Added a separate code path for converting frame group animations, and renamed some variables to use the correct frame/pose terminology

Assets/Scripts/Modules/AliasModel.cs

@@ -81,11 +81,20 @@ public class AliasModel
         ConvertUVs(stVertices, header.skinWidth, header.skinHeight, out var uvs);
 
         // Identify animation sequences and turn each one into a separate Mesh with a single blend shape animation
+        if (frameType == QAliasFrameType.Single)
+            ImportSingleFrameAnimations(header, poseVertices, indices, uvs);
+        else
+            ImportGroupFrameAnimations(header, poseVertices, indices, uvs);
+    }
+
+    private void ImportSingleFrameAnimations(QAliasHeader header, QTriVertex[][] poseVertices, ushort[] indices, Vector2[] uvs)
+    {
         Mesh mesh;
         string animName = null;
         int startFrame = 0;
         for (int frameIdx = 0; frameIdx < header.numFrames; ++frameIdx)
         {
+            // Individual sequences are identified by their prefix
             string frameName = AnimationRegex.Match(header.frames[frameIdx].name).Value;
             if (animName == null)
             {
@@ -109,6 +118,18 @@ public class AliasModel
         animationMeshes.Add((startFrame, mesh));
     }
 
+    private void ImportGroupFrameAnimations(QAliasHeader header, QTriVertex[][] poseVertices, ushort[] indices, Vector2[] uvs)
+    {
+        for (int frameIdx = 0; frameIdx < header.numFrames; ++frameIdx)
+        {
+            var frame = header.frames[frameIdx];
+            Mesh mesh = CreateAnimatedMesh(header, poseVertices, indices, uvs, $"{name}_{frameIdx}", 
+                frame.firstPose, frame.firstPose + frame.numPoses);
+            
+            animationMeshes.Add((frame.firstPose, mesh));
+        }
+    }
+    
     /// <summary>
     /// Quake has a bit of a weird outdated mesh setup where skin textures are split into a front side and a back side.
     /// Vertices on the seam between the front and back are used by triangles on both sides, but require a correction
@@ -233,17 +254,17 @@ public class AliasModel
 
     private static Mesh CreateAnimatedMesh(
         QAliasHeader header, QTriVertex[][] poseVertices, ushort[] indices, Vector2[] uvs,
-        string animationName, int startFrame, int endFrame)
+        string animationName, int startPose, int endPose)
     {
-        ConvertVertices(header, poseVertices[startFrame], out var baseVertices, out var baseNormals);
+        ConvertVertices(header, poseVertices[startPose], out var baseVertices, out var baseNormals);
         
         var mesh = new Mesh { name = animationName };
         mesh.SetVertices(baseVertices);
         mesh.SetNormals(baseNormals);
 
-        if (endFrame - startFrame > 1)
+        if (endPose - startPose > 1)
         {
-            CreateBlendShapes(mesh, animationName, baseVertices, baseNormals, header, poseVertices, startFrame, endFrame);
+            CreateBlendShapes(mesh, animationName, baseVertices, baseNormals, header, poseVertices, startPose, endPose);
         }
 
         mesh.SetIndices(indices, MeshTopology.Triangles, 0, false);
@@ -256,7 +277,7 @@ public class AliasModel
 
     private static void CreateBlendShapes(
         Mesh mesh, string animName, Vector3[] baseVertices, Vector3[] baseNormals,
-        QAliasHeader header, QTriVertex[][] poseVertices, int startFrame, int endFrame)
+        QAliasHeader header, QTriVertex[][] poseVertices, int startPose, int endPose)
     {
         var deltaVertices = new Vector3[header.numVerts];
         var deltaNormals = new Vector3[header.numVerts];
@@ -264,13 +285,13 @@ public class AliasModel
         Vector3 scale = header.scale.ToVector3();
         Vector3 origin = header.scaleOrigin.ToVector3();
         
-        int numFrames = endFrame - startFrame;
+        int numPoses = endPose - startPose;
         
-        // Repeat the first frame at the end, so we can smoothly animate the entire cycle and loop the animation without any breaks.
-        for (int index = 1; index <= numFrames; ++index)
+        // Repeat the first pose at the end, so we can smoothly animate the entire cycle and loop the animation without any breaks.
+        for (int index = 1; index <= numPoses; ++index)
         {
-            int frameIdx = startFrame + index % numFrames;
-            var poseVerts = poseVertices[frameIdx];
+            int poseIdx = startPose + index % numPoses;
+            var poseVerts = poseVertices[poseIdx];
             
             for (int vertIdx = 0; vertIdx < header.numVerts; ++vertIdx)
             {
@@ -279,7 +300,7 @@ public class AliasModel
                 deltaNormals[vertIdx] = QLightNormals.Get(poseVerts[vertIdx].lightNormalIndex) - baseNormals[vertIdx];
             }
             
-            mesh.AddBlendShapeFrame(animName, (float)index / numFrames, deltaVertices, deltaNormals, null);
+            mesh.AddBlendShapeFrame(animName, (float)index / numPoses, deltaVertices, deltaNormals, null);
         }
     }
 }

Assets/Scripts/Modules/RenderModule.cs

@@ -48,7 +48,7 @@ public partial class RenderModule
         
         aliasModel.Animate(0, out Mesh mesh, out float blendWeight);
 
-        if (header.numFrames > 1)
+        if (header.numPoses > 1)
         {
             var mr = go.AddComponent<SkinnedMeshRenderer>();
             mr.material = new Material(Shader.Find("Universal Render Pipeline/Simple Lit"));