File size: 21,644 Bytes
cacb27a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.

# This source code is licensed under the license found in the
# LICENSE file in the root directory of this source tree.
# --------------------------------------------------------
# References:
# DeiT: https://github.com/facebookresearch/deit
# BEiT: https://github.com/microsoft/unilm/tree/master/beit
# MAE: https://github.com/facebookresearch/mae
# --------------------------------------------------------
import math
from typing import Iterable
import os
import matplotlib.pyplot as plt
import random
import torch
import numpy as np
import time
import base64
from io import BytesIO

import util.misc as misc
import util.lr_sched as lr_sched

from pytorch3d.structures import Pointclouds
from pytorch3d.vis.plotly_vis import plot_scene
from pytorch3d.transforms import RotateAxisAngle
from pytorch3d.io import IO


def evaluate_points(predicted_xyz, gt_xyz, dist_thres):
    if predicted_xyz.shape[0] == 0:
        return 0.0, 0.0, 0.0
    slice_size = 1000
    precision = 0.0
    for i in range(int(np.ceil(predicted_xyz.shape[0] / slice_size))):
        start = slice_size * i
        end   = slice_size * (i + 1)
        dist = ((predicted_xyz[start:end, None] - gt_xyz[None]) ** 2.0).sum(axis=-1) ** 0.5
        precision += ((dist < dist_thres).sum(axis=1) > 0).sum()
    precision /= predicted_xyz.shape[0]

    recall = 0.0
    for i in range(int(np.ceil(predicted_xyz.shape[0] / slice_size))):
        start = slice_size * i
        end   = slice_size * (i + 1)
        dist = ((predicted_xyz[:, None] - gt_xyz[None, start:end]) ** 2.0).sum(axis=-1) ** 0.5
        recall += ((dist < dist_thres).sum(axis=0) > 0).sum()
    recall /= gt_xyz.shape[0]
    return precision, recall, get_f1(precision, recall)

def aug_xyz(seen_xyz, unseen_xyz, args, is_train):
    degree_x = 0
    degree_y = 0
    degree_z = 0
    if is_train:
        r_delta = args.random_scale_delta
        scale = torch.tensor([
            random.uniform(1.0 - r_delta, 1.0 + r_delta),
            random.uniform(1.0 - r_delta, 1.0 + r_delta),
            random.uniform(1.0 - r_delta, 1.0 + r_delta),
        ], device=seen_xyz.device)

        if args.use_hypersim:
            shift = 0
        else:
            degree_x = random.randrange(-args.random_rotate_degree, args.random_rotate_degree + 1)
            degree_y = random.randrange(-args.random_rotate_degree, args.random_rotate_degree + 1)
            degree_z = random.randrange(-args.random_rotate_degree, args.random_rotate_degree + 1)

            r_shift = args.random_shift
            shift = torch.tensor([[[
                random.uniform(-r_shift, r_shift),
                random.uniform(-r_shift, r_shift),
                random.uniform(-r_shift, r_shift),
            ]]], device=seen_xyz.device)
        seen_xyz = seen_xyz * scale + shift
        unseen_xyz = unseen_xyz * scale + shift

    B, H, W, _ = seen_xyz.shape
    return [
        rotate(seen_xyz.reshape((B, -1, 3)), degree_x, degree_y, degree_z).reshape((B, H, W, 3)),
        rotate(unseen_xyz, degree_x, degree_y, degree_z),
    ]


def rotate(sample, degree_x, degree_y, degree_z):
    for degree, axis in [(degree_x, "X"), (degree_y, "Y"), (degree_z, "Z")]:
        if degree != 0:
            sample = RotateAxisAngle(degree, axis=axis).to(sample.device).transform_points(sample)
    return sample


def get_grid(B, device, co3d_world_size, granularity):
    N = int(np.ceil(2 * co3d_world_size / granularity))
    grid_unseen_xyz = torch.zeros((N, N, N, 3), device=device)
    for i in range(N):
        grid_unseen_xyz[i, :, :, 0] = i
    for j in range(N):
        grid_unseen_xyz[:, j, :, 1] = j
    for k in range(N):
        grid_unseen_xyz[:, :, k, 2] = k
    grid_unseen_xyz -= (N / 2.0)
    grid_unseen_xyz /= (N / 2.0) / co3d_world_size
    grid_unseen_xyz = grid_unseen_xyz.reshape((1, -1, 3)).repeat(B, 1, 1)
    return grid_unseen_xyz


