diff --git a/chip/ps4_gpu_regs.pas b/chip/ps4_gpu_regs.pas
index 7421af7c..bfc78ef3 100644
--- a/chip/ps4_gpu_regs.pas
+++ b/chip/ps4_gpu_regs.pas
@@ -235,7 +235,10 @@ type
    MAX_INDX:DWORD;
   end;
 
-  VGT_MULTI_PRIM_IB_RESET_INDX:TVGT_MULTI_PRIM_IB_RESET_INDX;
+  VGT_MULTI_PRIM:packed record
+   IB_RESET_EN  :TVGT_MULTI_PRIM_IB_RESET_EN;
+   IB_RESET_INDX:TVGT_MULTI_PRIM_IB_RESET_INDX;
+  end;
 
   VGT_OUTPUT_PATH_CNTL:TVGT_OUTPUT_PATH_CNTL;
 
diff --git a/chip/ps4_videodrv.pas b/chip/ps4_videodrv.pas
index 174ccfa3..93ac05bf 100644
--- a/chip/ps4_videodrv.pas
+++ b/chip/ps4_videodrv.pas
@@ -1280,7 +1280,8 @@ begin
 
   mmVGT_INDX_OFFSET      :DWORD(GPU_REGS.VGT_VTX_INDX.INDX_OFFSET):=value;
 
-  mmVGT_MULTI_PRIM_IB_RESET_INDX:DWORD(GPU_REGS.VGT_MULTI_PRIM_IB_RESET_INDX):=value;
+  mmVGT_MULTI_PRIM_IB_RESET_EN  :DWORD(GPU_REGS.VGT_MULTI_PRIM.IB_RESET_EN):=value;
+  mmVGT_MULTI_PRIM_IB_RESET_INDX:DWORD(GPU_REGS.VGT_MULTI_PRIM.IB_RESET_INDX):=value;
 
   mmVGT_OUTPUT_PATH_CNTL:DWORD(GPU_REGS.VGT_OUTPUT_PATH_CNTL):=value;
 
@@ -1766,7 +1767,9 @@ begin
 
   FRenderCmd.FFramebuffer.SetSize(GPU_REGS.GET_SCREEN_SIZE);
 
-  FRenderCmd.FPipeline.SetPrimType(GPU_REGS.GET_PRIM_TYPE);
+  FRenderCmd.FPipeline.SetPrimType (GPU_REGS.GET_PRIM_TYPE);
+  FRenderCmd.FPipeline.SetPrimReset(GPU_REGS.VGT_MULTI_PRIM.IB_RESET_EN.RESET_EN);
+
   FRenderCmd.FPipeline.SetBlendColors(@GPU_REGS.CB_BLEND_RGBA);
 
   //FRenderCmd.FPipeline.multisampling.sampleShadingEnable  :=VK_FALSE;
@@ -1890,7 +1893,7 @@ begin
 
    end;
 
-  //if not GPU_REGS.COMP_ENABLE then Exit(false);
+  if not GPU_REGS.COMP_ENABLE then Exit(false);
   if GPU_REGS.DB_ENABLE {false} then
   begin
    DB_INFO:=GPU_REGS.GET_DB_INFO;
@@ -2299,6 +2302,19 @@ begin
  //
 end;
 
+procedure test_reset_index(INDEX_TYPE:TVkIndexType;RESET_EN:Byte;IB_RESET_INDX:DWORD);
+begin
+ if (RESET_EN<>0) then
+ begin
+  Case INDEX_TYPE of
+   VK_INDEX_TYPE_UINT8_EXT:Assert(IB_RESET_INDX=$000000FF,'unsupport reset index:'+HexStr(IB_RESET_INDX,8));
+   VK_INDEX_TYPE_UINT16   :Assert(IB_RESET_INDX=$0000FFFF,'unsupport reset index:'+HexStr(IB_RESET_INDX,8));
+   VK_INDEX_TYPE_UINT32   :Assert(IB_RESET_INDX=$FFFFFFFF,'unsupport reset index:'+HexStr(IB_RESET_INDX,8));
+   else;
+  end;
+ end;
+end;
+
 procedure onDrawIndex2(pm4Hdr:PM4_TYPE_3_HEADER;Body:PPM4CMDDRAWINDEX2);
 var
  Addr:Pointer;
@@ -2312,13 +2328,26 @@ begin
 
