render.raymarch.render.raymarch

render.raymarch.render.raymarch(
    sdf,
    camera_pos=jnp.array([5.0, 5.0, 5.0]),
    look_at=jnp.array([0.0, 0.0, 0.0]),
    light_dirs=jnp.array([0.5, 1.0, 0.3]),
    light_colors=None,
    resolution=(200, 200),
    fov=0.6,
    max_steps=64,
    max_dist=20.0,
    shadow_steps=24,
    shadow_hardness=8.0,
    gamma=2.2,
    ambient=0.0,
    aa_samples=1,
    background_color=jnp.array([0.0, 0.0, 0.0]),
    refract_steps=0,
    fd_normals=False,
    normal_eps=0.0001,
    reflect_steps=0,
    env_map=None,
    trace_mode='sphere',
    bisect_steps=8,
)

Render an SDF via sphere tracing and return an RGB image array.

Uses jax.vmap over pixels and jax.lax.scan for the inner march loop. Supports multiple colored lights, transparency, refraction, and mirror reflections.

Parameters

Name	Type	Description	Default
sdf	Callable[[Array], Array]	Signed distance function, callable (point: Array[3]) → Array[].	required
camera_pos	Array	Camera position in world space.	jnp.array([5.0, 5.0, 5.0])
look_at	Array	Point the camera looks toward.	jnp.array([0.0, 0.0, 0.0])
light_dirs	Array	Light direction(s) toward the light source(s). Shape (3,) for a single light or (N, 3) for N lights.	jnp.array([0.5, 1.0, 0.3])
light_colors	Array | None	RGB color(s) of the light(s), shape (3,) or (N, 3). Defaults to white [1, 1, 1] for every light.	None
resolution	tuple[int, int]	Output image size as (height, width).	(200, 200)
fov	float	Half-width field-of-view parameter.	0.6
max_steps	int	Sphere tracing iterations per ray.	64
max_dist	float	Rays beyond this distance are treated as misses.	20.0
shadow_steps	int	Iterations for the soft shadow ray.	24
shadow_hardness	float	Shadow sharpness (higher = harder edges).	8.0
gamma	float	Gamma correction exponent (1.5 default, 2.2 = sRGB standard).	2.2
ambient	float	Constant ambient light added to all hit pixels (0 = fully black shadows, higher = lifted shadows).	0.0
aa_samples	int	Super-sampling factor for antialiasing. 1 = no AA; 2 = 2×2 SSAA (4× rays, box-filtered); 3 = 3×3, etc.	1
background_color	Array	RGB color returned for rays that miss all geometry. Ignored when env_map is provided. Default is black.	jnp.array([0.0, 0.0, 0.0])
refract_steps	int	Number of interior march steps for glass refraction. 0 disables refraction (legacy behaviour). Try 32–64 for glass.	0
fd_normals	bool	Use central finite differences for surface normals instead of jax.grad. Eliminates 2nd-order AD overhead when rendering inside jax.grad(loss_fn). Default False (AD normals).	False
normal_eps	float	Step size for finite-difference normal estimation.	0.0001
reflect_steps	int	Sphere-tracing iterations for mirror reflections (0 disables). Uses material reflectivity to blend. Try 32.	0
env_map	Array | None	Optional equirectangular HDR environment map, shape (H, W, 3). When set, miss rays and reflected rays that miss geometry sample this map instead of background_color. Load any .hdr or .exr file with imageio and pass through jnp.asarray, or generate one with :func:~jaxcad.render.raymarch.env.make_gradient_sky.	None

Returns

Name	Type	Description
	np.ndarray	Float32 numpy array of shape (H, W, 3) with values in [0, 1].