求助:如何在spine中动态删除骨骼？

manchangwei

目前在用Spine.Unity开发2D游戏，由于游戏的目标用户大部分是学生党，需要兼容大部分的低端机器，而且之前美术同学在Unity.Spine上没有使用经验，导致现在很多模型都是200根骨骼左右，所以想求助各位大神，有没有Spine的优化方案。
目前想到的方案是不同性能的机器使用不同的Spine模型，但是对于美术来说工作量较大，所以想到的方案是：
美术大大在Spine中编辑的时候，还是按照高端机型来做，但是会在一些骨骼上做特殊处理，比如在骨骼名字后缀加上LQ，代表这根骨骼和它所有的孩子都可以在低端机上删除（这些骨骼主要用来做飘带，锁链等细节）。在加载Spine的时候，会检测带有这些后缀的骨骼名字，然后删除这些骨骼和骨骼相关的动画轨迹。我尝试了一下，直接在Spine编辑器中删除是没有任何问题的，但是在运行的时候，虽然成功删除了和这些LQ骨骼相关的动画轨迹，在Bone.UpdateWorldTransform中屏蔽了这些骨骼的更新，但是停止调用Bone.UpdateWorldTransform会导致在VertexAttachment.ComputeWorldVertices计算顶点数据的时候有错误，导致模型变形。各路大神有没有实现过类似的方案啊，指导一下小弟，感激不尽！
下面是我实现的大概思路：

public class SpineQuality
{
   /// <summary>
   /// 再次限制帧率
   /// </summary>
   public static float updateDelta = -1f;
   /// <summary>
   /// 运行的时候判断是否低端机，如果是，会将useLowerQuality设置true
   /// </summary>
   public static bool useLowerQuality = false;
   /// <summary>
   /// useLowerQuality为true的时候，加载Spine会过滤掉后缀到_LQ的骨骼和他们相关的Timeline
   /// </summary>
   private static string lowerQualitySuffix = "_LQ";
   public static bool IsBoneLowerQuality(string boneName, BoneData parent)
   {
      if (boneName.EndsWith(lowerQualitySuffix))
      {
         return true;
      }
      if (parent != null)
      {
         return IsBoneLowerQuality (parent.name, parent.parent);
      }
      return false;
   }

}

在SkeletonBinary中修改，判断哪些骨骼需要屏蔽

            [code]

public SkeletonData ReadSkeletonData (Stream input) {
if (input == null) throw new ArgumentNullException("input");
float scale = Scale;

     var skeletonData = new SkeletonData();
     skeletonData.hash = ReadString(input);
     if (skeletonData.hash.Length == 0) skeletonData.hash = null;
     skeletonData.version = ReadString(input);
     if (skeletonData.version.Length == 0) skeletonData.version = null;
     skeletonData.width = ReadFloat(input);
     skeletonData.height = ReadFloat(input);

     bool nonessential = ReadBoolean(input);

     if (nonessential) {
        skeletonData.fps = ReadFloat(input);
        skeletonData.imagesPath = ReadString(input);
        if (skeletonData.imagesPath.Length == 0) skeletonData.imagesPath = null;
     }
     ReadBones (input, skeletonData, scale, nonessential);
     // Slots.
     ReadSlots (input, skeletonData);

     // IK constraints.
     ReadIKConstraints (input, skeletonData);

     // Transform constraints.
     ReadTransformConstraints(input, skeletonData, scale);
     // Path constraints
     ReadPathConstraints(input, skeletonData, scale);

     // Default skin.
     Skin defaultSkin = ReadSkin(input, skeletonData, "default", nonessential);
     if (defaultSkin != null) {
        skeletonData.defaultSkin = defaultSkin;
        skeletonData.skins.Add(defaultSkin);
     }

     // Skins.
     for (int i = 0, n = ReadVarint(input, true); i < n; i++)
        skeletonData.skins.Add(ReadSkin(input, skeletonData, ReadString(input), nonessential));

     // Linked meshes.
     for (int i = 0, n = linkedMeshes.Count; i < n; i++) {
        SkeletonJson.LinkedMesh linkedMesh = linkedMeshes[i];
        Skin skin = linkedMesh.skin == null ? skeletonData.DefaultSkin : 
                                          skeletonData.FindSkin(linkedMesh.skin);
        if (skin == null) throw new Exception("Skin not found: " + linkedMesh.skin);
        Attachment parent = skin.GetAttachment(linkedMesh.slotIndex, linkedMesh.parent);
        //if (parent == null) throw new Exception("Parent mesh not found: " + linkedMesh.parent);
        linkedMesh.mesh.ParentMesh = (MeshAttachment)parent;
        linkedMesh.mesh.UpdateUVs();
     }
     linkedMeshes.Clear();

