Better way to deal with memory

Blitz3D Forums/Blitz3D Programming/Better way to deal with memory

Bobysait

(Posted 2009) [#1]

Hi.
I coded a dll to use my own function to peek/poke into memory ( using VC++ 2008 ) but I'm really not sure it's the best way to do this...
So If anyone has a better experience on this kind of things, he's welcome ^^

It works fine, and allows to :
Peek/Poke int, short, byte at memory address ( cf : MDT_Peek/Poke )
return Integer address of Type pointers ( cf : GetPointer(t.MyType) )
return pointer from string/Int/Float variables ( cf : GetInt/String/Float Pointer )

return String from memory address ( cf : GetPtrString$( pointer ) )

here is my stuff

obsolete !
Cf : code in post below

(updated)
+> The Compiled Dll <+

+> The Decls <+

Matty

(Posted 2009) [#2]

Forgive my ignorance, but why wouldn't you just use a bank?

Bobysait

(Posted 2009) [#3]

I made a simple test between my dll and the MemoryLib ( available on the code archive ), it seems my function is just a bit faster ( lucky me, but I don't know if the MemoryLib.dll that I use is not an old version... )

As I want to build a Script library, I would like to store pointers to array and types to manage "Class" support etc... and of course, I need it to be fast enough to run IA scripts, and else.

Graphics3D 800,600,0,2
SetBuffer BackBuffer()

D3DDev7=SystemProperty("Direct3DDevice7")

CountTest=100000000

t0=MilliSecs()
For i = 1 To CountTest
	Ptr1=PeekMemInt(D3DDev7)
Next
t1=MilliSecs()
For i = 1 To CountTest
	Ptr2=MDT_PeekInt(D3DDev7)
Next
t2=MilliSecs()

Print "MemLib : Res = "+ptr1+" time = "+(t1-t0)
Print "MdtLib : Res = "+ptr2+" time = "+(t2-t1)
WaitKey
End

I have a Problem dealing with float value... I hope I'll find a solution

Bobysait

(Posted 2009) [#4]

Forgive my ignorance, but why wouldn't you just use a bank?

1/ create a temorary bank (buffer)
2/ pass the Bank to the dll
3/ return the bank and compute results
... It is too long.

And, for the purpose, I need Type support for my script library. So bank won't help.

Bobysait

(Posted 2009) [#5]

Ok, now I can Get Floats
And , I don't know if it's a good way, but I get it 2 or 3 times faster than the MemoryLib.dll from the code archive... maybe I have some unsafe code, so I can't really expect it to be stable.

anyway, here is the c++ source code :


//GetMemAndPointer.dll

#define MDTEXP extern "C" _declspec(dllexport)
#define MDTCALL _stdcall

#define PEEK(addr)      (*(unsigned char *)(addr))
#define POKE(addr, b)   (*(unsigned char *)(addr) = (b))

MDTEXP int MDTCALL GetPointer( void* p ){return reinterpret_cast<int>(p);};
MDTEXP void MDTCALL GetInstance( int p ,void* res){res= (void*)p;};

MDTEXP float MDTCALL PeekMemF( int addr )
{	float val; unsigned char *ptr = (unsigned char *)&val;
	ptr[0]=PEEK(addr); ptr[1]=PEEK(addr+1); ptr[2]=PEEK(addr+2); ptr[3]=PEEK(addr+3);
	return val;
};

MDTEXP int MDTCALL PeekMemB( int addr ){	return PEEK(addr);};
MDTEXP int MDTCALL PeekMemS( int addr ){return (PEEK(addr)+(PEEK(addr+1)<<8));};
MDTEXP int MDTCALL PeekMemI( int addr ){return (PEEK(addr)+(PEEK(addr+1)<<8)+(PEEK(addr+2)<<16)+(PEEK(addr+3)<<24));};

MDTEXP void MDTCALL PokeMemB( unsigned char *addr , int b){	POKE(addr,b);};
MDTEXP void MDTCALL PokeMemS( unsigned char *addr , int s){POKE(addr,s & 0xff);POKE(addr+1,(s >> 8) & 0xff);};
MDTEXP void MDTCALL PokeMemI( unsigned char *addr , int i)
{POKE(addr,i & 0xff);POKE(addr+1,(i >> 8) & 0xff);POKE(addr+2,(i >> 16) & 0xff);POKE(addr+3,(i >> 24) & 0xff);};

MDTEXP const char* MDTCALL GetString( const char*addr ){ return (addr);};

MDTEXP const char* MDTCALL GetTypeString( int addr ,int FieldId)
{	// Get The Pointer of the field
	addr=PeekMemI(addr+FieldId*4);
	// Get The Pointer of the string and read the string at the address( PokeMemI(addr+8) = StringLen )
	return GetString((const char*)PeekMemI(addr+4));
};
MDTEXP int MDTCALL GetTypeInt( int addr ,int FieldId)
{	// Return the Integer value of the field
	return PeekMemI(addr+FieldId*4);
};
MDTEXP float MDTCALL GetTypeFloat( int addr ,int FieldId)
{	// Return the float value of the field
	addr=addr+FieldId*4;
	float val; unsigned char *ptr = (unsigned char *)&val;
	ptr[0]=PEEK(addr); ptr[1]=PEEK(addr+1); ptr[2]=PEEK(addr+2); ptr[3]=PEEK(addr+3);
	return val;
};

And Here are the compiled dll and the decls
+> The Compiled Dll <+
+> The Decls <+

And I 'm still looking for a way to get Int and Float pointers...
Here, I can only extract the fields of a type, using the GetPointer() function, but I can't grab pointers from blitz3d vars.

ZJP	(Posted 2009) [#6]

[French]
Des peeks et des pokes. Hummm!. Merci Boby ;)
[/French]

Peeks and pokes. Love that. thx

JP