1 | // Copyright 2011 Google Inc. All Rights Reserved.
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2 | //
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3 | // Licensed under the Apache License, Version 2.0 (the "License"); you
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4 | // may not use this file except in compliance with the License. You
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5 | // may obtain a copy of the License at
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6 | //
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7 | // http://www.apache.org/licenses/LICENSE-2.0
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8 | //
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9 | // Unless required by applicable law or agreed to in writing, software
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10 | // distributed under the License is distributed on an "AS IS" BASIS,
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11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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12 | // implied. See the License for the specific language governing
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13 | // permissions and limitations under the License.
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14 |
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15 | #ifndef WEBGL_LOADER_MESH_H_
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16 | #define WEBGL_LOADER_MESH_H_
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17 |
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18 | #include <float.h>
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19 | #include <limits.h>
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20 | #include <math.h>
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21 | #include <stdio.h>
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22 | #include <stdlib.h>
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23 |
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24 | #include <map>
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25 | #include <string>
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26 | #include <utility>
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27 | #include <vector>
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28 |
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29 | #include "base.h"
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30 | #include "bounds.h"
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31 | #include "stream.h"
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32 | #include "utf8.h"
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33 |
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34 | // A short list of floats, useful for parsing a single vector
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35 | // attribute.
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36 | class ShortFloatList {
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37 | public:
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38 | // MeshLab can create position attributes with
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39 | // color coordinates like: v x y z r g b
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40 | static const size_t kMaxNumFloats = 6;
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41 | ShortFloatList()
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42 | : size_(0)
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43 | {
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44 | clear();
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45 | }
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46 |
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47 | void clear() {
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48 | for (size_t i = 0; i < kMaxNumFloats; ++i) {
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49 | a_[i] = 0.f;
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50 | }
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51 | }
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52 |
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53 | // Parse up to kMaxNumFloats from C string.
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54 | // TODO: this should instead return endptr, since size
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55 | // is recoverable.
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56 | size_t ParseLine(const char* line) {
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57 | for (size_ = 0; size_ != kMaxNumFloats; ++size_) {
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58 | char* endptr = NULL;
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59 | a_[size_] = strtof(line, &endptr);
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60 | if (endptr == NULL || line == endptr) break;
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61 | line = endptr;
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62 | }
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63 | return size_;
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64 | }
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65 |
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66 | float operator[](size_t idx) const {
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67 | return a_[idx];
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68 | }
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69 |
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70 | void AppendTo(AttribList* attribs) const {
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71 | AppendNTo(attribs, size_);
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72 | }
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73 |
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74 | void AppendNTo(AttribList* attribs, const size_t sz) const {
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75 | attribs->insert(attribs->end(), a_, a_ + sz);
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76 | }
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77 |
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78 | bool empty() const { return size_ == 0; }
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79 |
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80 | size_t size() const { return size_; }
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81 | private:
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82 | float a_[kMaxNumFloats];
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83 | size_t size_;
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84 | };
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85 |
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86 | class IndexFlattener {
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87 | public:
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88 | explicit IndexFlattener(size_t num_positions)
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89 | : count_(0),
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90 | table_(num_positions) {
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91 | }
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92 |
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93 | int count() const { return count_; }
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94 |
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95 | void reserve(size_t size) {
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96 | table_.reserve(size);
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97 | }
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98 |
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99 | // Returns a pair of: < flattened index, newly inserted >.
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100 | std::pair<int, bool> GetFlattenedIndex(int position_index,
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101 | int texcoord_index,
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102 | int normal_index) {
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103 | if (position_index >= static_cast<int>(table_.size())) {
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104 | table_.resize(position_index + 1);
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105 | }
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106 | // First, optimistically look up position_index in the table.
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107 | IndexType& index = table_[position_index];
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108 | if (index.position_or_flat == kIndexUnknown) {
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109 | // This is the first time we've seen this position in the table,
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110 | // so fill it. Since the table is indexed by position, we can
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111 | // use the position_or_flat_index field to store the flat index.
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112 | const int flat_index = count_++;
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113 | index.position_or_flat = flat_index;
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114 | index.texcoord = texcoord_index;
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115 | index.normal = normal_index;
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116 | return std::make_pair(flat_index, true);
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117 | } else if (index.position_or_flat == kIndexNotInTable) {
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118 | // There are multiple flattened indices at this position index,
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119 | // so resort to the map.
