A lightweight and powerful tween/animation system for GameMaker Studio 2 that uses Animation Curves for precise easing control. Provides a fluent API for creating smooth animations with minimal code.

Version: 2.1.0

• Fluent API - Chain methods for intuitive animation setup
• 11 Easing Types - LINEAR, EASE, CUBIC, QUART, EXPO, CIRC, BACK, ELASTIC, BOUNCE, FAST_SLOW, MID_SLOW
• Two Animation Types - Once (single direction) and Patrol (round-trip)
• Tag System - Group and control multiple animations together
• Time Scale Control - Global and per-animation timing adjustments
• Repeat System - Single, multiple, or infinite repetitions
• Reverse Playback - Reverse any animation direction on demand
• Reusable - Refresh and replay animations with new values
• Launch Chain - Queue animations to play sequentially or on specific repeats
• Works with Instances & Structs - Animate any variable on GameMaker instances or custom structs
• Frame-Independent - Uses GameMaker's Time Source system for consistent timing

1. Clone or download this repository
2. Import the '.yymps' file into your GameMaker Studio 2 project

// Create a simple animation
new SCurve("Ease")
    .Target(obj_player)
    .Once(1.5, "x", 500)
    .Play();

new SCurve("Cubic")
    .Target(obj_ui)
    .Once(0.8, "x", 300, "y", 200, "alpha", 0.5)
    .Delay(0.3)
    .OnFinish(function() { show_debug_message("Animation done!"); })
    .Play();

new SCurve("Ease")
    .Target(button)
    .Patrol(0.5, 0.5, 0.2, "scale_x", 1.1, "scale_y", 1.1)
    .Repeat(-1)  // Infinite repeats
    .Play();

Creates a new animation instance.

Parameters:

• curve_name (String) - Name of the Animation Curve to use (e.g., "Ease", "Cubic", "Bounce")
• destroy_on_finish (Bool, optional) - Auto-destroy on finish (default: true)

var anim = new SCurve("Elastic");

Sets the target instance or struct to animate.

new SCurve("Linear").Target(my_instance).Play();

Configures a single-direction animation.

Parameters:

• duration (Real) - Animation duration in seconds
• prop_name (String) - Variable name to animate
• end_value (Real/String) - Final value (supports relative syntax: "+100", "-50", "*2", "/2")

.Once(2.0, "x", 500, "y", "+300")

Configures a round-trip animation.

Parameters:

• duration_go (Real) - Forward phase duration in seconds
• duration_back (Real) - Return phase duration in seconds
• delay (Real) - Wait time between phases in seconds
• prop_name (String) - Variable name to animate
• end_value (Real/String) - Value at end of forward phase

.Patrol(1.0, 1.0, 0.5, "x", 200)

(Patrol only) Optionally set different return values for properties.

.Patrol(1.0, 1.0, 0, "y", 300)
.ReturningTo("y", 100)  // Returns to 100 instead of starting position

Sets initial delay before animation starts.

.Delay(0.5)

Sets animation speed multiplier (1.0 = normal, 0.5 = half speed, 2.0 = double speed).

.TimeScale(0.8)

Sets number of repetitions (-1 for infinite).

.Repeat(3)      // Repeat 3 times
.Repeat(-1)     // Infinite loop

Starts the animation.

new SCurve("Ease").Target(obj).Once(1, "x", 100).Play();

Pauses the animation.

anim.Pause();

Resumes a paused animation.

anim.Resume();

Stops the animation and resets timing.

anim.Stop();

Recaptures initial property values from target. Useful for reusable animations.

anim.Refresh().Play();

Cleans up animation resources.

anim.Destroy();

(Once only) Reverses animation direction.

.Once(1.0, "x", 500)
.Reverse(true)   // Animates from 500 back to original value
.Play();

Executes when animation completes.

.OnFinish(function() { show_debug_message("Done!"); })

Executes on each repeat completion (receives repeat count as parameter).

.OnRepeat(function(repeat_num) { 
    show_debug_message("Repeat " + string(repeat_num)); 
})

Executes when initial delay completes.

.OnDelayFinish(function() { show_debug_message("Delay over"); })

(Patrol only) Executes when forward phase completes.

.OnContinue(function() { show_debug_message("Reached target"); })

(Patrol only) Executes when wait phase completes.

.OnWait(function() { show_debug_message("Starting return"); })

Launches another animation at the end or on specific repeat.

var anim1 = new SCurve("Ease").Target(obj).Once(1, "x", 100);
var anim2 = new SCurve("Ease").Target(obj).Once(1, "y", 200);

anim1.Launch(anim2).Play();  // anim2 plays after anim1

Controls auto-destruction behavior.

