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+////
+- Copyright (c) 2023, Mobica Limited
+-
+- 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.
+-
+////
+= Geometry shader to mesh shader
+
+ifdef::site-gen-antora[]
+TIP: The source for this sample can be found in the https://github.com/KhronosGroup/Vulkan-Samples/tree/main/samples/extensions/gshader_to_mshader[Khronos Vulkan samples github repository].
+endif::[]
+
+
+image::./images/visualization_of_normals.png[Sample]
+
+== Overview
+
+This sample demonstrates how a mesh shader can be used to achieve the same results as with geometry shader.
+It contains geometry and mesh shader pipelines visualizing normals in the teapot model.
+
+== Meshlets
+
+To access model vertices from within mesh shader it needs to be stored within an **S**hader **S**torage **B**uffer **O**bject (SSBO).
+Indices need to be divided into meshlets and also stored within an SSBO so each work item can work on a single meshlet.
+Meshlets are created by spliting source geometry.
+Exemplary meshlet structure used in this sample:
+
+[,C++]
+----
+struct Meshlet
+{
+	uint32_t vertices[64];
+	uint32_t indices[126];
+	uint32_t vertex_count;
+	uint32_t index_count;
+};
+----
+
+By linearly scanning the indices of the model, Meshlet-structures are created with up to 126 indices or 64 unique vertex indices, whatever is reached first.
+See prepare_meshlets() for an exemplary implementation.
+
+This sample expands function `load_model()` by adding a bool storage_buffer parameter, set to false by default.
+In that function model data is read from the file teapot.gltf.
+By setting storage_buffer to true, vertex position and normals are stored in an SSBO using the `AlignedVertex` structure (because of std430 memory layout).
+After that, indices are divided into meshlets using the `Meshlet` structure and also stored in SSBOs.
+
+== Enabling the Extension
+
+The device extension is provided by `VK_EXT_MESH_SHADER_EXTENSION_NAME`.
+It requires `VK_KHR_SPIRV_1_4_EXTENSION_NAME`, which in turn require VulkanAPI 1.1 and `VK_KHR_SHADER_FLOAT_CONTROLS_EXTENSION_NAME`.
+SPIRV needs to be set to 1.4.
+
+[,C++]
+----
+set_api_version(VK_API_VERSION_1_1);
+add_device_extension(VK_EXT_MESH_SHADER_EXTENSION_NAME);
+add_device_extension(VK_KHR_SPIRV_1_4_EXTENSION_NAME);
+add_device_extension(VK_KHR_SHADER_FLOAT_CONTROLS_EXTENSION_NAME);
+vkb::GLSLCompiler::set_target_environment(glslang::EShTargetSpv, glslang::EShTargetSpv_1_4);
+----
+
+The `VkPhysicalDeviceMeshShaderFeaturesEXT` structure needs to be included in the pNext chain of the `VkPhysicalDeviceFeatures2` structure passed to vkGetPhysicalDeviceFeatures2
+
+[,C++]
+----
+auto &requested_vertex_input_features      = gpu.request_extension_features<VkPhysicalDeviceMeshShaderFeaturesEXT>(VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_MESH_SHADER_FEATURES_EXT);
+requested_vertex_input_features.meshShader = VK_TRUE;
+----
+
+== Pros and cons
+
+Usage of geometry shader is usually not advised for real-time rendering purposes as it leads to high memory bandwith and reduced performance.
+On the other hand it is part of traditional pipeline and doesn't require additional pre-procesing of source geometry opposite to mesh shader.
+
+Mesh shader offers better performance and is more flexible in it potential usage but in case of working with a source geometry pre-processing is needed (meshlets).