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120 | return GetFlattenedIndexFromMap(position_index,
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121 | texcoord_index,
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122 | normal_index);
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123 | } else if (index.texcoord == texcoord_index &&
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124 | index.normal == normal_index) {
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125 | // The other indices match, so we can use the value cached in
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126 | // the table.
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127 | return std::make_pair(index.position_or_flat, false);
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128 | }
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129 | // The other indices don't match, so we mark this table entry,
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130 | // and insert both the old and new indices into the map.
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131 | const IndexType old_index(position_index, index.texcoord, index.normal);
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132 | map_.insert(std::make_pair(old_index, index.position_or_flat));
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133 | index.position_or_flat = kIndexNotInTable;
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134 | const IndexType new_index(position_index, texcoord_index, normal_index);
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135 | const int flat_index = count_++;
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136 | map_.insert(std::make_pair(new_index, flat_index));
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137 | return std::make_pair(flat_index, true);
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138 | }
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139 | private:
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140 | std::pair<int, bool> GetFlattenedIndexFromMap(int position_index,
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141 | int texcoord_index,
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142 | int normal_index) {
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143 | IndexType index(position_index, texcoord_index, normal_index);
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144 | MapType::iterator iter = map_.lower_bound(index);
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145 | if (iter == map_.end() || iter->first != index) {
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146 | const int flat_index = count_++;
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147 | map_.insert(iter, std::make_pair(index, flat_index));
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148 | return std::make_pair(flat_index, true);
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149 | } else {
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150 | return std::make_pair(iter->second, false);
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151 | }
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152 | }
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153 |
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154 | static const int kIndexUnknown = -1;
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155 | static const int kIndexNotInTable = -2;
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156 |
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157 | struct IndexType {
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158 | IndexType()
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159 | : position_or_flat(kIndexUnknown),
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160 | texcoord(kIndexUnknown),
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161 | normal(kIndexUnknown)
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162 | { }
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163 |
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164 | IndexType(int position_index, int texcoord_index, int normal_index)
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165 | : position_or_flat(position_index),
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166 | texcoord(texcoord_index),
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167 | normal(normal_index)
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168 | { }
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169 |
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170 | // I'm being tricky/lazy here. The table_ stores the flattened
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171 | // index in the first field, since it is indexed by position. The
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172 | // map_ stores position and uses this struct as a key to lookup the
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173 | // flattened index.
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174 | int position_or_flat;
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175 | int texcoord;
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176 | int normal;
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177 |
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178 | // An ordering for std::map.
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179 | bool operator<(const IndexType& that) const {
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180 | if (position_or_flat == that.position_or_flat) {
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181 | if (texcoord == that.texcoord) {
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182 | return normal < that.normal;
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183 | } else {
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184 | return texcoord < that.texcoord;
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185 | }
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186 | } else {
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187 | return position_or_flat < that.position_or_flat;
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188 | }
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189 | }
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190 |
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191 | bool operator==(const IndexType& that) const {
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192 | return position_or_flat == that.position_or_flat &&
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193 | texcoord == that.texcoord && normal == that.normal;
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194 | }
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195 |
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196 | bool operator!=(const IndexType& that) const {
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197 | return !operator==(that);
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198 | }
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199 | };
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200 | typedef std::map<IndexType, int> MapType;
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201 |
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202 | int count_;
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203 | std::vector<IndexType> table_;
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204 | MapType map_;
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205 | };
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206 |
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207 | static inline size_t positionDim() { return 3; }
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208 | static inline size_t texcoordDim() { return 2; }
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209 | static inline size_t normalDim() { return 3; }
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210 |
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211 | // TODO(wonchun): Make a c'tor to properly initialize.
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212 | struct GroupStart {
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213 | size_t offset; // offset into draw_mesh_.indices.
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214 | unsigned int group_line;
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215 | int min_index, max_index; // range into attribs.
