Game Development Reference
In-Depth Information
Enemy Ammo moves down, but Spaceship Ammo moves up. Also, Enemy Ammo can hit the
Spaceship and Spaceship Shield sprites, but Spaceship Ammo can hit enemy sprites. More
interesingly, Enemy Ammo, contrary to Spaceship Ammo, is level-aware: it changes the
costume based on the current game level. Due to the similarity between Enemy Ammo and
Spaceship Ammo, the Enemy Ammo scripts are included in the starter project.
Engage thrusters
When the game starts, the Spaceship Ammo sprite will only iniialize its variables but not
paricipate in the game yet.
To create the code to iniialize upon receiving the
game_start
message, perform the
following steps:
1.
Start with the
when I receive <game_start>
block.
2.
Use
set <speed> to ()
; fill in the value
100
.
3.
Use
set <power_boost_on> to ()
; fill in the value
false
.
The final script should look like the following screenshot:
The following steps create the code for each Spaceship Ammo clone:
1.
Start with
when I start as a clone
.
2.
Add the
go to <Spaceship>
block.
3.
Then add the
go to front
and
show
blocks.
4.
Add a bit of zest with
play sound <laser>
.
5.
Add an
if () then () else
condiion block to check whether the
power_boost_on
condiion is
true
.
6.
If
power_boost_on
is
true
, this ammo can destroy muliple enemies. So it uses the
change y by (<speed> * <frame_rate>)
and
repeat unil <y posiion> is greater than
() blocks; fill in the value
180
in the
repeat unil
block.
