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+////
+- Copyright (c) 2023, Google
+-
+- SPDX-License-Identifier: Apache-2.0
+-
+- Licensed under the Apache License, Version 2.0 the "License";
+- you may not use this file except in compliance with the License.
+- You may obtain a copy of the License at
+-
+-     http://www.apache.org/licenses/LICENSE-2.0
+-
+- Unless required by applicable law or agreed to in writing, software
+- distributed under the License is distributed on an "AS IS" BASIS,
+- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+- See the License for the specific language governing permissions and
+- limitations under the License.
+-
+////
+
+= Order-independent transparency with per-pixel ordered linked lists
+
+ifdef::site-gen-antora[]
+TIP: The source for this sample can be found in the https://github.com/KhronosGroup/Vulkan-Samples/tree/main/samples/api/oit_linked_lists[Khronos Vulkan samples github repository].
+endif::[]
+
+:pp: {plus}{plus}
+
+image::./images/sample.png[Sample]
+
+== Overview
+
+This sample implements an order-independent transparency (OIT) algorithm using per-pixel ordered linked lists.
+It renders 64 spheres with random color and opacity (from 0.2 to 1.0).
+It produces pixel-perfect results.
+
+== Algorithm
+
+The OIT algorithm consists of two passes: the _gather_ pass and the _combine_ pass.
+
+During the gather pass, the transparent geometry is rendered into per-pixel order linked lists.
+Each fragment color and depth is pushed into the linked list associated with its destination pixel.
+The linked lists head are stored into a storage image that is the size of the screen.
+The fragment data (color and depth) is stored into a storage buffer shared by all linked lists.
+
+The _combine_ pass is a screen-space operation.
+For each pixel, it sorts the fragments stored in the linked list of that pixel.
+It then alpha blends (in the shader code) them to produce the final transparent color and coverage.
+Finally, it alpha blends (via the fixed blend function) the transparent color into the backbuffer.
+
+The algorithm can produce pixel-perfect results, even with intersecting geometry.
+However, there is a catch.
+To keep performance high, the maximum number of sorted fragments per-pixel is limited to 16.
+For more than 16 fragments, the algorithm does its best effort to blend the extra fragments, but the results might be inaccurate.
+This is well enough for the sample, due to the way the objects are placed in the scene.
+In general, there is a trade-off between performance and correctness.
+To keep occupancy high, the maximum number of sorted fragments (`SORTED_FRAGMENT_MAX_COUNT` in `combine.frag`) should be kept low.
+To get correct results in every situation, that same number should be as high as possible.
+The artifacts resulting from a low number of sorted fragments per pixel can be observed by using the `Sorted fragments per pixel` option.
+
+== Options
+
+[cols="2,4,4"]
+|===
+| Option | Description | Comments
+
+| Sort fragments
+| Enable fragment sorting in the combine pass
+| This option, when disabled, is meant to demonstrate the visual issues that occur with non-sorted transparent geometry.
+
+| Camera auto-rotation
+| Enable the automatic rotation of the camera
+| 
+
+| Sorted fragments per pixel
+| Specify the maximum number of fragments sorted per pixel
+| This option, when set to a low number (e.g. 4), highlights the main weakness of the algorithm.
+
+| Background grayscale
+| Specify the grayscale value by which the background color is multiplied (0.0 to 1.0)
+| 
+|===
+
+== Tests
+
+This sample was tested on Windows.
+The validation layers were enabled and all reported issues were fixed.
+The sample was also tested on Linux during development.
+Both systems featured an AMD GPU.
+