// PhilVaz ASC Model Loading Demo
// Put model.asc in same folder as .exe
// change the file name to model.asc
// NOTE: only reads in first Named object of model
// Nov 5, 2004

#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
#include <process.h>  // for exit()

#define MAX_BUF     255
#define MAX_VERT  99999
#define MAX_LINES    61

FILE *file = NULL;           // file handle
char line[MAX_BUF];          // line buffer
int page_lines = 0;          // lines per page
int total_tris = 0;          // total triangles (polygons)

float verts[MAX_VERT][3];    // vertex array
int   tris[MAX_VERT][3];     // triangles array (index to verts)

void WaitForKey();
void ExitError(int);
void ReadALine();

void main()
{

   int i = 0, j = 0;   // loop counters
   int v = 0, f = 0;   // vertices and faces (triangles)

   float x = 0.0, y = 0.0, z = 0.0;  // temp X Y Z vertex
   int a = 0, b = 0, c = 0;          // temp A B C face

   file = fopen("model.asc","r");    // open the model file
   
   if (file == NULL) ExitError(1);
   printf("File model.asc opened ok\n");
      
   ReadALine();  // read Ambient light line
   ReadALine();  // read blank line
   ReadALine();  // read Named object line
   
   ReadALine();  // read # vertices and faces line
   sscanf(line, "Tri-mesh, Vertices: %d Faces: %d", &v, &f);
   printf("Verts = %d  Faces = %d\n", v, f);
         
   if (v == 0 || f == 0) ExitError(2);
   if (v > MAX_VERT || f > MAX_VERT) ExitError(3);
         
   ReadALine(); // read Vertex list line

   for (i = 0; i < v; i++)
   {
      ReadALine();  // read X Y Z vertex point
      sscanf(line, "Vertex %d: X:%f Y:%f Z:%f", &j, &x, &y, &z);
      // save the vertex point in array            
      verts[i][0] = x; verts[i][1] = y; verts[i][2] = z;
   }
   
   printf("Last Vertex line read: X = %f   Y = %f   Z = %f\n", x, y, z);
   
   ReadALine();  // read Face list line
   
   total_tris += f;
   if (total_tris > MAX_VERT) ExitError(3);
   
   for (i = 0; i < f; i++)
   {
      ReadALine();  // read A B C face (index to vertex array)
      sscanf(line, "Face %d: A:%d B:%d C:%d", &j, &a, &b, &c);
      // save the face indexes (triangles) in array            
      tris[i][0] = a; tris[i][1] = b; tris[i][2] = c;
      
      ReadALine();  // read Material line
      ReadALine();  // read Smoothing line
   }
      
   fclose(file);
   
   printf("Last Face line read: A = %d   B = %d   C = %d\n", a, b, c);
   
   ExitError(0);
         
} // END OF main


void ExitError(int n)
{

   if (n == 0) printf("No Errors! Reached end of program!\n\n");
   if (n == 1) printf("Error: File not opened\n\n");
   if (n == 2) printf("Error: Faces or Vertices = 0\n\n");
   if (n == 3) printf("Error: greater than 100,000 Polygons\n\n");
            
   if (file) fclose(file);
      
   WaitForKey();
   exit(0);
   
} // END OF ExitError


void ReadALine()
{
   char temp[MAX_BUF];
   
   fgets(line, MAX_BUF, file);
         
   page_lines++;
   if (page_lines == MAX_LINES) // we hit end of page
   {
      page_lines = 0;
      fgets(temp, MAX_BUF, file);  // read a line
      fgets(temp, MAX_BUF, file);  // read a line
      fgets(temp, MAX_BUF, file);  // read a line
      fgets(temp, MAX_BUF, file);  // read a line
      fgets(temp, MAX_BUF, file);  // read a line
   }

} // END OF ReadALine


void WaitForKey()
{

   printf("Waiting for key...\n");
   do
   {
      // nothing
   } while (!kbhit());
         
   return;

} // END OF WaitForKey