     // Events.
     for (int i = 0, n = ReadVarint(input, true); i < n; i++) {
        EventData data = new EventData(ReadString(input));
        data.Int = ReadVarint(input, false);
        data.Float = ReadFloat(input);
        data.String = ReadString(input);
        skeletonData.events.Add(data);
     }

     // Animations.
     for (int i = 0, n = ReadVarint(input, true); i < n; i++)
        ReadAnimation(ReadString(input), input, skeletonData);

     skeletonData.bones.TrimExcess();
     skeletonData.slots.TrimExcess();
     skeletonData.skins.TrimExcess();
     skeletonData.events.TrimExcess();
     skeletonData.animations.TrimExcess();
     skeletonData.ikConstraints.TrimExcess();
     skeletonData.pathConstraints.TrimExcess();
     return skeletonData;
  }

           private void ReadBones(Stream input, SkeletonData skeletonData, float scale, bool nonessential)
  {
     // Bones.
     for (int i = 0, n = ReadVarint(input, true); i < n; i++) {
        String name = ReadString(input);
        BoneData parent = i == 0 ? null : skeletonData.bones.Items[ReadVarint(input, true)];
        bool isValid = true;
        if (SpineQuality.useLowerQuality)
        {
           if (SpineQuality.IsBoneLowerQuality (name, parent))
           {
              isValid = false;
           }
        }
        //
        BoneData data = new BoneData(i, name, parent);
        data.isValid = isValid;
        data.rotation = ReadFloat(input);      
        data.x = ReadFloat(input) * scale;
        data.y = ReadFloat(input) * scale;
        data.scaleX = ReadFloat(input);
        data.scaleY = ReadFloat(input);
        data.shearX = ReadFloat(input);
        data.shearY = ReadFloat(input);
        data.length = ReadFloat(input) * scale;
        data.transformMode = TransformModeValues[ReadVarint(input, true)];
        if (nonessential) ReadInt(input); // Skip bone color.
        skeletonData.bones.Add(data);
     }
  }

private void ReadAnimation (String name, Stream input, SkeletonData skeletonData)
{
var timelines = new ExposedList<Timeline>();
float scale = Scale;
float duration = 0;

     // Slot timelines.
     ReadSlotTimelines(input, skeletonData, timelines, ref duration);

     // Bone timelines.
     ReadBonesTimelines(input, skeletonData, timelines, scale, ref duration);

     // IK timelines.
     ReadIKsTimelines(input, skeletonData, timelines, ref duration);

     // Transform constraint timelines.
     ReadTransformConstraintsTimelines(input, skeletonData, timelines, ref duration);

     // Path constraint timelines.
     ReadPathConstraintTimelines(input, skeletonData, timelines,scale, ref duration);

     // Deform timelines.
     ReadDeformTimelines(input, skeletonData, timelines,scale, ref duration);
     // Draw order timeline.
     ReadDrawOrderTimelines(input, skeletonData, timelines, ref duration);

     // Event timeline.
     ReadEventTimelines(input, skeletonData, timelines, ref duration);

     timelines.TrimExcess();
     skeletonData.animations.Add(new Animation(name, timelines, duration));
  }

void ReadBonesTimelines(Stream input, SkeletonData skeletonData, ExposedList<Timeline> timelines, float scale, ref float duration)
{
for (int i = 0, n = ReadVarint(input, true); i < n; i++)
{
int boneIndex = ReadVarint(input, true);
BoneData boneData = skeletonData.bones.Items [boneIndex];
for (int ii = 0, nn = ReadVarint(input, true); ii < nn; ii++)
{
int timelineType = input.ReadByte();
int frameCount = ReadVarint(input, true);
switch (timelineType)
{
case BONE_ROTATE:
{
if (true)
{
RotateTimeline timeline = new RotateTimeline(frameCount);
timeline.boneIndex = boneIndex;
for (int frameIndex = 0; frameIndex < frameCount; frameIndex++)
{
timeline.SetFrame(frameIndex, ReadFloat(input), ReadFloat(input));
if (frameIndex < frameCount - 1) ReadCurve(input, frameIndex, timeline);
}
timelines.Add(timeline);
duration = Math.Max(duration, timeline.frames[(frameCount - 1) * RotateTimeline.ENTRIES]);
}
else
{

