From 0464a83dfaebaa75d6e2d3b7431e84ebd83fccfd Mon Sep 17 00:00:00 2001
From: Mel <einebeere@gmail.com>
Date: Tue, 18 Oct 2022 19:09:36 +0200
Subject: Hide inward-facing block faces

---
 src/World/Chunk.cpp | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
 src/World/Chunk.hpp |  6 ++++--
 2 files changed, 53 insertions(+), 3 deletions(-)

diff --git a/src/World/Chunk.cpp b/src/World/Chunk.cpp
index 73aab3d..1d541f7 100644
--- a/src/World/Chunk.cpp
+++ b/src/World/Chunk.cpp
@@ -21,6 +21,10 @@ Mesh Chunk::mesh() {
                 }
 
                 for (auto side: BlockSide::all()) {
+                    if (!is_face_visible(x, y, z, side)) {
+                        continue;
+                    }
+
                     auto side_tex_coords = Chunk::face_tex_coords(type, side);
                     auto side_positions = side.face();
 
@@ -41,6 +45,49 @@ Mesh Chunk::mesh() {
     return {positions, tex_coords, indices};
 }
 
+bool Chunk::is_face_visible(uint32_t x, uint32_t y, uint32_t z, BlockSide side) {
+    Vector<3, int32_t> offset{};
+    switch (side) {
+        case BlockSide::Front:
+            offset[2] = 1;
+            break;
+        case BlockSide::Back:
+            offset[2] = -1;
+            break;
+        case BlockSide::Top:
+            offset[1] = 1;
+            break;
+        case BlockSide::Bottom:
+            offset[1] = -1;
+            break;
+        case BlockSide::Left:
+            offset[0] = -1;
+            break;
+        case BlockSide::Right:
+            offset[0] = 1;
+            break;
+    }
+
+    Vector<3, uint32_t> neighbor_pos{
+        x + offset.x(), y + offset.y(), z + offset.z(),
+    };
+
+    if (
+        neighbor_pos.x() >= CHUNK_WIDTH || neighbor_pos.x() < 0 ||
+        neighbor_pos.y() >= CHUNK_HEIGHT || neighbor_pos.y() < 0 ||
+        neighbor_pos.z() >= CHUNK_WIDTH || neighbor_pos.z() < 0
+    ) {
+        return true;
+    }
+
+    auto neighbor = m_blocks[neighbor_pos.x()][neighbor_pos.y()][neighbor_pos.z()];
+    if (neighbor.type == BlockType::Air) {
+        return true;
+    }
+
+    return false;
+}
+
 std::array<Vector<2>, 4> Chunk::face_tex_coords(BlockType type, BlockSide side) {
     switch (type) {
         case BlockType::Dirt:
@@ -67,6 +114,7 @@ std::array<Vector<2>, 4> Chunk::face_tex_coords(BlockType type, BlockSide side)
             }
         default:
             return {};
-    }}
+    }
+}
 
 }
diff --git a/src/World/Chunk.hpp b/src/World/Chunk.hpp
index eafc613..0a5f269 100644
--- a/src/World/Chunk.hpp
+++ b/src/World/Chunk.hpp
@@ -5,8 +5,8 @@
 #include "../Mesh.hpp"
 #include "BlockSide.hpp"
 
-#define CHUNK_WIDTH 8
-#define CHUNK_HEIGHT 8
+#define CHUNK_WIDTH 16
+#define CHUNK_HEIGHT 32
 
 namespace MC {
 
@@ -18,6 +18,8 @@ public:
 
     Mesh mesh();
 private:
+    bool is_face_visible(uint32_t x, uint32_t y, uint32_t z, BlockSide side);
+
     static std::array<Vector<2>, 4> face_tex_coords(BlockType type, BlockSide side);
 
     struct BlockData {
-- 
cgit 1.4.1