.DestroyOnFinish(false)  // Keep animation instance after finish

Assigns one or more tags for group control.

.Tag("ui", "menu")

Checks if animation has a specific tag.

if (anim.HasTag("ui")) { /* ... */ }

Returns true if animation is actively running.

if (anim.IsPlaying()) { show_debug_message("Running"); }

Returns true if animation is paused.

if (anim.IsPaused()) { anim.Resume(); }

Returns true if animation has stopped or completed.

if (anim.IsFinished()) { show_debug_message("Complete"); }

Returns true if currently in delay phase.

if (anim.IsDelaying()) { /* ... */ }

Returns true if animation is configured to play in reverse.

if (anim.IsReversed()) { /* ... */ }

Returns animation type ("once" or "patrol").

var type = anim.GetType();

(Patrol only) Returns current phase ("go", "wait", or "back").

if (anim.GetPatrolState() == "back") { /* ... */ }

Returns normalized progress (0-1) of current phase.

var progress = anim.GetProgress();

Returns number of completed repeats.

show_debug_message("Repeats done: " + string(anim.GetRepeatCount()));

Pauses all active animations.

SCMaster.PauseAll();

Resumes all paused animations.

SCMaster.ResumeAll();

Sets global time scale for all animations.

SCMaster.SetGlobalTimeScale(0.5);  // Slow-motion effect

Gets current global time scale.

var scale = SCMaster.GetGlobalTimeScale();

Pauses all animations with a specific tag.

SCMaster.PauseTag("ui");

Resumes animations with a specific tag.

SCMaster.ResumeTag("ui");

Stops all animations with a specific tag.

SCMaster.StopTag("effects");

Destroys all animations with a specific tag.

SCMaster.DestroyTag("temp");

Sets time scale for animations with a specific tag.

SCMaster.SetTimeScaleByTag("ui", 1.5);  // UI animations 50% faster

Launches multiple animations with staggered delays.

SCMaster.StaggerLaunch(0.1, anim1, anim2, anim3);  // 0.1s between each

Simple Curves includes 11 easing presets:

new SCurve("Ease")
    .Target(player)
    .Once(1.0, "x", "+100", "y", "-50")  // +100 pixels right, -50 down
    .Play();

var fade_out = new SCurve("Ease")
    .Target(ui_element)
    .Once(0.5, "alpha", 0);

var move = new SCurve("Cubic")
    .Target(ui_element)
    .Once(1.0, "x", 800);

fade_out.Launch(move).Play();

new SCurve("Bounce")
    .Target(obj_ball)
    .Patrol(0.5, 0.5, 0, "y", "-100")
    .Repeat(-1)
    .OnContinue(function() { play_sound(snd_bounce); })
    .Play();

function create_pulse_animation(target) {
    return new SCurve("Ease")
        .Target(target)
        .Patrol(0.2, 0.2, 0, "scale_x", 1.2, "scale_y", 1.2)
        .Repeat(1)
        .DestroyOnFinish(false);
}

// Reuse multiple times
var pulse = create_pulse_animation(button1);
pulse.Play();
// Later...
pulse.Refresh().Play();

// Create multiple UI animations with tags
new SCurve("Ease").Target(btn1).Once(0.5, "alpha", 0).Tag("ui", "menu").Play();
new SCurve("Ease").Target(btn2).Once(0.5, "alpha", 0).Tag("ui", "menu").Play();
new SCurve("Ease").Target(btn3).Once(0.5, "alpha", 0).Tag("ui", "menu").Play();

// Control them all at once
SCMaster.PauseTag("menu");      // Pause all
SCMaster.ResumeTag("menu");     // Resume all
SCMaster.SetTimeScaleByTag("menu", 0.5);  // Slow down menu animations

// Pause game logic but keep animations at slower speed
SCMaster.SetGlobalTimeScale(0.3);

// Later, resume normal speed
SCMaster.SetGlobalTimeScale(1.0);

• Simple Curves uses GameMaker's Time Source system for frame-independent timing
• Delta time is clamped to maintain smooth animation during frame drops
• Animations are automatically unregistered from the global manager when destroyed
• Use tags to efficiently manage groups of animations
• The library handles both instances and structs, adapting to the target type

Example usage is demonstrated in o_iamfade object:

• Creates a reversible animation on struct animation data
• Press spacebar to reverse/toggle animation direction
• Shows how to use callbacks and state queries

See LICENSE file for details.