                    for (int frameIndex = 0; frameIndex < frameCount; frameIndex++) 
                    {
                       ReadFloat (input);
                       ReadFloat (input);
                       if (frameIndex < frameCount - 1) ReadCurve(input, frameIndex, null);
                    }
                 }
                 break;
              }
           case BONE_TRANSLATE:
           case BONE_SCALE:
           case BONE_SHEAR: 
              {
                 if (true) {
                    TranslateTimeline timeline;
                    float timelineScale = 1;
                    if (timelineType == BONE_SCALE)
                       timeline = new ScaleTimeline (frameCount);
                    else if (timelineType == BONE_SHEAR)
                       timeline = new ShearTimeline (frameCount);
                    else {
                       timeline = new TranslateTimeline (frameCount);
                       timelineScale = scale;
                    }
                    timeline.boneIndex = boneIndex;
                    for (int frameIndex = 0; frameIndex < frameCount; frameIndex++) {
                       timeline.SetFrame (frameIndex, ReadFloat (input), ReadFloat (input) * timelineScale, ReadFloat (input)
                       * timelineScale);
                       if (frameIndex < frameCount - 1)
                          ReadCurve (input, frameIndex, timeline);
                    }
                    timelines.Add (timeline);
                    duration = Math.Max (duration, timeline.frames [(frameCount - 1) * TranslateTimeline.ENTRIES]);
                 }
                 else
                 {
                    for (int frameIndex = 0; frameIndex < frameCount; frameIndex++) 
                    {
                       ReadFloat (input);
                       ReadFloat(input);
                       ReadFloat (input);
                       if (frameIndex < frameCount - 1) ReadCurve(input, frameIndex, null);
                    }
                 }
                 break;
              }
           }
        }
     }
  }

[/code]

然后在Skeleton中，创建骨架的时候，屏蔽掉LQ骨骼的更新

public Skeleton (SkeletonData data) {
         if (data == null) throw new ArgumentNullException("data", "data cannot be null.");
         this.data = data;

     bones = new ExposedList<Bone>(data.bones.Count);
     foreach (BoneData boneData in data.bones) {
        Bone bone;
        if (boneData.parent == null) 
        {
           bone = new Bone(boneData, this, null);            
        } 
        else 
        {
           Bone parent = bones.Items[boneData.parent.index];
           bone = new Bone(boneData, this, parent);
           bone.isValid = boneData.isValid;
           if (bone.isValid)
           {
              parent.children.Add(bone);   
           }                  
        }
        bones.Add(bone);         
     }

     slots = new ExposedList<Slot>(data.slots.Count);
     drawOrder = new ExposedList<Slot>(data.slots.Count);
     foreach (SlotData slotData in data.slots) {
        Bone bone = bones.Items[slotData.boneData.index];
        Slot slot = new Slot(slotData, bone);
        slots.Add(slot);
        drawOrder.Add(slot);
     }

     ikConstraints = new ExposedList<IkConstraint>(data.ikConstraints.Count);
     foreach (IkConstraintData ikConstraintData in data.ikConstraints)
        ikConstraints.Add(new IkConstraint(ikConstraintData, this));

     transformConstraints = new ExposedList<TransformConstraint>(data.transformConstraints.Count);
     foreach (TransformConstraintData transformConstraintData in data.transformConstraints)
        transformConstraints.Add(new TransformConstraint(transformConstraintData, this));

     pathConstraints = new ExposedList<PathConstraint> (data.pathConstraints.Count);
     foreach (PathConstraintData pathConstraintData in data.pathConstraints)
        pathConstraints.Add(new PathConstraint(pathConstraintData, this));

     UpdateCache();
     UpdateWorldTransform();
  }

在Bone的Update中直接屏蔽

public void Update () {
         if (isValid == false)
            return;
         UpdateWorldTransform(x, y, rotation, scaleX, scaleY, shearX, shearY);
      }

manchangwei

Harald

我在这看到一个普遍的问题：
如果在某些低质量骨骼上设置“isValid == false”时阻止重新生成世界变换矩阵，则缺少将父变换应用于顶点。
I see a general problem here:
If you prevent the world-transformation matrix from being regenerated when you set isValid == false on some low-quality bones, then you are missing to apply the parent's transformations to the vertices.

请注意，UpdateWorldTransform的文档还指出：
Note that the documentation of UpdateWorldTransform also states:

Computes the world transform using the parent bone and the specified local transform.

您需要的是不更新本地变换，需要更新世界变换。因此，这不会为您节省大量的计算时间，因为您仍然需要应用低质量骨骼的初始设置姿势旋转。
What you would need is to not update the local transform, the world transform needs to be updated. As a consequence, this will not save you a lot of computation time, since you still need to apply the initial setup-pose rotation of the low-quality bone.

所以我们宁愿建议去除Spine中的骨头，这样会产生最好的效果。如果你真的需要以编程方式删除部件，你可以删除动画时间轴 - 但是这不会为你节省很多，因为骨头仍在那里并且需要更新世界变换，如上所述。
So we would rather suggest to either remove the bones in Spine which will have the best effect. If you really need to remove parts programmatically, you could maybe remove animation timelines - however this will not save you a whole lot, as the bones are still there and world-transforms need to be updated, as described above.

manchangwei

谢谢，因为我们美术比较懒，想要程序动态删除，目前删除了时间轴后效率已经差不多了，如果后面在低端机还有效率问题，就只能让美术在Spine里面删除导出来解决。谢谢啦

Harald

别客气。很高兴你能解决这个问题。
You're welcome. Glad you could resolve the problem.