/*
 Copyright (C) Intel Corp.  2006.  All Rights Reserved.
 Intel funded Tungsten Graphics to
 develop this 3D driver.

 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
 "Software"), to deal in the Software without restriction, including
 without limitation the rights to use, copy, modify, merge, publish,
 distribute, sublicense, and/or sell copies of the Software, and to
 permit persons to whom the Software is furnished to do so, subject to
 the following conditions:

 The above copyright notice and this permission notice (including the
 next paragraph) shall be included in all copies or substantial
 portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 **********************************************************************/
 /*
  * Authors:
  *   Keith Whitwell <keithw@vmware.com>
  */

#ifndef ELK_CLIP_H
#define ELK_CLIP_H

#include "elk_compiler.h"
#include "elk_eu.h"

/* Initial 3 verts, plus at most 6 additional verts from intersections
 * with fixed planes, plus at most 8 additional verts from intersections
 * with user clip planes
 */
#define MAX_VERTS (3+6+8)

#define PRIM_MASK  (0x1f)

struct elk_clip_compile {
   struct elk_codegen func;
   struct elk_clip_prog_key key;
   struct elk_clip_prog_data prog_data;

   struct {
      struct elk_reg R0;
      struct elk_reg vertex[MAX_VERTS];

      struct elk_reg t;
      struct elk_reg t0, t1;
      struct elk_reg dp0, dp1;

      struct elk_reg dpPrev;
      struct elk_reg dp;
      struct elk_reg loopcount;
      struct elk_reg nr_verts;
      struct elk_reg planemask;

      struct elk_reg inlist;
      struct elk_reg outlist;
      struct elk_reg freelist;

      struct elk_reg dir;
      struct elk_reg tmp0, tmp1;
      struct elk_reg offset;

      struct elk_reg fixed_planes;
      struct elk_reg plane_equation;

      struct elk_reg ff_sync;

      /* Bitmask indicating which coordinate attribute should be used for
       * comparison to each clipping plane. A 0 indicates that VARYING_SLOT_POS
       * should be used, because it's one of the fixed +/- x/y/z planes that
       * constitute the bounds of the view volume. A 1 indicates that
       * VARYING_SLOT_CLIP_VERTEX should be used (if available) since it's a user-
       * defined clipping plane.
       */
      struct elk_reg vertex_src_mask;

      /* Offset into the vertex of the current plane's clipdistance value */
      struct elk_reg clipdistance_offset;
   } reg;

   /* Number of registers storing VUE data */
   GLuint nr_regs;

   GLuint first_tmp;
   GLuint last_tmp;

   bool need_direction;

   struct intel_vue_map vue_map;
};

/**
 * True if the given varying is one of the outputs of the vertex shader.
 */
static inline bool elk_clip_have_varying(struct elk_clip_compile *c,
                                         GLuint varying)
{
   return (c->key.attrs & BITFIELD64_BIT(varying)) ? 1 : 0;
}

/* Points are only culled, so no need for a clip routine, however it
 * works out easier to have a dummy one.
 */
void elk_emit_unfilled_clip( struct elk_clip_compile *c );
void elk_emit_tri_clip( struct elk_clip_compile *c );
void elk_emit_line_clip( struct elk_clip_compile *c );
void elk_emit_point_clip( struct elk_clip_compile *c );

/* elk_clip_tri.c, for use by the unfilled clip routine:
 */
void elk_clip_tri_init_vertices( struct elk_clip_compile *c );
void elk_clip_tri_flat_shade( struct elk_clip_compile *c );
void elk_clip_tri( struct elk_clip_compile *c );
void elk_clip_tri_emit_polygon( struct elk_clip_compile *c );
void elk_clip_tri_alloc_regs( struct elk_clip_compile *c,
			      GLuint nr_verts );


/* Utils:
 */

void elk_clip_interp_vertex( struct elk_clip_compile *c,
			     struct elk_indirect dest_ptr,
			     struct elk_indirect v0_ptr, /* from */
			     struct elk_indirect v1_ptr, /* to */
			     struct elk_reg t0,
			     bool force_edgeflag );

void elk_clip_init_planes( struct elk_clip_compile *c );

void elk_clip_emit_vue(struct elk_clip_compile *c,
		       struct elk_indirect vert,
                       enum elk_urb_write_flags flags,
		       GLuint header);

void elk_clip_kill_thread(struct elk_clip_compile *c);

struct elk_reg elk_clip_plane_stride( struct elk_clip_compile *c );
struct elk_reg elk_clip_plane0_address( struct elk_clip_compile *c );

void elk_clip_copy_flatshaded_attributes( struct elk_clip_compile *c,
                                          GLuint to, GLuint from );

void elk_clip_init_clipmask( struct elk_clip_compile *c );

struct elk_reg get_tmp( struct elk_clip_compile *c );

void elk_clip_project_position(struct elk_clip_compile *c,
             struct elk_reg pos );
void elk_clip_ff_sync(struct elk_clip_compile *c);
void elk_clip_init_ff_sync(struct elk_clip_compile *c);

#endif