraft:green_stained_glass_pane",
+    "minecraft:red_stained_glass_pane",
+    "minecraft:black_stained_glass_pane",
+    "minecraft:vine",
+    "minecraft:lily_pad"
+  ]
+}