| // Copyright (c) 2019-2020 NVIDIA Corporation |
| // |
| // SPDX-License-Identifier: CC-BY-4.0 |
| |
| include::{generated}/meta/{refprefix}VK_NV_coverage_reduction_mode.txt[] |
| |
| === Other Extension Metadata |
| |
| *Last Modified Date*:: |
| 2019-01-29 |
| *Contributors*:: |
| - Kedarnath Thangudu, NVIDIA |
| - Jeff Bolz, NVIDIA |
| |
| === Description |
| |
| When using a framebuffer with mixed samples, a per-fragment coverage |
| reduction operation is performed which generates color sample coverage from |
| the pixel coverage. |
| This extension defines the following modes to control how this reduction is |
| performed. |
| |
| * Merge: When there are more samples in the pixel coverage than color |
| samples, there is an implementation-dependent association of each pixel |
| coverage sample to a color sample. |
| In the merge mode, the color sample coverage is computed such that only |
| if any associated sample in the pixel coverage is covered, the color |
| sample is covered. |
| This is the default mode. |
| |
| * Truncate: When there are more raster samples (N) than color samples(M), |
| there is one to one association of the first M raster samples to the M |
| color samples; other raster samples are ignored. |
| |
| When the number of raster samples is equal to the color samples, there is a |
| one to one mapping between them in either of the above modes. |
| |
| The new command |
| flink:vkGetPhysicalDeviceSupportedFramebufferMixedSamplesCombinationsNV can |
| be used to query the various raster, color, depth/stencil sample count and |
| reduction mode combinations that are supported by the implementation. |
| This extension would allow an implementation to support the behavior of both |
| `VK_NV_framebuffer_mixed_samples` and `VK_AMD_mixed_attachment_samples` |
| extensions simultaneously. |
| |
| include::{generated}/interfaces/VK_NV_coverage_reduction_mode.txt[] |
| |
| === Version History |
| |
| * Revision 1, 2019-01-29 (Kedarnath Thangudu) |
| - Internal revisions |
