tooll3--t3/Editor/Gui/Interaction/Animation/AnimationOperations.cs

using T3.Core.Animation;
using T3.Core.DataTypes;
using T3.Core.Operator;
using T3.Editor.Gui.Interaction.WithCurves;
using T3.Editor.Gui.Windows.TimeLine;
using T3.Editor.UiModel.Commands;
using T3.Editor.UiModel.Commands.Animation;

namespace T3.Editor.Gui.Interaction.Animation;

internal class AnimationOperations
{
    public static List<VDefinition> InsertKeyframeToCurves(IEnumerable<Curve> curves, double time, float increment = 0)
    {
        var commands = new List<ICommand>();
            
        var newKeyframes = new List<VDefinition>(4);
        foreach (var curve in curves)
        {
            var value = curve.GetSampledValue(time);

            var newKey =  curve.TryGetPreviousKey(time, out var foundKey) 
                              ? foundKey.Clone() 
                              : new VDefinition();


            newKey.Value = value + increment;
            newKey.U = time;

            var command = new AddKeyframesCommand(curve, newKey);
            command.Do();
            commands.Add(command);
            newKeyframes.Add(newKey);
        }
            
        var marcoCommand = new MacroCommand("Insert Keyframe", commands);
        UndoRedoStack.Add(marcoCommand);
            
        return newKeyframes;
    }

    public static void RemoveKeyframeFromCurves(IEnumerable<Curve> curves, double time)
    {
        var commands = new List<ICommand>();
        foreach (var curve in curves)
        {
            var key = curve.GetV(time);
            if (key != null)
            {
                var command = new DeleteKeyframeCommand(curve, key);
                commands.Add(command);
            }
        }
        UndoRedoStack.AddAndExecute(new MacroCommand("Delete keyframes", commands));
    }

    public static void DeleteSelectedKeyframesFromAnimationParameters(VersionedKeyframeSet selectedKeyframes,
                                                                      IEnumerable<TimeLineCanvas.AnimationParameter> animationParameters,
                                                                      Instance compositionOp)
    {
        var commands = new List<ICommand>();
        var selectKeyframesForCurve = new List<VDefinition>();
            
        foreach (var param in animationParameters)
        {
            foreach (var curve in param.Curves)
            {
                selectKeyframesForCurve.Clear();
                //var allSelected = true;
                var vDefinitions = curve.GetVDefinitions().ToList();
                foreach (var keyframe in vDefinitions)
                {
                    if (!selectedKeyframes.Contains(keyframe))
                    {
                        continue;
                    }
                    selectKeyframesForCurve.Add(keyframe);
                }

                var allSelected = selectKeyframesForCurve.Count == vDefinitions.Count;
                if (allSelected)
                {
                    commands.Add(new RemoveAnimationsCommand(compositionOp.Symbol.Animator, new []{param.Input} ));
                }
                else
                {
                    foreach (var keyframe in selectKeyframesForCurve)
                    {
                        commands.Add(new DeleteKeyframeCommand(curve, keyframe, true));
                        selectedKeyframes.Remove(keyframe);
                    }
                }

            }
        }
            
        UndoRedoStack.AddAndExecute(new MacroCommand("Delete keyframes", commands));
    }
}