Add OptionalCelSprite: smaller than std::optional

`CelSprite` data pointer can never be `nullptr`.

We implement a smaller `optional` for it by taking advantage of that.

Source/debug.h

@@ -10,7 +10,6 @@
 #include "engine.h"
 #include "engine/cel_sprite.hpp"
 #include "miniwin/miniwin.h"
-#include "utils/stdcompat/optional.hpp"
 #include "utils/stdcompat/string_view.hpp"
 
 namespace devilution {

Source/engine/animationinfo.cpp

@@ -74,7 +74,7 @@ float AnimationInfo::GetAnimationProgress() const
 	return animationFraction;
 }
 
-void AnimationInfo::SetNewAnimation(std::optional<CelSprite> celSprite, int8_t numberOfFrames, int8_t ticksPerFrame, AnimationDistributionFlags flags /*= AnimationDistributionFlags::None*/, int8_t numSkippedFrames /*= 0*/, int8_t distributeFramesBeforeFrame /*= 0*/, float previewShownGameTickFragments /*= 0.F*/)
+void AnimationInfo::SetNewAnimation(OptionalCelSprite celSprite, int8_t numberOfFrames, int8_t ticksPerFrame, AnimationDistributionFlags flags /*= AnimationDistributionFlags::None*/, int8_t numSkippedFrames /*= 0*/, int8_t distributeFramesBeforeFrame /*= 0*/, float previewShownGameTickFragments /*= 0.F*/)
 {
 	if ((flags & AnimationDistributionFlags::RepeatedAction) == AnimationDistributionFlags::RepeatedAction && distributeFramesBeforeFrame != 0 && NumberOfFrames == numberOfFrames && CurrentFrame + 1 >= distributeFramesBeforeFrame && CurrentFrame != NumberOfFrames - 1) {
 		// We showed the same Animation (for example a melee attack) before but truncated the Animation.
@@ -167,7 +167,7 @@ void AnimationInfo::SetNewAnimation(std::optional<CelSprite> celSprite, int8_t n
 	}
 }
 
-void AnimationInfo::ChangeAnimationData(std::optional<CelSprite> celSprite, int8_t numberOfFrames, int8_t ticksPerFrame)
+void AnimationInfo::ChangeAnimationData(OptionalCelSprite celSprite, int8_t numberOfFrames, int8_t ticksPerFrame)
 {
 	if (numberOfFrames != NumberOfFrames || ticksPerFrame != TicksPerFrame) {
 		// Ensure that the CurrentFrame is still valid and that we disable ADL cause the calculcated values (for example TickModifier) could be wrong

Source/engine/animationinfo.h

@@ -9,7 +9,6 @@
 #include <type_traits>
 
 #include "engine/cel_sprite.hpp"
-#include "utils/stdcompat/optional.hpp"
 
 namespace devilution {
 
@@ -40,7 +39,7 @@ public:
 	/**
 	 * @brief Animation sprite
 	 */
-	std::optional<CelSprite> celSprite;
+	OptionalCelSprite celSprite;
 	/**
 	 * @brief How many game ticks are needed to advance one Animation Frame
 	 */
@@ -83,7 +82,7 @@ public:
 	 * @param distributeFramesBeforeFrame Distribute the numSkippedFrames only before this frame
 	 * @param previewShownGameTickFragments Defines how long (in game ticks fraction) the preview animation was shown
 	 */
-	void SetNewAnimation(std::optional<CelSprite> celSprite, int8_t numberOfFrames, int8_t ticksPerFrame, AnimationDistributionFlags flags = AnimationDistributionFlags::None, int8_t numSkippedFrames = 0, int8_t distributeFramesBeforeFrame = 0, float previewShownGameTickFragments = 0.F);
+	void SetNewAnimation(OptionalCelSprite celSprite, int8_t numberOfFrames, int8_t ticksPerFrame, AnimationDistributionFlags flags = AnimationDistributionFlags::None, int8_t numSkippedFrames = 0, int8_t distributeFramesBeforeFrame = 0, float previewShownGameTickFragments = 0.F);
 
 	/**
 	 * @brief Changes the Animation Data on-the-fly. This is needed if a animation is currently in progress and the player changes his gear.
@@ -91,7 +90,7 @@ public:
 	 * @param numberOfFrames Number of Frames in Animation
 	 * @param ticksPerFrame How many game ticks are needed to advance one Animation Frame
 	 */
-	void ChangeAnimationData(std::optional<CelSprite> celSprite, int8_t numberOfFrames, int8_t ticksPerFrame);
+	void ChangeAnimationData(OptionalCelSprite celSprite, int8_t numberOfFrames, int8_t ticksPerFrame);
 
 	/**
 	 * @brief Process the Animation for a game tick (for example advances the frame)

