File size: 9,768 Bytes
bd13c8d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
"""
Adapted from `360_view.py` & `360_view_test.py` in the original NeRF synthetic
Blender dataset blend-files.
"""
import argparse
import os
import json
from math import radians
import bpy
import numpy as np


COLOR_SPACES = [ "display", "linear" ]
DEVICES = [ "cpu", "cuda", "optix" ]

CIRCLE_FIXED_START = ( 0, 0, 0 )
CIRCLE_FIXED_END = ( .7, 0, 0 )


def listify_matrix(matrix):
    matrix_list = []
    for row in matrix:
        matrix_list.append(list(row))
    return matrix_list


def parent_obj_to_camera(b_camera):
    origin = (0, 0, 0)
    b_empty = bpy.data.objects.new("Empty", None)
    b_empty.location = origin
    b_camera.parent = b_empty  # setup parenting

    scn = bpy.context.scene
    scn.collection.objects.link(b_empty)
    bpy.context.view_layer.objects.active = b_empty

    return b_empty


def main(args):
    # open the scene blend-file
    bpy.ops.wm.open_mainfile(filepath=args.blend_path)

    # initialize render settings
    scene = bpy.data.scenes["Scene"]
    scene.render.engine = "CYCLES"
    scene.render.use_persistent_data = True

    if args.device == "cpu":
        bpy.context.preferences.addons["cycles"].preferences \
           .compute_device_type = "NONE"
        bpy.context.scene.cycles.device = "CPU"
    elif args.device == "cuda":
        bpy.context.preferences.addons["cycles"].preferences \
           .compute_device_type = "CUDA"
        bpy.context.scene.cycles.device = "GPU"
    elif args.device == "optix":
        bpy.context.preferences.addons["cycles"].preferences \
           .compute_device_type = "OPTIX"
        bpy.context.scene.cycles.device = "GPU"
    bpy.context.preferences.addons["cycles"].preferences.get_devices()

    # initialize compositing nodes
    scene.view_layers[0].use_pass_combined = True
    scene.use_nodes = True
    tree = scene.node_tree

    if args.depth:
        scene.view_layers[0].use_pass_z = True
        combine_color = tree.nodes.new("CompositorNodeCombineColor")
        depth_output = tree.nodes.new("CompositorNodeOutputFile")
    if args.normal:
        scene.view_layers[0].use_pass_normal = True
        normal_output = tree.nodes.new("CompositorNodeOutputFile")
    if args.depth or args.normal:
        render_layers = tree.nodes.new("CompositorNodeRLayers")

    # initialize RGB render image output settings
    scene.render.filepath = args.renders_path
    scene.render.use_file_extension = True
    scene.render.use_overwrite = True
    scene.render.image_settings.color_mode = "RGBA"

    if args.color_space == "display":
        scene.render.image_settings.file_format = "PNG"
        scene.render.image_settings.color_depth = "8"
        scene.render.image_settings.color_management = "FOLLOW_SCENE"
    elif args.color_space == "linear":
        scene.render.image_settings.file_format = "OPEN_EXR"
        scene.render.image_settings.color_depth = "32"
        scene.render.image_settings.use_zbuffer = False

    if args.depth:
        # initialize depth render image output settings
        depth_output.base_path = os.path.join(args.renders_path, "depth")
        depth_output.file_slots[0].use_node_format = True
        scene.frame_set(0)

        depth_output.format.file_format = "OPEN_EXR"
        depth_output.format.color_mode = "RGB"
        depth_output.format.color_depth = "32"
        depth_output.format.exr_codec = "NONE"
        depth_output.format.use_zbuffer = False

        # link compositing nodes
        links = tree.links

        # output depth img (RGB img is output via the existing composite node)
        combine_color.mode = "RGB"
        links.new(render_layers.outputs["Depth"], combine_color.inputs["Red"])
        combine_color.inputs["Green"].default_value = 0
        combine_color.inputs["Blue"].default_value = 0
        combine_color.inputs["Alpha"].default_value = 1

        links.new(combine_color.outputs["Image"], depth_output.inputs["Image"])
    
    if args.normal:
        # initialize normal render image output settings
        normal_output.base_path = os.path.join(args.renders_path, "normal")
        normal_output.file_slots[0].use_node_format = True
        scene.frame_set(0)

        normal_output.format.file_format = "OPEN_EXR"
        normal_output.format.color_mode = "RGB"
        normal_output.format.color_depth = "32"
        normal_output.format.exr_codec = "NONE"
        normal_output.format.use_zbuffer = False

        # link compositing nodes
        links = tree.links

        # output normal img (RGB img is output via the existing composite node)
        combine_color.mode = "RGB"
        links.new(render_layers.outputs["Normal"],
                  normal_output.inputs["Image"])

