Designing Games with Game Maker - YoYo Games

As you should know, every instance has 12 different alarm clocks that you can set. To change
the values (or get the values) of the different alarm clocks use the following variable:
alarm[0..11] Value of the indicated alarm clock. (Note that alarm clocks
only get updated when the alarm event for the object contains actions!)
We have seen that for complex timing issues you can use the time line resource. Each
instance can have a time line resource associated with it. The following variables deal with
this:
Rooms
timeline_index Index of the time line associated with the instance. You can
set this to a particular time line to use that one. Set it to -1 to stop using a
time line for the instance.
timeline_position Current position within the time line. You can change
this to skip certain parts or to repeat parts.
timeline_speed Normally, in each step the position in the time line is
increased by 1. You can change this amount by setting this variable to a
different value. You can use real numbers like 0.5. If the value is larger than
one, several moments can happen within the same time step. They will all be
performed in the correct order, so no actions will be skipped.
Games work in rooms. Each room has an index that is indicated by the name of the room. The
current room is stored in variable room. You cannot assume that rooms are numbered in a
consecutive order. So never add or subtract a number from the room variable. Instead use the
functions and variables indicated below. So a typical piece of code you will use is:
{
if (room != room_last)
{
}
room_goto_next();
else
{
game_end();