Chunk iterator and fix getter

include/mcpp/util.h

@@ -92,6 +92,97 @@ struct Coordinate {
  * the base point they were gathered at and each other.
  */
 struct Chunk {
+    /**
+     * @brief An iterator for the Chunk's 3D block data.
+     *
+     * This iterator allows for range-based for loops and standard iterator
+     * operations over the 3D block data stored within a Chunk. It provides a
+     * linear interface to traverse the 3D grid of blocks, enabling sequential
+     * access to the elements stored in the chunk.
+     */
+    struct Iterator {
+        using value_type = BlockType;
+        using pointer = BlockType*;
+        using reference = BlockType&;
+
+        /**
+         * @brief Constructs an iterator at the given pointer position.
+         *
+         * @param ptr Pointer to the position in the height array.
+         */
+        Iterator(pointer ptr) : m_ptr(ptr) {}
+
+        /**
+         * @brief Dereference the iterator to access the value at the current
+         * position.
+         *
+         * @return Reference to the current element.
+         */
+        reference operator*() const { return *m_ptr; }
+
+        /**
+         * @brief Access the pointer to the current element.
+         *
+         * @return Pointer to the current element.
+         */
+        pointer operator->() { return m_ptr; }
+
+        /**
+         * @brief Pre-increment operator. Advances the iterator to the next
+         * position.
+         *
+         * @return Reference to the updated iterator.
+         */
+        Iterator& operator++() {
+            m_ptr++;
+            return *this;
+        }
+
+        /**
+         * @brief Post-increment operator. Advances the iterator to the next
+         * position.
+         *
+         * @param int Unused dummy parameter to differentiate from prefix
+         * increment.
+         * @return Iterator to the original position before incrementing.
+         */
+        Iterator operator++(int) {
+            Iterator tmp = *this;
+            ++(*this);
+            return tmp;
+        }
+
+        /**
+         * @brief Equality comparison operator.
+         *
+         * @param a First iterator to compare.
+         * @param b Second iterator to compare.
+         * @return true if both iterators point to the same position, false
+         * otherwise.
+         */
+        friend bool operator==(const Iterator& a, const Iterator& b) {
+            return a.m_ptr == b.m_ptr;
+        };
+
+        /**
+         * @brief Inequality comparison operator.
+         *
+         * @param a First iterator to compare.
+         * @param b Second iterator to compare.
+         * @return true if iterators point to different positions, false
+         * otherwise.
+         */
+        friend bool operator!=(const Iterator& a, const Iterator& b) {
+            return a.m_ptr != b.m_ptr;
+        };
+
+      private:
+        pointer m_ptr;
+    };
+
+    Iterator begin() { return Iterator(&raw_data[0]); }
+    Iterator end() { return Iterator(&raw_data[_x_len * _y_len * _z_len]); }
+
     /**
      * Initialized by copying from a flat vector of blocks
      */

src/util.cpp

@@ -96,7 +96,7 @@ BlockType Chunk::get(int x, int y, int z) {
         throw std::out_of_range("Out of bounds Chunk access at " +
                                 to_string(Coordinate(x, y, z)));
     }
-    return raw_data[z + _z_len * (x + _y_len * y)];
+    return raw_data[y * _x_len * _z_len + x * _z_len + z];
 }
 
 BlockType Chunk::get_worldspace(const Coordinate& pos) {
@@ -108,8 +108,8 @@ BlockType Chunk::get_worldspace(const Coordinate& pos) {
                                 to_string(array_pos) + " (world coordinate " +
                                 to_string(pos) + " )");
     }
-    return raw_data[array_pos.z +
-                    _z_len * (array_pos.x + _y_len * array_pos.y)];
+    return raw_data[array_pos.y * _x_len * _z_len + array_pos.x * _z_len +
+                    array_pos.z];
 }
 
 int Chunk::x_len() const { return this->_x_len; }

test/minecraft_tests.cpp

@@ -127,10 +127,11 @@ TEST_CASE("Test the main mcpp class") {
 }
 
 TEST_CASE("getBlocks and Chunk operations") {
+
     // Setup
     Coordinate test_loc(100, 100, 100);
     Coordinate loc1{100, 100, 100};
-    Coordinate loc2{110, 110, 110};
+    Coordinate loc2{110, 111, 112};
 
     // Reset blocks that existed before
     mc.setBlocks(loc1, loc2, Blocks::AIR);
@@ -145,22 +146,22 @@ TEST_CASE("getBlocks and Chunk operations") {
 
         CHECK_EQ(data.base_pt(), loc1);
         CHECK_EQ(data.x_len(), 11);
-        CHECK_EQ(data.y_len(), 11);
-        CHECK_EQ(data.z_len(), 11);
+        CHECK_EQ(data.y_len(), 12);
+        CHECK_EQ(data.z_len(), 13);
 
         data = mc.getBlocks(loc2, loc1);
 
         CHECK_EQ(data.base_pt(), loc1);
         CHECK_EQ(data.x_len(), 11);
-        CHECK_EQ(data.y_len(), 11);
-        CHECK_EQ(data.z_len(), 11);
+        CHECK_EQ(data.y_len(), 12);
+        CHECK_EQ(data.z_len(), 13);
     }
 
     SUBCASE("Block accessing returns correct block using get()") {
         CHECK_EQ(res.get(0, 0, 0), Blocks::GOLD_BLOCK);
         CHECK_EQ(res.get(1, 1, 1), Blocks::BRICKS);
         CHECK_EQ(res.get(1, 2, 3), Blocks::IRON_BLOCK);
-        CHECK_EQ(res.get(10, 10, 10), Blocks::DIAMOND_BLOCK);
+        CHECK_EQ(res.get(10, 11, 12), Blocks::DIAMOND_BLOCK);
     }
 
     SUBCASE("Block accessing returns correct block using get_worldspace()") {
@@ -174,13 +175,30 @@ TEST_CASE("getBlocks and Chunk operations") {
 
     SUBCASE("Access out of bounds correctly throws") {
         CHECK_THROWS(res.get(11, 0, 0));
-        CHECK_THROWS(res.get(0, 11, 0));
-        CHECK_THROWS(res.get(0, 0, 11));
+        CHECK_THROWS(res.get(0, 12, 0));
+        CHECK_THROWS(res.get(0, 0, 13));
         CHECK_THROWS(res.get(-1, 0, 0));
         CHECK_THROWS(res.get(0, -1, 0));
         CHECK_THROWS(res.get(0, 0, -1));
         CHECK_THROWS(res.get_worldspace(loc1 + Coordinate{-1, -1, -1}));
-        CHECK_THROWS(res.get_worldspace(loc1 + Coordinate{11, 11, 11}));
+        CHECK_THROWS(res.get_worldspace(loc1 + Coordinate{11, 12, 13}));
+    }
+
+    SUBCASE("Iterator") {
+        std::vector<BlockType> blocks;
+        for (int i = 0; i < res.y_len(); i++) {
+            for (int j = 0; j < res.x_len(); j++) {
+                for (int z = 0; z < res.z_len(); z++) {
+                    blocks.push_back(res.get(j, i, z));
+                }
+            }
+        }
+
+        std::vector<BlockType> expected_blocks;
+        for (BlockType block : res) {
+            expected_blocks.push_back(block);
+        }
+        CHECK_EQ(blocks, expected_blocks);
     }
 
     mc.setBlock(test_loc, BlockType(0));