Это первая статья из серии о создании roguelike 2d-игры.
Мы рассмотрим создание карты или подземелья, как сделать
их динамичными, чтобы при каждом запуске игры карта совершенно другое.
По сути, мы хотим создать случайное количество комнат произвольного размера и соединить их все коридорами.
В итоге получилось так:
(Розовый — это просто цвет фона)
У нас есть две разные плитки: одна для пола и одна для стен комнаты.
Дракон представляет игрока.
Процесс создания подземелья
Алгоритмы основаны на генерации подземелий через BSP-дерево [1].
Процесс происходит следующим образом:
мы начинаем с большой комнаты и делим ее пополам до тех пор, пока мы не сможем больше делить комнату на основе заранее заданного минимального размера для каждой комнаты.
// Some basic structures.
struct Position
{
int32 x;
int32 y;
};
// Sprite is the object that we end up drawing to the screen.
struct Sprite
{
Position position;
int32 height;
int32 width;
SDL_Rect *textCoord;
SDL_Texture *texture;
};
/*
final function to create a dungeon
we run it once at the start of the game.
4000 is the width and height of the whole map.
The other two values are the minimum size of a room.
*/
createDungeon(4000, 4000, dungeonSprites.floorSprite->height * 8, dungeonSprites.floorSprite->width * 8);
struct DungeonCorridor{
Position startPos;
Position endPos;
};
/*
DungeonRoom struct
we need to know how big is the room, where is it positioned
if it has a subRoom and an adjacent(sister) room.
and where is the corridor that connects it to the adjacent room
*/
struct DungeonRoom
{
int32 id;
int32 height;
int32 width;
int32 centerX;
int32 centerY;
DungeonCorridor corridor;
DungeonRoom *subRoom;
DungeonRoom *sisterRoom; // adjacent room
};
/*
dungeonRoomInit allocates a new dungeon room and initializes its values to 0
*/
DungeonRoom *dungeonRoomInit()
{
DungeonRoom *subRoom = (DungeonRoom *)malloc(sizeof(DungeonRoom));
if (subRoom == NULL)
{
return NULL;
}
subRoom->subRoom = NULL;
subRoom->sisterRoom = NULL;
memset(subRoom, 0, sizeof(subRoom));
return subRoom;
}
/*
createSubRooms will recursively generate subrooms until its not posible anymore.
*/
void
createSubRooms(DungeonRoom *masterRoom, uint32 minRoomHeight, uint32 minRoomWidth)
{
/*
because we generate two rooms on every pass of the function, first check
if there is enough space to accomodate two rooms.
*/
if (masterRoom->height > 2 * minRoomHeight && masterRoom->width > 2 * minRoomWidth)
{
DungeonRoom *subRoom1 = dungeonRoomInit();
DungeonRoom *subRoom2 = dungeonRoomInit();
if (subRoom1 == NULL || subRoom2 == NULL)
{
return;
}
/*
we can split a big room either vertically or horizontally.
we accomplish this by selecting a random number between 0 and 100
and decide odd number for vertical, even for horizontal
*/
int directionOfSplit = dungeonRandomizer.distribution.intD(dungeonRandomizer.generator);
int guessTries = 10;
if (directionOfSplit % 2 != 0)
{
/*
Generate rooms with a random width or height base on how we splitted it.
if no valid random value after 10 tries, then just pick the minimum room sizes.
*/
while (guessTries >= 0)
{
auto randomWidth = getRandomInt(minRoomWidth, masterRoom->width);
int pointOfSplit = randomWidth.distribution.intD(randomWidth.generator);
uint32 subRoom1Width = pointOfSplit;
uint32 subRoom2Width = masterRoom->width - pointOfSplit;
if (subRoom1Width < minRoomWidth || subRoom2Width < minRoomWidth)
{
if (guessTries <= 0)
{
subRoom1Width = minRoomWidth;
subRoom2Width = minRoomWidth;
}
else
{
guessTries--;
}
}
else
{
guessTries = -1;
subRoom1->id = masterRoom->id + 1;
subRoom2->id = masterRoom->id + 1;
subRoom1->width = subRoom1Width;
subRoom2->width = subRoom2Width;
subRoom1->height = masterRoom->height;
subRoom2->height = masterRoom->height;
subRoom1->centerX = masterRoom->centerX - subRoom1->width / 2;
subRoom2->centerX = masterRoom->centerX + subRoom2->width / 2;
subRoom1->centerY = masterRoom->centerY;
subRoom2->centerY = masterRoom->centerY;
/*
Select the start and end position of the corridor (currently corridors
are straight so the positions have to be on the same line).
going with the center is therefore a valid approach.
*/
DungeonCorridor corridor = {};
corridor.startPos.x = subRoom1->centerX;
corridor.startPos.y = masterRoom->centerY;
corridor.endPos.x = subRoom2->centerX;
corridor.endPos.y = masterRoom->centerY;
subRoom1->corridor = corridor;
subRoom2->corridor = corridor;
}
}
}
else
{
while (guessTries >= 0)
{
auto randomHeight = getRandomInt(minRoomHeight, masterRoom->height);
int pointOfSplit = randomHeight.distribution.intD(randomHeight.generator);
uint32 subRoom1Height = pointOfSplit;
uint32 subRoom2Height = masterRoom->height - pointOfSplit;
if (subRoom1Height < minRoomHeight || subRoom2Height < minRoomHeight)
{
if (guessTries <= 0)
{
subRoom1Height = minRoomHeight;
subRoom2Height = minRoomHeight;
}
else
{
guessTries--;
}
}
else
{
guessTries = -1;
subRoom1->id = masterRoom->id + 1;
subRoom2->id = masterRoom->id + 1;
subRoom1->height = subRoom1Height;
subRoom2->height = subRoom2Height;
subRoom1->width = masterRoom->width;
subRoom2->width = masterRoom->width;
subRoom1->centerX = masterRoom->centerX;
subRoom2->centerX = masterRoom->centerX;
subRoom1->centerY = masterRoom->centerY - subRoom1->height / 2;
subRoom2->centerY = masterRoom->centerY + subRoom2->height / 2;
DungeonCorridor corridor = {};
corridor.startPos.x = masterRoom->centerX;
corridor.startPos.y = subRoom1->centerY;
corridor.endPos.x = masterRoom->centerX;
corridor.endPos.y = subRoom2->centerY;
subRoom1->corridor = corridor;
subRoom2->corridor = corridor;
}
}
}
subRoom1->sisterRoom = subRoom2;
masterRoom->subRoom = subRoom1;
createSubRooms(subRoom1, minRoomHeight, minRoomWidth);
createSubRooms(subRoom2, minRoomHeight, minRoomWidth);
}
return;
}
DungeonRoom *createDungeon(uint32 height, uint32 width, uint32 minRoomHeight, uint32 minRoomWidth)
{
DungeonRoom *masterRoom = dungeonRoomInit();
masterRoom->id = 0;
masterRoom->height = height;
masterRoom->width = width;
masterRoom->centerX = width / 2;
masterRoom->centerY = height / 2;
masterRoom->sisterRoom = nullptr;
masterRoom->subRoom = nullptr;
// create rooms
createSubRooms(masterRoom, minRoomHeight, minRoomWidth);
return masterRoom;
}
Весь код игры можно найти на github LLschuster/n1 (github.com)[2].
ДЕЛАТЬ:
- Код генерации довольно медленный -› чтобы исправить это, код должен быть профилирован и соответствующим образом рефакторинг ‹Link_TO_Post›
Следующая статья – › WIP
Ссылки:
[1] Базовая генерация BSP Dungeon — RogueBasin
[2] github project
