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Magic123/taichi_modules/volume_train.py
Guocheng Qian 13e18567fa first commit
2023-08-02 19:51:43 -07:00

240 lines
9.2 KiB
Python

import taichi as ti
import torch
from torch.cuda.amp import custom_bwd, custom_fwd
from .utils import (data_type, ti2torch, ti2torch_grad, torch2ti,
torch2ti_grad, torch_type)
@ti.kernel
def composite_train_fw_array(
sigmas: ti.types.ndarray(),
rgbs: ti.types.ndarray(),
deltas: ti.types.ndarray(),
ts: ti.types.ndarray(),
rays_a: ti.types.ndarray(),
T_threshold: float,
total_samples: ti.types.ndarray(),
opacity: ti.types.ndarray(),
depth: ti.types.ndarray(),
rgb: ti.types.ndarray(),
ws: ti.types.ndarray(),
):
for n in opacity:
ray_idx = rays_a[n, 0]
start_idx = rays_a[n, 1]
N_samples = rays_a[n, 2]
T = 1.0
samples = 0
while samples < N_samples:
s = start_idx + samples
a = 1.0 - ti.exp(-sigmas[s] * deltas[s])
w = a * T
rgb[ray_idx, 0] += w * rgbs[s, 0]
rgb[ray_idx, 1] += w * rgbs[s, 1]
rgb[ray_idx, 2] += w * rgbs[s, 2]
depth[ray_idx] += w * ts[s]
opacity[ray_idx] += w
ws[s] = w
T *= 1.0 - a
# if T<T_threshold:
# break
samples += 1
total_samples[ray_idx] = samples
@ti.kernel
def composite_train_fw(sigmas: ti.template(), rgbs: ti.template(),
deltas: ti.template(), ts: ti.template(),
rays_a: ti.template(), T_threshold: float,
T: ti.template(), total_samples: ti.template(),
opacity: ti.template(), depth: ti.template(),
rgb: ti.template(), ws: ti.template()):
ti.loop_config(block_dim=256)
for n in opacity:
ray_idx = ti.i32(rays_a[n, 0])
start_idx = ti.i32(rays_a[n, 1])
N_samples = ti.i32(rays_a[n, 2])
rgb[ray_idx, 0] = 0.0
rgb[ray_idx, 1] = 0.0
rgb[ray_idx, 2] = 0.0
depth[ray_idx] = 0.0
opacity[ray_idx] = 0.0
total_samples[ray_idx] = 0
T[start_idx] = 1.0
# T_ = 1.0
# samples = 0
# while samples<N_samples:
for sample_ in range(N_samples):
# T_ = T[ray_idx, samples]
s = start_idx + sample_
T_ = T[s]
if T_ > T_threshold:
# s = start_idx + sample_
a = 1.0 - ti.exp(-sigmas[s] * deltas[s])
w = a * T_
rgb[ray_idx, 0] += w * rgbs[s, 0]
rgb[ray_idx, 1] += w * rgbs[s, 1]
rgb[ray_idx, 2] += w * rgbs[s, 2]
depth[ray_idx] += w * ts[s]
opacity[ray_idx] += w
ws[s] = w
# T_ *= (1.0-a)
T[s + 1] = T_ * (1.0 - a)
# if T[s+1]>=T_threshold:
# samples += 1
total_samples[ray_idx] += 1
else:
T[s + 1] = 0.0
# total_samples[ray_idx] = N_samples
@ti.kernel
def check_value(
fields: ti.template(),
array: ti.types.ndarray(),
checker: ti.types.ndarray(),
):
for I in ti.grouped(array):
if fields[I] == array[I]:
checker[I] = 1
class VolumeRendererTaichi(torch.nn.Module):
def __init__(self, batch_size=8192, data_type=data_type):
super(VolumeRendererTaichi, self).__init__()
# samples level
self.sigmas_fields = ti.field(dtype=data_type,
shape=(batch_size * 1024, ),
needs_grad=True)
self.rgbs_fields = ti.field(dtype=data_type,
shape=(batch_size * 1024, 3),
needs_grad=True)
self.deltas_fields = ti.field(dtype=data_type,
shape=(batch_size * 1024, ),
needs_grad=True)
self.ts_fields = ti.field(dtype=data_type,
shape=(batch_size * 1024, ),
needs_grad=True)
self.ws_fields = ti.field(dtype=data_type,
shape=(batch_size * 1024, ),
needs_grad=True)
self.T = ti.field(dtype=data_type,
shape=(batch_size * 1024),
needs_grad=True)