def run_viz(model, data_loader, device, args, epoch):
    epoch_start_time = time.time()
    model.eval()
    os.system(f'mkdir {args.job_dir}/viz')

    print('Visualization data_loader length:', len(data_loader))
    dataset = data_loader.dataset
    for sample_idx, samples in enumerate(data_loader):
        if sample_idx >= args.max_n_viz_obj:
            break
        seen_xyz, valid_seen_xyz, unseen_xyz, unseen_rgb, labels, seen_images = prepare_data(samples, device, is_train=False, args=args, is_viz=True)

        pred_occupy = []
        pred_colors = []
        (model.module if hasattr(model, "module") else model).clear_cache()

        # don't forward all at once to avoid oom
        max_n_queries_fwd = 2000

        total_n_passes = int(np.ceil(unseen_xyz.shape[1] / max_n_queries_fwd))
        for p_idx in range(total_n_passes):
            p_start = p_idx     * max_n_queries_fwd
            p_end = (p_idx + 1) * max_n_queries_fwd
            cur_unseen_xyz = unseen_xyz[:, p_start:p_end]
            cur_unseen_rgb = unseen_rgb[:, p_start:p_end].zero_()
            cur_labels = labels[:, p_start:p_end].zero_()

            with torch.no_grad():
                _, pred, = model(
                    seen_images=seen_images,
                    seen_xyz=seen_xyz,
                    unseen_xyz=cur_unseen_xyz,
                    unseen_rgb=cur_unseen_rgb,
                    unseen_occupy=cur_labels,
                    cache_enc=args.run_viz,
                    valid_seen_xyz=valid_seen_xyz,
                )

            cur_occupy_out = pred[..., 0]

            if args.regress_color:
                cur_color_out = pred[..., 1:].reshape((-1, 3))
            else:
                cur_color_out = pred[..., 1:].reshape((-1, 3, 256)).max(dim=2)[1] / 255.0
            pred_occupy.append(cur_occupy_out)
            pred_colors.append(cur_color_out)

        rank = misc.get_rank()
        prefix = f'{args.job_dir}/viz/' + dataset.dataset_split + f'_ep{epoch}_rank{rank}_i{sample_idx}'

        img = (seen_images[0].permute(1, 2, 0) * 255).cpu().numpy().copy().astype(np.uint8)

        gt_xyz = samples[1][0].to(device).reshape(-1, 3)
        gt_rgb = samples[1][1].to(device).reshape(-1, 3)
        mesh_xyz = samples[2].to(device).reshape(-1, 3) if args.use_hypersim else None

        with open(prefix + '.html', 'a') as f:
            generate_html(
                img,
                seen_xyz, seen_images,
                torch.cat(pred_occupy, dim=1),
                torch.cat(pred_colors, dim=0),
                unseen_xyz,
                f,
                gt_xyz=gt_xyz,
                gt_rgb=gt_rgb,
                mesh_xyz=mesh_xyz,
            )
    print("Visualization epoch time:", time.time() - epoch_start_time)


def get_f1(precision, recall):
    if (precision + recall) == 0:
        return 0.0
    return 2.0 * precision * recall / (precision + recall)


def generate_plot(img, seen_xyz, seen_rgb, pred_occ, pred_rgb, unseen_xyz,
        gt_xyz=None, gt_rgb=None, mesh_xyz=None, score_thresholds=[0.1, 0.3, 0.5, 0.7, 0.9],
        pointcloud_marker_size=2,
    ):
    # if img is not None:
    #     fig = plt.figure()
    #     plt.imshow(img)
    #     tmpfile = BytesIO()
    #     fig.savefig(tmpfile, format='jpg')
    #     encoded = base64.b64encode(tmpfile.getvalue()).decode('utf-8')

