Animation basics

This C# Intermediate tutorial covers the basics of animation with Stride.

Explanation

All animations exist as animation clips assets in your project. From there on we can start, pause and fade animations by using Stride's animation component.

Code

// Copyright (c) .NET Foundation and Contributors (https://dotnetfoundation.org/ & https://stride3d.net)
// Distributed under the MIT license. See the LICENSE.md file in the project root for more information.
using System;
using Stride.Animations;
using Stride.Core.Mathematics;
using Stride.Engine;
using Stride.Input;

namespace CSharpIntermediate.Code
{
    public class AnimationBasics : SyncScript
    {
        public float AnimationSpeed = 1.0f;
        private AnimationComponent animation;
        private PlayingAnimation latestAnimation;

        public override void Start()
        {
            animation = Entity.Get<AnimationComponent>();

            // Set the default animation
            latestAnimation = animation.Play("Idle");
        }

        public override void Update()
        {
            int drawX = 800, drawY = 600;

            StopOrResumeAnimations(drawX, drawY += 20);

            AdjustAnimationSpeed(drawX, drawY += 20);

            DebugText.Print("I to start playing Idle", new Int2(drawX, drawY += 20));
            if (Input.IsKeyPressed(Keys.I))
            {
                latestAnimation = animation.Play("Idle");
                latestAnimation.TimeFactor = AnimationSpeed;
            }

            DebugText.Print("R to crossfade to Run", new Int2(drawX, drawY += 20));
            if (Input.IsKeyPressed(Keys.R))
            {
                latestAnimation = animation.Crossfade("Run", TimeSpan.FromSeconds(0.5));
                latestAnimation.TimeFactor = AnimationSpeed;
            }

            // We can crossfade to a punch animation, but only if it is not already playing
            DebugText.Print("P to crossfade to Punch and play it once", new Int2(drawX, drawY += 20));
            if (Input.IsKeyPressed(Keys.P) && !animation.IsPlaying("Punch"))
            {
                latestAnimation = animation.Crossfade("Punch", TimeSpan.FromSeconds(0.1));
                latestAnimation.RepeatMode = AnimationRepeatMode.PlayOnce;
                latestAnimation.TimeFactor = AnimationSpeed;
            }

            // When the punch animation is the latest animation, but it is no longer playing, we set a new animation
            if (latestAnimation.Name == "Punch" && !animation.IsPlaying("Punch"))
            {
                latestAnimation = animation.Play("Idle");
                latestAnimation.RepeatMode = AnimationRepeatMode.LoopInfinite;
                latestAnimation.TimeFactor = AnimationSpeed;
            }
        }

        private void StopOrResumeAnimations(int drawX, int drawY)
        {
            DebugText.Print($"S to pause or resume animations", new Int2(drawX, drawY));
            if (Input.IsKeyPressed(Keys.S))
            {
                foreach (var playingAnimation in animation.PlayingAnimations)
                {
                    playingAnimation.Enabled = !playingAnimation.Enabled;
                }
            }
        }

        private void AdjustAnimationSpeed(int drawX, int drawY)
        {
            DebugText.Print($"Q and E for speed {AnimationSpeed:0.0}", new Int2(drawX, drawY));
            if (Input.IsKeyPressed(Keys.E))
            {
                AnimationSpeed += 0.1f;
                latestAnimation.TimeFactor = AnimationSpeed;
            }
            if (Input.IsKeyPressed(Keys.Q))
            {
                AnimationSpeed -= 0.1f;
                latestAnimation.TimeFactor = AnimationSpeed;
            }
        }
    }
}