# rays level
self.rays_a_fields = ti.field(dtype=ti.i64, shape=(batch_size, 3))
self.total_samples_fields = ti.field(dtype=ti.i64,
shape=(batch_size, ))
self.opacity_fields = ti.field(dtype=data_type,
shape=(batch_size, ),
needs_grad=True)
self.depth_fields = ti.field(dtype=data_type,
shape=(batch_size, ),
needs_grad=True)
self.rgb_fields = ti.field(dtype=data_type,
shape=(batch_size, 3),
needs_grad=True)
# preallocate tensor
self.register_buffer('total_samples',
torch.zeros(batch_size, dtype=torch.int64))
self.register_buffer('rgb', torch.zeros(batch_size,
3,
dtype=torch_type))
self.register_buffer('opacity',
torch.zeros(batch_size, dtype=torch_type))
self.register_buffer('depth', torch.zeros(batch_size,
dtype=torch_type))
self.register_buffer('ws',
torch.zeros(batch_size * 1024, dtype=torch_type))
self.register_buffer('sigma_grad',
torch.zeros(batch_size * 1024, dtype=torch_type))
self.register_buffer(
'rgb_grad', torch.zeros(batch_size * 1024, 3, dtype=torch_type))
class _module_function(torch.autograd.Function):
@staticmethod
@custom_fwd(cast_inputs=torch_type)
def forward(ctx, sigmas, rgbs, deltas, ts, rays_a, T_threshold):
# If no output gradient is provided, no need to
# automatically materialize it as torch.zeros.
ctx.T_threshold = T_threshold
ctx.samples_size = sigmas.shape[0]
ws = self.ws[:sigmas.shape[0]]
torch2ti(self.sigmas_fields, sigmas.contiguous())
torch2ti(self.rgbs_fields, rgbs.contiguous())
torch2ti(self.deltas_fields, deltas.contiguous())
torch2ti(self.ts_fields, ts.contiguous())
torch2ti(self.rays_a_fields, rays_a.contiguous())
composite_train_fw(self.sigmas_fields, self.rgbs_fields,
self.deltas_fields, self.ts_fields,
self.rays_a_fields, T_threshold, self.T,
self.total_samples_fields,
self.opacity_fields, self.depth_fields,
self.rgb_fields, self.ws_fields)
ti2torch(self.total_samples_fields, self.total_samples)
ti2torch(self.opacity_fields, self.opacity)
ti2torch(self.depth_fields, self.depth)
ti2torch(self.rgb_fields, self.rgb)
return self.total_samples.sum(
), self.opacity, self.depth, self.rgb, ws
@staticmethod
@custom_bwd
def backward(ctx, dL_dtotal_samples, dL_dopacity, dL_ddepth,
dL_drgb, dL_dws):
T_threshold = ctx.T_threshold
samples_size = ctx.samples_size
sigma_grad = self.sigma_grad[:samples_size].contiguous()
rgb_grad = self.rgb_grad[:samples_size].contiguous()
self.zero_grad()
torch2ti_grad(self.opacity_fields, dL_dopacity.contiguous())
torch2ti_grad(self.depth_fields, dL_ddepth.contiguous())
torch2ti_grad(self.rgb_fields, dL_drgb.contiguous())
torch2ti_grad(self.ws_fields, dL_dws.contiguous())
composite_train_fw.grad(self.sigmas_fields, self.rgbs_fields,
self.deltas_fields, self.ts_fields,
self.rays_a_fields, T_threshold,
self.T, self.total_samples_fields,
self.opacity_fields, self.depth_fields,
self.rgb_fields, self.ws_fields)
ti2torch_grad(self.sigmas_fields, sigma_grad)
ti2torch_grad(self.rgbs_fields, rgb_grad)
return sigma_grad, rgb_grad, None, None, None, None
self._module_function = _module_function
def zero_grad(self):
self.sigmas_fields.grad.fill(0.)
self.rgbs_fields.grad.fill(0.)
self.T.grad.fill(0.)
def forward(self, sigmas, rgbs, deltas, ts, rays_a, T_threshold):
return self._module_function.apply(sigmas, rgbs, deltas, ts, rays_a,
T_threshold)