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nerfstudio/mattport/structures/rays.py
Ethan Weber fb440fedf3
Occupancy grid (#79)
* occupancy grid in progress

* visualizing occupancy grid. currently restructing field and renderer head outputs

* black and pylint. broke nerfw and semantic nerf but it's okay

* get_project_root
2022-05-17 19:09:25 -07:00

194 lines
6.7 KiB
Python

"""
Some ray datastructures.
"""
import random
from dataclasses import dataclass
from typing import Optional
import torch
from torchtyping import TensorType
from mattport.utils.misc import is_not_none
@dataclass
class PointSamples:
"""Samples in space."""
positions: TensorType[..., 3] = None
directions: TensorType[..., 3] = None
camera_indices: TensorType[..., 1] = None
@dataclass
class RayBundle:
"""_summary_
Returns:
_type_: _description_
"""
origins: TensorType["num_rays", 3]
directions: TensorType["num_rays", 3]
camera_indices: Optional[TensorType["num_rays"]] = None
nears: Optional[TensorType["num_rays"]] = None
fars: Optional[TensorType["num_rays"]] = None
valid_mask: Optional[TensorType["num_rays"]] = None
def to_camera_ray_bundle(self, image_height, image_width) -> "CameraRayBundle":
"""Returns a CameraRayBundle from this object."""
camera_ray_bundle = CameraRayBundle(
origins=self.origins.view(image_height, image_width, 3),
directions=self.directions.view(image_height, image_width, 3),
camera_indices=self.camera_indices.view(image_height, image_width)
if not isinstance(self.camera_indices, type(None))
else None,
)
return camera_ray_bundle
def move_to_device(self, device):
"""Move to a device."""
self.origins = self.origins.to(device)
self.directions = self.directions.to(device)
if not isinstance(self.camera_indices, type(None)):
self.camera_indices = self.camera_indices.to(device)
def __len__(self):
num_rays = self.origins.shape[0]
return num_rays
def sample(self, num_rays: int):
"""Returns a RayBundle as a subset of rays.
Args:
num_rays (int):
Returns:
RayBundle: _description_
"""
assert num_rays <= len(self)
indices = random.sample(range(len(self)), k=num_rays)
return RayBundle(
origins=self.origins[indices],
directions=self.directions[indices],
camera_indices=self.camera_indices[indices],
)
def get_masked_ray_bundle(self, valid_mask):
"""Return a masked instance of the ray bundle."""
return RayBundle(
origins=self.origins[valid_mask],
directions=self.directions[valid_mask],
camera_indices=self.camera_indices[valid_mask] if is_not_none(self.camera_indices) else None,
nears=self.nears[valid_mask] if is_not_none(self.nears) else None,
fars=self.fars[valid_mask] if is_not_none(self.fars) else None,
valid_mask=self.valid_mask[valid_mask] if is_not_none(self.valid_mask) else None,
)
@dataclass
class CameraRayBundle:
"""_summary_"""
origins: TensorType["image_height", "image_width", 3]
directions: TensorType["image_height", "image_width", 3]
camera_indices: Optional[TensorType["image_height", "image_width", 3]] = None
camera_index: int = None
def __post_init__(self):
if not isinstance(self.camera_index, type(None)):
self.set_camera_indices(self.camera_index)
def set_camera_indices(self, camera_index: int):
"""Sets the camera indices for a specific camera index."""
self.camera_index = camera_index
self.camera_indices = torch.ones_like(self.origins[..., 0]).long() * camera_index
def get_num_rays(self):
"""Return the number of rays in this bundle."""
image_height, image_width = self.origins.shape[:2]
num_rays = image_height * image_width
return num_rays
def to_ray_bundle(self) -> RayBundle:
"""_summary_
Returns:
RayBundle: _description_
"""
# TODO(ethan): handle camera_index
ray_bundle = RayBundle(origins=self.origins.view(-1, 3), directions=self.directions.view(-1, 3))
return ray_bundle
def get_row_major_sliced_ray_bundle(self, start_idx, end_idx):
"""Return a RayBundle"""
camera_indices = (
self.camera_indices.view(-1)[start_idx:end_idx] if not isinstance(self.camera_indices, type(None)) else None
)
return RayBundle(
origins=self.origins.view(-1, 3)[start_idx:end_idx],
directions=self.directions.view(-1, 3)[start_idx:end_idx],
camera_indices=camera_indices,
)
class RaySamples:
"""_summary_"""
def __init__(
self,
ts: TensorType["num_rays", "num_samples"],
ray_bundle: RayBundle,
) -> None:
self.ray_bundle = ray_bundle
self.ts = ts
self.positions = self.get_positions(ray_bundle)
self.directions = ray_bundle.directions.unsqueeze(1).repeat(1, self.positions.shape[1], 1)
self.deltas = self.get_deltas()
def to_point_samples(self):
"""Convert to PointSamples instance and return."""
# TODO: make this more interpretable
return PointSamples(positions=self.positions, directions=self.directions)
def get_camera_indices(self):
"""Returns camera indices."""
assert not isinstance(self.ray_bundle.camera_indices, type(None)), "Camera indices cannot be None here."
camera_indices = self.ray_bundle.camera_indices.unsqueeze(1).repeat(1, self.positions.shape[1])
return camera_indices
def get_positions(self, ray_bundle: RayBundle) -> TensorType["num_rays", "num_samples", 3]:
"""Returns positions."""
return ray_bundle.origins[:, None] + self.ts[:, :, None] * ray_bundle.directions[:, None]
def get_deltas(self) -> TensorType[..., "num_samples"]:
"""Returns deltas."""
dists = self.ts[..., 1:] - self.ts[..., :-1]
dist_inf = 1e10 * torch.ones_like(dists[..., -1:])
dists = torch.cat([dists, dist_inf], -1) # [N_rays, N_samples]
deltas = dists * torch.norm(self.ray_bundle.directions[..., None, :], dim=-1)
return deltas
def get_weights(self, densities: TensorType[..., "num_samples", 1]) -> TensorType[..., "num_samples"]:
"""Return weights based on predicted densities
Args:
densities (TensorType[..., "num_samples", 1]): Predicted densities for samples along ray
Returns:
TensorType[..., "num_samples"]: Weights for each sample
"""
delta_density = self.deltas * densities[..., 0]
alphas = 1 - torch.exp(-delta_density)
transmittance = torch.cumsum(delta_density[..., :-1], dim=-1)
transmittance = torch.cat(
[torch.zeros((*transmittance.shape[:1], 1)).to(densities.device), transmittance], axis=-1
)
transmittance = torch.exp(-transmittance) # [..., "num_samples"]
weights = alphas * transmittance # [..., "num_samples"]
return weights