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-rw-r--r--obj_loader.cpp428
1 files changed, 0 insertions, 428 deletions
diff --git a/obj_loader.cpp b/obj_loader.cpp
deleted file mode 100644
index 7611a2c..0000000
--- a/obj_loader.cpp
+++ /dev/null
@@ -1,428 +0,0 @@
-#include "obj_loader.h"
-#include <algorithm>
-#include <fstream>
-#include <map>
-#include <memory>
-#include <stdexcept>
-#include <utility>
-
-static bool CompareOBJIndexPtr(const OBJIndex * a, const OBJIndex * b);
-static inline unsigned int FindNextChar(unsigned int start, const char * str, unsigned int length, char token);
-static inline unsigned int ParseOBJIndexValue(const std::string & token, unsigned int start, unsigned int end);
-static inline float ParseOBJFloatValue(const std::string & token, unsigned int start, unsigned int end);
-static inline std::vector<std::string> SplitString(const std::string & s, char delim);
-
-OBJModel::OBJModel(const std::string & fileName)
-{
- hasUVs = false;
- hasNormals = false;
- std::ifstream file;
- file.open(fileName.c_str());
-
- std::string line;
- if (file.is_open()) {
- while (file.good()) {
- getline(file, line);
-
- unsigned int lineLength = line.length();
-
- if (lineLength < 2) {
- continue;
- }
-
- const char * lineCStr = line.c_str();
-
- switch (lineCStr[0]) {
- case 'v':
- switch (lineCStr[1]) {
- case 't':
- this->uvs.push_back(ParseOBJVec2(line));
- break;
- case 'n':
- this->normals.push_back(ParseOBJVec3(line));
- break;
- case ' ':
- case '\t':
- this->vertices.push_back(ParseOBJVec3(line));
- }
- break;
- case 'f':
- CreateOBJFace(line);
- break;
- default:
- break;
- };
- }
- }
- else {
- throw std::runtime_error {"Unable to load mesh: " + fileName};
- }
-}
-
-void
-IndexedModel::CalcNormals()
-{
- for (unsigned int i = 0; i < indices.size(); i += 3) {
- int i0 = indices[i];
- int i1 = indices[i + 1];
- int i2 = indices[i + 2];
-
- glm::vec3 v1 = positions[i1] - positions[i0];
- glm::vec3 v2 = positions[i2] - positions[i0];
-
- glm::vec3 normal = glm::normalize(glm::cross(v1, v2));
-
- normals[i0] += normal;
- normals[i1] += normal;
- normals[i2] += normal;
- }
-
- for (unsigned int i = 0; i < positions.size(); i++) {
- normals[i] = glm::normalize(normals[i]);
- }
-}
-
-IndexedModel
-OBJModel::ToIndexedModel()
-{
- IndexedModel result;
- IndexedModel normalModel;
-
- unsigned int numIndices = OBJIndices.size();
-
- std::vector<OBJIndex *> indexLookup;
-
- for (unsigned int i = 0; i < numIndices; i++) {
- indexLookup.push_back(&OBJIndices[i]);
- }
-
- std::sort(indexLookup.begin(), indexLookup.end(), CompareOBJIndexPtr);
-
- std::map<OBJIndex, unsigned int> normalModelIndexMap;
- std::map<unsigned int, unsigned int> indexMap;
-
- for (unsigned int i = 0; i < numIndices; i++) {
- OBJIndex * currentIndex = &OBJIndices[i];
-
- glm::vec3 currentPosition = vertices[currentIndex->vertexIndex];
- glm::vec2 currentTexCoord;
- glm::vec3 currentNormal;
-
- if (hasUVs) {
- currentTexCoord = uvs[currentIndex->uvIndex];
- }
- else {
- currentTexCoord = glm::vec2(0, 0);
- }
-
- if (hasNormals) {
- currentNormal = normals[currentIndex->normalIndex];
- }
- else {
- currentNormal = glm::vec3(0, 0, 0);
- }
-
- unsigned int normalModelIndex;
- unsigned int resultModelIndex;
-
- // Create model to properly generate normals on
- const auto it = normalModelIndexMap.find(*currentIndex);
- if (it == normalModelIndexMap.end()) {
- normalModelIndex = normalModel.positions.size();
-
- normalModelIndexMap.insert(std::pair<OBJIndex, unsigned int>(*currentIndex, normalModelIndex));
- normalModel.positions.push_back(currentPosition);
- normalModel.texCoords.push_back(currentTexCoord);
- normalModel.normals.push_back(currentNormal);
- }
