Block: introduce logic for face support types (#4886)

fixes #4856
fixes #458
fixes #4529
fixes #3299

Added API method Block::getSupportType(Facing) : SupportType
Added SupportType enum
fixes torch, lantern, door etc. placement on slabs and upside-down stairs

src/block/Air.php

@@ -23,16 +23,10 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
-use pocketmine\math\AxisAlignedBB;
-
 /**
  * Air block
  */
-class Air extends Transparent{
-
-	public function canBeFlowedInto() : bool{
-		return true;
-	}
+class Air extends Flowable{
 
 	public function canBeReplaced() : bool{
 		return true;
@@ -41,15 +35,4 @@ class Air extends Transparent{
 	public function canBePlaced() : bool{
 		return false;
 	}
-
-	public function isSolid() : bool{
-		return false;
-	}
-
-	/**
-	 * @return AxisAlignedBB[]
-	 */
-	protected function recalculateCollisionBoxes() : array{
-		return [];
-	}
 }

src/block/Anvil.php

@@ -28,6 +28,7 @@ use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\Fallable;
 use pocketmine\block\utils\FallableTrait;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -80,6 +81,10 @@ class Anvil extends Transparent implements Fallable{
 		return [AxisAlignedBB::one()->squash(Facing::axis(Facing::rotateY($this->facing, false)), 1 / 8)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onInteract(Item $item, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		if($player instanceof Player){
 			$player->setCurrentWindow(new AnvilInventory($this->position));

src/block/Bamboo.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\block\utils\SupportType;
 use pocketmine\event\block\StructureGrowEvent;
 use pocketmine\item\Bamboo as ItemBamboo;
 use pocketmine\item\Fertilizer;
@@ -100,6 +101,10 @@ class Bamboo extends Transparent{
 		return [AxisAlignedBB::one()->trim(Facing::SOUTH, $inset)->trim(Facing::EAST, $inset)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	private static function getOffsetSeed(int $x, int $y, int $z) : int{
 		$p1 = gmp_mul($z, 0x6ebfff5);
 		$p2 = gmp_mul($x, 0x2fc20f);

src/block/BaseBanner.php

@@ -27,6 +27,7 @@ use pocketmine\block\tile\Banner as TileBanner;
 use pocketmine\block\utils\BannerPatternLayer;
 use pocketmine\block\utils\ColoredTrait;
 use pocketmine\block\utils\DyeColor;
+use pocketmine\block\utils\SupportType;
 use pocketmine\data\bedrock\DyeColorIdMap;
 use pocketmine\item\Banner as ItemBanner;
 use pocketmine\item\Item;
@@ -107,6 +108,10 @@ abstract class BaseBanner extends Transparent{
 		return [];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		if($item instanceof ItemBanner){
 			$this->color = $item->getColor();

src/block/BaseCoral.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\CoralType;
 use pocketmine\block\utils\CoralTypeTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 
 abstract class BaseCoral extends Transparent{
@@ -65,4 +66,8 @@ abstract class BaseCoral extends Transparent{
 	public function isSolid() : bool{ return false; }
 
 	protected function recalculateCollisionBoxes() : array{ return []; }
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/BaseRail.php

@@ -38,7 +38,7 @@ use function in_array;
 abstract class BaseRail extends Flowable{
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$blockReplace->getSide(Facing::DOWN)->isTransparent()){
+		if($blockReplace->getSide(Facing::DOWN)->getSupportType(Facing::UP)->hasEdgeSupport()){
 			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
 		}
 
@@ -220,11 +220,11 @@ abstract class BaseRail extends Flowable{
 	}
 
 	public function onNearbyBlockChange() : void{
-		if($this->getSide(Facing::DOWN)->isTransparent()){
+		if(!$this->getSide(Facing::DOWN)->getSupportType(Facing::UP)->hasEdgeSupport()){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}else{
 			foreach($this->getCurrentShapeConnections() as $connection){
-				if(($connection & RailConnectionInfo::FLAG_ASCEND) !== 0 && $this->getSide($connection & ~RailConnectionInfo::FLAG_ASCEND)->isTransparent()){
+				if(($connection & RailConnectionInfo::FLAG_ASCEND) !== 0 && !$this->getSide($connection & ~RailConnectionInfo::FLAG_ASCEND)->getSupportType(Facing::UP)->hasEdgeSupport()){
 					$this->position->getWorld()->useBreakOn($this->position);
 					break;
 				}

src/block/BaseSign.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\tile\Sign as TileSign;
 use pocketmine\block\utils\SignText;
+use pocketmine\block\utils\SupportType;
 use pocketmine\event\block\SignChangeEvent;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
@@ -77,6 +78,10 @@ abstract class BaseSign extends Transparent{
 		return [];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	abstract protected function getSupportingFace() : int;
 
 	public function onNearbyBlockChange() : void{

src/block/Bed.php

@@ -28,6 +28,7 @@ use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\ColoredTrait;
 use pocketmine\block\utils\DyeColor;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\data\bedrock\DyeColorIdMap;
 use pocketmine\entity\Entity;
 use pocketmine\entity\Living;
@@ -94,6 +95,10 @@ class Bed extends Transparent{
 		return [AxisAlignedBB::one()->trim(Facing::UP, 7 / 16)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function isHeadPart() : bool{
 		return $this->head;
 	}
@@ -181,12 +186,11 @@ class Bed extends Transparent{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		$down = $this->getSide(Facing::DOWN);
-		if(!$down->isTransparent()){
+		if($this->canBeSupportedBy($this->getSide(Facing::DOWN))){
 			$this->facing = $player !== null ? $player->getHorizontalFacing() : Facing::NORTH;
 
