src/glu/mini/nurbs.h

/* $Id: nurbs.h,v 1.2 2003-08-22 20:11:43 brianp Exp $ */

/*
 * Mesa 3-D graphics library
 * Version:  3.3
 * Copyright (C) 1995-2000  Brian Paul
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


/*
 * NURBS implementation written by Bogdan Sikorski (bogdan@cira.it)
 * See README2 for more info.
 */


#ifndef NURBS_H
#define NURBS_H


#define EPSILON 1e-06		/* epsilon for double precision compares */

typedef enum
{
   GLU_NURBS_CURVE, GLU_NURBS_SURFACE, GLU_NURBS_TRIM, GLU_NURBS_NO_TRIM,
   GLU_NURBS_TRIM_DONE, GLU_NURBS_NONE
}
GLU_nurbs_enum;

typedef enum
{
   GLU_TRIM_NURBS, GLU_TRIM_PWL
}
GLU_trim_enum;

typedef struct
{
   GLint sknot_count;
   GLfloat *sknot;
   GLint tknot_count;
   GLfloat *tknot;
   GLint s_stride;
   GLint t_stride;
   GLfloat *ctrlarray;
   GLint sorder;
   GLint torder;
   GLint dim;
   GLenum type;
}
surface_attribs;

typedef struct
{
   surface_attribs geom;
   surface_attribs color;
   surface_attribs texture;
   surface_attribs normal;
}
nurbs_surface;

typedef struct
{
   GLint knot_count;
   GLfloat *knot;
   GLint stride;
   GLfloat *ctrlarray;
   GLint order;
   GLint dim;
   GLenum type;
}
curve_attribs;

typedef struct
{
   GLint pt_count;
   GLfloat *ctrlarray;
   GLint stride;
   GLint dim;
   GLenum type;
}
pwl_curve_attribs;

typedef struct
{
   curve_attribs geom;
   curve_attribs color;
   curve_attribs texture;
   curve_attribs normal;
}
nurbs_curve;

typedef struct trim_list_str
{
   GLU_trim_enum trim_type;
   union
   {
      pwl_curve_attribs pwl_curve;
      curve_attribs nurbs_curve;
   }
   curve;
   struct trim_list_str *next;
}
trim_list;

typedef struct seg_trim_str
{
   GLfloat *points;
   GLint pt_cnt, seg_array_len;
   struct seg_trim_str *next;
}
trim_segments;

typedef struct nurbs_trim_str
{
   trim_list *trim_loop;
   trim_segments *segments;
   struct nurbs_trim_str *next;
}
nurbs_trim;

typedef struct
{
   GLfloat model[16], proj[16], viewport[4];
}
culling_and_sampling_str;

struct GLUnurbs
{
   GLboolean culling;
   GLenum error;
   void (GLCALLBACK * error_callback) (GLenum err);
   GLenum display_mode;
   GLU_nurbs_enum nurbs_type;
   GLboolean auto_load_matrix;
     culling_and_sampling_str sampling_matrices;
   GLenum sampling_method;
   GLfloat sampling_tolerance;
   GLfloat parametric_tolerance;
   GLint u_step, v_step;
   nurbs_surface surface;
   nurbs_curve curve;
   nurbs_trim *trim;
};

typedef struct
{
   GLfloat *knot;
   GLint nknots;
   GLfloat *unified_knot;
   GLint unified_nknots;
   GLint order;
   GLint t_min, t_max;
   GLint delta_nknots;
   GLboolean open_at_begin, open_at_end;
   GLfloat *new_knot;
   GLfloat *alpha;
}
knot_str_type;

typedef struct
{
   GLfloat *geom_ctrl;
   GLint geom_s_stride, geom_t_stride;
   GLfloat **geom_offsets;
   GLint geom_s_pt_cnt, geom_t_pt_cnt;
   GLfloat *color_ctrl;
   GLint color_s_stride, color_t_stride;
   GLfloat **color_offsets;
   GLint color_s_pt_cnt, color_t_pt_cnt;
   GLfloat *normal_ctrl;
   GLint normal_s_stride, normal_t_stride;
   GLfloat **normal_offsets;
   GLint normal_s_pt_cnt, normal_t_pt_cnt;
   GLfloat *texture_ctrl;
   GLint texture_s_stride, texture_t_stride;
   GLfloat **texture_offsets;
   GLint texture_s_pt_cnt, texture_t_pt_cnt;
   GLint s_bezier_cnt, t_bezier_cnt;
}
new_ctrl_type;

extern void call_user_error(GLUnurbsObj * nobj, GLenum error);

extern GLenum test_knot(GLint nknots, GLfloat * knot, GLint order);

extern GLenum explode_knot(knot_str_type * the_knot);

extern GLenum calc_alphas(knot_str_type * the_knot);

extern GLenum calc_new_ctrl_pts(GLfloat * ctrl, GLint stride,
				knot_str_type * the_knot, GLint dim,
				GLfloat ** new_ctrl, GLint * ncontrol);

extern GLenum glu_do_sampling_crv(GLUnurbsObj * nobj, GLfloat * new_ctrl,
				  GLint n_ctrl, GLint order, GLint dim,
				  GLint ** factors);

extern GLenum glu_do_sampling_3D(GLUnurbsObj * nobj, new_ctrl_type * new_ctrl,
				 int **sfactors, GLint ** tfactors);

extern GLenum glu_do_sampling_uv(GLUnurbsObj * nobj, new_ctrl_type * new_ctrl,
				 int **sfactors, GLint ** tfactors);

extern GLenum glu_do_sampling_param_3D(GLUnurbsObj * nobj,
				       new_ctrl_type * new_ctrl,
				       int **sfactors, GLint ** tfactors);

extern GLboolean fine_culling_test_2D(GLUnurbsObj * nobj, GLfloat * ctrl,
				      GLint n_ctrl, GLint stride, GLint dim);

extern GLboolean fine_culling_test_3D(GLUnurbsObj * nobj, GLfloat * ctrl,
				      GLint s_n_ctrl, GLint t_n_ctrl,
				      GLint s_stride, GLint t_stride,
				      GLint dim);

extern void do_nurbs_curve(GLUnurbsObj * nobj);

extern void do_nurbs_surface(GLUnurbsObj * nobj);

extern GLenum patch_trimming(GLUnurbsObj * nobj, new_ctrl_type * new_ctrl,
			     GLint * sfactors, GLint * tfactors);

extern void collect_unified_knot(knot_str_type * dest, knot_str_type * src,
				 GLfloat maximal_min_knot,
				 GLfloat minimal_max_knot);

extern GLenum select_knot_working_range(GLUnurbsObj * nobj,
					knot_str_type * geom_knot,
					knot_str_type * color_knot,
					knot_str_type * normal_knot,
					knot_str_type * texture_knot);

extern void free_unified_knots(knot_str_type * geom_knot,
			       knot_str_type * color_knot,
			       knot_str_type * normal_knot,
			       knot_str_type * texture_knot);



#endif