- else {
- normalModelIndex = it->second;
- }
-
- // Create model which properly separates texture coordinates
- unsigned int previousVertexLocation = FindLastVertexIndex(indexLookup, currentIndex, result);
-
- if (previousVertexLocation == (unsigned int)-1) {
- resultModelIndex = result.positions.size();
-
- result.positions.push_back(currentPosition);
- result.texCoords.push_back(currentTexCoord);
- result.normals.push_back(currentNormal);
- }
- else {
- resultModelIndex = previousVertexLocation;
- }
-
- normalModel.indices.push_back(normalModelIndex);
- result.indices.push_back(resultModelIndex);
- indexMap.insert(std::pair<unsigned int, unsigned int>(resultModelIndex, normalModelIndex));
- }
-
- if (!hasNormals) {
- normalModel.CalcNormals();
-
- for (unsigned int i = 0; i < result.positions.size(); i++) {
- result.normals[i] = normalModel.normals[indexMap[i]];
- }
- }
-
- return result;
-};
-
-unsigned int
-OBJModel::FindLastVertexIndex(
- const std::vector<OBJIndex *> & indexLookup, const OBJIndex * currentIndex, const IndexedModel & result)
-{
- unsigned int start = 0;
- unsigned int end = indexLookup.size();
- unsigned int current = (end - start) / 2 + start;
- unsigned int previous = start;
-
- while (current != previous) {
- OBJIndex * testIndex = indexLookup[current];
-
- if (testIndex->vertexIndex == currentIndex->vertexIndex) {
- unsigned int countStart = current;
-
- for (unsigned int i = 0; i < current; i++) {
- OBJIndex * possibleIndex = indexLookup[current - i];
-
- if (possibleIndex == currentIndex) {
- continue;
- }
-
- if (possibleIndex->vertexIndex != currentIndex->vertexIndex) {
- break;
- }
-
- countStart--;
- }
-
- for (unsigned int i = countStart; i < indexLookup.size() - countStart; i++) {
- OBJIndex * possibleIndex = indexLookup[current + i];
-
- if (possibleIndex == currentIndex) {
- continue;
- }
-
- if (possibleIndex->vertexIndex != currentIndex->vertexIndex) {
- break;
- }
- else if ((!hasUVs || possibleIndex->uvIndex == currentIndex->uvIndex)
- && (!hasNormals || possibleIndex->normalIndex == currentIndex->normalIndex)) {
- glm::vec3 currentPosition = vertices[currentIndex->vertexIndex];
- glm::vec2 currentTexCoord;
- glm::vec3 currentNormal;
-
- if (hasUVs) {
- currentTexCoord = uvs[currentIndex->uvIndex];
- }
- else {
- currentTexCoord = glm::vec2(0, 0);
- }
-
- if (hasNormals) {
- currentNormal = normals[currentIndex->normalIndex];
- }
- else {
- currentNormal = glm::vec3(0, 0, 0);
- }
-
- for (unsigned int j = 0; j < result.positions.size(); j++) {
- if (currentPosition == result.positions[j]
- && ((!hasUVs || currentTexCoord == result.texCoords[j])
- && (!hasNormals || currentNormal == result.normals[j]))) {
- return j;
- }
- }
- }
- }
-
- return -1;
- }
- else {
- if (testIndex->vertexIndex < currentIndex->vertexIndex) {
- start = current;
- }
- else {
- end = current;
- }
- }
-
- previous = current;
- current = (end - start) / 2 + start;
- }
-
- return -1;
-}
-
-void
-OBJModel::CreateOBJFace(const std::string & line)
-{
- std::vector<std::string> tokens = SplitString(line, ' ');
-
- this->OBJIndices.push_back(ParseOBJIndex(tokens[1], &this->hasUVs, &this->hasNormals));
- this->OBJIndices.push_back(ParseOBJIndex(tokens[2], &this->hasUVs, &this->hasNormals));
- this->OBJIndices.push_back(ParseOBJIndex(tokens[3], &this->hasUVs, &this->hasNormals));
-
- if ((int)tokens.size() > 4) {
- this->OBJIndices.push_back(ParseOBJIndex(tokens[1], &this->hasUVs, &this->hasNormals));
- this->OBJIndices.push_back(ParseOBJIndex(tokens[3], &this->hasUVs, &this->hasNormals));
- this->OBJIndices.push_back(ParseOBJIndex(tokens[4], &this->hasUVs, &this->hasNormals));
- }
-}
-
-OBJIndex
-OBJModel::ParseOBJIndex(const std::string & token, bool * hasUVs, bool * hasNormals)
