engine: handle swapping sequence files in LoadCacheFile for games with external StudioModelRenderer

engine/common/mod_local.h

@@ -191,6 +191,7 @@ void Mod_StudioGetAttachment( const edict_t *e, int iAttachment, float *org, flo
 void Mod_GetBonePosition( const edict_t *e, int iBone, float *org, float *ang );
 hull_t *Mod_HullForStudio( model_t *m, float frame, int seq, vec3_t ang, vec3_t org, vec3_t size, byte *pcnt, byte *pbl, int *hitboxes, edict_t *ed );
 void *R_StudioGetAnim( studiohdr_t *m_pStudioHeader, model_t *m_pSubModel, mstudioseqdesc_t *pseqdesc );
+void Mod_SwapStudioSeqGroupAnims( studiohdr_t *phdr, mstudioseqdesc_t *pseq, byte *buf );
 int Mod_HitgroupForStudioHull( int index );
 void Mod_ClearStudioCache( void );
 

engine/common/mod_studio.c

@@ -550,7 +550,7 @@ static void Mod_StudioCalcRotations( int boneused[], int numbones, const byte *p
 }
 
 
-static void Mod_SwapStudioSeqGroupAnims( studiohdr_t *phdr, mstudioseqdesc_t *pseq, byte *buf )
+void Mod_SwapStudioSeqGroupAnims( studiohdr_t *phdr, mstudioseqdesc_t *pseq, byte *buf )
 {
 	mstudioanim_t *panim = (mstudioanim_t *)( buf + pseq->animindex );
 	int numanims = pseq->numblends * phdr->numbones;

engine/common/model.c

@@ -608,6 +608,31 @@ void GAME_EXPORT Mod_LoadCacheFile( const char *filename, cache_user_t *cu )
 	cu->data = Mem_Malloc( com_studiocache, size );
 	memcpy( cu->data, buf, size );
 	Mem_Free( buf );
+
+	// this handles when studio model renderer tries to load sequence files on it's own
+	// which is what they always do in HLSDK
+#if XASH_BIG_ENDIAN
+	if( size >= sizeof( int ) && LittleLong( IDSEQGRPHEADER ) == *(uint *)cu->data )
+	{
+		studiohdr_t *phdr = (studiohdr_t *)(intptr_t)REF_GET_PARM( PARM_GET_STUDIO_HDR, 0 );
+		if( !phdr )
+			return;
+
+		mstudioseqdesc_t *pseq = (mstudioseqdesc_t *)((byte *)phdr + phdr->seqindex );
+
+		for( int i = 0; i < phdr->numseq; i++ )
+		{
+			if( pseq[i].seqgroup == 0 )
+				continue;
+
+			mstudioseqgroup_t *pgrp = (mstudioseqgroup_t *)((byte *)phdr + phdr->seqgroupindex ) + pseq[i].seqgroup;
+
+			// assuming filename passes seqgroup's name
+			if( !Q_stricmp( pgrp->name, filename ))
+				Mod_SwapStudioSeqGroupAnims( phdr, &pseq[i], (byte *)cu->data );
+		}
+	}
+#endif
 }
 
 /*

engine/ref_api.h

@@ -342,6 +342,7 @@ typedef enum
 	PARM_GET_LIGHTSTYLES_PTR = -20,
 	PARM_GET_DLIGHTS_PTR = -21,
 	PARM_GET_ELIGHTS_PTR = -22,
+	PARM_GET_STUDIO_HDR = -23, // current m_pStudioHeader in renderer
 
 	// implemented by ref_dll