Use a single implementation for converting blocks

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

@@ -17,7 +17,6 @@ import com.minelittlepony.unicopia.util.shape.Sphere;
 import net.minecraft.block.Block;
 import net.minecraft.block.BlockState;
 import net.minecraft.block.Blocks;
-import net.minecraft.block.Material;
 import net.minecraft.block.RedstoneWireBlock;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.ItemEntity;
@@ -76,10 +75,9 @@ public class FireSpell extends AbstractSpell implements Thrown, Attached {
 
     protected boolean applyBlocks(World world, BlockPos pos) {
         BlockState state = world.getBlockState(pos);
-        Block id = state.getBlock();
 
-        if (id != Blocks.AIR) {
+        if (!state.isAir()) {
-            if (id == Blocks.NETHERRACK) {
+            if (state.isOf(Blocks.NETHERRACK)) {
                 if (world.isAir(pos.up())) {
 
                     if (world.random.nextInt(300) == 0) {
@@ -88,7 +86,7 @@ public class FireSpell extends AbstractSpell implements Thrown, Attached {
 
                     return true;
                 }
-            } else if (id == Blocks.REDSTONE_WIRE) {
+            } else if (state.isOf(Blocks.REDSTONE_WIRE)) {
                 int power = world.random.nextInt(5) == 3 ? 15 : 3;
 
                 sendPower(world, pos, power, 3, 0);
@@ -102,21 +100,15 @@ public class FireSpell extends AbstractSpell implements Thrown, Attached {
                     return true;
                 }
             } else if (state.isIn(BlockTags.LEAVES)) {
-                if (world.getBlockState(pos.up()).getMaterial() == Material.AIR) {
+                if (world.isAir(pos.up())) {
                     world.setBlockState(pos.up(), Blocks.FIRE.getDefaultState());
 
                     playEffect(world, pos);
                     return true;
                 }
-            } else {
+            } else if (StateMaps.FIRE_AFFECTED.convert(world, pos)) {
-                BlockState newState = StateMaps.FIRE_AFFECTED.getConverted(world, state);
+                playEffect(world, pos);
-
+                return true;
-                if (!state.equals(newState)) {
-                    world.setBlockState(pos, newState, 3);
-
-                    playEffect(world, pos);
-                    return true;
-                }
             }
         }
 

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

@@ -4,6 +4,7 @@ import com.minelittlepony.unicopia.ability.magic.Attached;
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.Thrown;
 import com.minelittlepony.unicopia.block.state.StateMaps;
+import com.minelittlepony.unicopia.particle.ParticleUtils;
 import com.minelittlepony.unicopia.util.MagicalDamageSource;
 import com.minelittlepony.unicopia.util.PosHelper;
 import com.minelittlepony.unicopia.util.VecHelper;
@@ -43,7 +44,14 @@ public class IceSpell extends AbstractSpell implements Thrown, Attached {
         LivingEntity owner = source.getMaster();
 
         PosHelper.getAllInRegionMutable(source.getOrigin(), effect_range)
-            .forEach(i -> applyBlockSingle(owner, source.getWorld(), i));
+            .forEach(i -> {
+                if (applyBlockSingle(owner, source.getWorld(), i)) {
+                    ParticleUtils.spawnParticle(ParticleTypes.SPLASH, source.getWorld(), new Vec3d(
+                            i.getX() + source.getWorld().random.nextFloat(),
+                            i.getY() + 1,
+                            i.getZ() + source.getWorld().random.nextFloat()), Vec3d.ZERO);
+                }
+            });
 
         return applyEntities(source.getMaster(), source.getWorld(), source.getOriginVector());
     }
@@ -65,25 +73,28 @@ public class IceSpell extends AbstractSpell implements Thrown, Attached {
         return true;
     }
 
-    private void applyBlockSingle(Entity owner, World world, BlockPos pos) {
+    private boolean applyBlockSingle(Entity owner, World world, BlockPos pos) {
         BlockState state = world.getBlockState(pos);
-        Block id = state.getBlock();
 
-        BlockState converted = StateMaps.ICE_AFFECTED.getConverted(world, state);
+        if (StateMaps.ICE_AFFECTED.convert(world, pos)) {
-
+            return true;
-        if (!state.equals(converted)) {
-            world.setBlockState(pos, converted, 3);
-        } else if (world.isTopSolid(pos, owner)
-                || (id == Blocks.SNOW)
-                || state.isIn(BlockTags.LEAVES)) {
-            incrementIce(world, pos.up());
-        } else if (state.getMaterial() == Material.ICE && world.random.nextInt(10) == 0) {
-            if (isSurroundedByIce(world, pos)) {
-                world.setBlockState(pos, Blocks.PACKED_ICE.getDefaultState());
-            }
         }
 
-        world.addParticle(ParticleTypes.SPLASH, pos.getX() + world.random.nextFloat(), pos.getY() + 1, pos.getZ() + world.random.nextFloat(), 0, 0, 0);
+        if (world.isTopSolid(pos, owner)
+                || state.isOf(Blocks.SNOW)
+                || state.isIn(BlockTags.LEAVES)) {
+            incrementIce(world, pos.up());
+            return true;
+        }
+
+        if (state.getMaterial() == Material.ICE
+                && world.random.nextInt(10) == 0
+                && isSurroundedByIce(world, pos)) {
+            world.setBlockState(pos, Blocks.PACKED_ICE.getDefaultState());
+            return true;
+        }
+
+        return false;
     }
 
     private static boolean isSurroundedByIce(World w, BlockPos pos) {

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

@@ -7,9 +7,6 @@ import com.minelittlepony.unicopia.util.MagicalDamageSource;
 import com.minelittlepony.unicopia.util.shape.Shape;
 import com.minelittlepony.unicopia.util.shape.Sphere;
 