 			$next = $this->getSide($this->getOtherHalfSide());
-			if($next->canBeReplaced() && !$next->getSide(Facing::DOWN)->isTransparent()){
+			if($next->canBeReplaced() && $this->canBeSupportedBy($next->getSide(Facing::DOWN))){
 				$nextState = clone $this;
 				$nextState->head = true;
 				$tx->addBlock($blockReplace->position, $this)->addBlock($next->position, $nextState);
@@ -216,4 +220,8 @@ class Bed extends Transparent{
 
 		return parent::getAffectedBlocks();
 	}
+
+	private function canBeSupportedBy(Block $block) : bool{
+		return !$block->getSupportType(Facing::UP)->equals(SupportType::NONE());
+	}
 }

src/block/Bell.php

@@ -28,6 +28,7 @@ use pocketmine\block\utils\BellAttachmentType;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
 use pocketmine\block\utils\InvalidBlockStateException;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -101,6 +102,10 @@ final class Bell extends Transparent{
 		];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function getAttachmentType() : BellAttachmentType{ return $this->attachmentType; }
 
 	/** @return $this */

src/block/Block.php

@@ -29,6 +29,7 @@ namespace pocketmine\block;
 use pocketmine\block\tile\Spawnable;
 use pocketmine\block\tile\Tile;
 use pocketmine\block\utils\InvalidBlockStateException;
+use pocketmine\block\utils\SupportType;
 use pocketmine\entity\Entity;
 use pocketmine\item\enchantment\VanillaEnchantments;
 use pocketmine\item\Item;
@@ -610,6 +611,10 @@ class Block{
 		return [AxisAlignedBB::one()];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::FULL();
+	}
+
 	public function isFullCube() : bool{
 		$bb = $this->getCollisionBoxes();
 

src/block/BrewingStand.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\tile\BrewingStand as TileBrewingStand;
 use pocketmine\block\utils\BrewingStandSlot;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\Axis;
 use pocketmine\math\AxisAlignedBB;
@@ -83,6 +84,10 @@ class BrewingStand extends Transparent{
 		];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function hasSlot(BrewingStandSlot $slot) : bool{
 		return array_key_exists($slot->id(), $this->slots);
 	}

src/block/Button.php

@@ -61,9 +61,11 @@ abstract class Button extends Flowable{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		//TODO: check valid target block
-		$this->facing = $face;
-		return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
+		if($this->canBeSupportedBy($blockClicked, $face)){
+			$this->facing = $face;
+			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
+		}
+		return false;
 	}
 
 	abstract protected function getActivationTime() : int;
@@ -86,4 +88,14 @@ abstract class Button extends Flowable{
 			$this->position->getWorld()->addSound($this->position->add(0.5, 0.5, 0.5), new RedstonePowerOffSound());
 		}
 	}
+
+	public function onNearbyBlockChange() : void{
+		if(!$this->canBeSupportedBy($this->getSide(Facing::opposite($this->facing)), $this->facing)){
+			$this->position->getWorld()->useBreakOn($this->position);
+		}
+	}
+
+	private function canBeSupportedBy(Block $support, int $face) : bool{
+		return $support->getSupportType($face)->hasCenterSupport();
+	}
 }

src/block/Cactus.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\block\utils\SupportType;
 use pocketmine\entity\Entity;
 use pocketmine\event\block\BlockGrowEvent;
 use pocketmine\event\entity\EntityDamageByBlockEvent;
@@ -75,6 +76,10 @@ class Cactus extends Transparent{
 		return [AxisAlignedBB::one()->contract($shrinkSize, 0, $shrinkSize)->trim(Facing::UP, $shrinkSize)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onEntityInside(Entity $entity) : bool{
 		$ev = new EntityDamageByBlockEvent($this, $entity, EntityDamageEvent::CAUSE_CONTACT, 1);
 		$entity->attack($ev);

src/block/Cake.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\block\utils\SupportType;
 use pocketmine\entity\effect\EffectInstance;
 use pocketmine\entity\FoodSource;
 use pocketmine\entity\Living;
@@ -63,6 +64,10 @@ class Cake extends Transparent implements FoodSource{
 		];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function getBites() : int{ return $this->bites; }
 
