Fighting Talk: The Empower Strikes Back - The Game Maker's Companion: Game Development - page 146

Not So Solid Ground
Falling platforms are another common feature in platform games. In Zool, these resemble static
lifts, but fall away beneath the player's feet a moment or two after the player stands on them. This
keeps the player on their toes and makes sure they keep moving. We'll also make them respawn
after a certain amount of time to give the player another chance at getting through a tricky set of
falling platforms.
Creating Falling Platforms
1. Create a new object ( Platforms , Lifts group) called obj_ledge_fall , give it the
spr_ledge_fall sprite, the obj_ledge Parent , and set Depth to -1001 .
2. Add a Create event and include a Set Variable action ( control tab) that sets falling to
false .
3. Add a Step, Step event and include a Check Object action to check if there would be a
collision with an instance of obj_zool at a Relative position of X = 0 , Y = -16 .
4. Follow this with a Test Variable action that tests if falling is equal to false .
5. Follow this with a Start Block action.
6. Include a Set Variable action that sets falling to true .
7. Include a Set Alarm action ( main2 tab) that sets Alarm 0 to 30 Steps .
8. Include an End Block action ( control tab).
9. Add an Alarm, Alarm 0 event and include a Set Gravity action ( move tab) that sets
Gravity to 3 in Direction 270 .
10. Add an Other, Outside Room event and include a Test Variable action ( control tab)
that tests if falling is equal to true .
11. Include a Start Block action.
12. Include a Set Variable action that sets falling to false .
13. Include a Set Gravity action ( move tab) that sets Gravity to 0 in Direction 270 .
14. Include a Set Variable action ( control tab) that sets speed to 0 . This is another way of
stopping an instance dead.
15. Include a Set Alarm event ( main2 tab) that sets Alarm 1 to 300 Steps .
16. Include an End Block action ( control tab).
17. Add an Alarm, Alarm 1 event and include a Jump to Start action ( move tab).
At this point, you should now be in a position to create the final layout of your test level
including all of the enemies, platforms, and collectibles. You can either take some time to do this
for yourself or load the file zool13.gmk from the Chapter06/Games directory on the CD.