    #     html = '<img src=\'data:image/png;base64,{}\'>'.format(encoded)
    #     f.write(html)
    #     plt.close()

    clouds = {"MCC Output": {}}
    # Seen
    if seen_xyz is not None:
        seen_xyz = seen_xyz.reshape((-1, 3)).cpu()
        seen_rgb = torch.nn.functional.interpolate(seen_rgb, (112, 112)).permute(0, 2, 3, 1).reshape((-1, 3)).cpu()
        good_seen = seen_xyz[:, 0] != -100

        seen_pc = Pointclouds(
            points=seen_xyz[good_seen][None],
            features=seen_rgb[good_seen][None],
        )
        clouds["MCC Output"]["seen"] = seen_pc

    # GT points
    if gt_xyz is not None:
        subset_gt = random.sample(range(gt_xyz.shape[0]), 10000)
        gt_pc = Pointclouds(
            points=gt_xyz[subset_gt][None],
            features=gt_rgb[subset_gt][None],
        )
        clouds["MCC Output"]["GT points"] = gt_pc

    # GT meshes
    if mesh_xyz is not None:
        subset_mesh = random.sample(range(mesh_xyz.shape[0]), 10000)
        mesh_pc = Pointclouds(
            points=mesh_xyz[subset_mesh][None],
        )
        clouds["MCC Output"]["GT mesh"] = mesh_pc

    pred_occ = torch.nn.Sigmoid()(pred_occ).cpu()
    for t in score_thresholds:
        pos = pred_occ > t

        points = unseen_xyz[pos].reshape((-1, 3))
        features = pred_rgb[None][pos].reshape((-1, 3))
        good_points = points[:, 0] != -100

        if good_points.sum() == 0:
            continue

        pc = Pointclouds(
            points=points[good_points][None].cpu(),
            features=features[good_points][None].cpu(),
        )

        clouds["MCC Output"][f"pred_{t}"] = pc
        IO().save_pointcloud(pc, "output_pointcloud.ply")

    plt.figure()
    try:
        fig = plot_scene(clouds, pointcloud_marker_size=pointcloud_marker_size, pointcloud_max_points=20000 * 2)
        fig.update_layout(height=1000, width=1000)
        return fig
    except Exception as e:
        print('writing failed', e)
    try:
        plt.close()
    except:
        pass


def generate_html(img, seen_xyz, seen_rgb, pred_occ, pred_rgb, unseen_xyz, f,
        gt_xyz=None, gt_rgb=None, mesh_xyz=None, score_thresholds=[0.1, 0.3, 0.5, 0.7, 0.9],
        pointcloud_marker_size=2,
    ):
    if img is not None:
        fig = plt.figure()
        plt.imshow(img)
        tmpfile = BytesIO()
        fig.savefig(tmpfile, format='jpg')
        encoded = base64.b64encode(tmpfile.getvalue()).decode('utf-8')

        html = '<img src=\'data:image/png;base64,{}\'>'.format(encoded)
        f.write(html)
        plt.close()

    clouds = {"MCC Output": {}}
    # Seen
    if seen_xyz is not None:
        seen_xyz = seen_xyz.reshape((-1, 3)).cpu()
        seen_rgb = torch.nn.functional.interpolate(seen_rgb, (112, 112)).permute(0, 2, 3, 1).reshape((-1, 3)).cpu()
        good_seen = seen_xyz[:, 0] != -100

        seen_pc = Pointclouds(
            points=seen_xyz[good_seen][None],
            features=seen_rgb[good_seen][None],
        )
        clouds["MCC Output"]["seen"] = seen_pc

    # GT points
    if gt_xyz is not None:
        subset_gt = random.sample(range(gt_xyz.shape[0]), 10000)
        gt_pc = Pointclouds(
            points=gt_xyz[subset_gt][None],
            features=gt_rgb[subset_gt][None],
        )
        clouds["MCC Output"]["GT points"] = gt_pc

