#include <gl/tinygl.h>
#include <stdio.h>
#include <stdbool.h>

void gl_write_image (FILE * fp, const GLubyte * buffer,
		     unsigned width, unsigned height, unsigned samples);
void gl_write_image_png (FILE * fp, const GLubyte * buffer,
			 unsigned width, unsigned height, unsigned samples);
void init_gl();

void matrix_multiply (float * m, const float * n);
void vector_multiply (float * v, const float * m);

typedef struct {
  float m[16], p[16];
  float n[6][3];
  float d[6];
  unsigned width;
} Frustum;

void gl_get_frustum (Frustum * f);
int sphere_in_frustum (double x, double y, double z, double r, Frustum * f);
float sphere_diameter (double x, double y, double z, double r, Frustum * f);
void gl_check_error();

int polygonize (const double val[8], double isolevel, double triangles[5][3][3]);
void gl_perspective (double fovy, double aspect, double zNear, double zFar);
int gl_project (float objx, float objy, float objz, 
		const float modelMatrix[16], 
		const float projMatrix[16],
		const GLint viewport[4],
		float *winx, float *winy, float *winz);

#include "parser.h"