Reorder Memory - Copy Memory

[kevin]

  Reorder Memory

 This example is reordering bytes...    

PlayBASIC Code: [Select]

   Message$    ="This is a string"

   Size        =Len(Message$)
               
   SrcBank      = newBank(size)
   DestBank     = newBank(size)

   PokeBankString SrcBank,0,Message$,Len(Message$)


   for Testlp=0 to 4
      OrderBank   = newBank(size*4)

      select TestLP
      
            // ------------------------------------------
            case 1 //  backwards
            // ------------------------------------------

               for lp =0 to Size-1
                     pokebankint OrderBANK,lp*4,(Size-1)-lp      
               next
      
   
            // ------------------------------------------
            case 2 //  Wrap Bytes 
            // ------------------------------------------

               for lp =0 to Size-2 
                     pokebankint OrderBANK, lp*4      ,lp+1      
               next
               pokebankint OrderBANK, lp*4      ,Size-1      
   
         

            // ------------------------------------------
            case 3 //  
            // ------------------------------------------

               Top      =Size-1
               Bottom    = 0
               for lp =0 to Size/2
                     pokebankint OrderBANK, lp*4      ,lp
               next

               for lp =lp to Size-1
                     pokebankint OrderBANK, lp*4      ,Top
                     Top--
               next
         

            // ------------------------------------------
            case 4 //  
            // ------------------------------------------

               Dim Indexes(Size)
               
               for lp =0 to Size
                     Indexes(lp)=lp
               next

               for lp =0 to Size
                     Index=rnd(Size)
                     A=Indexes(lp)
                     B=Indexes(Index)
                     
                     Indexes(lp)      =B
                     Indexes(Index)   =A
                     
               next

               for lp =0 to Size-1
                     pokebankint OrderBANK, lp*4      ,INdexes(lp)
               next

         
            // ------------------------------------------
            default
            // ------------------------------------------
      
               ; create the ordering tabel..  
      
               for lp =0 to Size-1
                     pokebankint OrderBANK,lp*4,lp      
               next
      
      endselect


      ; suffle the memory from the source buffer to the target
      ReorderMemory GetBankPtr(SrcBank),GetBankPtr(DestBank),GetBankPtr(OrderBank), Size
   
      Message2$=PeekBankString(DestBank,0,Size)
   
      print " Input Message:"+Message$
      print "Output Message:"+Message2$
      print ""

      deletebank OrderBank
      Sync

   next

   waitkey


Function ReorderMemory(SrcPtr,DestPtr,ReorderTablePTR, Size)
   
      For lp=0 to Size-1
            Position=PeekInt(ReorderTablePTR)
            POkeByte DestPTR+Position, PeekByte(SrcPTR+lp)
            ReorderTablePTR+=4
      next
      
EndFunction

Remap Memory and Reorder Memory

    This example includes a second version of the function will copymemory but while reading and writign to the user defined offsets.   This allows the programming to convert the byte pattern during the copy.

PlayBASIC Code: [Select]

      Test_ReMapMemory()
      Test_ReorderMemory()

      waitkey
      


Function Test_ReorderMemory()
   
   print ""
   
   Message$    ="This is a string"

   Size        =Len(Message$)
               
   SrcBank      = newBank(size)
   DestBank     = newBank(size)

   PokeBankString SrcBank,0,Message$,Len(Message$)

   for Testlp=0 to 4
      OrderBank   = newBank(size*4)

      select TestLP
      
            // ------------------------------------------
            case 1 //  backwards
            // ------------------------------------------

               for lp =0 to Size-1
                     pokebankint OrderBANK,lp*4,(Size-1)-lp      
               next
      
            // ------------------------------------------
            case 2 //  Wrap Bytes 
            // ------------------------------------------

               for lp =0 to Size-2 
                     pokebankint OrderBANK, lp*4      ,lp+1      
               next
               pokebankint OrderBANK, lp*4      ,Size-1      
   
         
            // ------------------------------------------
            case 3 //  
            // ------------------------------------------

               Top      =Size-1
               Bottom    = 0
               for lp =0 to Size/2
                     pokebankint OrderBANK, lp*4      ,lp
               next

               for lp =lp to Size-1
                     pokebankint OrderBANK, lp*4      ,Top
                     Top--
               next
         

            // ------------------------------------------
            case 4 //  
            // ------------------------------------------

               Dim Indexes(Size)
               
               for lp =0 to Size
                     Indexes(lp)=lp
               next

               for lp =0 to Size
                     Index=rnd(Size)
                     A=Indexes(lp)
                     B=Indexes(Index)
                     
                     Indexes(lp)      =B
                     Indexes(Index)   =A
                     
               next

               for lp =0 to Size-1
                     pokebankint OrderBANK, lp*4      ,INdexes(lp)
               next

         
            // ------------------------------------------
            default
            // ------------------------------------------
      
               ; create the ordering tabel..  
      
               for lp =0 to Size-1
                     pokebankint OrderBANK,lp*4,lp      
               next
      
      endselect


      ; suffle the memory from the source buffer to the target
      ReorderMemory GetBankPtr(SrcBank),GetBankPtr(DestBank),GetBankPtr(OrderBank), Size
   
      Message2$=PeekBankString(DestBank,0,Size)
   
      print " Input Message:"+Message$
      print "Output Message:"+Message2$
      print ""

      deletebank OrderBank
      Sync

   next


EndFunction


   
      
Function ReorderMemory(SrcPtr,DestPtr,ReorderTablePTR, Size)
      For lp=0 to Size-1
            Position=PeekInt(ReorderTablePTR)
            POkeByte DestPTR+Position, PeekByte(SrcPTR+lp)
            ReorderTablePTR+=4
      next
EndFunction



Function Test_RemapMemory()
    
    
    print ""
    
   Message$     = "Lets test remap memory function"

   
   for Testlp=0 to 2

      Size         = Len(Message$)

      SrcBank      = newBank(size*10)
      DestBank     = newBank(size*10)

      OrderBank   = newBank(size*10)

      PokeBankString SrcBank,0,Message$,Size



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