/* I seem to need this for glGenBuffers as per
   http://www.gamedev.net/community/forums/topic.asp?topic_id=422358 */
#define GL_GLEXT_PROTOTYPES

#include "exp004base.h"
#include "../view/exp004state0.h"
#include <GL/glut.h>
#include <stdio.h>
#include <string.h>

void
exp004base (void)
{
  /*
   * A simple alias to make the code more readable.
   */
  EXP004STATE* S = &exp004state0;

  /* 
   * This implementation can be improved by mapping the video memory
   * directly rather than loading into system memory and then copying
   * into video memory.
  */

  FILE* coords = 
    fopen ("/home/don/exp004/test/run20090514/run20090514.coords", "r");
  int i = 0;

  /* 
   * Initialize the bounding box of the points.
   */
  S->bb.min_x = 0.0;
  S->bb.max_x = 0.0;
  S->bb.min_y = 0.0;
  S->bb.max_y = 0.0;

  for (i = 0; i < ROWS; i++)
    {
      fscanf (coords, "%s %f %f\n",
	      S->gi_data[i],
	      &S->base_vertices_data[i][0],
	      &S->base_vertices_data[i][1]);

      if (S->base_vertices_data[i][0] < S->bb.min_x)
	S->bb.min_x = S->base_vertices_data[i][0];
      if (S->base_vertices_data[i][0] > S->bb.max_x)
	S->bb.max_x = S->base_vertices_data[i][0];
      if (S->base_vertices_data[i][1] < S->bb.min_y)
	S->bb.min_y = S->base_vertices_data[i][1];
      if (S->base_vertices_data[i][1] > S->bb.max_y)
	S->bb.max_y = S->base_vertices_data[i][1];

      /*
       * Deselected by default.
       */
      S->selection[i] = false;

      S->base_colors_data[i][0] = DEFAULT_COLOR_R;
      S->base_colors_data[i][1] = DEFAULT_COLOR_G;
      S->base_colors_data[i][2] = DEFAULT_COLOR_B;
    }
  fclose (coords);

  /*
   * Find the largest axis and use it to setup the projection.  This
   * is done to preserve the aspect ratio.  The aspect ratio should be
   * preserved since relative distance is a meaningful indicator in
   * the map.
   */

  // Min of min x or min y.
  if (S->bb.min_x <= S->bb.min_y)
    S->ortho_min = S->bb.min_x;
  else
    S->ortho_min = S->bb.min_y;
  S->ortho_min--;

  // Max of max x or max y.
  if (S->bb.max_x >= S->bb.max_y)
    S->ortho_max = S->bb.max_x;
  else
    S->ortho_max = S->bb.max_y;
  S->ortho_max++;

  // Invert the y coordinate to match up with the LGL Java viewer.
  for (i = 0; i < ROWS; i++)
    S->base_vertices_data[i][1] = 
      S->ortho_max - S->base_vertices_data[i][1];

  S->points = i;

  glGenBuffers (2, S->buffers);

  glBindBuffer (GL_ARRAY_BUFFER, S->buffers[BASE_VERTICES]);
  glVertexPointer (2, GL_FLOAT, 0, 0);
  glBufferData (GL_ARRAY_BUFFER, 
		sizeof (S->base_vertices_data), S->base_vertices_data,
		GL_STATIC_DRAW);

  glBindBuffer (GL_ARRAY_BUFFER, S->buffers[BASE_COLORS]);
  glColorPointer (3, GL_FLOAT, 0, 0);
  glBufferData (GL_ARRAY_BUFFER,
		sizeof (S->base_colors_data), S->base_colors_data,
		GL_STATIC_DRAW);

  return;
}