   //drawInitiator:TVGT_DRAW_INITIATOR;
 
+ test_reset_index(GPU_REGS.GET_INDEX_TYPE,
+                  GPU_REGS.VGT_MULTI_PRIM.IB_RESET_EN.RESET_EN,
+                  GPU_REGS.VGT_MULTI_PRIM.IB_RESET_INDX);
+
  if UpdateGpuRegsInfo then
  begin
   Addr:=getIndexAddress(GPU_REGS.VGT_DMA.BASE_LO,GPU_REGS.VGT_DMA.BASE_HI);
   GFXRing.CmdBuffer.DrawIndex2(Addr,GPU_REGS.VGT_DMA.INDICES,GPU_REGS.GET_INDEX_TYPE);
  end;
 
- {$ifdef ww}Writeln('DrawIndex:',Body^.indexCount);{$endif}
+ {$ifdef ww}
+  Writeln('DrawIndex:',Body^.indexCount);
+  Writeln('VGT_VTX_INDX.CNT_EN         :',GPU_REGS.VGT_VTX_INDX.CNT_EN.VTX_CNT_EN);
+  Writeln('VGT_VTX_INDX.INDX_OFFSET    :',GPU_REGS.VGT_VTX_INDX.INDX_OFFSET);
+
+  Writeln('VGT_MULTI_PRIM.IB_RESET_EN  :',GPU_REGS.VGT_MULTI_PRIM.IB_RESET_EN.RESET_EN);
+  Writeln('VGT_MULTI_PRIM.IB_RESET_INDX:',HexStr(GPU_REGS.VGT_MULTI_PRIM.IB_RESET_INDX,8));
+ {$endif}
+
+
 
  //GFXMicroEngine.PushCmd(GFXRing.CmdBuffer);
 end;
@@ -2332,7 +2361,10 @@ begin
   GFXRing.CmdBuffer.DrawIndexAuto(GPU_REGS.VGT_DMA.INDICES);
  end;
 
- {$ifdef ww}Writeln('onDrawIndexAuto:',Body^.indexCount);{$endif}
+ {$ifdef ww}
+  Writeln('onDrawIndexAuto:',Body^.indexCount);
+  Writeln('VGT_VTX_INDX.CNT_EN:',GPU_REGS.VGT_VTX_INDX.CNT_EN.VTX_CNT_EN);
+ {$endif}
 
  //GFXMicroEngine.PushCmd(GFXRing.CmdBuffer);
 end;
@@ -2352,13 +2384,25 @@ begin
  GPU_REGS.VGT_DMA.SIZE    :=Body^.indexCount;
  GPU_REGS.VGT_DMA.INDICES :=Body^.indexCount;
 
+ test_reset_index(GPU_REGS.GET_INDEX_TYPE,
+                  GPU_REGS.VGT_MULTI_PRIM.IB_RESET_EN.RESET_EN,
+                  GPU_REGS.VGT_MULTI_PRIM.IB_RESET_INDX);
+
  if UpdateGpuRegsInfo then
  begin
   Addr:=getIndexAddress(GPU_REGS.VGT_DMA.BASE_LO,GPU_REGS.VGT_DMA.BASE_HI);
   GFXRing.CmdBuffer.DrawIndexOffset2(Addr,Body^.indexOffset,GPU_REGS.VGT_DMA.INDICES,GPU_REGS.GET_INDEX_TYPE);
  end;
 
- {$ifdef ww}Writeln('DrawIndexOffset2:',Body^.indexOffset,' ',Body^.indexCount);{$endif}
+ {$ifdef ww}
+  Writeln('DrawIndexOffset2:',Body^.indexOffset,' ',Body^.indexCount);
+
+  Writeln('VGT_VTX_INDX.CNT_EN         :',GPU_REGS.VGT_VTX_INDX.CNT_EN.VTX_CNT_EN);
+  Writeln('VGT_VTX_INDX.INDX_OFFSET    :',GPU_REGS.VGT_VTX_INDX.INDX_OFFSET);
+
+  Writeln('VGT_MULTI_PRIM.IB_RESET_EN  :',GPU_REGS.VGT_MULTI_PRIM.IB_RESET_EN.RESET_EN);
+  Writeln('VGT_MULTI_PRIM.IB_RESET_INDX:',HexStr(GPU_REGS.VGT_MULTI_PRIM.IB_RESET_INDX,8));
+ {$endif}
 
 end;
 