 	/** @return $this */

src/block/Chest.php

@@ -26,6 +26,7 @@ namespace pocketmine\block;
 use pocketmine\block\tile\Chest as TileChest;
 use pocketmine\block\utils\FacesOppositePlacingPlayerTrait;
 use pocketmine\block\utils\NormalHorizontalFacingInMetadataTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\event\block\ChestPairEvent;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
@@ -45,6 +46,10 @@ class Chest extends Transparent{
 		return [AxisAlignedBB::one()->contract(0.025, 0, 0.025)->trim(Facing::UP, 0.05)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onPostPlace() : void{
 		$tile = $this->position->getWorld()->getTile($this->position);
 		if($tile instanceof TileChest){

src/block/CocoaBlock.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\block\utils\TreeType;
 use pocketmine\event\block\BlockGrowEvent;
 use pocketmine\item\Fertilizer;
@@ -83,6 +84,10 @@ class CocoaBlock extends Transparent{
 		];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	private function canAttachTo(Block $block) : bool{
 		return $block instanceof Wood && $block->getTreeType()->equals(TreeType::JUNGLE());
 	}

src/block/Coral.php

@@ -26,6 +26,7 @@ namespace pocketmine\block;
 use pocketmine\block\utils\InvalidBlockStateException;
 use pocketmine\data\bedrock\CoralTypeIdMap;
 use pocketmine\item\Item;
+use pocketmine\math\Facing;
 use pocketmine\math\Vector3;
 use pocketmine\player\Player;
 use pocketmine\world\BlockTransaction;
@@ -65,7 +66,7 @@ final class Coral extends BaseCoral{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$tx->fetchBlock($blockReplace->getPosition()->down())->isSolid()){
+		if(!$this->canBeSupportedBy($tx->fetchBlock($blockReplace->getPosition()->down()))){
 			return false;
 		}
 		return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
@@ -73,10 +74,14 @@ final class Coral extends BaseCoral{
 
 	public function onNearbyBlockChange() : void{
 		$world = $this->position->getWorld();
-		if(!$world->getBlock($this->position->down())->isSolid()){
+		if(!$this->canBeSupportedBy($world->getBlock($this->position->down()))){
 			$world->useBreakOn($this->position);
 		}else{
 			parent::onNearbyBlockChange();
 		}
 	}
+
+	private function canBeSupportedBy(Block $block) : bool{
+		return $block->getSupportType(Facing::UP)->hasCenterSupport();
+	}
 }

src/block/DaylightSensor.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\AnalogRedstoneSignalEmitterTrait;
 use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -87,6 +88,10 @@ class DaylightSensor extends Transparent{
 		return [AxisAlignedBB::one()->trim(Facing::UP, 10 / 16)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onInteract(Item $item, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		$this->inverted = !$this->inverted;
 		$this->signalStrength = $this->recalculateSignalStrength();

src/block/Door.php

@@ -26,6 +26,7 @@ namespace pocketmine\block;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
 use pocketmine\block\utils\PoweredByRedstoneTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -119,8 +120,12 @@ class Door extends Transparent{
 		return [AxisAlignedBB::one()->trim($this->open ? Facing::rotateY($this->facing, !$this->hingeRight) : $this->facing, 327 / 400)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onNearbyBlockChange() : void{
-		if($this->getSide(Facing::DOWN)->getId() === BlockLegacyIds::AIR){ //Replace with common break method
+		if(!$this->canBeSupportedBy($this->getSide(Facing::DOWN)) && !$this->getSide(Facing::DOWN) instanceof Door){ //Replace with common break method
 			$this->position->getWorld()->useBreakOn($this->position); //this will delete both halves if they exist
 		}
 	}
@@ -129,7 +134,7 @@ class Door extends Transparent{
 		if($face === Facing::UP){
 			$blockUp = $this->getSide(Facing::UP);
 			$blockDown = $this->getSide(Facing::DOWN);
-			if(!$blockUp->canBeReplaced() || $blockDown->isTransparent()){
+			if(!$blockUp->canBeReplaced() || !$this->canBeSupportedBy($blockDown)){
 				return false;
 			}
 
@@ -184,4 +189,8 @@ class Door extends Transparent{
 		}
 		return parent::getAffectedBlocks();
 	}
+
+	private function canBeSupportedBy(Block $block) : bool{
+		return $block->getSupportType(Facing::UP)->hasEdgeSupport();
+	}
 }

src/block/DragonEgg.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\Fallable;
 use pocketmine\block\utils\FallableTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\event\block\BlockTeleportEvent;
 use pocketmine\item\Item;
 use pocketmine\math\Vector3;
@@ -82,4 +83,8 @@ class DragonEgg extends Transparent implements Fallable{
 			}
 		}
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/EnchantingTable.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\inventory\EnchantInventory;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -39,6 +40,10 @@ class EnchantingTable extends Transparent{
 		return [AxisAlignedBB::one()->trim(Facing::UP, 0.25)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onInteract(Item $item, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		if($player instanceof Player){
 			//TODO lock

