Polarca is the simplest way to use animation curves to interpolate values in game maker studio 2. You just need to create some polarca_animation instances and run it:
//create
xa = new polarca_animation("x",x+400,ac,0,0.005)
polarca_animation_start([xa])
You can also create sequential animation in the simplest way ever! Just pass some arrays of arrays and see the magic happening:
//create
ya = new polarca_animation("image_yscale",8,ac1,1,0.005)
xa = new polarca_animation("image_xscale",8,ac1,0,0.005)
polarca_sequence_start([
[ya],
[xa]
])