model.cpp

   1 #include "model.hpp"
   2 #include <iostream>
   3 #include <assimp/postprocess.h>
   4 #include <assimp/quaternion.h>
   5 #include <glm/gtc/type_ptr.hpp>
   6
   7 glm::mat4 aiMatrixToMat4(aiMatrix4x4 from) {
   8         glm::mat4 to;
   9         for (int i = 0; i < 4; i++)
  10                 for (int j = 0; j < 4; j++)
  11                         to[i][j] = from[j][i];
  12         return to;
  13 }
  14
  15
  16 Model::Mesh::Mesh(const aiMesh *aiMesh, GLuint progId) {
  17
  18         std::vector<glm::vec3> vertices, normals, tangents, bitangents;
  19         std::vector<glm::vec2> texCoords;
  20
  21         for (int i = 0; i < aiMesh->mNumVertices; i++) {
  22                 if (aiMesh->HasPositions()) {
  23                         aiVector3D v = aiMesh->mVertices[i];
  24                         vertices.push_back(glm::vec3(v.x, v.y, v.z));
  25                 }
  26                 if (aiMesh->HasNormals()) {
  27                         aiVector3D v = aiMesh->mNormals[i];
  28                         normals.push_back(glm::vec3(v.x, v.y, v.z));
  29                 } else {
  30                         std::cerr << "Missing normals" << std::endl;
  31                         exit(1);
  32                 }
  33                 // check for texture coord set 0
  34                 if (aiMesh->HasTextureCoords(0)) {
  35                         const aiVector3D v = aiMesh->mTextureCoords[0][i];
  36                         texCoords.push_back(glm::vec2(v.x, v.y));
  37                 } else {
  38                         texCoords.push_back(glm::vec2(0));
  39                 }
  40                 materialIndex = aiMesh->mMaterialIndex;
  41         }
  42
  43         std::vector<GLuint> indices;
  44
  45         for (int i = 0; i < aiMesh->mNumFaces; i++) {
  46                 const aiFace &face = aiMesh->mFaces[i];
  47                 if(face.mNumIndices == 3) {
  48                         indices.push_back(face.mIndices[0]);
  49                         indices.push_back(face.mIndices[1]);
  50                         indices.push_back(face.mIndices[2]);
  51                 }
  52         }
  53
  54         numIndices = indices.size();
  55
  56         glGenVertexArrays(1, &vao);
  57         glBindVertexArray(vao);
  58
  59         GLuint vbos[6];
  60         glGenBuffers(6, vbos);
  61         GLuint vertexVbo = vbos[0], normalVbo = vbos[1], texCoordVbo = vbos[2], indicesVbo = vbos[3];
  62         GLuint boneVbo = vbos[4];
  63
  64         GLuint posLoc = glGetAttribLocation(progId, "pos");
  65         glBindBuffer(GL_ARRAY_BUFFER, vertexVbo);
  66         glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(glm::vec3), &vertices[0], GL_STATIC_DRAW);
  67         glEnableVertexAttribArray(posLoc);
  68         glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
  69
  70         GLuint normalLoc = glGetAttribLocation(progId, "unscaledNormal");
  71         glBindBuffer(GL_ARRAY_BUFFER, normalVbo);
  72         glBufferData(GL_ARRAY_BUFFER, normals.size() * sizeof(glm::vec3), &normals[0], GL_STATIC_DRAW);
  73         glEnableVertexAttribArray(normalLoc);
  74         glVertexAttribPointer(normalLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
  75
  76         GLuint texCoordLoc = glGetAttribLocation(progId, "vTexCoord");
  77         glBindBuffer(GL_ARRAY_BUFFER, texCoordVbo);
  78         glBufferData(GL_ARRAY_BUFFER, texCoords.size() * sizeof(glm::vec2), &texCoords[0], GL_STATIC_DRAW);
  79         glEnableVertexAttribArray(texCoordLoc);
  80         glVertexAttribPointer(texCoordLoc, 2, GL_FLOAT, GL_FALSE, 0, 0);
  81
  82         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indicesVbo);
  83         glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(GLuint), &indices[0], GL_STATIC_DRAW);
  84
  85         // bones
  86         std::vector<VertBones> vertBones(aiMesh->mNumVertices);
  87
  88         std::map<unsigned int, std::vector<std::pair<unsigned int, float>>> boneWeightMap;
  89
  90         for (unsigned int i = 0; i < aiMesh->mNumBones; i++) {
  91                 aiBone *aiBone = aiMesh->mBones[i];
  92
  93                 boneMap[std::string(aiBone->mName.C_Str())] = std::pair(i + 1, aiMatrixToMat4(aiBone->mOffsetMatrix));
