Init.HEADmaster

1 files changed, 152 insertions, 0 deletions

diff --git a/hw6/src/importOBJ.cpp b/hw6/src/importOBJ.cpp
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--- /dev/null
+++ b/hw6/src/importOBJ.cpp
@@ -0,0 +1,152 @@
+/******************************************************************/
+/* This file is part of the homework assignments for CSCI-427/527 */
+/* at The College of William & Mary and authored by Pieter Peers. */
+/* No part of this file, whether altered or in original form, can */
+/* be distributed or used outside the context of CSCI-427/527     */
+/* without consent of either the College of William & Mary or     */
+/* Pieter Peers.                                                  */
+/******************************************************************/
+
+#include <memory>
+#include <string>
+#include <cassert>
+#include <fstream>
+
+#include "vec3d.h"
+#include "vec2d.h"
+#include "importOBJ.h"
+#include "errorMessage.h"
+
+void skipLine(std::ifstream& ifs)
+{
+  unsigned char c = ifs.get();
+  while(ifs.good() && c != '\r' && c != '\n') c = ifs.get();
+  while(ifs.good() && (c == '\r' || c == '\n')) c = ifs.get();
+  ifs.unget();
+}
+
+void importOBJ(const std::string filename, std::vector<triangle>& triangle_list)
+{
+  // define buffers
+  auto vertex_list = std::make_shared<std::vector<vec3d>>();
+  auto normal_list = std::make_shared<std::vector<vec3d>>();
+  auto textureCoord_list = std::make_shared<std::vector<vec2d>>();
+
+  // open obj file
+  std::ifstream ifs(filename, std::ifstream::in | std::ifstream::binary);
+  if(!ifs.is_open()) 
+    errorMessage("Unable to import OBJ (%s).", filename.c_str());
+
+  // read line by line
+  unsigned char key;
+  while(ifs.good())
+  {
+    // get key
+    key = ifs.get();
+
+    // VERTEX DATA:
+    if(key == 'v')
+    {
+      // get vertex data
+      key = ifs.get();
+
+      // Vertex Coordinate
+      if(key == ' ') 
+      {
+	vec3d v;
+	ifs >> v.x >> v.y >> v.z;
+	vertex_list->push_back(v);
+      }
+
+      // Texture Coordinate
+      else if(key == 't')
+      {
+	vec2d t;
+	ifs >> t.u >> t.v;
+	textureCoord_list->push_back(t);
+      }
+
+      // Normal
+      else if(key == 'n')  
+      {
+	vec3d n;
+	ifs >> n.x >> n.y >> n.z;
+	normal_list->push_back(n);
+      }
+
+      // Unknown => ERROR
+      else errorMessage("Unknown OBJ vertex-key: v%c.", key);
+    }
+
+    // POLYGON:
+    else if(key == 'f')
+    {
+      // temp data structures 
+      std::vector<unsigned int> vidx;
+      std::vector<unsigned int> nidx;
+      std::vector<unsigned int> tidx;
+
+      // get polygon data
+      // can be either: 
+      // 1)  v0 v1 .. vn
+      // 2)  v0//n0 v1//n1 .. vn//nn
+      // 3)  v0/t0 v1/t1 ... vn/tn
+      // 4)  v0/t0/n0 ... vn/tn/nn
+      bool done=false;
+      while(!done)
+      {
+	// read entry
+	signed int vi, vt=-1, vn=-1;
+	ifs >> vi;
+	unsigned char c = ifs.get();
+
+	if(c == '/')
+	{
+	  c = ifs.get();
+	  if(c != '/') { ifs.unget(); ifs >> vt; c = ifs.get(); }
+	  if(c == '/') { ifs >> vn; c = ifs.get(); }
+	}
+
+	// sanity check
+	assert(vt != 0 && vn != 0 && vi != 0);
+
+	// store in polygon
+        if(vt != -1) { assert(vt-1 < textureCoord_list->size()); tidx.push_back(vt-1); }
+        if(vn != -1) { assert(vn-1 < normal_list->size()); nidx.push_back(vn-1); }
+	if(vi != -1) { assert(vi-1 < vertex_list->size()); vidx.push_back(vi-1); }
+
+	// eat spaces and end-of-lines
+	ifs.unget();
+	c = ifs.get();
+	while(ifs.good() && (c == ' ' ||c == '\r' || c == '\n'))
+	{
+	  if(c == '\r' || c == '\n') done = true;
+	  c = ifs.get();
+	}
+	ifs.unget();
+
+        // sanity check
+        assert(tidx.empty() || tidx.size() == vidx.size());
+        assert(nidx.empty() || nidx.size() == vidx.size());
+
+        // store triangle
+        if(vidx.size() >= 3)
+        {
+          size_t m=vidx.size() - 2;
+          size_t l=vidx.size() - 1;
+          if(tidx.empty() && nidx.empty()) triangle_list.push_back( triangle(vidx[0], vidx[m], vidx[l], vertex_list) );
+          if(tidx.empty() && !nidx.empty()) triangle_list.push_back( triangle(vidx[0], vidx[m], vidx[l], vertex_list,
+									      nidx[0], nidx[m], nidx[l], normal_list) );
+          if(!tidx.empty() && nidx.empty()) triangle_list.push_back( triangle(vidx[0], vidx[m], vidx[l], vertex_list,
+									      tidx[0], tidx[m], tidx[l], textureCoord_list) );
+          if(!tidx.empty() && !nidx.empty()) triangle_list.push_back( triangle(vidx[0], vidx[m], vidx[l], vertex_list,
+									       nidx[0], nidx[m], nidx[l], normal_list,
+									       tidx[0], tidx[m], tidx[l], textureCoord_list) );
+        }
+      }
+    }
+    else { ifs.unget(); skipLine(ifs); }
+  }
+
+  // Done.
+}