    # GT meshes
    if mesh_xyz is not None:
        subset_mesh = random.sample(range(mesh_xyz.shape[0]), 10000)
        mesh_pc = Pointclouds(
            points=mesh_xyz[subset_mesh][None],
        )
        clouds["MCC Output"]["GT mesh"] = mesh_pc

    pred_occ = torch.nn.Sigmoid()(pred_occ).cpu()
    for t in score_thresholds:
        pos = pred_occ > t

        points = unseen_xyz[pos].reshape((-1, 3))
        features = pred_rgb[None][pos].reshape((-1, 3))
        good_points = points[:, 0] != -100

        if good_points.sum() == 0:
            continue

        pc = Pointclouds(
            points=points[good_points][None].cpu(),
            features=features[good_points][None].cpu(),
        )

        clouds["MCC Output"][f"pred_{t}"] = pc

    plt.figure()
    try:
        fig = plot_scene(clouds, pointcloud_marker_size=pointcloud_marker_size, pointcloud_max_points=20000 * 2)
        fig.update_layout(height=1000, width=1000)
        html_string = fig.to_html(full_html=False, include_plotlyjs="cnd")
        f.write(html_string)
        return fig, plt
    except Exception as e:
        print('writing failed', e)
    try:
        plt.close()
    except:
        pass


def train_one_epoch(model: torch.nn.Module,
                    data_loader: Iterable, optimizer: torch.optim.Optimizer,
                    device: torch.device, epoch: int, loss_scaler,
                    args=None):
    epoch_start_time = time.time()
    model.train(True)
    metric_logger = misc.MetricLogger(delimiter="  ")
    metric_logger.add_meter('lr', misc.SmoothedValue(window_size=1, fmt='{value:.6f}'))

    accum_iter = args.accum_iter

    optimizer.zero_grad()

    print('Training data_loader length:', len(data_loader))
    for data_iter_step, samples in enumerate(data_loader):
        # we use a per iteration (instead of per epoch) lr scheduler
        if data_iter_step % accum_iter == 0:
            lr_sched.adjust_learning_rate(optimizer, data_iter_step / len(data_loader) + epoch, args)
        seen_xyz, valid_seen_xyz, unseen_xyz, unseen_rgb, labels, seen_images = prepare_data(samples, device, is_train=True, args=args)

        with torch.cuda.amp.autocast():
            loss, _ = model(
                seen_images=seen_images,
                seen_xyz=seen_xyz,
                unseen_xyz=unseen_xyz,
                unseen_rgb=unseen_rgb,
                unseen_occupy=labels,
                valid_seen_xyz=valid_seen_xyz,
            )

        loss_value = loss.item()
        if not math.isfinite(loss_value):
            print("Warning: Loss is {}".format(loss_value))
            loss *= 0.0
            loss_value = 100.0

        loss /= accum_iter
        loss_scaler(loss, optimizer, parameters=model.parameters(),
                    clip_grad=args.clip_grad,
                    update_grad=(data_iter_step + 1) % accum_iter == 0,
                    verbose=(data_iter_step % 100) == 0)

        if (data_iter_step + 1) % accum_iter == 0:
            optimizer.zero_grad()

        torch.cuda.synchronize()

        metric_logger.update(loss=loss_value)

        lr = optimizer.param_groups[0]["lr"]
        metric_logger.update(lr=lr)

        if data_iter_step == 30:
            os.system('nvidia-smi')
            os.system('free -g')
        if args.debug and data_iter_step == 5:
            break

    # gather the stats from all processes
    metric_logger.synchronize_between_processes()
    print("Averaged stats:", metric_logger)
    print("Training epoch time:", time.time() - epoch_start_time)
    return {k: meter.global_avg for k, meter in metric_logger.meters.items()}


def eval_one_epoch(
        model: torch.nn.Module,
        data_loader: Iterable,
        device: torch.device,
        args=None
    ):
    epoch_start_time = time.time()
    model.train(False)

    metric_logger = misc.MetricLogger(delimiter="  ")

    print('Eval len(data_loader):', len(data_loader))

    for data_iter_step, samples in enumerate(data_loader):
        seen_xyz, valid_seen_xyz, unseen_xyz, unseen_rgb, labels, seen_images = prepare_data(samples, device, is_train=False, args=args)