  94
  95                 for (int j = 0; j < aiBone->mNumWeights; j++) {
  96                         aiVertexWeight vw = aiBone->mWeights[j];
  97
  98                         if (!boneWeightMap.count(vw.mVertexId)) boneWeightMap[vw.mVertexId] = std::vector<std::pair<unsigned int, float>>();
  99                         boneWeightMap[vw.mVertexId].push_back(std::pair(i + 1, vw.mWeight));
 100                 }
 101         }
 102
 103         for (auto pair: boneWeightMap) {
 104                 unsigned int vertexId = pair.first;
 105                 for (int i = 0; i < pair.second.size() && i < 4; i++) {
 106                         unsigned int boneId = pair.second[i].first;
 107                         float weight = pair.second[i].second;
 108                         vertBones[vertexId].ids[i] = boneId;
 109                         vertBones[vertexId].weights[i] = weight;
 110                 }
 111         }
 112
 113         glBindBuffer(GL_ARRAY_BUFFER, boneVbo);
 114         glBufferData(GL_ARRAY_BUFFER, sizeof(VertBones) * vertBones.size(), &vertBones[0], GL_STATIC_DRAW);
 115
 116         GLuint boneIdLoc = glGetAttribLocation(progId, "boneIds");
 117         glEnableVertexAttribArray(boneIdLoc);
 118         glVertexAttribIPointer(boneIdLoc, 4, GL_INT, sizeof(VertBones), 0);
 119
 120         GLuint boneWeightLoc = glGetAttribLocation(progId, "boneWeights");
 121         glEnableVertexAttribArray(boneWeightLoc);
 122         glVertexAttribPointer(boneWeightLoc, 4, GL_FLOAT, GL_FALSE, sizeof(VertBones), (const GLvoid *)sizeof(VertBones::ids));
 123 }
 124
 125 Model::Node::Node(const aiNode &node, GLuint progId, AnimMap *am): ai(node), progId(progId), animMap(am) {
 126         for (int i = 0; i < node.mNumMeshes; i++) {
 127                 meshIndices.push_back(node.mMeshes[i]);
 128         }
 129         for (int i = 0; i < node.mNumChildren; i++) {
 130                 const aiNode *child = node.mChildren[i];
 131                 children.push_back(new Node(*child, progId, am));
 132         }
 133 }
 134
 135 glm::mat4 lerp(const aiNodeAnim *anim, const float tick) {
 136
 137         if (anim->mNumPositionKeys == 0) return glm::mat4(1.f);
 138
 139         int yIndex = -1;
 140         for (int i = 0; i < anim->mNumPositionKeys; i++) {
 141                 aiVectorKey vk = anim->mPositionKeys[i];
 142                 if (vk.mTime > tick) {
 143                         yIndex = i;
 144                         break;
 145                 }
 146         }
 147         aiVector3D lerpPos;
 148         if (yIndex < 1) {
 149                 lerpPos = anim->mPositionKeys[0].mValue;
 150         } else {
 151                 auto X = anim->mPositionKeys[yIndex - 1];
 152                 auto Y = anim->mPositionKeys[yIndex];
 153
 154                 lerpPos = (X.mValue * (float)(Y.mTime - tick) + Y.mValue * (float)(tick - X.mTime)) / (float)(Y.mTime - X.mTime);
 155         }
 156         aiMatrix4x4 result;
 157         aiMatrix4x4::Translation(lerpPos, result);
 158         return aiMatrixToMat4(result);
 159 }
 160
 161 glm::mat4 lerpRotation(const aiNodeAnim *anim, const float tick) {
 162         int yIndex = -1;
 163         for (int i = 0; i < anim->mNumRotationKeys; i++) {
 164                 aiQuatKey vk = anim->mRotationKeys[i];
 165                 if (vk.mTime > tick) {
 166                         yIndex = i;
 167                         break;
 168                 }
 169         }
 170
 171         aiQuaternion result;
 172         if (yIndex < 1) {
 173                 result = anim->mRotationKeys[0].mValue;
 174         } else {
 175
 176                 auto X = anim->mRotationKeys[yIndex - 1];
 177                 auto Y = anim->mRotationKeys[yIndex];
 178
 179                 float mix = (tick - X.mTime) / (Y.mTime - X.mTime);
 180
 181                 aiQuaternion::Interpolate(result, X.mValue, Y.mValue, mix);
 182
 183         }
 184         return aiMatrixToMat4(aiMatrix4x4(result.GetMatrix()));
 185 }
 186
 187 glm::mat4 lerpScaling(const aiNodeAnim *anim, const float tick) {
 188         int yIndex = -1;
 189         for (int i = 0; i < anim->mNumScalingKeys; i++) {
