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
|
//
// Simple wavefront .obj writer
//
#include "obj_writer.h"
#include <cstdio>
static std::string GetFileBasename(const std::string& FileName)
{
if(FileName.find_last_of(".") != std::string::npos)
return FileName.substr(0, FileName.find_last_of("."));
return "";
}
bool WriteMat(const std::string& filename, const std::vector<tinyobj::material_t>& materials) {
FILE* fp = fopen(filename.c_str(), "w");
if (!fp) {
fprintf(stderr, "Failed to open file [ %s ] for write.\n", filename.c_str());
return false;
}
for (size_t i = 0; i < materials.size(); i++) {
tinyobj::material_t mat = materials[i];
fprintf(fp, "newmtl %s\n", mat.name.c_str());
fprintf(fp, "Ka %f %f %f\n", mat.ambient[0], mat.ambient[1], mat.ambient[2]);
fprintf(fp, "Kd %f %f %f\n", mat.diffuse[0], mat.diffuse[1], mat.diffuse[2]);
fprintf(fp, "Ks %f %f %f\n", mat.specular[0], mat.specular[1], mat.specular[2]);
fprintf(fp, "Kt %f %f %f\n", mat.transmittance[0], mat.specular[1], mat.specular[2]);
fprintf(fp, "Ke %f %f %f\n", mat.emission[0], mat.emission[1], mat.emission[2]);
fprintf(fp, "Ns %f\n", mat.shininess);
fprintf(fp, "Ni %f\n", mat.ior);
// @todo { texture }
}
fclose(fp);
return true;
}
bool WriteObj(const std::string& filename, const std::vector<tinyobj::shape_t>& shapes, const std::vector<tinyobj::material_t>& materials, bool coordTransform) {
FILE* fp = fopen(filename.c_str(), "w");
if (!fp) {
fprintf(stderr, "Failed to open file [ %s ] for write.\n", filename.c_str());
return false;
}
std::string basename = GetFileBasename(filename);
std::string material_filename = basename + ".mtl";
int v_offset = 0;
int vn_offset = 0;
int vt_offset = 0;
int prev_material_id = -1;
fprintf(fp, "mtllib %s\n", material_filename.c_str());
for (size_t i = 0; i < shapes.size(); i++) {
bool has_vn = false;
bool has_vt = false;
if (shapes[i].name.empty()) {
fprintf(fp, "g Unknown\n");
} else {
fprintf(fp, "g %s\n", shapes[i].name.c_str());
}
//if (!shapes[i].material.name.empty()) {
// fprintf(fp, "usemtl %s\n", shapes[i].material.name.c_str());
//}
// facevarying vtx
for (size_t k = 0; k < shapes[i].mesh.indices.size() / 3; k++) {
for (int j = 0; j < 3; j++) {
int idx = shapes[i].mesh.indices[3*k+j];
if (coordTransform) {
fprintf(fp, "v %f %f %f\n",
shapes[i].mesh.positions[3*idx+0],
shapes[i].mesh.positions[3*idx+2],
-shapes[i].mesh.positions[3*idx+1]);
} else {
fprintf(fp, "v %f %f %f\n",
shapes[i].mesh.positions[3*idx+0],
shapes[i].mesh.positions[3*idx+1],
shapes[i].mesh.positions[3*idx+2]);
}
}
}
// facevarying normal
if (shapes[i].mesh.normals.size() > 0) {
for (size_t k = 0; k < shapes[i].mesh.indices.size() / 3; k++) {
for (int j = 0; j < 3; j++) {
int idx = shapes[i].mesh.indices[3*k+j];
if (coordTransform) {
fprintf(fp, "vn %f %f %f\n",
shapes[i].mesh.normals[3*idx+0],
shapes[i].mesh.normals[3*idx+2],
-shapes[i].mesh.normals[3*idx+1]);
} else {
fprintf(fp, "vn %f %f %f\n",
shapes[i].mesh.normals[3*idx+0],
shapes[i].mesh.normals[3*idx+1],
shapes[i].mesh.normals[3*idx+2]);
}
}
}
}
if (shapes[i].mesh.normals.size() > 0) has_vn = true;
// facevarying texcoord
if (shapes[i].mesh.texcoords.size() > 0) {
for (size_t k = 0; k < shapes[i].mesh.indices.size() / 3; k++) {
for (int j = 0; j < 3; j++) {
int idx = shapes[i].mesh.indices[3*k+j];
fprintf(fp, "vt %f %f\n",
shapes[i].mesh.texcoords[2*idx+0],
shapes[i].mesh.texcoords[2*idx+1]);
}
}
}
if (shapes[i].mesh.texcoords.size() > 0) has_vt = true;
// face
for (size_t k = 0; k < shapes[i].mesh.indices.size() / 3; k++) {
// Face index is 1-base.
//int v0 = shapes[i].mesh.indices[3*k+0] + 1 + v_offset;
//int v1 = shapes[i].mesh.indices[3*k+1] + 1 + v_offset;
//int v2 = shapes[i].mesh.indices[3*k+2] + 1 + v_offset;
int v0 = (3*k + 0) + 1 + v_offset;
int v1 = (3*k + 1) + 1 + v_offset;
int v2 = (3*k + 2) + 1 + v_offset;
int vt0 = (3*k + 0) + 1 + vt_offset;
int vt1 = (3*k + 1) + 1 + vt_offset;
int vt2 = (3*k + 2) + 1 + vt_offset;
int material_id = shapes[i].mesh.material_ids[k];
if (material_id != prev_material_id) {
std::string material_name = materials[material_id].name;
fprintf(fp, "usemtl %s\n", material_name.c_str());
prev_material_id = material_id;
}
if (has_vn && has_vt) {
fprintf(fp, "f %d/%d/%d %d/%d/%d %d/%d/%d\n",
v0, vt0, v0, v1, vt1, v1, v2, vt2, v2);
} else if (has_vn && !has_vt) {
fprintf(fp, "f %d//%d %d//%d %d//%d\n", v0, v0, v1, v1, v2, v2);
} else if (!has_vn && has_vt) {
fprintf(fp, "f %d/%d %d/%d %d/%d\n", v0, v0, v1, v1, v2, v2);
} else {
fprintf(fp, "f %d %d %d\n", v0, v1, v2);
}
}
v_offset += shapes[i].mesh.indices.size();
//vn_offset += shapes[i].mesh.normals.size() / 3;
vt_offset += shapes[i].mesh.texcoords.size() / 2;
}
fclose(fp);
//
// Write material file
//
bool ret = WriteMat(material_filename, materials);
return ret;
}
|
