A state block is essentially a device state snapshot, that can be applied to the device in a single call.

The device state block is either taken directly from the device or explicitly recorded one command at a time.

To record, TDx_3DDevice::BeginStateBlock() is called, followed by any or all of the following calls:
TDx_3DDevice::LightEnable()
TDx_3DDevice::SetClipPlane()
TDx_3DDevice::SetLight()
TDx_3DDevice::SetMaterial()
TDx_3DDevice::SetRenderState()
TDx_3DDevice::SetTexture()
TDx_3DDevice::SetTextureStageState()
TDx_3DDevice::SetTransform()
TDx_3DDevice::SetViewport()
Once the state block is completed, TDx_3DDevice::EndStateBlock() is called and a pointer to the recorded state block is returned.

If the same state is defined multiple times, only the last value will be used.