added mi_max_count in Material

inc/hgl/graph/VKMaterial.h

@@ -35,6 +35,7 @@ class Material
     MaterialParameters *mp_array[DESCRIPTOR_SET_TYPE_COUNT];
 
     uint32_t mi_data_bytes;             ///<实例数据大小
+    uint32_t mi_max_count;              ///<实例一次渲染最大数量限制
     
     ActiveMemoryBlockManager *mi_data_manager;
 
@@ -76,6 +77,7 @@ public:
 public:
 
     const uint32_t GetMIDataBytes   ()const{return mi_data_bytes;}
+    const uint32_t GetMIMaxCount    ()const{return mi_max_count;}
 
     void ReleaseMI(int);    ///<释放材质实例
     void *GetMIData(int);   ///<取得指定ID号的材质实例数据访问指针