@@ -2380,6 +2424,7 @@ type
 procedure onNumInstances(pm4Hdr:PM4_TYPE_3_HEADER;Body:PVGT_DMA_NUM_INSTANCES);
 begin
  GPU_REGS.VGT_DMA.NUM_INSTANCES:=Body^;
+ Assert(GPU_REGS.VGT_DMA.NUM_INSTANCES<=1,'instancing TODO:'+IntToStr(GPU_REGS.VGT_DMA.NUM_INSTANCES));
  {$ifdef ww}Writeln('onNumInstances:',Body^);{$endif}
 end;
 
diff --git a/vulkan/vBuffer.pas b/vulkan/vBuffer.pas
index 8816485b..c0199820 100644
--- a/vulkan/vBuffer.pas
+++ b/vulkan/vBuffer.pas
@@ -23,7 +23,7 @@ type
  end;
 
 function VkBindSparseBufferMemory(queue:TVkQueue;buffer:TVkBuffer;bindCount:TVkUInt32;pBinds:PVkSparseMemoryBind):TVkResult;
-function GetRequirements(size:TVkDeviceSize;usage:TVkFlags;ext:Pointer=nil):TVkMemoryRequirements;
+function GetRequirements(sparce:boolean;size:TVkDeviceSize;usage:TVkFlags;ext:Pointer=nil):TVkMemoryRequirements;
 
 implementation
 
@@ -72,11 +72,14 @@ begin
  vkDestroyFence(Device.FHandle,fence,nil);
 end;
 
-function GetRequirements(size:TVkDeviceSize;usage:TVkFlags;ext:Pointer=nil):TVkMemoryRequirements;
+function GetRequirements(sparce:boolean;size:TVkDeviceSize;usage:TVkFlags;ext:Pointer=nil):TVkMemoryRequirements;
 var
  Buffer:TvBuffer;
 begin
- Buffer:=TvBuffer.Create(size,usage,ext);
+ Case sparce of
+  True :Buffer:=TvBuffer.CreateSparce(size,usage,ext);
+  False:Buffer:=TvBuffer.Create(size,usage,ext);
+ end;
  Result:=Buffer.GetRequirements;
  Buffer.Free;
 end;
diff --git a/vulkan/vHostBufferManager.pas b/vulkan/vHostBufferManager.pas
index 894f66a0..baaad9be 100644
--- a/vulkan/vHostBufferManager.pas
+++ b/vulkan/vHostBufferManager.pas
@@ -89,28 +89,65 @@ begin
  end;
 end;
 
-function _fix_buf_size(var Offset,Size:TVkDeviceSize;usage:TVkFlags):TVkDeviceSize;
-var
- mr:TVkMemoryRequirements;
- pAlign:TVkDeviceSize;
+function Max(a,b:QWORD):QWORD; inline;
 begin
- mr:=GetRequirements(Size,usage,@buf_ext);
-
- pAlign:=AlignDw(Offset,mr.alignment);
- Result:=(Offset-pAlign);
-
- Offset:=pAlign;
- Size  :=Size+Result;
-
- if (Size<mr.size) then Size:=mr.size;
+ if (a>b) then Result:=a else Result:=b;
 end;
 
-function _New_simple(host:TvPointer;Size:TVkDeviceSize;usage:TVkFlags):TvHostBuffer;
+function Min(a,b:QWORD):QWORD; inline;
+begin
+ if (a<b) then Result:=a else Result:=b;
+end;
+
+function _fix_buf_size(sparce:Boolean;var Addr:Pointer;var Size:TVkDeviceSize;usage:TVkFlags):TVkDeviceSize;
 var
+ mr:TVkMemoryRequirements;
+ pAlign:Pointer;
+begin
+ mr:=GetRequirements(sparce,Size,usage,@buf_ext);
+
+ pAlign:=AlignDw(Addr,mr.alignment);
+ Result:=(Addr-pAlign);
+
+ Addr:=pAlign;
+ Size:=Max(Size+Result,mr.size);
+end;
+
+function _is_sparce(Addr:Pointer;Size:TVkDeviceSize;usage:TVkFlags):Integer;
+var
+ host:TvPointer;
+ hsize:qword;
+begin
+ _fix_buf_size(False,Addr,Size,usage);
+
+ host:=Default(TvPointer);
+ if not TryGetHostPointerByAddr(addr,host,@hsize) then
+ begin
+  Exit(-1);
+ end;
+
+ if (hsize>=Size) then
+ begin
+  Result:=0;
+ end else
+ begin
+  Result:=1;
+ end;
+end;
+
+function _New_simple(Addr:Pointer;Size:TVkDeviceSize;usage:TVkFlags):TvHostBuffer;
+var
+ host:TvPointer;
+
  t:TvHostBuffer;
  delta:TVkDeviceSize;
 begin
- delta:=_fix_buf_size(host.FOffset,Size,usage);
+ Result:=nil;
+
+ delta:=_fix_buf_size(False,Addr,Size,usage);
+
+ host:=Default(TvPointer);
+ if not TryGetHostPointerByAddr(addr,host) then Exit;
 