Source/engine/cel_sprite.hpp

@@ -3,12 +3,15 @@
 #include <memory>
 #include <utility>
 
+#include "appfat.h"
 #include "utils/pointer_value_union.hpp"
 #include "utils/stdcompat/cstddef.hpp"
+#include "utils/stdcompat/optional.hpp"
 
 namespace devilution {
 
 class OwnedCelSprite;
+class OptionalCelSprite;
 
 /**
  * Stores a CEL or CL2 sprite and its width(s).
@@ -61,8 +64,82 @@ public:
 	}
 
 private:
+	// for OptionalCelSprite
+	CelSprite()
+	    : data_ptr_(nullptr)
+	    , width_(nullptr)
+	{
+	}
+
 	const byte *data_ptr_;
 	PointerOrValue<uint16_t> width_;
+
+	friend class OptionalCelSprite;
+};
+
+/**
+ * @brief Equivalent to `std::optional<CelSprite>` but smaller.
+ */
+class OptionalCelSprite {
+public:
+	OptionalCelSprite() = default;
+
+	OptionalCelSprite(CelSprite sprite)
+	    : sprite_(sprite)
+	{
+	}
+
+	explicit OptionalCelSprite(const OwnedCelSprite &owned);
+
+	OptionalCelSprite(std::nullopt_t)
+	    : OptionalCelSprite()
+	{
+	}
+
+	template <typename... Args>
+	CelSprite &emplace(Args &&...args)
+	{
+		sprite_ = CelSprite(std::forward<Args>(args)...);
+		return sprite_;
+	}
+
+	OptionalCelSprite &operator=(CelSprite sprite)
+	{
+		sprite_ = sprite;
+		return *this;
+	}
+
+	OptionalCelSprite &operator=(std::nullopt_t)
+	{
+		sprite_ = {};
+		return *this;
+	}
+
+	CelSprite operator*() const
+	{
+		assert(sprite_.data_ptr_ != nullptr);
+		return sprite_;
+	}
+
+	CelSprite *operator->()
+	{
+		assert(sprite_.data_ptr_ != nullptr);
+		return &sprite_;
+	}
+
+	const CelSprite *operator->() const
+	{
+		assert(sprite_.data_ptr_ != nullptr);
+		return &sprite_;
+	}
+
+	operator bool() const
+	{
+		return sprite_.data_ptr_ != nullptr;
+	}
+
+private:
+	CelSprite sprite_;
 };
 
 /**
@@ -103,6 +180,11 @@ inline CelSprite::CelSprite(const OwnedCelSprite &owned)
 {
 }
 
+inline OptionalCelSprite::OptionalCelSprite(const OwnedCelSprite &owned)
+{
+	sprite_ = CelSprite { owned };
+}
+
 struct CelSpriteWithFrameHeight {
 	CelSprite sprite;
 	unsigned frameHeight;

Source/engine/render/scrollrt.cpp

@@ -509,7 +509,7 @@ void DrawPlayer(const Surface &out, const Player &player, Point tilePosition, Po
 		return;
 	}
 
-	std::optional<CelSprite> sprite = player.AnimInfo.celSprite;
+	OptionalCelSprite sprite = player.AnimInfo.celSprite;
 	int nCel = player.AnimInfo.GetFrameToUseForRendering();
 
 	if (player.previewCelSprite) {
@@ -713,7 +713,7 @@ void DrawItem(const Surface &out, Point tilePosition, Point targetBufferPosition
 	if (item._iPostDraw == pre)
 		return;
 
-	std::optional<CelSprite> cel = item.AnimInfo.celSprite;
+	OptionalCelSprite cel = item.AnimInfo.celSprite;
 	if (!cel) {
 		Log("Draw Item \"{}\" 1: NULL CelSprite", item._iIName);
 		return;

Source/items.cpp

@@ -4582,7 +4582,7 @@ void Item::setNewAnimation(bool showAnimation)
 {
 	int8_t it = ItemCAnimTbl[_iCurs];
 	int8_t numberOfFrames = ItemAnimLs[it];
-	auto celSprite = itemanims[it] ? std::optional<CelSprite> { *itemanims[it] } : std::nullopt;
+	auto celSprite = itemanims[it] ? OptionalCelSprite { *itemanims[it] } : std::nullopt;
 	if (_iCurs != ICURS_MAGIC_ROCK)
 		AnimInfo.SetNewAnimation(celSprite, numberOfFrames, 1, AnimationDistributionFlags::ProcessAnimationPending, 0, numberOfFrames);
 	else