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216 | webgl_loader::Bounds bounds;
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217 | };
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218 |
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219 | class DrawBatch {
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220 | public:
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221 | DrawBatch()
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222 | : flattener_(0),
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223 | current_group_line_(0xFFFFFFFF) {
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224 | }
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225 |
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226 | const std::vector<GroupStart>& group_starts() const {
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227 | return group_starts_;
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228 | }
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229 |
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230 | void Init(AttribList* positions, AttribList* texcoords, AttribList* normals) {
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231 | positions_ = positions;
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232 | texcoords_ = texcoords;
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233 | normals_ = normals;
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234 | flattener_.reserve(1024);
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235 | }
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236 |
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237 | void AddTriangle(unsigned int group_line, int* indices) {
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238 | if (group_line != current_group_line_) {
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239 | current_group_line_ = group_line;
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240 | GroupStart group_start;
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241 | group_start.offset = draw_mesh_.indices.size();
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242 | group_start.group_line = group_line;
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243 | group_start.min_index = INT_MAX;
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244 | group_start.max_index = INT_MIN;
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245 | group_start.bounds.Clear();
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246 | group_starts_.push_back(group_start);
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247 | }
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248 | GroupStart& group = group_starts_.back();
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249 | for (size_t i = 0; i < 9; i += 3) {
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250 | // .OBJ files use 1-based indexing.
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251 | const int position_index = indices[i + 0] - 1;
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252 | const int texcoord_index = indices[i + 1] - 1;
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253 | const int normal_index = indices[i + 2] - 1;
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254 | const std::pair<int, bool> flattened = flattener_.GetFlattenedIndex(
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255 | position_index, texcoord_index, normal_index);
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256 | const int flat_index = flattened.first;
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257 | CHECK(flat_index >= 0);
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258 | draw_mesh_.indices.push_back(flat_index);
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259 | if (flattened.second) {
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260 | // This is a new index. Keep track of index ranges and vertex
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261 | // bounds.
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262 | if (flat_index > group.max_index) {
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263 | group.max_index = flat_index;
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264 | }
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265 | if (flat_index < group.min_index) {
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266 | group.min_index = flat_index;
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267 | }
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268 | const size_t new_loc = draw_mesh_.attribs.size();
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269 | CHECK(8*size_t(flat_index) == new_loc);
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270 | for (size_t i = 0; i < positionDim(); ++i) {
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271 | draw_mesh_.attribs.push_back(
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272 | positions_->at(positionDim() * position_index + i));
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273 | }
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274 | if (texcoord_index == -1) {
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275 | for (size_t i = 0; i < texcoordDim(); ++i) {
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276 | draw_mesh_.attribs.push_back(0);
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277 | }
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278 | } else {
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279 | for (size_t i = 0; i < texcoordDim(); ++i) {
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280 | draw_mesh_.attribs.push_back(
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281 | texcoords_->at(texcoordDim() * texcoord_index + i));
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282 | }
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283 | }
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284 | if (normal_index == -1) {
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285 | for (size_t i = 0; i < normalDim(); ++i) {
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286 | draw_mesh_.attribs.push_back(0);
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287 | }
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288 | } else {
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289 | for (size_t i = 0; i < normalDim(); ++i) {
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290 | draw_mesh_.attribs.push_back(
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291 | normals_->at(normalDim() * normal_index + i));
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292 | }
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293 | }
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294 | // TODO: is the covariance body useful for anything?
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295 | group.bounds.EncloseAttrib(&draw_mesh_.attribs[new_loc]);
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296 | }
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297 | }
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298 | }
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299 |
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300 | const DrawMesh& draw_mesh() const {
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301 | return draw_mesh_;
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302 | }
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303 | private:
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304 | AttribList* positions_, *texcoords_, *normals_;
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305 | DrawMesh draw_mesh_;
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306 | IndexFlattener flattener_;
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307 | unsigned int current_group_line_;
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308 | std::vector<GroupStart> group_starts_;
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309 | };
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310 |
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311 | struct Material {
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312 | std::string name;
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313 | float Kd[3];
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314 | std::string map_Kd;
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315 |
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316 | void DumpJson(FILE* out = stdout) const {
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317 | fprintf(out, " \"%s\": { ", name.c_str());
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318 | if (map_Kd.empty()) {
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319 | fprintf(out, "\"Kd\": [%hu, %hu, %hu] }",
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320 | Quantize(Kd[0], 0, 1, 255),
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321 | Quantize(Kd[1], 0, 1, 255),
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322 | Quantize(Kd[2], 0, 1, 255));
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323 | } else {
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324 | fprintf(out, "\"map_Kd\": \"%s\" }", map_Kd.c_str());
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325 | }
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326 | }
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327 | };
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328 |
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329 | typedef std::vector<Material> MaterialList;
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330 |
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331 | class WavefrontMtlFile {
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332 | public:
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333 | explicit WavefrontMtlFile(FILE* fp) {
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334 | ParseFile(fp);
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335 | }
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336 |
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337 | const MaterialList& materials() const {
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338 | return materials_;
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339 | }
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340 |
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341 | private:
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342 | // TODO: factor this parsing stuff out.
