Shows

Shows let you schedule the execution of Cues at various points over the Maestro’s runtime. Using a Show, you can create a list of actions that will automatically play out as the Maestro runs.

Creating a Show

To create a Show, call Maestro::set_show() and pass in an array of Events. To remove a Show, use Maestro::remove_show().

Note

set_show() automatically initializes the CueController if you haven’t already done so, but you’ll still need to enable the necessary CueHandlers before any Events can be processed.

Adding Events

An Event is an object that stores an action to perform (a Cue) and the time that the action will be executed. Events consist of:

• The time when the Event will run (in milliseconds), and

• The Cue that runs when the Event executes.

An Event is executed when the program’s runtime (in milliseconds) matches or exceeds its time. When an Event runs, its Cue is loaded and executed by the Maestro. After an Event executes, the Show automatically moves to the next Event in the queue so that each Event runs sequentially.

You can pass an Event list when creating the Show using Maestro::set_show(). You can also change the Event list mid-show using Show::set_events().

This example creates two Events: one that adds a new Canvas, and one that draws a circle onto the newly created Canvas. Both of these events occur 5 seconds (5000 milliseconds) into the Maestro’s runtime. This means that after 5000 milliseconds, the Show executes the first Event, then immediately executes the second Event.

#include "cue/canvascuehandler.h"
#include "cue/event.h"
#include "cue/sectioncuehandler.h"

// Create 10x10 Maestro
Maestro maestro(10, 10);

// Initialize Event list
int num_events = 2;
Event events[num_events] = {
    Event(5000, section_handler.set_canvas(0, 0)),
    Event(5000, canvas_handler.draw_circle(0, 0, Colors::Green, 5, 5, 2, true))
}

// Initialize the show
Show& show = maestro.set_show(events, num_events);

Timing Modes

The timing mode determines how the Show tracks time between Events. Shows can use one of two timing modes: relative or absolute.

Relative time tracks the amount of time since the last Event executed. For example, if Event 1 has a time of 1000 and Event 2 has a time of 2000 ms, Event 1 executes 1000 ms after the program starts, and Event 2 executes 2000 ms after Event 1.

Absolute time tracks the amount of time since the program started. Using the above example, Event 1 executes 1000 ms after the program starts, and Event 2 executes 2000 ms after the program starts (1000 ms after Event 1 starts).

To set the timing mode, use Show::set_timing_mode().

// Use relative time
show.set_timing_mode(Show::TimingMode::Relative);

Looping

After a Show completes its last Event, it won’t do anything. However, with looping enabled, the Show will jump back to the first event and repeat indefinitely. To enable looping, call Show::set_looping(boolean). To determine whether a Show is looping, call Show::get_looping(). Looping only works when using relative time.