src/block/EnderChest.php

@@ -27,6 +27,7 @@ use pocketmine\block\inventory\EnderChestInventory;
 use pocketmine\block\tile\EnderChest as TileEnderChest;
 use pocketmine\block\utils\FacesOppositePlacingPlayerTrait;
 use pocketmine\block\utils\NormalHorizontalFacingInMetadataTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -49,6 +50,10 @@ class EnderChest extends Transparent{
 		return [AxisAlignedBB::one()->contract(0.025, 0, 0.025)->trim(Facing::UP, 0.05)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function onInteract(Item $item, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		if($player instanceof Player){
 			$enderChest = $this->position->getWorld()->getTile($this->position);

src/block/Fence.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\math\Axis;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -93,4 +94,8 @@ class Fence extends Transparent{
 
 		return $bbs;
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return Facing::axis($facing) === Axis::Y ? SupportType::CENTER() : SupportType::NONE();
+	}
 }

src/block/FenceGate.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -78,6 +79,10 @@ class FenceGate extends Transparent{
 		return $this->open ? [] : [AxisAlignedBB::one()->extend(Facing::UP, 0.5)->squash(Facing::axis($this->facing), 6 / 16)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	private function checkInWall() : bool{
 		return (
 			$this->getSide(Facing::rotateY($this->facing, false)) instanceof Wall ||

src/block/FloorCoralFan.php

@@ -29,6 +29,7 @@ use pocketmine\item\Item;
 use pocketmine\item\ItemFactory;
 use pocketmine\item\ItemIds;
 use pocketmine\math\Axis;
+use pocketmine\math\Facing;
 use pocketmine\math\Vector3;
 use pocketmine\player\Player;
 use pocketmine\world\BlockTransaction;
@@ -93,7 +94,7 @@ final class FloorCoralFan extends BaseCoral{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$tx->fetchBlock($blockReplace->getPosition()->down())->isSolid()){
+		if(!$this->canBeSupportedBy($tx->fetchBlock($blockReplace->getPosition()->down()))){
 			return false;
 		}
 		if($player !== null){
@@ -112,11 +113,15 @@ final class FloorCoralFan extends BaseCoral{
 
 	public function onNearbyBlockChange() : void{
 		$world = $this->position->getWorld();
-		if(!$world->getBlock($this->position->down())->isSolid()){
+		if(!$this->canBeSupportedBy($world->getBlock($this->position->down()))){
 			$world->useBreakOn($this->position);
 		}else{
 			parent::onNearbyBlockChange();
 		}
 	}
 
+	private function canBeSupportedBy(Block $block) : bool{
+		return $block->getSupportType(Facing::UP)->hasCenterSupport();
+	}
+
 }

src/block/Flowable.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\math\AxisAlignedBB;
 
 abstract class Flowable extends Transparent{
@@ -41,4 +42,8 @@ abstract class Flowable extends Transparent{
 	protected function recalculateCollisionBoxes() : array{
 		return [];
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/FlowerPot.php

@@ -104,7 +104,7 @@ class FlowerPot extends Flowable{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if($this->getSide(Facing::DOWN)->isTransparent()){
+		if(!$this->canBeSupportedBy($this->getSide(Facing::DOWN))){
 			return false;
 		}
 
@@ -112,11 +112,15 @@ class FlowerPot extends Flowable{
 	}
 
 	public function onNearbyBlockChange() : void{
-		if($this->getSide(Facing::DOWN)->isTransparent()){
+		if(!$this->canBeSupportedBy($this->getSide(Facing::DOWN))){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
 
+	private function canBeSupportedBy(Block $block) : bool{
+		return $block->getSupportType(Facing::UP)->hasCenterSupport();
+	}
+
 	public function onInteract(Item $item, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		$plant = $item->getBlock();
 		if($this->plant !== null){

src/block/Hopper.php

@@ -27,6 +27,7 @@ use pocketmine\block\tile\Hopper as TileHopper;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\InvalidBlockStateException;
 use pocketmine\block\utils\PoweredByRedstoneTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -78,6 +79,14 @@ class Hopper extends Transparent{
 		return $result;
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return match($facing){
+			Facing::UP => SupportType::FULL(),
+			Facing::DOWN => $this->facing === Facing::DOWN ? SupportType::CENTER() : SupportType::NONE(),
+			default => SupportType::NONE()
+		};
+	}
+
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		$this->facing = $face === Facing::DOWN ? Facing::DOWN : Facing::opposite($face);
 

src/block/Ladder.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\utils\NormalHorizontalFacingInMetadataTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\entity\Entity;
 use pocketmine\entity\Living;
 use pocketmine\item\Item;
@@ -64,8 +65,12 @@ class Ladder extends Transparent{
 		return [AxisAlignedBB::one()->trim($this->facing, 13 / 16)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$blockClicked->isTransparent() && Facing::axis($face) !== Axis::Y){
+		if($this->canBeSupportedBy($blockClicked, $face) && Facing::axis($face) !== Axis::Y){
 			$this->facing = $face;
 			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
 		}
@@ -74,8 +79,12 @@ class Ladder extends Transparent{
 	}
 
 	public function onNearbyBlockChange() : void{
-		if(!$this->getSide(Facing::opposite($this->facing))->isSolid()){ //Replace with common break method
+		if(!$this->canBeSupportedBy($this->getSide(Facing::opposite($this->facing)), $this->facing)){ //Replace with common break method
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
+
+	private function canBeSupportedBy(Block $block, int $face) : bool{
+		return $block->getSupportType($face)->equals(SupportType::FULL());
+	}
 }

src/block/Lantern.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\Axis;
 use pocketmine\math\AxisAlignedBB;
@@ -72,22 +73,27 @@ class Lantern extends Transparent{
 		];
 	}
 
