private ITimeline BakeAnimation(AvatarAnimation avatarAnimation)
{
// Create an AvatarExpression key frame animation that will be applied to the Expression
// property of an AvatarPose.
AvatarExpressionKeyFrameAnimation expressionAnimation = new AvatarExpressionKeyFrameAnimation
{
TargetProperty = "Expression"
};
// Create a SkeletonPose key frame animation that will be applied to the SkeletonPose
// property of an AvatarPose.
SkeletonKeyFrameAnimation skeletonKeyFrameAnimation = new SkeletonKeyFrameAnimation
{
TargetProperty = "SkeletonPose"
};
// In the next loop, we sample the original animation with 30 Hz and store the key frames.
int numberOfKeyFrames = 0;
AvatarExpression previousExpression = new AvatarExpression();
TimeSpan time = TimeSpan.Zero;
TimeSpan length = avatarAnimation.Length;
TimeSpan step = new TimeSpan(333333); // 1/30 seconds;
while (true)
{
// Advance time in AvatarAnimation.
avatarAnimation.CurrentPosition = time;
// Add expression key frame if this is the first key frame or if the key frame is
// different from the last key frame.
AvatarExpression expression = avatarAnimation.Expression;
if (time == TimeSpan.Zero || !expression.Equals(previousExpression))
expressionAnimation.KeyFrames.Add(new KeyFrame<AvatarExpression>(time, expression));
previousExpression = expression;
// Convert bone transforms to SrtTransforms and add key frames to the SkeletonPose
// animation.
for (int i = 0; i < avatarAnimation.BoneTransforms.Count; i++)
{
SrtTransform boneTransform = SrtTransform.FromMatrix(avatarAnimation.BoneTransforms[i]);
skeletonKeyFrameAnimation.AddKeyFrame(i, time, boneTransform);
numberOfKeyFrames++;
}
// Abort if we have arrived at the end time.
if (time == length)
break;
// Increase time. We check that we do not step over the end time.
if (time + step > length)
time = length;
else
time += step;
}
// Compress animation to save memory.
float numberOfRemovedKeyFrames = skeletonKeyFrameAnimation.Compress(0.1f, 0.1f, 0.001f);
Debug.WriteLine("Compression removed " + numberOfRemovedKeyFrames * 100 + "% of the key frames.");
// Finalize the skeleton key frame animation. This optimizes the internal data structures.
skeletonKeyFrameAnimation.Freeze();
return new TimelineGroup
{
expressionAnimation,
skeletonKeyFrameAnimation,
};
}
/// <summary>
/// Converts an AnimationContent to a SkeletonKeyFrameAnimation.
/// </summary>
private SkeletonKeyFrameAnimation ProcessAnimation(AnimationContent animationContent, Skeleton skeleton, ContentProcessorContext context)
{
var animation = new SkeletonKeyFrameAnimation { EnableInterpolation = true };
// Process all animation channels (each channel animates a bone).
int numberOfKeyFrames = 0;
foreach (var item in animationContent.Channels)
{
string channelName = item.Key;
AnimationChannel channel = item.Value;
int boneIndex = skeleton.GetIndex(channelName);
if (boneIndex == -1)
{
var message = string.Format("Found animation for bone '{0}', which is not part of the skeleton.", channelName);
throw new InvalidContentException(message, animationContent.Identity);
}
var bindPoseRelativeInverse = skeleton.GetBindPoseRelative(boneIndex).Inverse;
foreach (AnimationKeyframe keyframe in channel)
{
TimeSpan time = keyframe.Time;
SrtTransform transform = SrtTransform.FromMatrix(keyframe.Transform);
// The matrix in the key frame is the transformation in the coordinate space of the
// parent bone. --> Convert it to a transformation relative to the animated bone.
transform = bindPoseRelativeInverse * transform;
// To start with minimal numerical errors, we normalize the rotation quaternion.
transform.Rotation.Normalize();
animation.AddKeyFrame(boneIndex, time, transform);
numberOfKeyFrames++;
}
}
if (numberOfKeyFrames == 0)
throw new InvalidContentException("Animation has no keyframes.", animationContent.Identity);
// Compress animation to safe memory.
float removedKeyFrames = animation.Compress(
CompressionScaleThreshold,
CompressionRotationThreshold,
CompressionTranslationThreshold);
if (removedKeyFrames > 0)
context.Logger.LogImportantMessage("{0}: Compression removed {1:P} of all key frames.",
animationContent.Name,
removedKeyFrames);
// Finalize the animation. (Optimizes the animation data for fast runtime access.)
animation.Freeze();
return animation;
}
private SkeletonKeyFrameAnimation BuildAnimation(AnimationContent animationContent)
{
string name = animationContent.Name;
// Add loop frame?
bool addLoopFrame = false;
if (_modelDescription != null)
{
var animationDescription = _modelDescription.Animation;
if (animationDescription != null)
{
addLoopFrame = animationDescription.AddLoopFrame ?? false;
if (animationDescription.Splits != null)
{
foreach (var split in animationDescription.Splits)
{
if (split.Name == name)
{
if (split.AddLoopFrame.HasValue)
addLoopFrame = split.AddLoopFrame.Value;
break;
}
}
}
}
}
var animation = new SkeletonKeyFrameAnimation { EnableInterpolation = true };
// Process all animation channels (each channel animates a bone).
int numberOfKeyFrames = 0;
foreach (var item in animationContent.Channels)
{
string channelName = item.Key;
AnimationChannel channel = item.Value;
int boneIndex = _skeleton.GetIndex(channelName);
if (boneIndex != -1)
{
SrtTransform? loopFrame = null;
var bindPoseRelativeInverse = _skeleton.GetBindPoseRelative(boneIndex).Inverse;
foreach (AnimationKeyframe keyframe in channel)
{
TimeSpan time = keyframe.Time;
SrtTransform transform = SrtTransform.FromMatrix(keyframe.Transform);
// The matrix in the key frame is the transformation in the coordinate space of the
// parent bone. --> Convert it to a transformation relative to the animated bone.
transform = bindPoseRelativeInverse * transform;
// To start with minimal numerical errors, we normalize the rotation quaternion.
transform.Rotation.Normalize();
if (loopFrame == null)
loopFrame = transform;
if (!addLoopFrame || time < animationContent.Duration)
animation.AddKeyFrame(boneIndex, time, transform);
numberOfKeyFrames++;
}
if (addLoopFrame && loopFrame.HasValue)
animation.AddKeyFrame(boneIndex, animationContent.Duration, loopFrame.Value);
}
else
{
_context.Logger.LogWarning(
null, animationContent.Identity,
"Found animation for bone \"{0}\", which is not part of the skeleton.",
channelName);
}
}
if (numberOfKeyFrames == 0)
{
_context.Logger.LogWarning(null, animationContent.Identity, "Animation is ignored because it has no keyframes.");
return null;
}
// Compress animation to save memory.
if (_modelDescription != null)
{
var animationDescription = _modelDescription.Animation;
if (animationDescription != null)
{
float removedKeyFrames = animation.Compress(
animationDescription.ScaleCompression,
animationDescription.RotationCompression,
animationDescription.TranslationCompression);
if (removedKeyFrames > 0)
{
_context.Logger.LogImportantMessage("{0}: Compression removed {1:P} of all key frames.",
string.IsNullOrEmpty(name) ? "Unnamed" : name,
removedKeyFrames);
}
}
}
// Finalize the animation. (Optimizes the animation data for fast runtime access.)
animation.Freeze();
return animation;
}