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
|
#include "../include/ModelLoader.hpp"
#include "../include/File.hpp"
#include "../include/Image.hpp"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include <libgen.h>
#include <string>
namespace amalgine {
class ModelLoaderInternal {
public:
ModelLoaderInternal(const char *data, size_t size) : data(data), size(size), offset(0) {}
template <typename T>
bool extract(T *result) {
if(size - offset >= sizeof(T)) {
// This is fine, because all data in .a3d files are aligned correctly.
// However this could be incorrect if the file is not an .a3d file, in which case this would crash on ARM processors for example..
// TODO: Use memcpy on ARM (and other platforms that dont support unaligned memory access)
*result = *(T*)(data + offset);
offset += sizeof(T);
return true;
} else {
return false;
}
}
template <typename T>
bool extract_list(T *result, size_t num_items) {
const size_t bytes_to_extract = sizeof(T) * num_items;
if(size - offset >= bytes_to_extract) {
memcpy(result, data + offset, bytes_to_extract);
offset += bytes_to_extract;
return true;
} else {
return false;
}
}
std::string extract_null_terminated_string() {
std::string result;
const char *p = data + offset;
while(true) {
char c = *p++;
if(c == '\0')
break;
else
result += c;
}
offset += p - (data + offset);
return result;
}
bool skip(size_t num_bytes) {
if(size - offset >= num_bytes) {
offset += num_bytes;
return true;
} else {
return false;
}
}
bool empty() const { return offset == size; }
private:
const char *data;
const size_t size;
size_t offset;
};
struct Face {
unsigned int index[3];
};
// TODO: Check bounds of indices and size of data before allocating
static bool model_loader_version_1(ModelLoaderInternal &model_loader, std::vector<Triangle3D> &triangles, std::vector<vec2f> &texture_coords, Image **image, const std::string &dir_path) {
// TODO: Remove these temporary variables when amalgine has been modified to use indices instead of
// data directly in shaders
std::vector<Triangle3D> temp_vertices;
std::vector<vec2f> temp_texcoords;
std::vector<Face> indices;
while(!model_loader.empty()) {
// TODO: Verify num_vertices isn't too large?
unsigned int num_vertices;
if(!model_loader.extract<unsigned int>(&num_vertices) || num_vertices == 0) {
fprintf(stderr, "Error: failed to extract num_vertices\n");
return false;
}
unsigned int num_triangles = num_vertices / 3;
temp_vertices.resize(num_triangles);
if(!model_loader.extract_list(&temp_vertices[0], num_triangles)) {
fprintf(stderr, "Error: failed to extract vertices\n");
return false;
}
if(!model_loader.skip(num_vertices * sizeof(vec3f))) {
fprintf(stderr, "Error: failed to extract normals\n");
return false;
}
unsigned int has_texcoords;
if(!model_loader.extract<unsigned int>(&has_texcoords) || has_texcoords > 1) {
fprintf(stderr, "Error: failed to extract has_texcoords\n");
return false;
}
if(has_texcoords) {
temp_texcoords.resize(num_vertices);
if(!model_loader.extract_list(&temp_texcoords[0], num_vertices)) {
fprintf(stderr, "Error: failed to extract texture coordinates\n");
return false;
}
}
unsigned int num_faces;
if(!model_loader.extract<unsigned int>(&num_faces)) {
fprintf(stderr, "Error: failed to extract num_faces\n");
return false;
}
indices.resize(num_faces);
if(!model_loader.extract_list(&indices[0], num_faces)) {
fprintf(stderr, "Error: failed to extract face indices\n");
return false;
}
unsigned int triangles_offset = triangles.size();
triangles.resize(triangles.size() + indices.size());
const Vertex3D *temp_vertices_begin = &temp_vertices[0].p1;
