Files
nerfstudio/nerfstudio/model_components/shaders.py
T
2023-02-03 11:21:54 -08:00

78 lines
2.4 KiB
Python

# Copyright 2022 The Nerfstudio Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Shaders for rendering."""
from typing import Optional
from torch import nn
from torchtyping import TensorType
class LambertianShader(nn.Module):
"""Calculate Lambertian shading."""
@classmethod
def forward(
cls,
rgb: TensorType["bs":..., 3],
normals: TensorType["bs":..., 3],
light_direction: TensorType["bs":..., 3],
shading_weight: float = 1.0,
detach_normals=True,
):
"""Calculate Lambertian shading.
Args:
rgb: Accumulated rgb along a ray.
normals: Accumulated normals along a ray.
light_direction: Direction of light source.
shading_weight: Lambertian shading (1.0) vs. ambient lighting (0.0) ratio
detach_normals: Detach normals from the computation graph when computing shading.
Returns:
Textureless Lambertian shading, Lambertian shading
"""
if detach_normals:
normals = normals.detach()
lambertian = (1 - shading_weight) + shading_weight * (normals @ light_direction).clamp(min=0)
shaded = lambertian.unsqueeze(-1).repeat(1, 3)
shaded_albedo = rgb * lambertian.unsqueeze(-1)
return shaded, shaded_albedo
class NormalsShader(nn.Module):
"""Calculate shading for normals."""
@classmethod
def forward(
cls,
normals: TensorType["bs":..., 3],
weights: Optional[TensorType["bs":..., 1]] = None,
):
"""Applies a rainbow colormap to the normals.
Args:
normals: Normalized 3D vectors.
weights: Optional weights to scale to the normal colors. (Can be used for masking)
Returns:
Colored normals
"""
normals = (normals + 1) / 2
if weights is not None:
normals = normals * weights
return normals