-	protected function canAttachTo(Block $b) : bool{
-		return !$b->isTransparent();
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$this->canAttachTo($this->position->getWorld()->getBlock($blockReplace->getPosition()->up())) && !$this->canAttachTo($this->position->getWorld()->getBlock($blockReplace->getPosition()->down()))){
+		if(!$this->canBeSupportedBy($blockReplace->getSide(Facing::UP), Facing::DOWN) && !$this->canBeSupportedBy($blockReplace->getSide(Facing::DOWN), Facing::UP)){
 			return false;
 		}
 
-		$this->hanging = ($face === Facing::DOWN || !$this->canAttachTo($this->position->getWorld()->getBlock($blockReplace->getPosition()->down())));
+		$this->hanging = ($face === Facing::DOWN || !$this->canBeSupportedBy($this->position->getWorld()->getBlock($blockReplace->getPosition()->down()), Facing::UP));
 		return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
 	}
 
 	public function onNearbyBlockChange() : void{
-		if(!$this->canAttachTo($this->position->getWorld()->getBlock($this->hanging ? $this->position->up() : $this->position->down()))){
+		$face = $this->hanging ? Facing::UP : Facing::DOWN;
+		if(!$this->canBeSupportedBy($this->getSide($face), Facing::opposite($face))){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
+
+	private function canBeSupportedBy(Block $block, int $face) : bool{
+		return $block->getSupportType($face)->hasCenterSupport();
+	}
 }

src/block/Leaves.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\block\utils\TreeType;
 use pocketmine\event\block\LeavesDecayEvent;
 use pocketmine\item\Item;
@@ -166,4 +167,8 @@ class Leaves extends Transparent{
 	public function getFlammability() : int{
 		return 60;
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/Lectern.php

@@ -27,6 +27,7 @@ use pocketmine\block\tile\Lectern as TileLectern;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\FacesOppositePlacingPlayerTrait;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\item\WritableBookBase;
 use pocketmine\math\AxisAlignedBB;
@@ -92,6 +93,10 @@ class Lectern extends Transparent{
 		return [AxisAlignedBB::one()->trim(Facing::UP, 0.1)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function isProducingSignal() : bool{ return $this->producingSignal; }
 
 	/** @return $this */

src/block/Lever.php

@@ -96,7 +96,7 @@ class Lever extends Flowable{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$blockClicked->isSolid()){
+		if(!$this->canBeSupportedBy($blockClicked, $face)){
 			return false;
 		}
 
@@ -120,7 +120,8 @@ class Lever extends Flowable{
 	}
 
 	public function onNearbyBlockChange() : void{
-		if(!$this->getSide(Facing::opposite($this->facing->getFacing()))->isSolid()){
+		$facing = $this->facing->getFacing();
+		if(!$this->canBeSupportedBy($this->getSide(Facing::opposite($facing)), $facing)){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
@@ -135,5 +136,9 @@ class Lever extends Flowable{
 		return true;
 	}
 
+	private function canBeSupportedBy(Block $block, int $face) : bool{
+		return $block->getSupportType($face)->hasCenterSupport();
+	}
+
 	//TODO
 }

src/block/Liquid.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\MinimumCostFlowCalculator;
+use pocketmine\block\utils\SupportType;
 use pocketmine\entity\Entity;
 use pocketmine\event\block\BlockFormEvent;
 use pocketmine\event\block\BlockSpreadEvent;
@@ -114,6 +115,10 @@ abstract class Liquid extends Transparent{
 		return [];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function getDropsForCompatibleTool(Item $item) : array{
 		return [];
 	}

src/block/MonsterSpawner.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use function mt_rand;
 
@@ -39,4 +40,8 @@ class MonsterSpawner extends Transparent{
 	public function onScheduledUpdate() : void{
 		//TODO
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/NetherPortal.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\entity\Entity;
 use pocketmine\item\Item;
 use pocketmine\math\Axis;
@@ -75,6 +76,10 @@ class NetherPortal extends Transparent{
 		return [];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function getDrops(Item $item) : array{
 		return [];
 	}

src/block/PressurePlate.php

@@ -23,6 +23,13 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
+use pocketmine\item\Item;
+use pocketmine\math\Facing;
+use pocketmine\math\Vector3;
+use pocketmine\player\Player;
+use pocketmine\world\BlockTransaction;
+
 abstract class PressurePlate extends Transparent{
 
 	public function isSolid() : bool{
@@ -33,5 +40,20 @@ abstract class PressurePlate extends Transparent{
 		return [];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
+	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
+		if($this->canBeSupportedBy($blockClicked)){
+			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
+		}
+		return false;
+	}
+
+	private function canBeSupportedBy(Block $block) : bool{
+		return !$block->getSupportType(Facing::UP)->equals(SupportType::NONE());
+	}
+
 	//TODO
 }

