GeoClip

A minimal Vulkan 1.3 renderer written in C++23, using modern Vulkan extensions exclusively — no render passes, no pipeline state objects, no descriptor pools.

Currently renders the KhronosGroup DamagedHelmet glTF model with Blinn-Phong lighting, a D32 depth buffer, and Y-axis rotation.

Prerequisites

Requirement	Notes
Vulkan 1.3 GPU	Must support VK_EXT_shader_object and VK_EXT_descriptor_buffer
CMake ≥ 3.25	Required for preset support
Ninja	Used by all CMake presets
slangc	Slang compiler — compiles .slang shaders to SPIR-V 1.4 at build time
GCC 13+ or Clang 17+	C++23 required

Build

git submodule update --init --recursive

# Debug
cmake --preset debug
cmake --build build/debug

# Release
cmake --preset release
cmake --build build/release

Run

# Run from the project root — the glTF asset path is relative
./build/debug/GeoClip

Rendering architecture

Extension	Effect
VK_KHR_dynamic_rendering	No render passes or framebuffers — vkCmdBeginRendering directly
VK_EXT_shader_object	No PSOs — shaders bound per-draw; all rasterisation state set dynamically each frame
VK_EXT_descriptor_buffer	Descriptors live in a GPU buffer instead of descriptor pools
VK_KHR_synchronization2	vkCmdPipelineBarrier2 / vkQueueSubmit2
volk	Vulkan meta-loader — function pointers loaded at runtime; no link against Vulkan::Vulkan

Dependencies

All dependencies are git submodules under third_party/.

Library	Role
SDL3	Window, input, Vulkan surface
volk	Vulkan meta-loader
VulkanMemoryAllocator	GPU memory allocation
glm	Math
fastgltf	glTF 2.0 loading
ImGui	Debug UI (integrated, not yet used)
glTF-Sample-Assets	Test mesh (DamagedHelmet)