1 files changed, 109 insertions, 0 deletions

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+#include "mesh.h"
+#include <fstream>
+#include <vector>
+#include <map>
+#include <glm/glm.hpp>
+#include "util.h"
+
+Mesh::Mesh(std::string filename)
+{
+  std::ifstream meshfile(filename);
+  if (!meshfile.is_open())
+  {
+    throw std::invalid_argument("Could not open mesh file");
+  }
+
+  std::vector<glm::vec3> tempVertices;
+  std::vector<glm::vec2> tempUvs;
+  std::vector<glm::vec3> tempNormals;
+
+  std::vector<glm::vec3> outVertices;
+  std::vector<glm::vec2> outUvs;
+  std::vector<glm::vec3> outNormals;
+  std::map<element, unsigned short> elementIds;
+  std::vector<unsigned short> indices;
+
+  while (meshfile)
+  {
+    std::string linetype;
+    meshfile >> linetype;
+
+    if (linetype == "v")
+    {
+      glm::vec3 vertex;
+      meshfile >> vertex.x >> vertex.y >> vertex.z;
+
+      tempVertices.push_back(std::move(vertex));
+    } else if (linetype == "vt")
+    {
+      glm::vec2 uv;
+      meshfile >> uv.x >> uv.y;
+
+      tempUvs.push_back(std::move(uv));
+    } else if (linetype == "vn")
+    {
+      glm::vec3 normal;
+      meshfile >> normal.x >> normal.y >> normal.z;
+
+      tempNormals.push_back(std::move(normal));
+    } else if (linetype == "f")
+    {
+      element elements[3];
+
+      meshfile
+        >> elements[0].vertexId >> chlit('/')
+        >> elements[0].uvId >> chlit('/')
+        >> elements[0].normalId
+        >> elements[1].vertexId >> chlit('/')
+        >> elements[1].uvId >> chlit('/')
+        >> elements[1].normalId
+        >> elements[2].vertexId >> chlit('/')
+        >> elements[2].uvId >> chlit('/')
+        >> elements[2].normalId;
+
+      for (size_t i = 0; i < 3; i++)
+      {
+        if (!elementIds.count(elements[i]))
+        {
+          elementIds[elements[i]] = outVertices.size();
+
+          outVertices.push_back(tempVertices[elements[i].vertexId - 1]);
+          outUvs.push_back(tempUvs[elements[i].uvId - 1]);
+          outNormals.push_back(tempNormals[elements[i].normalId - 1]);
+        }
+
+        indices.push_back(elementIds[elements[i]]);
+      }
+    }
+  }
+
+  glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer_.getId());
+  glBufferData(
+    GL_ARRAY_BUFFER,
+    outVertices.size() * sizeof(glm::vec3),
+    outVertices.data(),
+    GL_STATIC_DRAW);
+
+  glBindBuffer(GL_ARRAY_BUFFER, uvBuffer_.getId());
+  glBufferData(
+    GL_ARRAY_BUFFER,
+    outUvs.size() * sizeof(glm::vec2),
+    outUvs.data(),
+    GL_STATIC_DRAW);
+
+  glBindBuffer(GL_ARRAY_BUFFER, normalBuffer_.getId());
+  glBufferData(
+    GL_ARRAY_BUFFER,
+    outNormals.size() * sizeof(glm::vec3),
+    outNormals.data(),
+    GL_STATIC_DRAW);
+
+  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer_.getId());
+  glBufferData(
+    GL_ELEMENT_ARRAY_BUFFER,
+    indices.size() * sizeof(unsigned short),
+    indices.data(),
+    GL_STATIC_DRAW);
+
+  indexCount_ = indices.size();
+}