unsigned int max_vertex_index = (unsigned int)(temp_vertices.size() - 1) * 3;
for(unsigned int i = 0; i < indices.size(); ++i) {
triangles[triangles_offset + i].p1 = temp_vertices_begin[std::min(indices[i].index[0], max_vertex_index)];
triangles[triangles_offset + i].p2 = temp_vertices_begin[std::min(indices[i].index[1], max_vertex_index)];
triangles[triangles_offset + i].p3 = temp_vertices_begin[std::min(indices[i].index[2], max_vertex_index)];
}
unsigned int texcoords_offset = texture_coords.size();
texture_coords.resize(texture_coords.size() + indices.size() * 3);
if(has_texcoords) {
unsigned int max_texcoord_index = (unsigned int)temp_texcoords.size() - 1;
for(unsigned int i = 0; i < indices.size(); ++i) {
texture_coords[texcoords_offset + 0] = temp_texcoords[std::min(indices[i].index[0], max_texcoord_index)];
texture_coords[texcoords_offset + 1] = temp_texcoords[std::min(indices[i].index[1], max_texcoord_index)];
texture_coords[texcoords_offset + 2] = temp_texcoords[std::min(indices[i].index[2], max_texcoord_index)];
texcoords_offset += 3;
}
} else {
for(unsigned int i = 0; i < indices.size(); ++i) {
// TODO: is this needed even with the resize above? or use memset?
texture_coords[texcoords_offset + i + 0] = { 0.0f, 0.0f };
texture_coords[texcoords_offset + i + 1] = { 0.0f, 0.0f };
texture_coords[texcoords_offset + i + 2] = { 0.0f, 0.0f };
}
}
unsigned int has_materials;
if(!model_loader.extract<unsigned int>(&has_materials) || has_materials > 1) {
fprintf(stderr, "Error: failed to extract has_materials\n");
return false;
}
if(has_materials) {
for(unsigned int i = 0; i < 3; ++i) {
unsigned int num_textures;
if(!model_loader.extract<unsigned int>(&num_textures)) {
fprintf(stderr, "Error: failed to extract num_textures\n");
return false;
}
for(unsigned int j = 0; j < num_textures; ++j) {
std::string texture_name = model_loader.extract_null_terminated_string();
if(texture_name.empty())
continue;
fprintf(stderr, "texture name: %s\n", texture_name.c_str());
std::string texture_path = dir_path + "/" + texture_name;
//assert(!*image); // TODO: Support multiple images
if(*image)
continue;
Result<Image*> image_result = Image::loadFromFile(texture_path.c_str());
if(!image_result) {
fprintf(stderr, "Warning: %s\n", image_result.getErrorMsg().c_str());
continue;
}
*image = image_result.unwrap();
}
}
}
}
return true;
}
// TODO: Instead of reading all file data to a buffer and then copying it, maybe read from file
// directly into data structures?
bool ModelLoader::load_from_file(const char *filepath, std::vector<Triangle3D> &triangles, std::vector<vec2f> &texture_coords, Image **image) {
triangles.clear();
texture_coords.clear();
*image = nullptr;
bool result = true;
size_t file_size;
char *file_data = file_get_content(filepath, &file_size);
if(!file_data)
return false;
std::string dir_path = filepath;
dirname(&dir_path[0]);
const int dir_path_size = strlen(dir_path.c_str());
dir_path.resize(dir_path_size);
ModelLoaderInternal model_loader(file_data, file_size);
unsigned int magic_number;
unsigned int version = 0;
if(!model_loader.extract<unsigned int>(&magic_number) || magic_number != 0x036144AF) {
fprintf(stderr, "Error: file %s is not an .a3d file (magic number not found)\n", filepath);
result = false;
goto cleanup;
}
if(model_loader.extract<unsigned int>(&version) && version == 1) {
result = model_loader_version_1(model_loader, triangles, texture_coords, image, dir_path);
} else {
fprintf(stderr, "Error: version not supported: %u\n", version);
result = false;
}
cleanup:
free(file_data);
return result;
}
}
|