Source/monster.h

@@ -20,7 +20,6 @@
 #include "monstdat.h"
 #include "spelldat.h"
 #include "textdat.h"
-#include "utils/stdcompat/optional.hpp"
 
 namespace devilution {
 
@@ -133,7 +132,7 @@ enum class LeaderRelation : uint8_t {
 };
 
 struct AnimStruct {
-	[[nodiscard]] std::optional<CelSprite> getCelSpritesForDirection(Direction direction) const
+	[[nodiscard]] OptionalCelSprite getCelSpritesForDirection(Direction direction) const
 	{
 		const byte *spriteData = celSpritesForDirections[static_cast<size_t>(direction)];
 		if (spriteData == nullptr)

Source/panels/charpanel.hpp

@@ -2,7 +2,6 @@
 
 #include "engine/cel_sprite.hpp"
 #include "engine/surface.hpp"
-#include "utils/stdcompat/optional.hpp"
 
 namespace devilution {
 

Source/panels/info_box.hpp

@@ -1,7 +1,6 @@
 #pragma once
 
 #include "engine/cel_sprite.hpp"
-#include "utils/stdcompat/optional.hpp"
 
 namespace devilution {
 

Source/player.cpp

@@ -368,7 +368,7 @@ void StartWalk(int pnum, Displacement vel, Direction dir, bool pmWillBeCalled)
 	StartWalkAnimation(player, dir, pmWillBeCalled);
 }
 
-void SetPlayerGPtrs(const char *path, std::unique_ptr<byte[]> &data, std::array<std::optional<CelSprite>, 8> &anim, int width)
+void SetPlayerGPtrs(const char *path, std::unique_ptr<byte[]> &data, std::array<OptionalCelSprite, 8> &anim, int width)
 {
 	data = nullptr;
 	data = LoadFileInMem(path);
@@ -2188,7 +2188,7 @@ void Player::UpdatePreviewCelSprite(_cmd_id cmdId, Point point, uint16_t wParam1
 		return;
 
 	LoadPlrGFX(*this, *graphic);
-	std::optional<CelSprite> celSprites = AnimationData[static_cast<size_t>(*graphic)].GetCelSpritesForDirection(dir);
+	OptionalCelSprite celSprites = AnimationData[static_cast<size_t>(*graphic)].GetCelSpritesForDirection(dir);
 	if (celSprites && previewCelSprite != celSprites) {
 		previewCelSprite = celSprites;
 		progressToNextGameTickWhenPreviewWasSet = gfProgressToNextGameTick;
@@ -2343,7 +2343,7 @@ void NewPlrAnim(Player &player, player_graphic graphic, Direction dir, int8_t nu
 {
 	LoadPlrGFX(player, graphic);
 
-	std::optional<CelSprite> celSprite = player.AnimationData[static_cast<size_t>(graphic)].GetCelSpritesForDirection(dir);
+	OptionalCelSprite celSprite = player.AnimationData[static_cast<size_t>(graphic)].GetCelSpritesForDirection(dir);
 
 	float previewShownGameTickFragments = 0.F;
 	if (celSprite == player.previewCelSprite && !player.IsWalking())

Source/player.h

@@ -196,14 +196,14 @@ struct PlayerAnimationData {
 	/**
 	 * @brief CelSprites for the different directions
 	 */
-	std::array<std::optional<CelSprite>, 8> CelSpritesForDirections;
+	std::array<OptionalCelSprite, 8> CelSpritesForDirections;
 	/**
 	 * @brief Raw Data (binary) of the CL2 file.
 	 *        Is referenced from CelSprite in celSpritesForDirections
 	 */
 	std::unique_ptr<byte[]> RawData;
 
-	[[nodiscard]] std::optional<CelSprite> GetCelSpritesForDirection(Direction direction) const
+	[[nodiscard]] OptionalCelSprite GetCelSpritesForDirection(Direction direction) const
 	{
 		return CelSpritesForDirections[static_cast<size_t>(direction)];
 	}
@@ -234,7 +234,7 @@ struct Player {
 	/**
 	 * @brief Contains a optional preview CelSprite that is displayed until the current command is handled by the game logic
 	 */
-	std::optional<CelSprite> previewCelSprite;
+	OptionalCelSprite previewCelSprite;
 	/**
 	 * @brief Contains the progress to next game tick when previewCelSprite was set
 	 */

Source/quests.h

@@ -16,7 +16,6 @@
 #include "panels/info_box.hpp"
 #include "textdat.h"
 #include "utils/attributes.h"
-#include "utils/stdcompat/optional.hpp"
 
 namespace devilution {
 

Source/utils/stdcompat/optional.hpp

@@ -7,6 +7,7 @@
 #include <experimental/optional> // IWYU pragma: export
 #define optional experimental::optional
 #define nullopt experimental::nullopt
+#define nullopt_t experimental::nullopt_t
 #else
 #error "Missing support for <optional> or <experimental/optional>"
 #endif