registry/vulkan/appendices/VK_IMG_filter_cubic.txt

include::meta/VK_IMG_filter_cubic.txt[]

*Last Modified Date*::
    2016-02-23
*Contributors*::
  - Tobias Hector, Imagination Technologies

`VK_IMG_filter_cubic` adds an additional, high quality cubic filtering mode
to Vulkan, using a Catmull-Rom bicubic filter.
Performing this kind of filtering can be done in a shader by using 16
samples and a number of instructions, but this can be inefficient.
The cubic filter mode exposes an optimized high quality texture sampling
using fixed texture sampling functionality.

=== New Enum Constants

  * Extending elink:VkFilter:
  ** ename:VK_FILTER_CUBIC_IMG

  * Extending elink:VkFormatFeatureFlagBits
  ** ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_CUBIC_BIT_IMG

=== Example

Creating a sampler with the new filter for both magnification and
minification

[source,c++]
----------------------------------------
    VkSamplerCreateInfo createInfo =
    {
        VK_STRUCTURE_TYPE_SAMPLER_CREATE_INFO // sType
        // Other members set to application-desired values
    };

    createInfo.magFilter = VK_FILTER_CUBIC_IMG;
    createInfo.minFilter = VK_FILTER_CUBIC_IMG;

    VkSampler sampler;
    VkResult result = vkCreateSampler(
        device,
        &createInfo,
        &sampler);
----------------------------------------

=== Version History

 * Revision 1, 2016-02-23 (Tobias Hector)
   - Initial version