private void InterpolateKeys(double animationTime, AnimationLayer layer, ref Quaternion rotation, ref Vector3 translation, ref Vector3 scale, PRSKey prsKey, PRSKey nextPrsKey)
{
var nextTime = (nextPrsKey.Time < prsKey.Time
? (nextPrsKey.Time + Animation.Duration)
: nextPrsKey.Time);
var blend = ( float )(animationTime / nextTime);
if (prsKey.HasRotation)
{
rotation = Quaternion.Slerp(prsKey.Rotation, nextPrsKey.Rotation, blend);
}
if (prsKey.HasPosition)
{
translation = Vector3.Lerp(prsKey.Position * layer.PositionScale,
nextPrsKey.Position * layer.PositionScale,
blend);
}
if (prsKey.HasScale)
{
scale = Vector3.Lerp(prsKey.Scale * layer.ScaleScale,
nextPrsKey.Scale * layer.ScaleScale,
blend);
}
}
public static Animation ConvertFromAssimpScene(Ai.Scene aiScene, Ai.Animation aiAnimation, AnimationConverterOptions options)
{
var animation = new Animation(options.Version);
animation.Duration = ConvertTime(aiAnimation.DurationInTicks, aiAnimation.TicksPerSecond);
foreach (var aiChannel in aiAnimation.NodeAnimationChannels)
{
if (AssimpConverterCommon.MeshAttachmentNameRegex.IsMatch(aiChannel.NodeName))
{
continue;
}
var nodeName = AssimpConverterCommon.UnescapeName(aiChannel.NodeName);
Ai.Node node = aiScene.RootNode.FindNode(nodeName);
if (node == null)
{
continue;
}
var controller = new AnimationController(options.Version)
{
TargetKind = TargetKind.Node,
TargetName = nodeName,
TargetId = GetTargetIdForNode(aiScene.RootNode, nodeName)
};
var layer = new AnimationLayer(options.Version);
// NodePRS only for now
layer.KeyType = KeyType.NodePRS;
// Fetch the unique key frame timings from all position, rotation and scale keys.
var aiKeyTimings = aiChannel.PositionKeys
.Select(x => x.Time)
.Concat(aiChannel.RotationKeys.Select(x => x.Time))
.Concat(aiChannel.ScalingKeys.Select(x => x.Time))
.Distinct()
.OrderBy(x => x)
.ToList();
// Decompose the local transform of the affected node so we can use them as the base values for our keyframes
node.Transform.Decompose(out var nodeBaseScale, out var nodeBaseRotation, out var nodeBaseTranslation);
// Keep track of the last position, rotation and scale used to ensure that interpolation works properly
var lastPosition = nodeBaseTranslation;
var lastRotation = nodeBaseRotation;
var lastScale = nodeBaseScale;
for (var i = 0; i < aiKeyTimings.Count; i++)
{
var aiTime = aiKeyTimings[i];
// Start building the keyframe
var key = new PRSKey(layer.KeyType)
{
Position = new Vector3(lastPosition.X, lastPosition.Y, lastPosition.Z),
Rotation = new Quaternion(lastRotation.X, lastRotation.Y, lastRotation.Z, lastRotation.W),
Scale = new Vector3(lastScale.X, lastScale.Y, lastScale.Z)
};
// Fetch the Assimp keys for this time
var aiPositionKey = aiChannel.PositionKeys.SingleOrDefault(x => x.Time == aiTime);
var aiRotationKey = aiChannel.RotationKeys.SingleOrDefault(x => x.Time == aiTime);
var aiScaleKey = aiChannel.ScalingKeys.SingleOrDefault(x => x.Time == aiTime);
if (aiPositionKey != default)
{
key.Position = new Vector3(aiPositionKey.Value.X, aiPositionKey.Value.Y, aiPositionKey.Value.Z);
lastPosition = aiPositionKey.Value;
}
if (aiRotationKey != default)
{
key.Rotation = new Quaternion(aiRotationKey.Value.X, aiRotationKey.Value.Y, aiRotationKey.Value.Z,
aiRotationKey.Value.W);
lastRotation = aiRotationKey.Value;
}
if (aiScaleKey != default)
{
key.Scale = new Vector3(aiScaleKey.Value.X, aiScaleKey.Value.Y, aiScaleKey.Value.Z);
lastScale = aiScaleKey.Value;
}
key.Time = ConvertTime(aiTime, aiAnimation.TicksPerSecond);
layer.Keys.Add(key);
}
controller.Layers.Add(layer);
animation.Controllers.Add(controller);
}
return(animation);
}