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Video Game Design Foundations
that point exists. If you locate the colored dot on the graph in Figure 4-21, the
coordinates are (5,3) or X = 5 and Y = 3. The same concept of coordinates
applies to game design, except the Y axis is flipped in some game engines.
Figure 4-22 shows an image from The Games Factory 2. This shows a 2D
frame where the origin of the coordinate system (0,0) for the frame start is the
top-left corner. If the pointer moves one pixel to the right along the X axis, the
coordinates are 1,0. If the pointer then moves one pixel down along the Y axis,
the coordinates are 1,1. To find
the total screen size, the pointer
can be moved to the bottom-
right corner. Here, the coordinate
indicator would read 420,680 as
this screen size is 680 pixels wide
and 420 pixels tall.
Also included in the concept
of 2D depth perception is
parallax
movement. To create depth when
a 2D character moves, designers
create a background from multiple
CHEAT CODE: PARALLAX
Parallax describes how objects in the
distance seem to move more slowly
than objects in the foreground. This
creates a slight change of perspective
when the foreground object moves. An easy way to practice
this is to hold one finger up as you point at an object in
the distance. Close one eye at a time and the object in the
distance seems to jump to the other side of your finger.
Figure 4-22.
Clickteam/Goodheart-Willcox Publisher
This is a 2D frame where the origin of the frame’s coordinate system
(0,0) is the top-left corner of the frame.