Add attached tileset class

modules/core/inc/tactile/core/tileset/attached_tileset.hpp

@@ -0,0 +1,89 @@
+// Copyright (C) 2023 Albin Johansson (GNU General Public License v3.0)
+
+#pragma once
+
+#include "tactile/core/api.hpp"
+#include "tactile/core/container/smart_ptr.hpp"
+#include "tactile/core/functional/maybe.hpp"
+#include "tactile/core/misc/id_types.hpp"
+#include "tactile/core/prelude.hpp"
+#include "tactile/core/tileset/tileset.hpp"
+
+namespace tactile {
+
+/**
+ * \brief Represents a tileset that is attached to a map.
+ *
+ * \see `Tileset`
+ */
+class TACTILE_CORE_API AttachedTileset final {
+ public:
+  /**
+   * \brief Creates an attached tileset.
+   *
+   * \param tileset       the associated tileset.
+   * \param first_tile_id the global tile identifier to associate with the first tile.
+   */
+  AttachedTileset(Shared<Tileset> tileset, TileID first_tile_id);
+
+  /**
+   * \brief Converts a tile identifier to a tile index.
+   *
+   * \pre The tile identifier must be associated with the attached tileset.
+   *
+   * \param tile_id the tile identifier.
+   *
+   * \return a tile index.
+   *
+   * \see `has_tile()`
+   */
+  [[nodiscard]]
+  auto to_index(TileID tile_id) const -> TileIndex;
+
+  /**
+   * \brief Indicates whether a tile identifier is contained in the tileset.
+   *
+   * \param tile_id the tile identifier.
+   *
+   * \return true if the identifier is valid; false otherwise.
+   */
+  [[nodiscard]]
+  auto has_tile(TileID tile_id) const -> bool;
+
+  /**
+   * \brief Returns the first (lowest) associated tile identifier.
+   *
+   * \return a tile identifier.
+   */
+  [[nodiscard]]
+  auto get_first_tile_id() const -> TileID;
+
+  /**
+   * \brief Returns the last (greatest) associated tile identifier.
+   *
+   * \return a tile identifier.
+   */
+  [[nodiscard]]
+  auto get_last_tile_id() const -> TileID;
+
+  /**
+   * \brief Returns the associated tileset.
+   *
+   * \return a tileset reference.
+   */
+  [[nodiscard]]
+  auto get_tileset() -> Tileset&;
+
+  /**
+   * \copydoc get_tileset()
+   */
+  [[nodiscard]]
+  auto get_tileset() const -> const Tileset&;
+
+ private:
+  Shared<Tileset> mTileset;
+  TileID mFirstTileId;
+  TileID mLastTileId;
+};
+
+}  // namespace tactile

modules/core/src/tactile/core/tileset/attached_tileset.cpp

@@ -0,0 +1,49 @@
+// Copyright (C) 2023 Albin Johansson (GNU General Public License v3.0)
+
+#include "tactile/core/tileset/attached_tileset.hpp"
+
+#include <utility>  // move
+
+#include "tactile/core/debug/assert.hpp"
+#include "tactile/core/debug/error.hpp"
+
+namespace tactile {
+
+AttachedTileset::AttachedTileset(Shared<Tileset> tileset, const TileID first_tile_id)
+  : mTileset {tileset ? std::move(tileset) : throw RuntimeError {"Null tileset"}},
+    mFirstTileId {first_tile_id},
+    mLastTileId {first_tile_id.value + (mTileset->tile_count() - 1)}
+{}
+
+auto AttachedTileset::to_index(const TileID tile_id) const -> TileIndex
+{
+  TACTILE_ASSERT(has_tile(tile_id));
+  return TileIndex {tile_id.value - mFirstTileId.value};
+}
+
+auto AttachedTileset::has_tile(const TileID tile_id) const -> bool
+{
+  return tile_id >= mFirstTileId && tile_id <= mLastTileId;
+}
+
+auto AttachedTileset::get_first_tile_id() const -> TileID
+{
+  return mFirstTileId;
+}
+
+auto AttachedTileset::get_last_tile_id() const -> TileID
+{
+  return mLastTileId;
+}
+
+auto AttachedTileset::get_tileset() -> Tileset&
+{
+  return *mTileset;
+}
+
+auto AttachedTileset::get_tileset() const -> const Tileset&
+{
+  return *mTileset;
+}
+
+}  // namespace tactile

modules/core/test/tileset/attached_tileset_test.cpp

@@ -0,0 +1,59 @@
+// Copyright (C) 2023 Albin Johansson (GNU General Public License v3.0)
+
+#include "tactile/core/tileset/attached_tileset.hpp"
+
+#include <gtest/gtest.h>
+
+#include "tactile/core/debug/error.hpp"
+#include "testutil/tileset_helpers.hpp"
+
+using namespace tactile;
+
+/// \tests tactile::AttachedTileset::AttachedTileset
+TEST(AttachedTileset, ConstructorWithNullTileset)
+{
+  EXPECT_THROW(AttachedTileset(nullptr, TileID {1}), RuntimeError);
+}
+
+/// \tests tactile::AttachedTileset::to_index
+TEST(AttachedTileset, ToIndex)
+{
+  const auto tileset_info = test::make_dummy_tileset_info();
+  const auto tileset = make_shared<Tileset>(tileset_info);
+
+  const AttachedTileset attached_tileset {tileset, TileID {42}};
+  const auto first_id = attached_tileset.get_first_tile_id();
+  const auto last_id = attached_tileset.get_last_tile_id();
+
+  EXPECT_EQ(attached_tileset.to_index(first_id), TileIndex {0});
+  EXPECT_EQ(attached_tileset.to_index(last_id), TileIndex {tileset->tile_count() - 1});
+}
+
+/// \tests tactile::AttachedTileset::has_tile
+TEST(AttachedTileset, HasTile)
+{
+  const auto tileset_info = test::make_dummy_tileset_info();
+  const auto tileset = make_shared<Tileset>(tileset_info);
+
+  const AttachedTileset attached_tileset {tileset, TileID {1}};
+  const auto first_id = attached_tileset.get_first_tile_id();
+  const auto last_id = attached_tileset.get_last_tile_id();
+
+  EXPECT_TRUE(attached_tileset.has_tile(first_id));
+  EXPECT_TRUE(attached_tileset.has_tile(last_id));
+
+  EXPECT_FALSE(attached_tileset.has_tile(TileID {first_id.value - 1}));
+  EXPECT_FALSE(attached_tileset.has_tile(TileID {last_id.value + 1}));
+}
+
+/// \tests tactile::AttachedTileset::get_first_tile_id
+/// \tests tactile::AttachedTileset::get_last_tile_id
+TEST(AttachedTileset, TileIdentifiers)
+{
+  const auto tileset_info = test::make_dummy_tileset_info();
+  const auto tileset = make_shared<Tileset>(tileset_info);
+  const AttachedTileset attached_tileset {tileset, TileID {27}};
+
+  EXPECT_EQ(attached_tileset.get_first_tile_id(), TileID {27});
+  EXPECT_EQ(attached_tileset.get_last_tile_id(), TileID {27 + tileset->tile_count() - 1});
+}