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343 | void ParseFile(FILE* fp) {
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344 | // TODO: don't use a fixed-size buffer.
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345 | const size_t kLineBufferSize = 256;
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346 | char buffer[kLineBufferSize];
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347 | unsigned int line_num = 1;
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348 | while (fgets(buffer, kLineBufferSize, fp) != NULL) {
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349 | char* stripped = StripLeadingWhitespace(buffer);
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350 | TerminateAtNewlineOrComment(stripped);
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351 | ParseLine(stripped, line_num++);
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352 | }
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353 | }
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354 |
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355 | void ParseLine(const char* line, unsigned int line_num) {
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356 | switch (*line) {
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357 | case 'K':
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358 | ParseColor(line + 1, line_num);
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359 | break;
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360 | case 'm':
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361 | if (0 == strncmp(line + 1, "ap_Kd", 5)) {
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362 | ParseMapKd(line + 6, line_num);
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363 | }
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364 | break;
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365 | case 'n':
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366 | if (0 == strncmp(line + 1, "ewmtl", 5)) {
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367 | ParseNewmtl(line + 6, line_num);
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368 | }
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369 | default:
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370 | break;
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371 | }
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372 | }
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373 |
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374 | void ParseColor(const char* line, unsigned int line_num) {
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375 | switch (*line) {
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376 | case 'd': {
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377 | ShortFloatList floats;
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378 | floats.ParseLine(line + 1);
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379 | float* Kd = current_->Kd;
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380 | Kd[0] = floats[0];
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381 | Kd[1] = floats[1];
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382 | Kd[2] = floats[2];
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383 | break;
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384 | }
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385 | default:
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386 | break;
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387 | }
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388 | }
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389 |
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390 | void ParseMapKd(const char* line, unsigned int line_num) {
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391 | current_->map_Kd = StripLeadingWhitespace(line);
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392 | }
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393 |
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394 | void ParseNewmtl(const char* line, unsigned int line_num) {
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395 | materials_.push_back(Material());
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396 | current_ = &materials_.back();
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397 | ToLower(StripLeadingWhitespace(line), ¤t_->name);
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398 | }
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399 |
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400 | Material* current_;
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401 | MaterialList materials_;
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402 | };
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403 |
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404 | typedef std::map<std::string, DrawBatch> MaterialBatches;
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405 |
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406 | // TODO: consider splitting this into a low-level parser and a high-level
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407 | // object.
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408 | class WavefrontObjFile {
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409 | public:
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410 | explicit WavefrontObjFile(FILE* fp) {
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411 | current_batch_ = &material_batches_[""];
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412 | current_batch_->Init(&positions_, &texcoords_, &normals_);
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413 | current_group_line_ = 0;
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414 | line_to_groups_.insert(std::make_pair(0, "default"));
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415 | ParseFile(fp);
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416 | }
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417 |
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418 | const MaterialList& materials() const {
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419 | return materials_;
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420 | }
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421 |
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422 | const MaterialBatches& material_batches() const {
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423 | return material_batches_;
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424 | }
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425 |
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426 | const std::string& LineToGroup(unsigned int line) const {
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427 | typedef LineToGroups::const_iterator Iterator;
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428 | typedef std::pair<Iterator, Iterator> EqualRange;
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429 | EqualRange equal_range = line_to_groups_.equal_range(line);
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430 | const std::string* best_group = NULL;
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431 | int best_count = 0;
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432 | for (Iterator iter = equal_range.first; iter != equal_range.second;
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433 | ++iter) {
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434 | const std::string& group = iter->second;
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435 | const int count = group_counts_.find(group)->second;
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436 | if (!best_group || (count < best_count)) {
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437 | best_group = &group;
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438 | best_count = count;
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439 | }
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440 | }
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441 | if (!best_group) {
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442 | ErrorLine("no suitable group found", line);
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443 | }
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444 | return *best_group;
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445 | }
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446 |
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447 | void DumpDebug() const {
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448 | printf("positions size: " PRIuS "\n"
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449 | "texcoords size: " PRIuS "\n"
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450 | "normals size: " PRIuS "\n",
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451 | positions_.size(), texcoords_.size(), normals_.size());
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452 | }
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453 | private:
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454 | WavefrontObjFile() { } // For testing.
