[[VK_EXT_depth_range_unrestricted]]
== VK_EXT_depth_range_unrestricted
*Name String*::
    VK_EXT_depth_range_unrestricted
*Extension Type*::
    Device extension
*Registered Extension Number*::
    14
*Status*::
    Draft
*Last Modified Data*::
    2017-06-22
*Revision*::
    1
*Dependencies*::
    - This extension is written against version 1.0 of the Vulkan API.
    - This extension requires Vulkan 1.0.
*Contributors*::
    - Daniel Koch, NVIDIA
    - Jeff Bolz, NVIDIA
*Contact*::
    - Piers Daniell (pdaniell 'at' nvidia.com)
*Overview*::
+
--
This extension removes the slink:VkViewport pname:minDepth and
pname:maxDepth restrictions that the values must be between `0.0` and `1.0`,
inclusive.
It also removes the same restriction on
slink:VkPipelineDepthStencilStateCreateInfo pname:minDepthBounds and
pname:maxDepthBounds.
Finally it removes the restriction on the pname:depth value in
slink:VkClearDepthStencilValue.
--

=== New Object Types
None.

=== New Enum Constants
None.

=== New Enums
None.

=== New Structures
None.

=== New Functions
None.

=== Issues
1) How do slink:VkViewport pname:minDepth and pname:maxDepth values outside
of the `0.0` to `1.0` range interact with
<<vertexpostproc-clipping,Primitive Clipping>>?

**RESOLVED**: The behavior described in <<vertexpostproc-clipping,Primitive
Clipping>> still applies.
If depth clamping is disabled the depth values are still clipped to [eq]#0
{leq} z~c~ {leq} w~c~# before the viewport transform.
If depth clamping is enabled the above equation is ignored and the depth
values are instead clamped to the slink:VkViewport pname:minDepth and
pname:maxDepth values, which in the case of this extension can be outside of
the `0.0` to `1.0` range.

2) What happens if a resulting depth fragment is outside of the `0.0` to
`1.0` range and the depth buffer is fixed-point rather than floating-point?

**RESOLVED**: The supported range of a fixed-point depth buffer is `0.0` to
`1.0` and depth fragments are clamped to this range.

=== Version History
  * Revision 1, 2017-06-22 (Piers Daniell)
    - Internal revisions