    # initialize camera settings
    scene.render.dither_intensity = 0.0
    scene.render.film_transparent = True
    scene.render.resolution_percentage = 100
    scene.render.resolution_x = args.resolution[0]
    scene.render.resolution_y = args.resolution[1]

    cam = bpy.data.objects["Camera"]
    cam.location = (0, 4.0, 0.5)
    cam.rotation_mode = "XYZ"
    cam_constraint = cam.constraints.new(type="TRACK_TO")
    cam_constraint.track_axis = "TRACK_NEGATIVE_Z"
    cam_constraint.up_axis = "UP_Y"
    b_empty = parent_obj_to_camera(cam)
    cam_constraint.target = b_empty

    # preprocess & derive paths
    args.renders_path = os.path.normpath(args.renders_path)                     # remove trailing slashes
    folder_name = os.path.basename(args.renders_path)
    renders_parent_path = os.path.dirname(args.renders_path)  
    transforms_path = os.path.join(
        renders_parent_path, f"transforms_{folder_name}.json"
    )

    # render novel views
    stepsize = 360.0 / args.num_views
    if not args.random_views:
        vertical_diff = CIRCLE_FIXED_END[0] - CIRCLE_FIXED_START[0]
        b_empty.rotation_euler = CIRCLE_FIXED_START
        b_empty.rotation_euler[0] = CIRCLE_FIXED_START[0] + vertical_diff

    out_data = {
        "camera_angle_x": cam.data.angle_x,
        "frames": []
    }
    for i in range(0, args.num_views):
        if args.random_views:
            if args.upper_views:
                rot = np.random.uniform(0, 1, size=3) * (1,0,2*np.pi)
                rot[0] = np.abs(np.arccos(1 - 2 * rot[0]) - np.pi/2)
                b_empty.rotation_euler = rot
            else:
                b_empty.rotation_euler = np.random.uniform(0, 2*np.pi, size=3)
        else:
            print("Rotation {}, {}".format((stepsize * i), radians(stepsize * i)))
            
        scene.render.filepath = os.path.join(args.renders_path, f"r_{i}")
        if args.depth:
            depth_output.file_slots[0].path = f"r_{i}"
        if args.normal:
            normal_output.file_slots[0].path = f"r_{i}"
        bpy.ops.render.render(write_still=True)

        # remove the "0000" suffix in the depth & normal map filenames
        if args.depth:
            os.rename(os.path.join(depth_output.base_path, f"r_{i}0000.exr"),
                      os.path.join(depth_output.base_path, f"r_{i}.exr"))
        if args.normal:
            os.rename(os.path.join(normal_output.base_path, f"r_{i}0000.exr"),
                      os.path.join(normal_output.base_path, f"r_{i}.exr"))            

        frame_data = {
            "file_path": os.path.join(".", os.path.relpath(
                            scene.render.filepath, start=renders_parent_path
                         )),
            "rotation": radians(stepsize),
            "transform_matrix": listify_matrix(cam.matrix_world)
        }
        out_data["frames"].append(frame_data)

        if args.random_views:
            if args.upper_views:
                rot = np.random.uniform(0, 1, size=3) * (1,0,2*np.pi)
                rot[0] = np.abs(np.arccos(1 - 2 * rot[0]) - np.pi/2)
                b_empty.rotation_euler = rot
            else:
                b_empty.rotation_euler = np.random.uniform(0, 2*np.pi, size=3)
        else:
            b_empty.rotation_euler[0] = (
                CIRCLE_FIXED_START[0]
                + (np.cos(radians(stepsize*i))+1)/2 * vertical_diff
            )
            b_empty.rotation_euler[2] += radians(2*stepsize)

    with open(transforms_path, "w") as out_file:
        json.dump(out_data, out_file, indent=4)


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description=("Script for rendering novel views of"
                     " synthetic Blender scenes.")
    )
    parser.add_argument(
        "blend_path", type=str,
        help="Path to the blend-file of the synthetic Blender scene."
    )
    parser.add_argument(
        "renders_path", type=str,
        help="Desired path to the novel view renders."
    )
    parser.add_argument(
        "num_views", type=int,
        help="Number of novel view renders."
    )
    parser.add_argument(
        "resolution", type=int, nargs=2,
        help="Image resolution of the novel view renders."
    )
    parser.add_argument(
        "--color_space", type=str, choices=COLOR_SPACES, default="display",
        help="Color space of the output novel view images."
    )
    parser.add_argument(
        "--device", type=str, choices=DEVICES, default="cpu",
        help="Compute device type for rendering."
    )
    parser.add_argument(
        "--random_views", action="store_true",
        help="Randomly sample novel views."
    )
    parser.add_argument(
        "--upper_views", action="store_true",
        help="Only sample novel views from the upper hemisphere."
    )
    parser.add_argument(
        "--depth", action="store_true",
        help="Render depth maps too."
    )
    parser.add_argument(
        "--normal", action="store_true",
        help="Render normal maps too."
    )
    args = parser.parse_args()

    main(args)