-{
- unsigned int tokenLength = token.length();
- const char * tokenString = token.c_str();
-
- unsigned int vertIndexStart = 0;
- unsigned int vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, '/');
-
- OBJIndex result {
- .vertexIndex = ParseOBJIndexValue(token, vertIndexStart, vertIndexEnd),
- .uvIndex = 0,
- .normalIndex = 0,
- };
-
- if (vertIndexEnd >= tokenLength) {
- return result;
- }
-
- vertIndexStart = vertIndexEnd + 1;
- vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, '/');
-
- result.uvIndex = ParseOBJIndexValue(token, vertIndexStart, vertIndexEnd);
- *hasUVs = true;
-
- if (vertIndexEnd >= tokenLength) {
- return result;
- }
-
- vertIndexStart = vertIndexEnd + 1;
- vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, '/');
-
- result.normalIndex = ParseOBJIndexValue(token, vertIndexStart, vertIndexEnd);
- *hasNormals = true;
-
- return result;
-}
-
-glm::vec3
-OBJModel::ParseOBJVec3(const std::string & line)
-{
- unsigned int tokenLength = line.length();
- const char * tokenString = line.c_str();
-
- unsigned int vertIndexStart = 2;
-
- while (vertIndexStart < tokenLength) {
- if (tokenString[vertIndexStart] != ' ') {
- break;
- }
- vertIndexStart++;
- }
-
- unsigned int vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, ' ');
-
- float x = ParseOBJFloatValue(line, vertIndexStart, vertIndexEnd);
-
- vertIndexStart = vertIndexEnd + 1;
- vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, ' ');
-
- float y = ParseOBJFloatValue(line, vertIndexStart, vertIndexEnd);
-
- vertIndexStart = vertIndexEnd + 1;
- vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, ' ');
-
- float z = ParseOBJFloatValue(line, vertIndexStart, vertIndexEnd);
-
- return glm::vec3(x, y, z);
-}
-
-glm::vec2
-OBJModel::ParseOBJVec2(const std::string & line)
-{
- unsigned int tokenLength = line.length();
- const char * tokenString = line.c_str();
-
- unsigned int vertIndexStart = 3;
-
- while (vertIndexStart < tokenLength) {
- if (tokenString[vertIndexStart] != ' ') {
- break;
- }
- vertIndexStart++;
- }
-
- unsigned int vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, ' ');
-
- float x = ParseOBJFloatValue(line, vertIndexStart, vertIndexEnd);
-
- vertIndexStart = vertIndexEnd + 1;
- vertIndexEnd = FindNextChar(vertIndexStart, tokenString, tokenLength, ' ');
-
- float y = ParseOBJFloatValue(line, vertIndexStart, vertIndexEnd);
-
- return glm::vec2(x, y);
-}
-
-static bool
-CompareOBJIndexPtr(const OBJIndex * a, const OBJIndex * b)
-{
- return a->vertexIndex < b->vertexIndex;
-}
-
-static inline unsigned int
-FindNextChar(unsigned int start, const char * str, unsigned int length, char token)
-{
- unsigned int result = start;
- while (result < length) {
- result++;
- if (str[result] == token) {
- break;
- }
- }
-
- return result;
-}
-
-static inline unsigned int
-ParseOBJIndexValue(const std::string & token, unsigned int start, unsigned int end)
-{
- return std::stoul(token.substr(start, end - start)) - 1;
-}
-
-static inline float
-ParseOBJFloatValue(const std::string & token, unsigned int start, unsigned int end)
-{
- return std::stof(token.substr(start, end - start));
-}
-
-static inline std::vector<std::string>
-SplitString(const std::string & s, char delim)
-{
- std::vector<std::string> elems;
-
- const char * cstr = s.c_str();
- unsigned int strLength = s.length();
- unsigned int start = 0;
- unsigned int end = 0;
-
- while (end <= strLength) {
- while (end <= strLength) {
- if (cstr[end] == delim) {
- break;
- }
- end++;
- }
-
- elems.push_back(s.substr(start, end - start));
- start = end + 1;
- end = start;
- }
-
- return elems;
-}
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