  t:=TvHostBuffer.Create(Size,usage,@buf_ext);
 
@@ -121,11 +158,6 @@ begin
  Result:=t;
 end;
 
-function Min(a,b:QWORD):QWORD; inline;
-begin
- if (a<b) then Result:=a else Result:=b;
-end;
-
 function _New_sparce(queue:TVkQueue;Addr:Pointer;Size:TVkDeviceSize;usage:TVkFlags):TvHostBuffer;
 var
  host:TvPointer;
@@ -145,7 +177,7 @@ begin
  Result:=nil;
 
  //hack; alignment is the same in virtual memory
- delta:=_fix_buf_size(TVkDeviceSize(Addr),Size,usage);
+ delta:=_fix_buf_size(True,Addr,Size,usage);
 
  Binds:=Default(AVkSparseMemoryBind);
  host :=Default(TvPointer);
@@ -188,9 +220,6 @@ end;
 function FetchHostBuffer(cmd:TvCustomCmdBuffer;Addr:Pointer;Size:TVkDeviceSize;usage:TVkFlags):TvHostBuffer;
 var
  t:TvHostBuffer;
- host:TvPointer;
-
- _size:qword;
 
 label
  _exit;
@@ -217,20 +246,18 @@ begin
  if (t=nil) then
  begin
   //Writeln('NewBuf:',HexStr(Addr));
-  host:=Default(TvPointer);
-  if not TryGetHostPointerByAddr(addr,host,@_size) then
-  begin
-   Goto _exit;
-  end;
 
-  if (_size>=Size) then
-  begin
-   t:=_New_simple(host,Size,usage);
-  end else
-  begin //is Sparse buffers
-   Assert(vDevice.sparseBinding,'sparseBinding not support');
-   Assert(MemManager.SparceSupportHost,'sparse not support for host');
-   t:=_New_sparce(cmd.FQueue.FHandle,Addr,Size,usage);
+  t:=nil;
+  Case _is_sparce(Addr,Size,usage) of
+   0:begin
+      t:=_New_simple(Addr,Size,usage);
+     end;
+   1:begin  //is Sparse buffers
+      Assert(vDevice.sparseBinding,'sparseBinding not support');
+      Assert(MemManager.SparceSupportHost,'sparse not support for host');
+      t:=_New_sparce(cmd.FQueue.FHandle,Addr,Size,usage);
+     end;
+   else;
   end;
 
   t.FAddr:=addr;
diff --git a/vulkan/vRender.pas b/vulkan/vRender.pas
index 25c2badb..7b2e04ca 100644
--- a/vulkan/vRender.pas
+++ b/vulkan/vRender.pas
@@ -73,6 +73,7 @@ type
   emulate_primtype:Integer;
 
   Procedure SetPrimType(t:TVkPrimitiveTopology);
+  Procedure SetPrimReset(enable:TVkBool32);
   Procedure AddVPort(const V:TVkViewport;const S:TVkRect2D);
   Procedure AddBlend(const b:TVkPipelineColorBlendAttachmentState);
   Procedure Clear;
@@ -398,6 +399,11 @@ begin
  end;
 end;
 
+Procedure TvGraphicsPipeline.SetPrimReset(enable:TVkBool32);
+begin
+ inputAssembly.primitiveRestartEnable:=enable;
+end;
+
 Procedure TvGraphicsPipeline.AddVPort(const V:TVkViewport;const S:TVkRect2D);
 begin
  if (s.extent.width=0) or (s.extent.height=0) then Assert(false);