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455 |
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456 | void ParseFile(FILE* fp) {
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457 | // TODO: don't use a fixed-size buffer.
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458 | const size_t kLineBufferSize = 256;
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459 | char buffer[kLineBufferSize] = { 0 };
|
---|
460 | unsigned int line_num = 1;
|
---|
461 | while (fgets(buffer, kLineBufferSize, fp) != NULL) {
|
---|
462 | char* stripped = StripLeadingWhitespace(buffer);
|
---|
463 | TerminateAtNewlineOrComment(stripped);
|
---|
464 | ParseLine(stripped, line_num++);
|
---|
465 | }
|
---|
466 | }
|
---|
467 |
|
---|
468 | void ParseLine(const char* line, unsigned int line_num) {
|
---|
469 | switch (*line) {
|
---|
470 | case 'v':
|
---|
471 | ParseAttrib(line + 1, line_num);
|
---|
472 | break;
|
---|
473 | case 'f':
|
---|
474 | ParseFace(line + 1, line_num);
|
---|
475 | break;
|
---|
476 | case 'g':
|
---|
477 | if (isspace(line[1])) {
|
---|
478 | ParseGroup(line + 2, line_num);
|
---|
479 | } else {
|
---|
480 | goto unknown;
|
---|
481 | }
|
---|
482 | break;
|
---|
483 | case '\0':
|
---|
484 | case '#':
|
---|
485 | break; // Do nothing for comments or blank lines.
|
---|
486 | case 'p':
|
---|
487 | WarnLine("point unsupported", line_num);
|
---|
488 | break;
|
---|
489 | case 'l':
|
---|
490 | WarnLine("line unsupported", line_num);
|
---|
491 | break;
|
---|
492 | case 'u':
|
---|
493 | if (0 == strncmp(line + 1, "semtl", 5)) {
|
---|
494 | ParseUsemtl(line + 6, line_num);
|
---|
495 | } else {
|
---|
496 | goto unknown;
|
---|
497 | }
|
---|
498 | break;
|
---|
499 | case 'm':
|
---|
500 | if (0 == strncmp(line + 1, "tllib", 5)) {
|
---|
501 | ParseMtllib(line + 6, line_num);
|
---|
502 | } else {
|
---|
503 | goto unknown;
|
---|
504 | }
|
---|
505 | break;
|
---|
506 | case 's':
|
---|
507 | ParseSmoothingGroup(line + 1, line_num);
|
---|
508 | break;
|
---|
509 | unknown:
|
---|
510 | default:
|
---|
511 | WarnLine("unknown keyword", line_num);
|
---|
512 | break;
|
---|
513 | }
|
---|
514 | }
|
---|
515 |
|
---|
516 | void ParseAttrib(const char* line, unsigned int line_num) {
|
---|
517 | ShortFloatList floats;
|
---|
518 | floats.ParseLine(line + 1);
|
---|
519 | if (isspace(*line)) {
|
---|
520 | ParsePosition(floats, line_num);
|
---|
521 | } else if (*line == 't') {
|
---|
522 | ParseTexCoord(floats, line_num);
|
---|
523 | } else if (*line == 'n') {
|
---|
524 | ParseNormal(floats, line_num);
|
---|
525 | } else {
|
---|
526 | WarnLine("unknown attribute format", line_num);
|
---|
527 | }
|
---|
528 | }
|
---|
529 |
|
---|
530 | void ParsePosition(const ShortFloatList& floats, unsigned int line_num) {
|
---|
531 | if (floats.size() != positionDim() &&
|
---|
532 | floats.size() != 6) { // ignore r g b for now.
|
---|
533 | ErrorLine("bad position", line_num);
|
---|
534 | }
|
---|
535 | floats.AppendNTo(&positions_, positionDim());
|
---|
536 | }
|
---|
537 |
|
---|
538 | void ParseTexCoord(const ShortFloatList& floats, unsigned int line_num) {
|
---|
539 | if ((floats.size() < 1) || (floats.size() > 3)) {
|
---|
540 | // TODO: correctly handle 3-D texcoords intead of just
|
---|
541 | // truncating.
