Working with Earlier Drivers

This section lists issues that can be encountered when working with Direct3D 9 on drivers written for versions of Direct3D earlier than Direct3D 9.

• When working with a T&L HAL device, the fog intensity is computed but the absolute value operation is not applied to this value. Rather, the value is left negative if that is what is computed. The best way to avoid this situation is to set up transforms appropriately. A less-preferred method is to make the fog-start and fog-end values negative to match.

To check for a Direct3D 9 driver, look for a nonzero value for D3DDEVCAPS2_STREAMOFFSET in the DevCaps2 member of D3DCAPS9.