Game Development Reference
In-Depth Information
vehicle, we increment it by the velocity
'
s x and y components and
the deltaTime property.
If you export this example and test it, you
ll notice immediately
the car handles very differently, almost as if it were on ice. When
you turn at high speeds, the car continues in its original direction
for a time before eventually aligning itself with the new direction.
This is because by adding the vectors together with discrete x and
y values, it takes a few passes of friction scaling to reduce the effect
of previous accelerations. Naturally, most cars don
'
tdrifttheway
this one does. With some additional complexity, you could factor
in the weight of the car to determine when the car
'
'
s velocity over-
comes its downward force (essentially, the car
'
straction)andso
Review
We
'
'
ve covered a lot of material in this chapter, so let
s run through
'
a high-level reminder of everything we
ve learned:
￿
The relationship of triangles to angle and distance problems
￿
The trigonometric functions (sine, cosine, and tangent) and
their uses
￿
The coordinate system inside Flash, including the 3D transform
system
￿
How to manipulate objects in Flash
'
s 3D space
￿
How to use perspective projection to create vanishing points
￿
The difference between scalar and vector values in physics
￿
The basics of classical mechanics in motion
velocity, acceleration,
friction, and inertia
￿
How to apply simple 2D physics in ActionScript
￿ How to use the new Vector3D class to simplify the process of
combining vectors
There is considerably more material in topics and on the Inter-