From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Thu, 23 Jul 2015 07:21:00 +0000 (+0200)
Subject: propagate light into blocking blocks
X-Git-Url: https://git.localhorst.tv/?a=commitdiff_plain;ds=sidebyside;h=695918769a616db82dbebb987ea91f3204dee8a9;p=blank.git

propagate light into blocking blocks

this way semi-filled blocks like slabs don't blacken surfaces
behind them, but they will be bright when part of a 1 thick wall
---

diff --git a/TODO b/TODO
index 7e52a23..5fc2e9e 100644
--- a/TODO
+++ b/TODO
@@ -54,6 +54,10 @@ entity ai
 	I kinda mitigated it a little for direct neighbors during linking, but
 	it still can happen in (hopefully) rare corner cases
 
+	propagation through semi-filled blocks is wonky. I worked around it by
+	having the light propagate into solid blocks, but feels like this
+	could cause some weird behaviours
+
 gravity
 
 	maybe like light levels? should also store a direction with it in
diff --git a/src/world/chunk.cpp b/src/world/chunk.cpp
index ef3c5fc..c421be9 100644
--- a/src/world/chunk.cpp
+++ b/src/world/chunk.cpp
@@ -65,9 +65,13 @@ struct SetNode {
 	int Get() const noexcept { return chunk->GetLight(pos); }
 	void Set(int level) noexcept { chunk->SetLight(pos, level); }
 
+	const BlockType &GetType() const noexcept { return chunk->Type(Chunk::ToIndex(pos)); }
+
 	bool HasNext(Block::Face face) noexcept {
+		const BlockType &type = GetType();
+		if (type.block_light && !type.luminosity) return false;
 		const BlockLookup next(chunk, pos, face);
-		return next && !next.GetType().block_light;
+		return next;
 	}
 	SetNode GetNext(Block::Face face) noexcept {
 		const BlockLookup next(chunk, pos, face);
diff --git a/tst/world/ChunkTest.cpp b/tst/world/ChunkTest.cpp
index 6db245a..c8dac83 100644
--- a/tst/world/ChunkTest.cpp
+++ b/tst/world/ChunkTest.cpp
@@ -450,10 +450,6 @@ void ChunkTest::testLightPropagation() {
 
 	// now block the light to the left
 	chunk->SetBlock(Chunk::Pos(6, 7, 7), Block(1));
-	CPPUNIT_ASSERT_EQUAL_MESSAGE(
-		"non-zero light level in solid block",
-		0, chunk->GetLight(Chunk::Pos(6, 7, 7))
-	);
 	CPPUNIT_ASSERT_EQUAL_MESSAGE(
 		"adding obstacle affected unrelated index",
 		5, chunk->GetLight(Chunk::Pos(7, 7, 7))