        # don't forward all at once to avoid oom
        max_n_queries_fwd = 5000
        all_loss, all_preds = [], []
        for p_idx in range(int(np.ceil(unseen_xyz.shape[1] / max_n_queries_fwd))):
            p_start = p_idx     * max_n_queries_fwd
            p_end = (p_idx + 1) * max_n_queries_fwd
            cur_unseen_xyz = unseen_xyz[:, p_start:p_end]
            cur_unseen_rgb = unseen_rgb[:, p_start:p_end]
            cur_labels = labels[:, p_start:p_end]

            with torch.no_grad():
                loss, pred = model(
                    seen_images=seen_images,
                    seen_xyz=seen_xyz,
                    unseen_xyz=cur_unseen_xyz,
                    unseen_rgb=cur_unseen_rgb,
                    unseen_occupy=cur_labels,
                    valid_seen_xyz=valid_seen_xyz,
                )
            all_loss.append(loss)
            all_preds.append(pred)

        loss = sum(all_loss) / len(all_loss)
        pred = torch.cat(all_preds, dim=1)

        B = pred.shape[0]

        gt_xyz = samples[1][0].to(device).reshape((B, -1, 3))
        if args.use_hypersim:
            mesh_xyz = samples[2].to(device).reshape((B, -1, 3))

        s_thres = args.eval_score_threshold
        d_thres = args.eval_dist_threshold

        for b_idx in range(B):
            geometry_metrics = {}
            predicted_idx = torch.nn.Sigmoid()(pred[b_idx, :, 0]) > s_thres
            predicted_xyz = unseen_xyz[b_idx, predicted_idx]

            precision, recall, f1 = evaluate_points(predicted_xyz, gt_xyz[b_idx], d_thres)
            geometry_metrics[f'd{d_thres}_s{s_thres}_point_pr'] = precision
            geometry_metrics[f'd{d_thres}_s{s_thres}_point_rc'] = recall
            geometry_metrics[f'd{d_thres}_s{s_thres}_point_f1'] = f1

            if args.use_hypersim:
                precision, recall, f1 = evaluate_points(predicted_xyz, mesh_xyz[b_idx], d_thres)
                geometry_metrics[f'd{d_thres}_s{s_thres}_mesh_pr'] = precision
                geometry_metrics[f'd{d_thres}_s{s_thres}_mesh_rc'] = recall
                geometry_metrics[f'd{d_thres}_s{s_thres}_mesh_f1'] = f1

            metric_logger.update(**geometry_metrics)

        loss_value = loss.item()

        torch.cuda.synchronize()
        metric_logger.update(loss=loss_value)

        if args.debug and data_iter_step == 5:
            break

    metric_logger.synchronize_between_processes()
    print("Validation averaged stats:", metric_logger)
    print("Val epoch time:", time.time() - epoch_start_time)
    return {k: meter.global_avg for k, meter in metric_logger.meters.items()}


def sample_uniform_semisphere(B, N, semisphere_size, device):
    for _ in range(100):
        points = torch.empty(B * N * 3, 3, device=device).uniform_(-semisphere_size, semisphere_size)
        points[..., 2] = points[..., 2].abs()
        dist = (points ** 2.0).sum(axis=-1) ** 0.5
        if (dist < semisphere_size).sum() >= B * N:
            return points[dist < semisphere_size][:B * N].reshape((B, N, 3))
        else:
            print('resampling sphere')


def get_grid_semisphere(B, granularity, semisphere_size, device):
    n_grid_pts = int(semisphere_size / granularity) * 2 + 1
    grid_unseen_xyz = torch.zeros((n_grid_pts, n_grid_pts, n_grid_pts // 2 + 1, 3), device=device)
    for i in range(n_grid_pts):
        grid_unseen_xyz[i, :, :, 0] = i
        grid_unseen_xyz[:, i, :, 1] = i
    for i in range(n_grid_pts // 2 + 1):
        grid_unseen_xyz[:, :, i, 2] = i
    grid_unseen_xyz[..., :2] -= (n_grid_pts // 2.0)
    grid_unseen_xyz *= granularity
    dist = (grid_unseen_xyz ** 2.0).sum(axis=-1) ** 0.5
    grid_unseen_xyz = grid_unseen_xyz[dist <= semisphere_size]
    return grid_unseen_xyz[None].repeat(B, 1, 1)