 190                 aiVectorKey vk = anim->mScalingKeys[i];
 191                 if (vk.mTime > tick) {
 192                         yIndex = i;
 193                         break;
 194                 }
 195         }
 196
 197         aiVector3D lerpPos;
 198         if (yIndex < 1) {
 199                 lerpPos = anim->mScalingKeys[0].mValue;
 200         } else {
 201                 auto X = anim->mScalingKeys[yIndex - 1];
 202                 auto Y = anim->mScalingKeys[yIndex];
 203
 204                 lerpPos = (X.mValue * (float)(Y.mTime - tick) + Y.mValue * (float)(tick - X.mTime)) / (float)(Y.mTime - X.mTime);
 205         }
 206         aiMatrix4x4 result;
 207         aiMatrix4x4::Scaling(lerpPos, result);
 208         return aiMatrixToMat4(result);
 209 }
 210
 211 void Model::Node::draw( const std::vector<Mesh> &meshes,
 212                                                 const std::vector<Material> &materials,
 213                                                 const Skybox skybox,
 214                                                 const float tick,
 215                                                 glm::mat4 parentTrans = glm::mat4(1),
 216                                                 BoneTransforms boneTransforms = BoneTransforms()) const {
 217
 218         GLuint modelLoc = glGetUniformLocation(progId, "model");
 219
 220         glm::mat4 animTrans(1.f);
 221         if (animMap->count(std::string(ai.mName.C_Str()))) {
 222                 for (const Animation anim: animMap->at(std::string(ai.mName.C_Str()))) {
 223                         float t = fmod(tick, anim.duration);
 224                         for (const aiNodeAnim *nodeAnim: anim.nodeAnims) {
 225                                 animTrans *= lerp(nodeAnim, t);
 226                                 animTrans *= lerpRotation(nodeAnim, t);
 227                                 animTrans *= lerpScaling(nodeAnim, t);
 228                         }
 229                 }
 230                 /* std::cerr << std::string(ai.mName.C_Str()) << animTrans[0][0] << std::endl; */
 231         }
 232
 233
 234         glm::mat4 m = parentTrans * animTrans * aiMatrixToMat4(ai.mTransformation) * model;
 235
 236         for (auto child: children) {
 237                 //set to parent transforms
 238                 boneTransforms[std::string(ai.mName.C_Str())] = m;
 239         }
 240
 241         for (unsigned int i: meshIndices) {
 242                 const Mesh &mesh = meshes[i];
 243                 glBindVertexArray(mesh.vao);
 244
 245                 // bones
 246                 std::vector<glm::mat4> idBones(17, glm::mat4(1.f));
 247                 glUniformMatrix4fv(glGetUniformLocation(progId, "bones"), 17, GL_FALSE, glm::value_ptr(idBones[0]));
 248
 249                 for (std::pair<std::string, std::pair<unsigned int, glm::mat4>> pair: mesh.boneMap) {
 250
 251                         std::string nodeName = pair.first;
 252                         unsigned int boneId = pair.second.first;
 253                         glm::mat4 boneOffset = pair.second.second;
 254
 255                         glm::mat4 boneTrans(1.f);
 256                         if (boneTransforms.count(nodeName)) boneTrans = boneTransforms[nodeName];
 257                         int j = 0;
 258                         for (const Animation anim: animMap->at(nodeName)) {
 259                                 float t = fmod(tick, anim.duration);
 260                                 for (const aiNodeAnim *nodeAnim: anim.nodeAnims) {
 261                                         boneTrans = boneTrans * lerp(nodeAnim, t);
 262                                         boneTrans = boneTrans * lerpRotation(nodeAnim, t);
 263                                         /* boneTrans = boneTrans * lerpScaling(nodeAnim, t); */
 264                                         j++;
 265                                 }
 266                         }
 267                         assert(j == 1);
 268
 269
 270                         boneTrans = boneTrans * glm::inverse(boneOffset);
 271
 272
 273                         std::string boneLocStr = "bones[" + std::to_string(boneId) + "]";
 274                         GLuint boneLoc = glGetUniformLocation(progId, boneLocStr.c_str());
