added breeding tracking

src/main/java/carpet/helpers/ParticleDisplay.java

@@ -0,0 +1,73 @@
+package carpet.helpers;
+
+import com.mojang.brigadier.StringReader;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import net.minecraft.command.arguments.ParticleArgumentType;
+import net.minecraft.particle.ParticleEffect;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.server.world.ServerWorld;
+import net.minecraft.util.math.Vec3d;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class ParticleDisplay
+{
+    private static Map<String, ParticleEffect> particleCache = new HashMap<>();
+
+    private static ParticleEffect parseParticle(String name)
+    {
+        try
+        {
+            return ParticleArgumentType.readParameters(new StringReader(name));
+        }
+        catch (CommandSyntaxException e)
+        {
+            throw new RuntimeException("No such particle: "+name);
+        }
+    }
+    private static ParticleEffect getEffect(String name)
+    {
+        if (name == null) return null;
+        ParticleEffect res = particleCache.get(name);
+        if (res != null) return res;
+        particleCache.put(name, parseParticle(name));
+        return particleCache.get(name);
+    }
+
+    public static void drawParticleLine(ServerPlayerEntity player, Vec3d from, Vec3d to,String main)
+    {
+        drawParticleLine(player, from, to, main, null, 1, 0.0);
+    }
+
+    public static void drawParticleLine(ServerPlayerEntity player, Vec3d from, Vec3d to, String main, String accent, int count, double spread)
+    {
+        ParticleEffect accentParticle = getEffect(accent);
+        ParticleEffect mainParticle = getEffect(main);
+
+        if (accentParticle != null) ((ServerWorld)player.world).spawnParticles(
+                player,
+                accentParticle,
+                true,
+                to.x, to.y, to.z, count,
+                spread, spread, spread, 0.0);
+
+        double lineLengthSq = from.squaredDistanceTo(to);
+        if (lineLengthSq == 0) return;
+
+        Vec3d incvec = to.subtract(from).normalize();//    multiply(50/sqrt(lineLengthSq));
+        int pcount = 0;
+        for (Vec3d delta = new Vec3d(0.0,0.0,0.0);
+             delta.lengthSquared()<lineLengthSq;
+             delta = delta.add(incvec.multiply(player.world.random.nextFloat())))
+        {
+            ((ServerWorld)player.world).spawnParticles(
+                    player,
+                    mainParticle,
+                    true,
+                    delta.x+from.x, delta.y+from.y, delta.z+from.z, 1,
+                    0.0, 0.0, 0.0, 0.0);
+        }
+    }
+
+}