POC frame interpolation

FModel/Views/Snooper/Animations/Animation.cs

@@ -24,6 +24,8 @@ public class Animation : IDisposable
 
     public int CurrentSequence;
     public int FrameInSequence;                     // Current Sequence's Frame to Display
+    public int NextFrameInSequence;
+    public float LerpAmount;
 
     public string Label =>
         $"Retarget: {TargetSkeleton}\nSequences: {CurrentSequence + 1}/{Sequences.Length}\nFrames: {FrameInSequence}/{Sequences[CurrentSequence].EndFrame}";
@@ -80,12 +82,17 @@ public class Animation : IDisposable
         for (int s = 0; s < CurrentSequence; s++)
             lastEndTime = Sequences[s].EndTime;
 
-        FrameInSequence = Math.Min(((elapsedTime - lastEndTime) / Sequences[CurrentSequence].TimePerFrame).FloorToInt(), Sequences[CurrentSequence].EndFrame);
+        var exactFrameAtThisTime = (elapsedTime - lastEndTime) / Sequences[CurrentSequence].TimePerFrame;
+        FrameInSequence = Math.Min(exactFrameAtThisTime.FloorToInt(), Sequences[CurrentSequence].EndFrame);
+        NextFrameInSequence = Math.Min(FrameInSequence + 1, Sequences[CurrentSequence].EndFrame);
+        LerpAmount = Math.Clamp(exactFrameAtThisTime - FrameInSequence, 0, 1);
     }
 
     private void Reset()
     {
         FrameInSequence = 0;
+        NextFrameInSequence = 0;
+        LerpAmount = 0.0f;
         CurrentSequence = 0;
     }
 

FModel/Views/Snooper/Animations/Skeleton.cs

@@ -18,8 +18,6 @@ public class Skeleton : IDisposable
     public string Name;
     public readonly Dictionary<string, Bone> BonesByLoweredName;
 
-    private int _previousAnimationSequence;
-    private int _previousSequenceFrame;
     private Transform[][][] _animatedBonesTransform;        // [sequence][bone][frame]
     private readonly Matrix4x4[] _invertedBonesMatrix;
     public int BoneCount => _invertedBonesMatrix.Length;
@@ -210,26 +208,23 @@ public class Skeleton : IDisposable
         _ssbo.UpdateRange(BoneCount, Matrix4x4.Identity);
     }
 
-    public void UpdateAnimationMatrices(int currentSequence, int frameInSequence)
+    public void UpdateAnimationMatrices(int currentSequence, int frameInSequence, int nextFrameInSequence, float lerp)
     {
         if (!IsAnimated) return;
 
-        _previousAnimationSequence = currentSequence;
-        if (_previousSequenceFrame == frameInSequence) return;
-        _previousSequenceFrame = frameInSequence;
-
         _ssbo.Bind();
-        for (int boneIndex = 0; boneIndex < BoneCount; boneIndex++) // interpolate here
-            _ssbo.Update(boneIndex, _invertedBonesMatrix[boneIndex] * _animatedBonesTransform[_previousAnimationSequence][boneIndex][_previousSequenceFrame].Matrix);
+        for (int boneIndex = 0; boneIndex < BoneCount; boneIndex++)
+        {
+            var matrix = Matrix4x4.Lerp(
+                _animatedBonesTransform[currentSequence][boneIndex][frameInSequence].Matrix,
+                _animatedBonesTransform[currentSequence][boneIndex][nextFrameInSequence].Matrix,
+                lerp);
+            _ssbo.Update(boneIndex, _invertedBonesMatrix[boneIndex] * matrix);
+        }
         _ssbo.Unbind();
     }
 
-    public Matrix4x4 GetBoneMatrix(Bone bone)
-    {
-        return IsAnimated
-            ? _animatedBonesTransform[_previousAnimationSequence][bone.Index][_previousSequenceFrame].Matrix
-            : bone.Rest.Matrix;
-    }
+    public Matrix4x4 GetBoneMatrix(Bone bone) => IsAnimated ? bone.Rest.Matrix * _ssbo.Get(bone.Index) : bone.Rest.Matrix;
 
     public void Render()
     {

FModel/Views/Snooper/Buffers/BufferObject.cs

@@ -43,6 +43,17 @@ public class BufferObject<TDataType> : IDisposable where TDataType : unmanaged
         GL.BufferSubData(_bufferTarget, IntPtr.Zero, data.Length * sizeof(TDataType), data);
     }
 
+    public unsafe TDataType Get(int offset)
+    {
+        TDataType data = default;
+
+        Bind();
+        GL.GetBufferSubData(_bufferTarget, (IntPtr) (offset * sizeof(TDataType)), sizeof(TDataType), ref data);
+        Unbind();
+
+        return data;
+    }
+
     public void Bind()
     {
         GL.BindBuffer(_bufferTarget, _handle);

FModel/Views/Snooper/Models/Model.cs

@@ -370,9 +370,17 @@ public class Model : IDisposable
             _vao.Unbind();
         }
 
-        for (int section = 0; section < Sections.Length; section++)
+        if (options.Models.Count == 1 && Sections.All(x => !x.Show))
         {
-            if (!Show) Show = Sections[section].Show;
+            Show = true;
+            foreach (var section in Sections)
+            {
+                section.Show = true;
+            }
+        }
+        else foreach (var section in Sections)
+        {
+            if (!Show) Show = section.Show;
         }
 
         IsSetup = true;

FModel/Views/Snooper/Renderer.cs

@@ -234,7 +234,9 @@ public class Renderer : IDisposable
             animation.TimeCalculation(Options.Tracker.ElapsedTime);
             foreach (var guid in animation.AttachedModels.Where(guid => Options.Models[guid].HasSkeleton))
             {
-                Options.Models[guid].Skeleton.UpdateAnimationMatrices(animation.CurrentSequence, animation.FrameInSequence);
+                Options.Models[guid].Skeleton.UpdateAnimationMatrices(
+                    animation.CurrentSequence, animation.FrameInSequence,
+                    animation.NextFrameInSequence, animation.LerpAmount);
             }
         }