Block light bug fixes (#454)

* Fixed an age-old light calculation bug causing solid blocks to filter their own light, fixed #375, probably fixed #288
Light spread reduction should be done based on the _target's_ light filter level, not the source.

* Revert "Fix Glowing Obsidian lighting"
This hack is no longer necessary.
This reverts commit 35c33ba980887e9680d62bbcb65f8537bb063f2c.

* Fixed wrong light levels for torch and redstone torch

* Take adjacent light levels and opacity changes into account, block light will now spread when an obstruction is removed, close #455

* Added timings for Level->setBlock() and lighting updates

src/pocketmine/block/GlowingObsidian.php

@@ -22,7 +22,7 @@
 namespace pocketmine\block;
 
 
-class GlowingObsidian extends Transparent{
+class GlowingObsidian extends Solid{
 
 	protected $id = self::GLOWING_OBSIDIAN;
 

src/pocketmine/block/RedstoneTorch.php

@@ -32,4 +32,8 @@ class RedstoneTorch extends Torch{
 	public function getName(){
 		return "Redstone Torch";
 	}
+
+	public function getLightLevel(){
+		return 7;
+	}
 }

src/pocketmine/block/Torch.php

@@ -34,7 +34,7 @@ class Torch extends Flowable{
 	}
 
 	public function getLightLevel(){
-		return 15;
+		return 14;
 	}
 
 	public function getName(){

src/pocketmine/event/LevelTimings.php

@@ -25,6 +25,13 @@ use pocketmine\level\Level;
 
 class LevelTimings{
 
+	/** @var TimingsHandler */
+	public $setBlock;
+	/** @var TimingsHandler */
+	public $doBlockLightUpdates;
+	/** @var TimingsHandler */
+	public $doBlockSkyLightUpdates;
+
 	/** @var TimingsHandler */
 	public $mobSpawn;
 	/** @var TimingsHandler */
@@ -79,6 +86,10 @@ class LevelTimings{
 	public function __construct(Level $level){
 		$name = $level->getFolderName() . " - ";
 
+		$this->setBlock = new TimingsHandler("** " . $name . "setBlock");
+		$this->doBlockLightUpdates = new TimingsHandler("** " . $name . "doBlockLightUpdates");
+		$this->doBlockSkyLightUpdates = new TimingsHandler("** " . $name . "doBlockSkyLightUpdates");
+
 		$this->mobSpawn = new TimingsHandler("** " . $name . "mobSpawn");
 		$this->doChunkUnload = new TimingsHandler("** " . $name . "doChunkUnload");
 		$this->doTickPending = new TimingsHandler("** " . $name . "doTickPending");

src/pocketmine/level/Level.php

@@ -1286,17 +1286,42 @@ class Level implements ChunkManager, Metadatable{
 	}
 
 	public function updateBlockSkyLight(int $x, int $y, int $z){
+		$this->timings->doBlockSkyLightUpdates->startTiming();
 		//TODO
+		$this->timings->doBlockSkyLightUpdates->stopTiming();
+	}
+
+	/**
+	 * Returns the highest light level available in the positions adjacent to the specified block coordinates.
+	 *
+	 * @param int $x
+	 * @param int $y
+	 * @param int $z
+	 *
+	 * @return int
+	 */
+	public function getHighestAdjacentBlockLight(int $x, int $y, int $z) : int{
+		return max([
+			$this->getBlockLightAt($x + 1, $y, $z),
+			$this->getBlockLightAt($x - 1, $y, $z),
+			$this->getBlockLightAt($x, $y + 1, $z),
+			$this->getBlockLightAt($x, $y - 1, $z),
+			$this->getBlockLightAt($x, $y, $z + 1),
+			$this->getBlockLightAt($x, $y, $z - 1)
+		]);
 	}
 
 	public function updateBlockLight(int $x, int $y, int $z){
+		$this->timings->doBlockLightUpdates->startTiming();
+
 		$lightPropagationQueue = new \SplQueue();
 		$lightRemovalQueue = new \SplQueue();
 		$visited = [];
 		$removalVisited = [];
 
+		$id = $this->getBlockIdAt($x, $y, $z);
 		$oldLevel = $this->getBlockLightAt($x, $y, $z);
-		$newLevel = (int) Block::$light[$this->getBlockIdAt($x, $y, $z)];
+		$newLevel = max(Block::$light[$id], $this->getHighestAdjacentBlockLight($x, $y, $z) - Block::$lightFilter[$id]);
 
 		if($oldLevel !== $newLevel){
 			$this->setBlockLightAt($x, $y, $z, $newLevel);
@@ -1328,7 +1353,7 @@ class Level implements ChunkManager, Metadatable{
 			/** @var Vector3 $node */
 			$node = $lightPropagationQueue->dequeue();
 
-			$lightLevel = $this->getBlockLightAt($node->x, $node->y, $node->z) - (int) Block::$lightFilter[$this->getBlockIdAt($node->x, $node->y, $node->z)];
+			$lightLevel = $this->getBlockLightAt($node->x, $node->y, $node->z);
 
 			if($lightLevel >= 1){
 				$this->computeSpreadBlockLight($node->x - 1, $node->y, $node->z, $lightLevel, $lightPropagationQueue, $visited);
@@ -1339,6 +1364,8 @@ class Level implements ChunkManager, Metadatable{
 				$this->computeSpreadBlockLight($node->x, $node->y, $node->z + 1, $lightLevel, $lightPropagationQueue, $visited);
 			}
 		}
+
+		$this->timings->doBlockLightUpdates->stopTiming();
 	}
 
 	private function computeRemoveBlockLight(int $x, int $y, int $z, int $currentLight, \SplQueue $queue, \SplQueue $spreadQueue, array &$visited, array &$spreadVisited){
@@ -1365,6 +1392,7 @@ class Level implements ChunkManager, Metadatable{
 	private function computeSpreadBlockLight(int $x, int $y, int $z, int $currentLight, \SplQueue $queue, array &$visited){
 		if($y < 0) return;
 		$current = $this->getBlockLightAt($x, $y, $z);
+		$currentLight -= Block::$lightFilter[$this->getBlockIdAt($x, $y, $z)];
 
 		if($current < $currentLight){
 			$this->setBlockLightAt($x, $y, $z, $currentLight);
@@ -1402,6 +1430,8 @@ class Level implements ChunkManager, Metadatable{
 			return false;
 		}
 
+		$this->timings->setBlock->startTiming();
+
 		if($this->getChunk($pos->x >> 4, $pos->z >> 4, true)->setBlock($pos->x & 0x0f, $pos->y & Level::Y_MASK, $pos->z & 0x0f, $block->getId(), $block->getDamage())){
 			if(!($pos instanceof Position)){
 				$pos = $this->temporalPosition->setComponents($pos->x, $pos->y, $pos->z);
@@ -1441,9 +1471,13 @@ class Level implements ChunkManager, Metadatable{
 				$this->updateAround($pos);
 			}
 
+			$this->timings->setBlock->stopTiming();
+
 			return true;
 		}
 
+		$this->timings->setBlock->stopTiming();
+
 		return false;
 	}