src/block/RedstoneComparator.php

@@ -28,6 +28,7 @@ use pocketmine\block\utils\AnalogRedstoneSignalEmitterTrait;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
 use pocketmine\block\utils\PoweredByRedstoneTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -103,7 +104,7 @@ class RedstoneComparator extends Flowable{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$blockReplace->getSide(Facing::DOWN)->isTransparent()){
+		if($this->canBeSupportedBy($blockReplace->getSide(Facing::DOWN))){
 			if($player !== null){
 				$this->facing = Facing::opposite($player->getHorizontalFacing());
 			}
@@ -120,10 +121,14 @@ class RedstoneComparator extends Flowable{
 	}
 
 	public function onNearbyBlockChange() : void{
-		if($this->getSide(Facing::DOWN)->isTransparent()){
+		if(!$this->canBeSupportedBy($this->getSide(Facing::DOWN))){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
 
+	private function canBeSupportedBy(Block $block) : bool{
+		return !$block->getSupportType(Facing::UP)->equals(SupportType::NONE());
+	}
+
 	//TODO: redstone functionality
 }

src/block/RedstoneRepeater.php

@@ -26,6 +26,7 @@ namespace pocketmine\block;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
 use pocketmine\block\utils\PoweredByRedstoneTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -86,7 +87,7 @@ class RedstoneRepeater extends Flowable{
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if(!$blockReplace->getSide(Facing::DOWN)->isTransparent()){
+		if($this->canBeSupportedBy($blockReplace->getSide(Facing::DOWN))){
 			if($player !== null){
 				$this->facing = Facing::opposite($player->getHorizontalFacing());
 			}
@@ -106,10 +107,14 @@ class RedstoneRepeater extends Flowable{
 	}
 
 	public function onNearbyBlockChange() : void{
-		if($this->getSide(Facing::DOWN)->isTransparent()){
+		if(!$this->canBeSupportedBy($this->getSide(Facing::DOWN))){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
 
+	private function canBeSupportedBy(Block $block) : bool{
+		return !$block->getSupportType(Facing::UP)->equals(SupportType::NONE());
+	}
+
 	//TODO: redstone functionality
 }

src/block/RedstoneWire.php

@@ -25,10 +25,22 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\AnalogRedstoneSignalEmitterTrait;
 use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\item\Item;
+use pocketmine\math\Facing;
+use pocketmine\math\Vector3;
+use pocketmine\player\Player;
+use pocketmine\world\BlockTransaction;
 
 class RedstoneWire extends Flowable{
 	use AnalogRedstoneSignalEmitterTrait;
 
+	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
+		if($this->canBeSupportedBy($this->getSide(Facing::DOWN))){
+			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
+		}
+		return false;
+	}
+
 	public function readStateFromData(int $id, int $stateMeta) : void{
 		$this->signalStrength = BlockDataSerializer::readBoundedInt("signalStrength", $stateMeta, 0, 15);
 	}
@@ -45,4 +57,14 @@ class RedstoneWire extends Flowable{
 		parent::readStateFromWorld();
 		//TODO: check connections to nearby redstone components
 	}
+
+	public function onNearbyBlockChange() : void{
+		if(!$this->canBeSupportedBy($this->getSide(Facing::DOWN))){
+			$this->position->getWorld()->useBreakOn($this->position);
+		}
+	}
+
+	private function canBeSupportedBy(Block $block) : bool{
+		return $block->getSupportType(Facing::UP)->hasCenterSupport();
+	}
 }

src/block/SeaPickle.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Vector3;
@@ -83,6 +84,10 @@ class SeaPickle extends Transparent{
 		return [];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function canBePlacedAt(Block $blockReplace, Vector3 $clickVector, int $face, bool $isClickedBlock) : bool{
 		//TODO: proper placement logic (needs a supporting face below)
 		return ($blockReplace instanceof SeaPickle && $blockReplace->count < self::MAX_COUNT) || parent::canBePlacedAt($blockReplace, $clickVector, $face, $isClickedBlock);

src/block/Slab.php

@@ -24,6 +24,7 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\utils\SlabType;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -125,6 +126,15 @@ class Slab extends Transparent{
 		return [AxisAlignedBB::one()->trim($this->slabType->equals(SlabType::TOP()) ? Facing::DOWN : Facing::UP, 0.5)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		if($this->slabType->equals(SlabType::DOUBLE())){
+			return SupportType::FULL();
+		}elseif(($facing === Facing::UP && $this->slabType->equals(SlabType::TOP())) || ($facing === Facing::DOWN && $this->slabType->equals(SlabType::BOTTOM()))){
+			return SupportType::FULL();
+		}
+		return SupportType::NONE();
+	}
+
 	public function getDropsForCompatibleTool(Item $item) : array{
 		return [$this->asItem()->setCount($this->slabType->equals(SlabType::DOUBLE()) ? 2 : 1)];
 	}

