caldera

Vulkan and rust experiments. The code is split into a core caldera crate and a few different examples. Everything is work in progress and unstable, but this repository is public in case the code is interesting for others.

Features

• Render graph implementation over Vulkan, featuring:
  • Automatic memory allocation of temporary buffers and images
  • Automatic placement of barriers and layout transitions
• Makes use of spark to manage Vulkan commands and extensions
• Live reload of shaders (not ray tracing pipeline shaders yet though)
• A procedural macro for descriptor set layouts
• Asynchronous loading of resources using rust async/.await

Examples

Examples can be run as follows:

make && cargo run --example <example_name> -- --help

The call to make is required to build shaders, which depends on glslangValidator. On windows, make for windows and the LunarG Vulkan SDK can provide these. Omit --help and add other command-line arguments as necessary for each sample.

In the table below, please follow the link in the name or image of each example for more information.

Screenshot	Description
	test_compute Initial test for synchronisation between compute and graphics. Implements a toy path tracer in a single compute shader, reads the result during rasterization of the UI.
	test_ray_tracing Test of the VK_KHR_acceleration_structure and VK_KHR_ray_tracing_pipeline extensions. Loads a PLY format mesh and draws a few instances using either rasterization or ray tracing.
	test_mesh_shader Test of the VK_NV_mesh_shader extension. Loads a PLY format mesh, makes some clusters, then draws the result using either the standard vertex pipeline or mesh shaders. Cluster-level backface culling is implemented efficiently in the task shader using subgroup operations from the GL_KHR_shader_subgroup_ballot GLSL extension.
	path_tracer A path tracer built on Vulkan ray tracing with support for spectral rendering and several different surfaces and light types. The implementation also makes use of the VK_KHR_buffer_device_address and VK_EXT_descriptor_indexing extensions for bindless buffers and textures respectively. The README for this example contains many more details. The scenes shown here are from these rendering resources made available by Benedikt Bitterli.
	coherent_hashing Implementation of Coherent Parallel Hashing, which is a useful GPU data structure for hash tables when the keys are coherent.

Potential Future Work

• Buffer views?
• Use futures for async loading
• Occlusion culling in mesh shader example
• Many path tracer features (tracked here)