sdfii 0.1.0

Python frontend for the sdfii Zig SDF engine

sdfii

A game engine built on signed distance functions.

Geometry is defined by composable SDF primitives. Physics is differentiable end-to-end. Audio uses TidalCycles-style pattern algebra. The runtime layer is reactive, based on the Syndicate model.

Concise, expressive, and intensely programmable. Bon appetit!

Quick start (Python)

pip install sdfii

import sdfii

# Build a scene from SDF primitives.
scene = sdfii.smooth_union(
    sdfii.sphere(radius=0.5),
    sdfii.box(0.8, 0.8, 0.8).translate(0.5, 0.5, 0),
    k=0.3,
)

# Compile and render in the terminal.
with sdfii.Engine() as engine:
    engine.compile(scene)
    engine.build_scene()
    sdfii.terminal_render(engine, width=120, height=40, dt=1 / 60)

Quick start (Zig)

const sdf = @import("sdf");

var builder = sdf.ExprBuilder.init(allocator);
const sphere = try builder.primitive(.sphere, &.{ .radius = 0.5 });
const box = try builder.primitive(.box, &.{ .size = .{ 1, 1, 1 } });
const scene = try builder.binary(.union_, sphere, box);
const program = try sdf.compile(allocator, scene);
const d = sdf.eval(program, .{ 0, 0.5, 0 });

Modules

Module	What it does
sdf	Expression trees, compilation to flat tapes, interval analysis
scene	Incremental scene compilation with dirty detection
query	Distance, gradient, contact, raycast, sweep queries
physics	Differentiable compliant contact simulation
dataspace	Reactive assertion store (Syndicate model)
ecs	Sparse-set entity storage with reactive change tracking
world	Batched mutation protocol over the ECS kernel
engine	Frame orchestrator, C ABI surface
audio	TidalCycles-style pattern algebra for audio synthesis
gamelib	Animation, navigation, inverse design, WoS PDE solving
backend	Compute backend selection and routing
raymarch	CPU sphere tracer for terminal and headless rendering
gpu	CUDA and Metal ray marching backends
testing	Property-based testing with byte-stream shrinking
ffi	Shared extern struct definitions for the C boundary
assets	Authored SDF geometry catalog with change fingerprinting

Building

Requires Zig 0.14+.

cd native/sdfii
zig build
zig build test

GPU backends build separately: gpu/cuda/ (requires nvcc) and gpu/metal/ (macOS, requires Metal framework).

License

MIT. See LICENSE.