src/block/SnowLayer.php

@@ -26,6 +26,7 @@ namespace pocketmine\block;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\Fallable;
 use pocketmine\block\utils\FallableTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\event\block\BlockMeltEvent;
 use pocketmine\item\Item;
 use pocketmine\item\VanillaItems;
@@ -80,8 +81,15 @@ class SnowLayer extends Flowable implements Fallable{
 		return [AxisAlignedBB::one()->trim(Facing::UP, $this->layers >= 4 ? 0.5 : 1)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		if(!$this->canBeReplaced()){
+			return SupportType::FULL();
+		}
+		return SupportType::NONE();
+	}
+
 	private function canBeSupportedBy(Block $b) : bool{
-		return $b->isSolid() || ($b instanceof SnowLayer && $b->isSameType($this) && $b->layers === self::MAX_LAYERS);
+		return $b->getSupportType(Facing::UP)->equals(SupportType::FULL());
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{

src/block/Stair.php

@@ -26,7 +26,9 @@ namespace pocketmine\block;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
 use pocketmine\block\utils\StairShape;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
+use pocketmine\math\Axis;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
 use pocketmine\math\Vector3;
@@ -111,6 +113,19 @@ class Stair extends Transparent{
 		return $bbs;
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		if(
+			$facing === Facing::UP && $this->isUpsideDown() ||
+			$facing === Facing::DOWN && !$this->isUpsideDown() ||
+			($facing === $this->facing && !$this->shape->equals(StairShape::OUTER_LEFT()) && !$this->shape->equals(StairShape::OUTER_RIGHT())) ||
+			($facing === Facing::rotate($this->facing, Axis::Y, false) && $this->shape->equals(StairShape::INNER_LEFT())) ||
+			($facing === Facing::rotate($this->facing, Axis::Y, true) && $this->shape->equals(StairShape::INNER_RIGHT()))
+		){
+			return SupportType::FULL();
+		}
+		return SupportType::NONE();
+	}
+
 	private function getPossibleCornerFacing(bool $oppositeFacing) : ?int{
 		$side = $this->getSide($oppositeFacing ? Facing::opposite($this->facing) : $this->facing);
 		return (

src/block/Stonecutter.php

@@ -27,6 +27,7 @@ use pocketmine\block\inventory\StonecutterInventory;
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\FacesOppositePlacingPlayerTrait;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -59,4 +60,8 @@ class Stonecutter extends Transparent{
 	protected function recalculateCollisionBoxes() : array{
 		return [AxisAlignedBB::one()->trim(Facing::UP, 7 / 16)];
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/Thin.php

@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
 use pocketmine\math\Axis;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -82,4 +83,8 @@ class Thin extends Transparent{
 
 		return $bbs;
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
 }

src/block/Torch.php

@@ -24,7 +24,9 @@ declare(strict_types=1);
 namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
+use pocketmine\math\Axis;
 use pocketmine\math\Facing;
 use pocketmine\math\Vector3;
 use pocketmine\player\Player;
@@ -66,16 +68,16 @@ class Torch extends Flowable{
 		$below = $this->getSide(Facing::DOWN);
 		$face = Facing::opposite($this->facing);
 
-		if($this->getSide($face)->isTransparent() && !($face === Facing::DOWN && ($below->getId() === BlockLegacyIds::FENCE || $below->getId() === BlockLegacyIds::COBBLESTONE_WALL))){
+		if(!$this->canBeSupportedBy($this->getSide($face), $this->facing)){
 			$this->position->getWorld()->useBreakOn($this->position);
 		}
 	}
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
-		if($blockClicked->canBeReplaced() && !$blockClicked->getSide(Facing::DOWN)->isTransparent()){
+		if($blockClicked->canBeReplaced() && $this->canBeSupportedBy($blockClicked->getSide(Facing::DOWN), Facing::UP)){
 			$this->facing = Facing::UP;
 			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
-		}elseif($face !== Facing::DOWN && (!$blockClicked->isTransparent() || ($face === Facing::UP && ($blockClicked->getId() === BlockLegacyIds::FENCE || $blockClicked->getId() === BlockLegacyIds::COBBLESTONE_WALL)))){
+		}elseif($face !== Facing::DOWN && $this->canBeSupportedBy($blockClicked, $face)){
 			$this->facing = $face;
 			return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
 		}else{
@@ -87,7 +89,7 @@ class Torch extends Flowable{
 				Facing::DOWN
 			] as $side){
 				$block = $this->getSide($side);
-				if(!$block->isTransparent()){
+				if($this->canBeSupportedBy($block, Facing::opposite($side))){
 					$this->facing = Facing::opposite($side);
 					return parent::place($tx, $item, $blockReplace, $blockClicked, $face, $clickVector, $player);
 				}
@@ -95,4 +97,9 @@ class Torch extends Flowable{
 		}
 		return false;
 	}
+
+	private function canBeSupportedBy(Block $support, int $face) : bool{
+		return ($face === Facing::UP && $support->getSupportType($face)->hasCenterSupport()) ||
+			(Facing::axis($face) !== Axis::Y && $support->getSupportType($face)->equals(SupportType::FULL()));
+	}
 }

src/block/Trapdoor.php

@@ -25,6 +25,7 @@ namespace pocketmine\block;
 
 use pocketmine\block\utils\BlockDataSerializer;
 use pocketmine\block\utils\HorizontalFacingTrait;
+use pocketmine\block\utils\SupportType;
 use pocketmine\item\Item;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
@@ -78,6 +79,10 @@ class Trapdoor extends Transparent{
 		return [AxisAlignedBB::one()->trim($this->open ? $this->facing : ($this->top ? Facing::DOWN : Facing::UP), 13 / 16)];
 	}
 
