Sailing Renderer

Sailing Renderer is a C++20 / OpenGL 4.4 real-time graphics project. It began as University of Florida graduate coursework. The current tree adds scene/renderer separation, adaptive Gerstner water, PBR, PN surfaces, tessellated shadows, and GPU timestamp profiling.

Implemented

• Adaptive screen-space GPU tessellation on an 8×8 authored ocean mesh.
• Nine-wave Gerstner displacement and analytic normals in the tessellation-evaluation stage.
• Cook-Torrance / GGX water shading, dielectric Fresnel, cubemap reflection, ACES tone mapping.
• PN triangle hulls and PN quad sails.
• Tessellated directional and omnidirectional shadow passes.
• Normal, wireframe, and tessellation-LOD debug views.
• GPU timestamp queries and a --benchmark mode that writes JSON.
• Coarse world-XZ convex-hull SAT with CTest. Not 3D mesh collision and not rigid-body physics.

Architecture

Scene update (once)
     ↓
directional shadow → point shadow → boats / sails / rig → ocean

Application owns the window, camera, scene, and renderer. Render passes only read transforms. Visual boat height samples the same Gerstner function the water TES uses. Collision stays on a fixed-Y hull so SAT does not inherit wave motion.

Benchmarks

Committed benchmarks/latest.json on an RTX 4080 SUPER at 1920×1080, VSync off:

Mode	Ocean GPU mean	Total GPU mean	Est. tris
Fixed 16	0.094 ms	0.186 ms	25088
Adaptive 24 px/seg	0.095 ms	0.188 ms	19405

Adaptive mode drops estimated water triangles. Total GPU time stays around 0.19 ms. Triangle counts are CPU estimates (inner_tess² per patch), not hardware primitive counters.

Limits

• Collision is a coarse 2D convex-hull test in world XZ.
• Boat pitch/roll is a light visual sit on the Gerstner surface, not buoyancy.
• Interactive boat-to-boat latch has not been visually confirmed. Tests cover the SAT function.
• Environment reflection is one cubemap sample, not prefiltered IBL.
• The cloud skybox still has no recorded original license. See the repo THIRD_PARTY.md.

The older GitHub slug OpenGL-Sailing resolves to the same repository.