def get_min_dist(a, b, slice_size=1000):
    all_min, all_idx = [], []
    for i in range(int(np.ceil(a.shape[1] / slice_size))):
        start = slice_size * i
        end   = slice_size * (i + 1)
        # B, n_queries, n_gt
        dist = ((a[:, start:end] - b) ** 2.0).sum(axis=-1) ** 0.5
        # B, n_queries
        cur_min, cur_idx = dist.min(axis=2)
        all_min.append(cur_min)
        all_idx.append(cur_idx)
    return torch.cat(all_min, dim=1), torch.cat(all_idx, dim=1)


def construct_uniform_semisphere(gt_xyz, gt_rgb, semisphere_size, n_queries, dist_threshold, is_train, granularity):
    B = gt_xyz.shape[0]
    device = gt_xyz.device
    if is_train:
        unseen_xyz = sample_uniform_semisphere(B, n_queries, semisphere_size, device)
    else:
        unseen_xyz = get_grid_semisphere(B, granularity, semisphere_size, device)
    dist, idx_to_gt = get_min_dist(unseen_xyz[:, :, None], gt_xyz[:, None])
    labels = dist < dist_threshold
    unseen_rgb = torch.zeros_like(unseen_xyz)
    unseen_rgb[labels] = torch.gather(gt_rgb, 1, idx_to_gt.unsqueeze(-1).repeat(1, 1, 3))[labels]
    return unseen_xyz, unseen_rgb, labels.float()


def construct_uniform_grid(gt_xyz, gt_rgb, co3d_world_size, n_queries, dist_threshold, is_train, granularity):
    B = gt_xyz.shape[0]
    device = gt_xyz.device
    if is_train:
        unseen_xyz = torch.empty((B, n_queries, 3), device=device).uniform_(-co3d_world_size, co3d_world_size)
    else:
        unseen_xyz = get_grid(B, device, co3d_world_size, granularity)
    dist, idx_to_gt = get_min_dist(unseen_xyz[:, :, None], gt_xyz[:, None])
    labels = dist < dist_threshold
    unseen_rgb = torch.zeros_like(unseen_xyz)
    unseen_rgb[labels] = torch.gather(gt_rgb, 1, idx_to_gt.unsqueeze(-1).repeat(1, 1, 3))[labels]
    return unseen_xyz, unseen_rgb, labels.float()


def prepare_data(samples, device, is_train, args, is_viz=False):
    # Seen
    seen_xyz, seen_rgb = samples[0][0].to(device), samples[0][1].to(device)
    valid_seen_xyz = torch.isfinite(seen_xyz.sum(axis=-1))
    seen_xyz[~valid_seen_xyz] = -100
    B = seen_xyz.shape[0]
    # Gt
    gt_xyz, gt_rgb = samples[1][0].to(device).reshape(B, -1, 3), samples[1][1].to(device).reshape(B, -1, 3)

    sampling_func = construct_uniform_semisphere if args.use_hypersim else construct_uniform_grid
    unseen_xyz, unseen_rgb, labels = sampling_func(
        gt_xyz, gt_rgb,
        args.semisphere_size if args.use_hypersim else args.co3d_world_size,
        args.n_queries,
        args.train_dist_threshold,
        is_train,
        args.viz_granularity if is_viz else args.eval_granularity,
    )

    if is_train:
        seen_xyz, unseen_xyz = aug_xyz(seen_xyz, unseen_xyz, args, is_train=is_train)

        # Random Flip
        if random.random() < 0.5:
            seen_xyz[..., 0] *= -1
            unseen_xyz[..., 0] *= -1
            seen_xyz = torch.flip(seen_xyz, [2])
            valid_seen_xyz = torch.flip(valid_seen_xyz, [2])
            seen_rgb = torch.flip(seen_rgb, [3])

    return seen_xyz, valid_seen_xyz, unseen_xyz, unseen_rgb, labels, seen_rgb