OpenTTD/src/newgrf_object.h

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file newgrf_object.h Functions related to NewGRF objects. */

#ifndef NEWGRF_OBJECT_H
#define NEWGRF_OBJECT_H

#include "newgrf_callbacks.h"
#include "newgrf_spritegroup.h"
#include "newgrf_town.h"
#include "economy_func.h"
#include "timer/timer_game_calendar.h"
#include "object_type.h"
#include "newgrf_animation_type.h"
#include "newgrf_class.h"
#include "newgrf_commons.h"

/** Various object behaviours. */
enum ObjectFlags : uint16_t {
	OBJECT_FLAG_NONE               =       0, ///< Just nothing.
	OBJECT_FLAG_ONLY_IN_SCENEDIT   = 1 <<  0, ///< Object can only be constructed in the scenario editor.
	OBJECT_FLAG_CANNOT_REMOVE      = 1 <<  1, ///< Object can not be removed.
	OBJECT_FLAG_AUTOREMOVE         = 1 <<  2, ///< Object get automatically removed (like "owned land").
	OBJECT_FLAG_BUILT_ON_WATER     = 1 <<  3, ///< Object can be built on water (not required).
	OBJECT_FLAG_CLEAR_INCOME       = 1 <<  4, ///< When object is cleared a positive income is generated instead of a cost.
	OBJECT_FLAG_HAS_NO_FOUNDATION  = 1 <<  5, ///< Do not display foundations when on a slope.
	OBJECT_FLAG_ANIMATION          = 1 <<  6, ///< Object has animated tiles.
	OBJECT_FLAG_ONLY_IN_GAME       = 1 <<  7, ///< Object can only be built in game.
	OBJECT_FLAG_2CC_COLOUR         = 1 <<  8, ///< Object wants 2CC colour mapping.
	OBJECT_FLAG_NOT_ON_LAND        = 1 <<  9, ///< Object can not be on land, implicitly sets #OBJECT_FLAG_BUILT_ON_WATER.
	OBJECT_FLAG_DRAW_WATER         = 1 << 10, ///< Object wants to be drawn on water.
	OBJECT_FLAG_ALLOW_UNDER_BRIDGE = 1 << 11, ///< Object can built under a bridge.
	OBJECT_FLAG_ANIM_RANDOM_BITS   = 1 << 12, ///< Object wants random bits in "next animation frame" callback.
	OBJECT_FLAG_SCALE_BY_WATER     = 1 << 13, ///< Object count is roughly scaled by water amount at edges.
};
DECLARE_ENUM_AS_BIT_SET(ObjectFlags)

static const uint8_t OBJECT_SIZE_1X1 = 0x11; ///< The value of a NewGRF's size property when the object is 1x1 tiles: low nibble for X, high nibble for Y.

void ResetObjects();

/** Class IDs for objects. */
enum ObjectClassID : uint16_t {
	OBJECT_CLASS_BEGIN = 0, ///< The lowest valid value
	OBJECT_CLASS_MAX = UINT16_MAX, ///< Maximum number of classes.
	INVALID_OBJECT_CLASS = UINT16_MAX, ///< Class for the less fortunate.
};
/** Allow incrementing of ObjectClassID variables */
DECLARE_POSTFIX_INCREMENT(ObjectClassID)

/** An object that isn't use for transport, industries or houses.
 * @note If you change this struct, adopt the initialization of
 * default objects in table/object_land.h
 */
struct ObjectSpec {
	/* 2 because of the "normal" and "buy" sprite stacks. */
	GRFFilePropsBase<2> grf_prop; ///< Properties related the the grf file
	AnimationInfo animation;      ///< Information about the animation.
	ObjectClassID cls_id;         ///< The class to which this spec belongs.
	StringID name;                ///< The name for this object.

	uint8_t climate;                ///< In which climates is this object available?
	uint8_t size;                   ///< The size of this objects; low nibble for X, high nibble for Y.
	uint8_t build_cost_multiplier;  ///< Build cost multiplier per tile.
	uint8_t clear_cost_multiplier;  ///< Clear cost multiplier per tile.
	TimerGameCalendar::Date introduction_date; ///< From when can this object be built.
	TimerGameCalendar::Date end_of_life_date;  ///< When can't this object be built anymore.
	ObjectFlags flags;            ///< Flags/settings related to the object.
	uint16_t callback_mask;         ///< Bitmask of requested/allowed callbacks.
	uint8_t height;                 ///< The height of this structure, in heightlevels; max MAX_TILE_HEIGHT.
	uint8_t views;                  ///< The number of views.
	uint8_t generate_amount;        ///< Number of objects which are attempted to be generated per 256^2 map during world generation.