|
---|
542 | ErrorLine("bad texcoord", line_num);
|
---|
543 | }
|
---|
544 | floats.AppendNTo(&texcoords_, texcoordDim());
|
---|
545 | }
|
---|
546 |
|
---|
547 | void ParseNormal(const ShortFloatList& floats, unsigned int line_num) {
|
---|
548 | if (floats.size() != normalDim()) {
|
---|
549 | ErrorLine("bad normal", line_num);
|
---|
550 | }
|
---|
551 | // Normalize to avoid out-of-bounds quantization. This should be
|
---|
552 | // optional, in case someone wants to be using the normal magnitude as
|
---|
553 | // something meaningful.
|
---|
554 | const float x = floats[0];
|
---|
555 | const float y = floats[1];
|
---|
556 | const float z = floats[2];
|
---|
557 | const float scale = 1.0/sqrt(x*x + y*y + z*z);
|
---|
558 | if (isfinite(scale)) {
|
---|
559 | normals_.push_back(scale * x);
|
---|
560 | normals_.push_back(scale * y);
|
---|
561 | normals_.push_back(scale * z);
|
---|
562 | } else {
|
---|
563 | normals_.push_back(0);
|
---|
564 | normals_.push_back(0);
|
---|
565 | normals_.push_back(0);
|
---|
566 | }
|
---|
567 | }
|
---|
568 |
|
---|
569 | // Parses faces and converts to triangle fans. This is not a
|
---|
570 | // particularly good tesselation in general case, but it is really
|
---|
571 | // simple, and is perfectly fine for triangles and quads.
|
---|
572 | void ParseFace(const char* line, unsigned int line_num) {
|
---|
573 | // Also handle face outlines as faces.
|
---|
574 | if (*line == 'o') ++line;
|
---|
575 |
|
---|
576 | // TODO: instead of storing these indices as-is, it might make
|
---|
577 | // sense to flatten them right away. This can reduce memory
|
---|
578 | // consumption and improve access locality, especially since .OBJ
|
---|
579 | // face indices are so needlessly large.
|
---|
580 | int indices[9] = { 0 };
|
---|
581 | // The first index acts as the pivot for the triangle fan.
|
---|
582 | line = ParseIndices(line, line_num, indices + 0, indices + 1, indices + 2);
|
---|
583 | if (line == NULL) {
|
---|
584 | ErrorLine("bad first index", line_num);
|
---|
585 | }
|
---|
586 | line = ParseIndices(line, line_num, indices + 3, indices + 4, indices + 5);
|
---|
587 | if (line == NULL) {
|
---|
588 | ErrorLine("bad second index", line_num);
|
---|
589 | }
|
---|
590 | // After the first two indices, each index introduces a new
|
---|
591 | // triangle to the fan.
|
---|
592 | while ((line = ParseIndices(line, line_num,
|
---|
593 | indices + 6, indices + 7, indices + 8))) {
|
---|
594 | current_batch_->AddTriangle(current_group_line_, indices);
|
---|
595 | // The most recent vertex is reused for the next triangle.
|
---|
596 | indices[3] = indices[6];
|
---|
597 | indices[4] = indices[7];
|
---|
598 | indices[5] = indices[8];
|
---|
599 | indices[6] = indices[7] = indices[8] = 0;
|
---|
600 | }
|
---|
601 | }
|
---|
602 |
|
---|
603 | // Parse a single group of indices, separated by slashes ('/').
|
---|
604 | // TODO: convert negative indices (that is, relative to the end of
|
---|
605 | // the current vertex positions) to more conventional positive
|
---|
606 | // indices.
