Game Development Reference
In-Depth Information
{
textlines.Add(line);
line = fileReader.ReadLine();
}
As you can see, the first time we read a line, we also store the number of characters
in that line, so that we know how many columns our game object grid should have.
Once we have read all the lines, we create the
GameObjectGrid
with the right number
of columns (
width
) and number of rows, which is the same as the number of lines in
the
textlines
list (
textlines.Count
1
):
−
−
1, width, 1, "tiles");
GameObjectGrid tiles =
new
GameObjectGrid(textlines.Count
this
.Add(tiles);
We also set the width and height of each cell in the grid, so that the game object grid
knows where to draw the tiles on the screen:
tiles.CellWidth = 72;
tiles.CellHeight = 55;
Then, we create the
Tile
objects and add them to the
GameObjectGrid
object.
for
(
int
x = 0; x < width; ++x)
for
(
int
y = 0; y < textlines.Count; ++y)
{
Tile t = LoadTile(textlines[y][x], x, y);
tiles.Add(t, x, y);
}
The nested
for
-loop examines all the characters that we read from a file. Just like we
did in
Penguin Pairs
, we use a method called
LoadTile
, which creates a
Tile
object for
us, given a character and the
x
and
y
positions of the tile in the grid.
Inside the
LoadTile
method, we want to load a different tile according to the char-
acter that was passed as a parameter. For each type of tile, we add a method to the
Level
class that creates that particular kind of tile. For example, the
LoadWaterTile
loads a background tile with a water drop on top of it.
All of the methods in the
LevelLoading.cs
file are
private
. This means that only
methods inside the
Level
class can access these methods. Why did we do this? The
reason is that we want to be sure that a level is only loaded when needed. Users
of the
Level
class do not have to call
LoadTiles
or
LoadWaterTile
explicitly. If they
did (by accident hopefully), then the
Level
object might contain invalid information
afterwards. It might contain a different level than what the designer had in mind,
or perhaps some information related to the level, such as the number of water drops
gathered or the time left to finish the game, might no longer be up to date. By making
these methods
private
, we are sure that a level can only be loaded from a file within
the
Level
class itself.
