better edge light propagation on link

diff --git a/TODO b/TODO
index a0c8c1dee83a343e53e6fd983be20da62aa431f7..4025ad59c5c8cc5c367a6085c8e5de80e8d363d5 100644 (file)
--- a/TODO
+++ b/TODO
@@ -50,6 +50,8 @@ entity ai
 
        there's a bug where a chunk's model is not updated if its neighbor
        changes border light levels
+       I kinda mitigated it a little for direct neighbors during linking, but
+       it still can happen in (hopefully) rare corner cases
 
 gravity
 

diff --git a/src/world/chunk.cpp b/src/world/chunk.cpp
index a65f5c31d9b1d0081ab3204903b87cbe10bd562d..75f9c4f424c28d8babc77ef9322921a7db96a899 100644 (file)
--- a/src/world/chunk.cpp
+++ b/src/world/chunk.cpp
@@ -186,6 +186,26 @@ void Chunk::SetBlock(int index, const Block &block) noexcept {
        }
 }
 
+namespace {
+
+// propagate light from a's edge to b
+void edge_light(
+       Chunk &a, const Chunk::Pos &a_pos,
+       Chunk &b, const Chunk::Pos &b_pos
+) noexcept {
+       if (a.GetLight(a_pos) > 1) {
+               const BlockType &b_type = b.Type(Chunk::ToIndex(b_pos));
+               if (!b_type.block_light) {
+                       light_queue.emplace(&a, a_pos);
+               }
+               if (b_type.visible) {
+                       b.Invalidate();
+               }
+       }
+}
+
+}
+
 void Chunk::SetNeighbor(Chunk &other) noexcept {
        if (other.position == position + Pos(-1, 0, 0)) {
                if (neighbor[Block::FACE_LEFT] != &other) {
@@ -195,12 +215,8 @@ void Chunk::SetNeighbor(Chunk &other) noexcept {
                                for (int y = 0; y < height; ++y) {
                                        Pos my_pos(0, y, z);
                                        Pos other_pos(width - 1, y, z);
-                                       if (GetLight(my_pos) > 0) {
-                                               light_queue.emplace(this, my_pos);
-                                       }
-                                       if (other.GetLight(other_pos) > 0) {
-                                               light_queue.emplace(&other, other_pos);
-                                       }
+                                       edge_light(*this, my_pos, other, other_pos);
+                                       edge_light(other, other_pos, *this, my_pos);
                                }
                        }
                        work_light();
@@ -213,12 +229,8 @@ void Chunk::SetNeighbor(Chunk &other) noexcept {
                                for (int y = 0; y < height; ++y) {
                                        Pos my_pos(width - 1, y, z);
                                        Pos other_pos(0, y, z);
-                                       if (GetLight(my_pos) > 0) {
-                                               light_queue.emplace(this, my_pos);
-                                       }
-                                       if (other.GetLight(other_pos) > 0) {
-                                               light_queue.emplace(&other, other_pos);
-                                       }
+                                       edge_light(*this, my_pos, other, other_pos);
+                                       edge_light(other, other_pos, *this, my_pos);
                                }
                        }
                        work_light();
@@ -231,12 +243,8 @@ void Chunk::SetNeighbor(Chunk &other) noexcept {
                                for (int x = 0; x < width; ++x) {
                                        Pos my_pos(x, 0, z);
                                        Pos other_pos(x, height - 1, z);
-                                       if (GetLight(my_pos) > 0) {
-                                               light_queue.emplace(this, my_pos);
-                                       }
-                                       if (other.GetLight(other_pos) > 0) {
-                                               light_queue.emplace(&other, other_pos);
-                                       }
+                                       edge_light(*this, my_pos, other, other_pos);
+                                       edge_light(other, other_pos, *this, my_pos);
                                }
                        }
                        work_light();
@@ -249,12 +257,8 @@ void Chunk::SetNeighbor(Chunk &other) noexcept {
                                for (int x = 0; x < width; ++x) {
                                        Pos my_pos(x, height - 1, z);
                                        Pos other_pos(x, 0, z);
-                                       if (GetLight(my_pos) > 0) {
-                                               light_queue.emplace(this, my_pos);
-                                       }
-                                       if (other.GetLight(other_pos) > 0) {
-                                               light_queue.emplace(&other, other_pos);
-                                       }
+                                       edge_light(*this, my_pos, other, other_pos);
+                                       edge_light(other, other_pos, *this, my_pos);
                                }
                        }
                        work_light();
@@ -267,12 +271,8 @@ void Chunk::SetNeighbor(Chunk &other) noexcept {
                                for (int x = 0; x < width; ++x) {
                                        Pos my_pos(x, y, 0);
                                        Pos other_pos(x, y, depth - 1);
-                                       if (GetLight(my_pos) > 0) {
-                                               light_queue.emplace(this, my_pos);
-                                       }
-                                       if (other.GetLight(other_pos) > 0) {
-                                               light_queue.emplace(&other, other_pos);
-                                       }
+                                       edge_light(*this, my_pos, other, other_pos);
+                                       edge_light(other, other_pos, *this, my_pos);
                                }
                        }
                        work_light();
@@ -285,12 +285,8 @@ void Chunk::SetNeighbor(Chunk &other) noexcept {
                                for (int x = 0; x < width; ++x) {
                                        Pos my_pos(x, y, depth - 1);
                                        Pos other_pos(x, y, 0);
-                                       if (GetLight(my_pos) > 0) {
-                                               light_queue.emplace(this, my_pos);
-                                       }
-                                       if (other.GetLight(other_pos) > 0) {
-                                               light_queue.emplace(&other, other_pos);
-                                       }
+                                       edge_light(*this, my_pos, other, other_pos);
+                                       edge_light(other, other_pos, *this, my_pos);
                                }
                        }
                        work_light();