-import net.minecraft.block.BlockState;
-import net.minecraft.block.DoorBlock;
-import net.minecraft.block.enums.DoubleBlockHalf;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.damage.DamageSource;
@@ -42,20 +39,7 @@ public class InfernoSpell extends FireSpell {
             for (int i = 0; i < radius; i++) {
                 BlockPos pos = new BlockPos(shape.computePoint(w.random).add(origin));
 
-                BlockState state = w.getBlockState(pos);
+                if (converter.convert(w, pos)) {
-                BlockState newState = converter.getConverted(w, state);
-
-                if (!state.equals(newState)) {
-
-                    if (newState.getBlock() instanceof DoorBlock) {
-                        boolean lower = newState.get(DoorBlock.HALF) == DoubleBlockHalf.LOWER;
-                        BlockPos other = lower ? pos.up() : pos.down();
-
-                        w.setBlockState(other, newState.with(DoorBlock.HALF, lower ? DoubleBlockHalf.UPPER : DoubleBlockHalf.LOWER), 16 | 2);
-                    }
-
-                    w.setBlockState(pos, newState, 16 | 2);
-
                     playEffect(w, pos);
                 }
             }

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

@@ -9,7 +9,6 @@ import com.minelittlepony.unicopia.projectile.MagicProjectileEntity;
 import com.minelittlepony.unicopia.util.PosHelper;
 import com.minelittlepony.unicopia.util.shape.Sphere;
 
-import net.minecraft.block.BlockState;
 import net.minecraft.particle.ParticleTypes;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.Vec3d;
@@ -25,12 +24,7 @@ public class ScorchSpell extends FireSpell {
 
         BlockPos pos = PosHelper.findSolidGroundAt(source.getWorld(), source.getOrigin(), source.getPhysics().getGravitySignum());
 
-        BlockState state = source.getWorld().getBlockState(pos);
+        if (StateMaps.FIRE_AFFECTED.convert(source.getWorld(), pos)) {
-
-        BlockState newState = StateMaps.FIRE_AFFECTED.getConverted(source.getWorld(), state);
-
-        if (!state.equals(newState)) {
-            source.getWorld().setBlockState(pos, newState, 3);
             source.spawnParticles(new Sphere(false, 1), 5, p -> {
                 source.addParticle(ParticleTypes.SMOKE, PosHelper.offset(p, pos), Vec3d.ZERO);
             });

src/main/java/com/minelittlepony/unicopia/block/state/BlockStateConverter.java

@@ -4,6 +4,9 @@ import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 import net.minecraft.block.BlockState;
+import net.minecraft.block.enums.DoubleBlockHalf;
+import net.minecraft.state.property.Properties;
+import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 
 public interface BlockStateConverter {
@@ -19,10 +22,47 @@ public interface BlockStateConverter {
     /**
      * Attempts to convert the given state based on the known mappings in this collection.
      *
+     * @param world        The world
      * @param state        State to convert
      *
-     * @return    The converted state if there is one, otherwise null
+     * @return    The converted state if there is one, otherwise the original state is returned
      */
     @Nonnull
     BlockState getConverted(World world, @Nonnull BlockState state);
+
+    /**
+     * Attempts to convert a block state at a position.
+     * Returns true if the block was changed.
+     *
+     */
+    default boolean convert(World world, BlockPos pos) {
+        BlockState state = world.getBlockState(pos);
+
+        if (!canConvert(state)) {
+            return false;
+        }
+
+        BlockState newState = getConverted(world, state);
+
+        if (state.equals(newState)) {
+            return false;
+        }
+
+        if (!newState.contains(Properties.DOUBLE_BLOCK_HALF)) {
+            world.setBlockState(pos, newState, 16 | 2);
+            return true;
+        }
+
+        boolean lower = newState.get(Properties.DOUBLE_BLOCK_HALF) == DoubleBlockHalf.LOWER;
+        BlockPos other = lower ? pos.up() : pos.down();
+
+        if (world.getBlockState(other).isOf(state.getBlock())) {
+            world.setBlockState(other, newState.with(Properties.DOUBLE_BLOCK_HALF, lower ? DoubleBlockHalf.UPPER : DoubleBlockHalf.LOWER), 16 | 2);
+            world.setBlockState(pos, newState, 16 | 2);
+
+            return true;
+        }
+
+        return false;
+    }
 }

src/main/java/com/minelittlepony/unicopia/entity/behaviour/SilverfishBehaviour.java

@@ -16,9 +16,7 @@ public class SilverfishBehaviour extends EntityBehaviour<SilverfishEntity> {
             BlockPos pos = entity.getBlockPos().down();
             BlockState state = entity.world.getBlockState(pos);
 
-            if (StateMaps.SILVERFISH_AFFECTED.canConvert(state)) {
+            if (StateMaps.SILVERFISH_AFFECTED.convert(entity.world, pos)) {
-
-                entity.world.setBlockState(pos, StateMaps.SILVERFISH_AFFECTED.getConverted(entity.world, state));
                 WorldEvent.play(WorldEvent.DESTROY_BLOCK, entity.world, pos, state);
             }
         }