If you haven´t done it yet, you should try messing around with the DirecX SDK documentation. I just tried to check the texture format using: ((LPDIRECT3D9)pd3d)->CheckDeviceFormat(...) But the texture formats aren´t defined, so this needs some more defines....

I am still doing something wrong as it crashes, but I think that I am quite close:
Code:
#include <acknex.h>
#include <d3d9.h>

#define D3DFMT_A8R8G8B8 21
#define D3DFMT_X8R8G8B8 22

#define D3DFMT_R16F 111
#define D3DFMT_G16R16F 112
#define D3DFMT_A16B16G16R16F 113

#define D3DFMT_R32F 114
#define D3DFMT_G32R32F 115
#define D3DFMT_A32B32G32R32F 116

#define D3DRTYPE_SURFACE 1
#define D3DRTYPE_VOLUME 2
#define D3DRTYPE_TEXTURE 3
#define D3DRTYPE_VOLUMETEXTURE 4
#define D3DRTYPE_CubeTexture 5
#define D3DRTYPE_VERTEXBUFFER 6
#define D3DRTYPE_INDEXBUFFER 7

void main()
{
	level_load("");
	wait(1);
	((LPDIRECT3D9)pd3d)->CheckDeviceFormat(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, D3DFMT_X8R8G8B8, 0, D3DRTYPE_TEXTURE, D3DFMT_R32F);
}


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