+	public function getSupportType(int $facing) : SupportType{
+		return SupportType::NONE();
+	}
+
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		if($player !== null){
 			$this->facing = Facing::opposite($player->getHorizontalFacing());

src/block/Wall.php

@@ -23,6 +23,8 @@ declare(strict_types=1);
 
 namespace pocketmine\block;
 
+use pocketmine\block\utils\SupportType;
+use pocketmine\math\Axis;
 use pocketmine\math\AxisAlignedBB;
 use pocketmine\math\Facing;
 
@@ -76,4 +78,8 @@ class Wall extends Transparent{
 				->trim(Facing::EAST, $east ? 0 : $inset)
 		];
 	}
+
+	public function getSupportType(int $facing) : SupportType{
+		return Facing::axis($facing) === Axis::Y ? SupportType::CENTER() : SupportType::NONE();
+	}
 }

src/block/WallCoralFan.php

@@ -113,7 +113,7 @@ final class WallCoralFan extends BaseCoral{
 
 	public function place(BlockTransaction $tx, Item $item, Block $blockReplace, Block $blockClicked, int $face, Vector3 $clickVector, ?Player $player = null) : bool{
 		$axis = Facing::axis($face);
-		if(($axis !== Axis::X && $axis !== Axis::Z) || !$blockClicked->isSolid()){
+		if(($axis !== Axis::X && $axis !== Axis::Z) || !$this->canBeSupportedBy($blockClicked, $face)){
 			return false;
 		}
 		$this->facing = $face;
@@ -122,10 +122,14 @@ final class WallCoralFan extends BaseCoral{
 
 	public function onNearbyBlockChange() : void{
 		$world = $this->position->getWorld();
-		if(!$world->getBlock($this->position->getSide(Facing::opposite($this->facing)))->isSolid()){
+		if(!$this->canBeSupportedBy($world->getBlock($this->position->getSide(Facing::opposite($this->facing))), $this->facing)){
 			$world->useBreakOn($this->position);
 		}else{
 			parent::onNearbyBlockChange();
 		}
 	}
+
+	private function canBeSupportedBy(Block $block, int $face) : bool{
+		return $block->getSupportType($face)->hasCenterSupport();
+	}
 }

src/block/utils/SupportType.php

@@ -0,0 +1,58 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\block\utils;
+
+use pocketmine\utils\EnumTrait;
+
+/**
+ * This doc-block is generated automatically, do not modify it manually.
+ * This must be regenerated whenever registry members are added, removed or changed.
+ * @see build/generate-registry-annotations.php
+ * @generate-registry-docblock
+ *
+ * @method static SupportType CENTER()
+ * @method static SupportType EDGE()
+ * @method static SupportType FULL()
+ * @method static SupportType NONE()
+ */
+final class SupportType{
+	use EnumTrait;
+
+	protected static function setup() : void{
+		self::registerAll(
+			new self("full"),
+			new self("center"),
+			new self("edge"),
+			new self("none")
+		);
+	}
+
+	public function hasEdgeSupport() : bool{
+		return $this->equals(self::EDGE()) || $this->equals(self::FULL());
+	}
+
+	public function hasCenterSupport() : bool{
+		return $this->equals(self::CENTER()) || $this->equals(self::FULL());
+	}
+}

tests/phpstan/configs/actual-problems.neon

@@ -335,6 +335,21 @@ parameters:
 			count: 3
 			path: ../../../src/block/Mycelium.php
 
+		-
+			message: "#^Parameter \\#1 \\$x of method pocketmine\\\\world\\\\World\\:\\:getFullLightAt\\(\\) expects int, float\\|int given\\.$#"
+			count: 1
+			path: ../../../src/block/RedMushroom.php
+
+		-
+			message: "#^Parameter \\#2 \\$y of method pocketmine\\\\world\\\\World\\:\\:getFullLightAt\\(\\) expects int, float\\|int given\\.$#"
+			count: 1
+			path: ../../../src/block/RedMushroom.php
+
+		-
+			message: "#^Parameter \\#3 \\$z of method pocketmine\\\\world\\\\World\\:\\:getFullLightAt\\(\\) expects int, float\\|int given\\.$#"
+			count: 1
+			path: ../../../src/block/RedMushroom.php
+
 		-
 			message: "#^Parameter \\#1 \\$x of method pocketmine\\\\world\\\\World\\:\\:getBlockLightAt\\(\\) expects int, float\\|int given\\.$#"
 			count: 1