3DLABS Oxygen 402 - Manual (Page 34)

28 Dynamic Pictures Oxygen 3D Family
Z-Buffer Z-Buffer
The Oxygen 3D Family supports 16-bit or 24-bit Z-buffers. The default
depth is 16-bit. Dynamic Pictures recommends that you leave this
setting unchanged except when you are working with very large models
and see undesirable artifacts. Increased Z-buffer precision will allocate
up to 24-bits for Z-buffering, although the actual depth will depend on
available memory. Selecting
None will turn off the Z-buffer, and all 3D
acceleration. This should be avoided, unless you are working with 2D
graphics only and require the additional memory.
Texture Memory Texture Memory
A texel is an individual component of a texture map. Depending on
your texture mapping requirements, you can specify the texel bit depth
used in texture mapping. For best performance, keep textures stored as
32-bit texels by selecting the
Optimize for performance option.
If you are using large textures, select the Optimize for memory
utilization option. This will store textures at the currently selected
frame buffer bit depth. Despite a slight performance penalty, this
enables a larger dimensioned texture to be stored efficiently.
If you are not using texture mapping, select the Disable hardware
texture mapping option. This will free memory for other uses by
preventing memory allocation for texture mapping.
The Oxygen card can render textures whether or not memory is
available on the card, but texturing performance is much higher when
using on-card memory. If you are using textures and experience
performance degradation, try switching to settings that free up on-card
memory (e.g., lower resolution, smaller Z-buffer or fewer colors).
Dynamic Allocation Dynamic Allocation
After memory allocation for the front buffer, back buffer, and Z-buffer
is complete, the remaining memory is available for Alpha buffering,
stencil buffering or 2D bitmaps by checking the appropriate boxes. You
can also increase available memory by disabling double buffering.
To restore the original Memory Options settings, click the “Factory
Defaults” button. For additional assistance, click the “Help” button.