Traverse all chunk blocks in a unified (and cache-friendly) way

2 files changed, 49 insertions, 60 deletions

diff --git a/src/World/Generation/ChunkMeshing.hpp b/src/World/Generation/ChunkMeshing.hpp
index c745a3b..16ba701 100644
--- a/src/World/Generation/ChunkMeshing.hpp
+++ b/src/World/Generation/ChunkMeshing.hpp
@@ -47,29 +47,26 @@ template <typename Decisions>
 GFX::Mesh create_mesh(Chunk& chunk, const SurroundingContext& context) {
     GFX::Util::MeshBuilder<Normal, TexCoord, Light, AO> builder;
 
-    for (Int x = 0; x < Chunk::Width; x++) {
-        for (Int y = 0; y < Chunk::Height; y++) {
-            for (Int z = 0; z < Chunk::Width; z++) {
-                auto block = chunk.at(x, y, z);
-                if (Decisions::should_ignore_block(block))
-                    continue;
-
-                for (auto side: BlockSide::all()) {
-                    if (!Decisions::is_face_visible(chunk, context, x, y, z, side))
-                        continue;
-
-                    U32 s = builder.vertex_count();
-
-                    builder.positions(Decisions::face_positions(side, x, y, z));
-                    builder.attributes<0>(Decisions::face_normals(side));
-                    builder.attributes<1>(Decisions::face_tex_coords(block.type, side));
-                    builder.attributes<2>(Decisions::face_light(chunk, context, x, y, z, side));
-                    builder.attributes<3>(Decisions::face_ao_values(chunk, context, x, y, z, side));
-                    builder.indices(std::array{ s + 0, s + 1, s + 2, s + 2, s + 3, s + 0 });
-                }
-            }
+    chunk.for_each([&](Position::BlockLocal pos, Chunk::BlockData block) {
+        auto [x, y, z] = pos.values();
+        if (Decisions::should_ignore_block(block)) return Iteration::Continue;
+
+        for (auto side: BlockSide::all()) {
+            if (!Decisions::is_face_visible(chunk, context, x, y, z, side))
+                continue;
+
+            builder.positions(Decisions::face_positions(side, x, y, z));
+            builder.attributes<0>(Decisions::face_normals(side));
+            builder.attributes<1>(Decisions::face_tex_coords(block.type, side));
+            builder.attributes<2>(Decisions::face_light(chunk, context, x, y, z, side));
+            builder.attributes<3>(Decisions::face_ao_values(chunk, context, x, y, z, side));
+
+            U32 s = builder.vertex_count();
+            builder.indices(std::array{ s + 0, s + 1, s + 2, s + 2, s + 3, s + 0 });
         }
-    }
+
+        return Iteration::Continue;
+    });
 
     return builder.mesh();
 }
diff --git a/src/World/Generation/Decoration.cpp b/src/World/Generation/Decoration.cpp
index 0623c05..ecfa49b 100644
--- a/src/World/Generation/Decoration.cpp
+++ b/src/World/Generation/Decoration.cpp
@@ -43,35 +43,31 @@ void Decorator::draw_circle(Chunk& chunk, Pos pos, Vector<3> axis, Real radius,
 
 void TreeDecorator::decorate_chunk(Chunk& chunk) {
     Pos last_tree = Pos::max();
-    for (UInt x = 0; x < Chunk::Width; x++) {
-        for (UInt z = 0; z < Chunk::Width; z++) {
-            for (UInt y = Chunk::Height - 1; y != 0; y--) {
-                Pos pos{x, y, z};
-                if (!is_valid_position(pos))
-                    continue;
-
-                auto& block_below = chunk.at(x, y-1, z);
-                if (block_below.empty())
-                    continue;
-
-                auto type = block_below.type;
-                if (type != BlockType::Snow && type != BlockType::Grass && type != BlockType::Dirt)
-                    break;
-
-                auto noise = m_tree_noise.at({(Real)x, (Real)z});
-                if (noise < 0.8f)
-                    continue;
-
-                if (last_tree.distance(pos) < s_tree_radius * 3)
-                    continue;
-
-                draw_tree(chunk, pos);
-                block_below = {BlockType::Dirt};
-                last_tree = pos;
-                break;
-            }
-        }
-    }
+    chunk.for_each_by_column([&](Pos pos, Chunk::BlockData& block) {
+        auto pos_above = pos + Pos::up();
+        if (!is_valid_position(pos_above))
+            return Chunk::ColumnIteration::Continue;
+
+        if (block.empty())
+            return Chunk::ColumnIteration::Continue;
+
+        auto type = block.type;
+        if (type != BlockType::Snow && type != BlockType::Grass && type != BlockType::Dirt)
+            return Chunk::ColumnIteration::SkipColumn;
+
+        auto noise = m_tree_noise.at({TO(Real, pos.x()), TO(Real, pos.z())});
+        if (noise < 0.8f)
+            return Chunk::ColumnIteration::Continue;
+
+        if (last_tree.distance(pos_above) < s_tree_radius * 3)
+            return Chunk::ColumnIteration::Continue;
+
+        draw_tree(chunk, pos_above);
+        block = {BlockType::Dirt};
+        last_tree = pos_above;
+
+        return Chunk::ColumnIteration::SkipColumn;
+    });
 }
 
 void TreeDecorator::draw_tree(Chunk& chunk, Pos pos) const {
@@ -97,15 +93,11 @@ Bool TreeDecorator::is_valid_position(Pos pos) {
 }
 
 void DefaultLightDecorator::decorate_chunk(Chunk& chunk) {
-    for (UInt x = 0; x < Chunk::Width; x++) {
-        for (UInt z = 0; z < Chunk::Width; z++) {
-            for (UInt y = Chunk::Height - 1; y != 0; y--) {
-                auto& block = chunk.at(x, y, z);
-                if (!block.type.is_translucent()) break;
-                chunk.at(x, y, z).light = 200;
-            }
-        }
-    }
+    chunk.for_each_by_column([&](Pos pos, Chunk::BlockData& block) {
+        if (!block.type.is_translucent()) return Chunk::ColumnIteration::Break;
+        block.light = 200;
+        return Chunk::ColumnIteration::Continue;
+    });
 }
 
 }