	/**
	 * Test if this object is enabled.
	 * @return True iff this object is enabled.
	 */
	bool IsEnabled() const { return this->views > 0; }

	/**
	 * Get the cost for building a structure of this type.
	 * @return The cost for building.
	 */
	Money GetBuildCost() const { return GetPrice(PR_BUILD_OBJECT, this->build_cost_multiplier, this->grf_prop.grffile, 0); }

	/**
	 * Get the cost for clearing a structure of this type.
	 * @return The cost for clearing.
	 */
	Money GetClearCost() const { return GetPrice(PR_CLEAR_OBJECT, this->clear_cost_multiplier, this->grf_prop.grffile, 0); }

	bool IsEverAvailable() const;
	bool WasEverAvailable() const;
	bool IsAvailable() const;
	uint Index() const;

	static const std::vector<ObjectSpec> &Specs();
	static size_t Count();
	static const ObjectSpec *Get(ObjectType index);
	static const ObjectSpec *GetByTile(TileIndex tile);

	static void BindToClasses();
};

/** Object scope resolver. */
struct ObjectScopeResolver : public ScopeResolver {
	struct Object *obj;     ///< The object the callback is ran for.
	const ObjectSpec *spec; ///< Specification of the object type.
	TileIndex tile;         ///< The tile related to the object.
	uint8_t view;             ///< The view of the object.

	/**
	 * Constructor of an object scope resolver.
	 * @param ro Surrounding resolver.
	 * @param obj Object being resolved.
	 * @param tile %Tile of the object.
	 * @param view View of the object.
	 */
	ObjectScopeResolver(ResolverObject &ro, Object *obj, const ObjectSpec *spec, TileIndex tile, uint8_t view = 0)
		: ScopeResolver(ro), obj(obj), spec(spec), tile(tile), view(view)
	{
	}

	uint32_t GetRandomBits() const override;
	uint32_t GetVariable(uint8_t variable, [[maybe_unused]] uint32_t parameter, bool *available) const override;
};

/** A resolver object to be used with feature 0F spritegroups. */
struct ObjectResolverObject : public ResolverObject {
	ObjectScopeResolver object_scope; ///< The object scope resolver.
	std::optional<TownScopeResolver> town_scope = std::nullopt; ///< The town scope resolver (created on the first call).

	ObjectResolverObject(const ObjectSpec *spec, Object *o, TileIndex tile, uint8_t view = 0,
			CallbackID callback = CBID_NO_CALLBACK, uint32_t param1 = 0, uint32_t param2 = 0);

	ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, uint8_t relative = 0) override
	{
		switch (scope) {
			case VSG_SCOPE_SELF:
				return &this->object_scope;

			case VSG_SCOPE_PARENT: {
				TownScopeResolver *tsr = this->GetTown();
				if (tsr != nullptr) return tsr;
				[[fallthrough]];
			}

			default:
				return ResolverObject::GetScope(scope, relative);
		}
	}

	GrfSpecFeature GetFeature() const override;
	uint32_t GetDebugID() const override;

private:
	TownScopeResolver *GetTown();
};

/** Class containing information relating to object classes. */
using ObjectClass = NewGRFClass<ObjectSpec, ObjectClassID, OBJECT_CLASS_MAX>;

static const size_t OBJECT_SPRITE_GROUP_DEFAULT = 0;
static const size_t OBJECT_SPRITE_GROUP_PURCHASE = 1;

uint16_t GetObjectCallback(CallbackID callback, uint32_t param1, uint32_t param2, const ObjectSpec *spec, Object *o, TileIndex tile, uint8_t view = 0);

void DrawNewObjectTile(TileInfo *ti, const ObjectSpec *spec);
void DrawNewObjectTileInGUI(int x, int y, const ObjectSpec *spec, uint8_t view);
void AnimateNewObjectTile(TileIndex tile);
void TriggerObjectTileAnimation(Object *o, TileIndex tile, ObjectAnimationTrigger trigger, const ObjectSpec *spec);
void TriggerObjectAnimation(Object *o, ObjectAnimationTrigger trigger, const ObjectSpec *spec);

#endif /* NEWGRF_OBJECT_H */