Blitz3D buffer and C++ ?

I want to wrap the directx7 function with c++ :
SetTexture

but when i try to use with blitz it there is an error message : "Memory access violation"

Here is the C++ code:

BBDECL int BBCALL SetTexture(int Stage,IDirectDrawSurface7 *TextureBuffer)
{
	if (p_D3DDevice)
	{
		if (TextureBuffer)
		{
			int hr = p_D3DDevice->SetTexture(Stage,TextureBuffer);
			if (hr != 0)
				return 1;
		}
		else
		{
			return 2;
		}
	}
	return 0;
}

-----------------------------------------------------------------------------------

BBDECL is macro : extern "C" _desclspec(dllexport)
BBCALL is macro : _stdcall

p_D3DDevice is pointer of D3D Device initialised before with another functions.

The DECLS file

.lib "MyLib.dll"

SetTexture%(Stage,TextureBuffer) : "_SetTexture@8"

The blitz code

Graphics3D 800,600,0,2

; Get your system properties
DX7_GetDX7Handle()

; Simple Texture
Texture = CreateTexture(16,16)
LockBuffer TextureBuffer(Texture)
UnLockBuffer TextureBuffer(Texture)
; C++ Functions <<<<<<<<<<<<<<<<<<<<<<<<<
HR = SetTexture(0,Texturebuffer(Texture))
debuglog HR

Waitkey()
FreeTexture Texture
End

Any idea ? ! :)

Shouldn't that be:

HR = SetTexture(0,TextureBuffer(Texture))

?

I have made an error when i have post the code ! sorry :)
but don't solve my problem ? it's very strange ?

Any Idea ?

I want get buffer to :)

hey filax, did you turn on debug mode?

Are you sure you've got the correct handle to the DirectX7 Device?

i doubt its possible to access a texturebuffer like this, since texturebuffer() returns a handle to a blitz internal structure rather than a real dx texturebuffer...

you will have to work with banks to accomplish that...

OJay: I thought 'Texture' is the handle to the internal blitz structure and TextureBuffer(Texture) returns the actual pointer to the buffer. If not, what's the point of the TextureBuffer() function?

Texture buffer returns an internal Blitz pixel buffer. When you lock the texture it creates a pixel buffer and gives it to the user, and when it's unlocked the data is sent back to the texture. The abstraction is what allows you to use WritePixel/etc. on buffers without having to use WriteTexturePixel or WriteImagePixel and whatnot. This is all based on the assumption that Blitz3D works in a logical and abstracted manner. If I'm wrong, then god have mercy on Mark's soul.

i have tested it, for localized the IDirectDrawSurface7 pointeur, i'm used the memorylib with parameter on blitz3D SetTexture(Stage,PeekMemInt(TextureBuffer)+12), but i don't arrived to modify the Blend with TextureStage :(, anyone say how to do it ? maybe Mark :o)

did you LOCK the buffer before BEFORE your setTexture() and UNLOCK it AFTER it?

yes it' worked too with simple ReadPixel 0,0,Texturebuffer(Texture) :) his a same

To obtain valid DX7 surface pointers from B3D textures or images, pass their handle & frame

i.e
tex = LoadTexture("mytexture.jpg")

MyDxFunction(tex,0)

BBDECL void BBCALL MyDxFunction(unsigned int bbHandle, unsigned int bbFrame)
{
  IDirectDrawSurface7 *srcTex=NULL;
  srcTex = FromBBTexHandle(bbHhandle, bbFrame)
  ...
}

IDirectDrawSurface7* FromBBTexHandle(unsigned int handle,int frame)
{
	handle = (unsigned int) *((int*)(handle));
	handle = (unsigned int) *((int*)(handle+12));
	handle = (unsigned int) *((int*)(handle+(4 * frame)));
	if(handle==0) return 0;
	IDirectDrawSurface7 *srcTex=NULL;
	return (IDirectDrawSurface7*) *((int*)(handle+12));
}

IDirectDrawSurface7* FromBBImgHandle(unsigned int handle,int frame)
{
	handle = (unsigned int) *((int*)(handle+4));
	handle = (unsigned int) *((int*)(handle+(4 * frame)));
	if(handle==0) return 0;
	IDirectDrawSurface7 *srcTex=NULL;
	return (IDirectDrawSurface7*) *((int*)(handle+12));
}

Seyhajin, I'll get that code to you shortly! :)

oh really good Tom :o)

but it's possible to used a TextureStage for modify a native Blitz3D Blend ? i tried to wrap all TextureStage functions, but it's not worked :o(, any idea ?

thanks again ! :o)