|
---|
607 | const char* ParseIndices(const char* line, unsigned int line_num,
|
---|
608 | int* position_index, int* texcoord_index,
|
---|
609 | int* normal_index) {
|
---|
610 | const char* endptr = NULL;
|
---|
611 | *position_index = strtoint(line, &endptr);
|
---|
612 | if (*position_index == 0) {
|
---|
613 | return NULL;
|
---|
614 | }
|
---|
615 | if (endptr != NULL && *endptr == '/') {
|
---|
616 | *texcoord_index = strtoint(endptr + 1, &endptr);
|
---|
617 | } else {
|
---|
618 | *texcoord_index = *normal_index = 0;
|
---|
619 | }
|
---|
620 | if (endptr != NULL && *endptr == '/') {
|
---|
621 | *normal_index = strtoint(endptr + 1, &endptr);
|
---|
622 | } else {
|
---|
623 | *normal_index = 0;
|
---|
624 | }
|
---|
625 | return endptr;
|
---|
626 | }
|
---|
627 |
|
---|
628 | // .OBJ files can specify multiple groups for a set of faces. This
|
---|
629 | // implementation finds the "most unique" group for a set of faces
|
---|
630 | // and uses that for the batch. In the first pass, we use the line
|
---|
631 | // number of the "g" command to tag the faces. Afterwards, after we
|
---|
632 | // collect group populations, we can go back and give them real
|
---|
633 | // names.
|
---|
634 | void ParseGroup(const char* line, unsigned int line_num) {
|
---|
635 | std::string token;
|
---|
636 | while ((line = ConsumeFirstToken(line, &token))) {
|
---|
637 | ToLowerInplace(&token);
|
---|
638 | group_counts_[token]++;
|
---|
639 | line_to_groups_.insert(std::make_pair(line_num, token));
|
---|
640 | }
|
---|
641 | current_group_line_ = line_num;
|
---|
642 | }
|
---|
643 |
|
---|
644 | void ParseSmoothingGroup(const char* line, unsigned int line_num) {
|
---|
645 | static bool once = true;
|
---|
646 | if (once) {
|
---|
647 | WarnLine("s ignored", line_num);
|
---|
648 | once = false;
|
---|
649 | }
|
---|
650 | }
|
---|
651 |
|
---|
652 | void ParseMtllib(const char* line, unsigned int line_num) {
|
---|
653 | FILE* fp = fopen(StripLeadingWhitespace(line), "r");
|
---|
654 | if (!fp) {
|
---|
655 | WarnLine("mtllib not found", line_num);
|
---|
656 | return;
|
---|
657 | }
|
---|
658 | WavefrontMtlFile mtlfile(fp);
|
---|
659 | fclose(fp);
|
---|
660 | materials_ = mtlfile.materials();
|
---|
661 | for (size_t i = 0; i < materials_.size(); ++i) {
|
---|
662 | DrawBatch& draw_batch = material_batches_[materials_[i].name];
|
---|
663 | draw_batch.Init(&positions_, &texcoords_, &normals_);
|
---|
664 | }
|
---|
665 | }
|
---|
666 |
|
---|
667 | void ParseUsemtl(const char* line, unsigned int line_num) {
|
---|
668 | std::string usemtl;
|
---|
669 | ToLower(StripLeadingWhitespace(line), &usemtl);
|
---|
670 | MaterialBatches::iterator iter = material_batches_.find(usemtl);
|
---|
671 | if (iter == material_batches_.end()) {
|
---|
672 | ErrorLine("material not found", line_num);
|
---|
673 | }
|
---|
674 | current_batch_ = &iter->second;
|
---|
675 | }
|
---|
676 |
|
---|
677 | void WarnLine(const char* why, unsigned int line_num) const {
|
---|
678 | fprintf(stderr, "WARNING: %s at line %u\n", why, line_num);
|
---|
679 | }
|
---|
680 |
|
---|
681 | void ErrorLine(const char* why, unsigned int line_num) const {
|
---|
682 | fprintf(stderr, "ERROR: %s at line %u\n", why, line_num);
|
---|
683 | exit(-1);
|
---|
684 | }
|
---|
685 |
|
---|
686 | AttribList positions_;
|
---|
687 | AttribList texcoords_;
|
---|
688 | AttribList normals_;
|
---|
689 | MaterialList materials_;
|
---|
690 |
|
---|
691 | // Currently, batch by texture (i.e. map_Kd).
|
---|
692 | MaterialBatches material_batches_;
|
---|
693 | DrawBatch* current_batch_;
|
---|
694 |
|
---|
695 | typedef std::multimap<unsigned int, std::string> LineToGroups;
|
---|
696 | LineToGroups line_to_groups_;
|
---|
697 | std::map<std::string, int> group_counts_;
|
---|
698 | unsigned int current_group_line_;
|
---|
699 | };
|
---|
700 |
|
---|
701 | #endif // WEBGL_LOADER_MESH_H_
|
---|