104 Video Game Design Foundations
After determining the screen dimensions, the designer needs to determine
the gameplay dimensions. The gameplay can be designed as 2D, 2.5D, or 3D.
Two-Dimensional
Games
Two-dimensional (2D) games have
characters and backgrounds that play in only two
dimensions: length and width, Figure 4-14. A
character in a 2D game can only move up, down,
left, or right to the limit of the length and width of
the game frame. This style of game has fl at char-
acters on a fl at background.
There are two terms commonly used to describe the presentation of a 2D
game on the screen: game frame and visible play area. A game frame includes
all of the items programmed for a complete scene or level of a game. The
game frame is the entire game world for that scene. This includes items visible
on screen and all items that exist off screen. The part of a game frame that is
displayed on the video screen is called the visible play area or scope.
The HSL model uses hue, saturation, and
luminescence values to create colors. The hue
value determines which color in the spectrum
shown is the basis, from red to purple. The
saturation level is the amount of hue. In other
words, it is the density of the color. The higher
the saturation, the more of the base color used.
Together the hue and saturation work
like the X and Y coordinates of a number
line. Notice in the fi gure the target site that is
created on the palette by entering a value for
the hue and saturation below. This technique
chooses a color from the palette.
The luminescence setting is how bright
or dark the color appears. The average color
brightness is 112. If luminescence is set to 0,
the color has no luminescence and is black. If
luminescence is set to 255, the color is white.
Values in between result in varying degrees of
the darkness/lightness of the base color.
(Continued)
Target
HSL
values
Color is
orange
In this example, the HSL color model is used to defi ne orange.
THINK ABOUT IT
ACTIVITY 4.2
A computer adds pixels through
interpolation when enlarging an
object. What processes do you
think occur when the computer
reduces the size of an object?