 275                         glUniformMatrix4fv(boneLoc, 1, GL_FALSE, glm::value_ptr(boneTrans));
 276                 }
 277
 278                 Material material = materials[mesh.materialIndex];
 279                 material.bind();
 280
 281                 glUniform1i(glGetUniformLocation(progId, "irradianceMap"), 4);
 282                 glActiveTexture(GL_TEXTURE4);
 283                 glBindTexture(GL_TEXTURE_CUBE_MAP, skybox.getIrradianceMap());
 284
 285                 glUniform1i(glGetUniformLocation(progId, "prefilterMap"), 5);
 286                 glActiveTexture(GL_TEXTURE5);
 287                 glBindTexture(GL_TEXTURE_CUBE_MAP, skybox.getPrefilterMap());
 288
 289                 glUniform1i(glGetUniformLocation(progId, "brdfMap"), 6);
 290                 glActiveTexture(GL_TEXTURE6);
 291                 glBindTexture(GL_TEXTURE_2D, skybox.getBRDFMap());
 292
 293                 glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(m));
 294
 295                 glDrawElements(GL_TRIANGLES, mesh.numIndices, GL_UNSIGNED_INT, 0);
 296         }
 297         for (Node *child: children) child->draw(meshes, materials, skybox, tick, m, boneTransforms);
 298 }
 299
 300 Model::Model(const std::string &path, Program p): program(p) {
 301         glUseProgram(p.progId);
 302
 303         const aiScene *scene = importer.ReadFile(path,
 304                         aiProcess_Triangulate | aiProcess_CalcTangentSpace | aiProcess_GenNormals | aiProcess_FlipUVs);
 305         if (!scene) {
 306                 std::cerr << importer.GetErrorString() << std::endl;
 307                 exit(1);
 308         }
 309
 310         for (int i = 0; i < scene->mNumMeshes; i++) {
 311                 const aiMesh *mesh = scene->mMeshes[i];
 312                 meshes.push_back(Mesh(mesh, p.progId));
 313         }
 314
 315         // TODO: handle default material inserted at the end by assimp
 316         for (unsigned int i = 0; i < scene->mNumMaterials - 1; i++) {
 317                 const aiMaterial &material = *scene->mMaterials[i];
 318                 materials.push_back(Material(material, p.progId));
 319         }
 320
 321         AnimMap *animMap = new AnimMap();
 322         for (int i = 0; i < scene->mNumAnimations; i++) {
 323                 const aiAnimation *aiAnim = scene->mAnimations[i];
 324
 325                 std::map<std::string, std::vector<const aiNodeAnim*>> nodeAnims;
 326
 327                 for (int j = 0; j < aiAnim->mNumChannels; j++) {
 328                         const aiNodeAnim *nodeAnim = aiAnim->mChannels[j];
 329                         std::string nodeName = std::string(nodeAnim->mNodeName.C_Str());
 330
 331                         if (!nodeAnims.count(nodeName)) nodeAnims[nodeName] = std::vector<const aiNodeAnim*>();
 332
 333                         nodeAnims[nodeName].push_back(nodeAnim);
 334                 }
 335
 336                 for (std::pair<std::string, std::vector<const aiNodeAnim*>> pair: nodeAnims) {
 337                         std::string nodeName = pair.first;
 338
 339                         if (!animMap->count(nodeName)) (*animMap)[nodeName] = std::vector<const Animation>();
 340                         (*animMap)[nodeName].push_back({ 7500, pair.second });
 341                 }
 342         }
 343
 344         root = new Node(*(scene->mRootNode), p.progId, animMap);
 345 }
 346
 347 void Model::draw(Skybox skybox, const float tick) const {
 348         glUseProgram(program.progId);
 349         root->draw(meshes, materials, skybox, tick);
 350 }
 351
 352 Model::Node* Model::find(const std::string &name) {
 353         return find(aiString(name));
 354 }
 355
 356 Model::Node* Model::find(const aiString name) {
 357         const aiNode *node = root->ai.FindNode(name);
 358         Model::Node* res = root->findNode(*node);
 359         return res;
 360 }
 361
 362 Model::Node* Model::Node::findNode(const aiNode &aiNode) {
 363         if (&ai == &aiNode) return this;
 364         for (Model::Node *child: children) {
 365                 Model::Node *res = child->findNode(aiNode);
 366                 if (res) return res;
 367         }
 368         return nullptr;
 369 }