src/mesa/drivers/dri/i965/brw_clip.h

   1 /*
   2  Copyright (C) Intel Corp.  2006.  All Rights Reserved.
   3  Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
   4  develop this 3D driver.
   5
   6  Permission is hereby granted, free of charge, to any person obtaining
   7  a copy of this software and associated documentation files (the
   8  "Software"), to deal in the Software without restriction, including
   9  without limitation the rights to use, copy, modify, merge, publish,
  10  distribute, sublicense, and/or sell copies of the Software, and to
  11  permit persons to whom the Software is furnished to do so, subject to
  12  the following conditions:
  13
  14  The above copyright notice and this permission notice (including the
  15  next paragraph) shall be included in all copies or substantial
  16  portions of the Software.
  17
  18  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21  IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  22  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25
  26  **********************************************************************/
  27  /*
  28   * Authors:
  29   *   Keith Whitwell <keith@tungstengraphics.com>
  30   */
  31
  32 #ifndef BRW_CLIP_H
  33 #define BRW_CLIP_H
  34
  35
  36 #include "brw_context.h"
  37 #include "brw_eu.h"
  38
  39 /* Initial 3 verts, plus at most 6 additional verts from intersections
  40  * with fixed planes, plus at most 8 additional verts from intersections
  41  * with user clip planes
  42  */
  43 #define MAX_VERTS (3+6+8)
  44
  45 /* Note that if unfilled primitives are being emitted, we have to fix
  46  * up polygon offset and flatshading at this point:
  47  */
  48 struct brw_clip_prog_key {
  49    GLbitfield64 attrs;
  50    struct interpolation_mode_map interpolation_mode;
  51    GLuint primitive:4;
  52    GLuint nr_userclip:4;
  53    GLuint pv_first:1;
  54    GLuint do_unfilled:1;
  55    GLuint fill_cw:2;            /* includes cull information */
  56    GLuint fill_ccw:2;           /* includes cull information */
  57    GLuint offset_cw:1;
  58    GLuint offset_ccw:1;
  59    GLuint copy_bfc_cw:1;
  60    GLuint copy_bfc_ccw:1;
  61    GLuint clip_mode:3;
  62
  63    GLfloat offset_factor;
  64    GLfloat offset_units;
  65 };
  66
  67
  68 #define CLIP_LINE   0
  69 #define CLIP_POINT  1
  70 #define CLIP_FILL   2
  71 #define CLIP_CULL   3
  72
  73
  74 #define PRIM_MASK  (0x1f)
  75
  76 struct brw_clip_compile {
  77    struct brw_compile func;
  78    struct brw_clip_prog_key key;
  79    struct brw_clip_prog_data prog_data;
  80
  81    struct {
  82       struct brw_reg R0;
  83       struct brw_reg vertex[MAX_VERTS];
  84
  85       struct brw_reg t;
  86       struct brw_reg t0, t1;
  87       struct brw_reg dp0, dp1;
  88
  89       struct brw_reg dpPrev;
  90       struct brw_reg dp;
  91       struct brw_reg loopcount;
  92       struct brw_reg nr_verts;
  93       struct brw_reg planemask;
  94
  95       struct brw_reg inlist;
  96       struct brw_reg outlist;
  97       struct brw_reg freelist;
  98
  99       struct brw_reg dir;
 100       struct brw_reg tmp0, tmp1;
 101       struct brw_reg offset;
 102
 103       struct brw_reg fixed_planes;
 104       struct brw_reg plane_equation;
 105
 106       struct brw_reg ff_sync;
 107
 108       /* Bitmask indicating which coordinate attribute should be used for
 109        * comparison to each clipping plane. A 0 indicates that VARYING_SLOT_POS
 110        * should be used, because it's one of the fixed +/- x/y/z planes that
 111        * constitute the bounds of the view volume. A 1 indicates that
 112        * VARYING_SLOT_CLIP_VERTEX should be used (if available) since it's a user-
 113        * defined clipping plane.
 114        */
 115       struct brw_reg vertex_src_mask;
 116
 117       /* Offset into the vertex of the current plane's clipdistance value */
 118       struct brw_reg clipdistance_offset;
 119    } reg;
 120
 121    /* Number of registers storing VUE data */
 122    GLuint nr_regs;
 123
 124    GLuint first_tmp;
 125    GLuint last_tmp;
 126
 127    bool need_direction;
 128
 129    struct brw_vue_map vue_map;
 130
 131    bool has_flat_shading;
 132    bool has_noperspective_shading;
 133 };
 134
 135 /**
 136  * True if the given varying is one of the outputs of the vertex shader.
 137  */
 138 static inline bool brw_clip_have_varying(struct brw_clip_compile *c,
 139                                          GLuint varying)
 140 {
 141    return (c->key.attrs & BITFIELD64_BIT(varying)) ? 1 : 0;
 142 }
 143
 144 /* Points are only culled, so no need for a clip routine, however it
 145  * works out easier to have a dummy one.
 146  */
 147 void brw_emit_unfilled_clip( struct brw_clip_compile *c );
 148 void brw_emit_tri_clip( struct brw_clip_compile *c );
 149 void brw_emit_line_clip( struct brw_clip_compile *c );
 150 void brw_emit_point_clip( struct brw_clip_compile *c );
 151
 152 /* brw_clip_tri.c, for use by the unfilled clip routine:
 153  */
 154 void brw_clip_tri_init_vertices( struct brw_clip_compile *c );
 155 void brw_clip_tri_flat_shade( struct brw_clip_compile *c );
 156 void brw_clip_tri( struct brw_clip_compile *c );
 157 void brw_clip_tri_emit_polygon( struct brw_clip_compile *c );
 158 void brw_clip_tri_alloc_regs( struct brw_clip_compile *c,
 159                               GLuint nr_verts );
 160
 161
 162 /* Utils:
 163  */
 164
 165 void brw_clip_interp_vertex( struct brw_clip_compile *c,
 166                              struct brw_indirect dest_ptr,
 167                              struct brw_indirect v0_ptr, /* from */
 168                              struct brw_indirect v1_ptr, /* to */
 169                              struct brw_reg t0,
 170                              bool force_edgeflag );
 171
 172 void brw_clip_init_planes( struct brw_clip_compile *c );
 173
 174 void brw_clip_emit_vue(struct brw_clip_compile *c,
 175                        struct brw_indirect vert,
 176                        enum brw_urb_write_flags flags,
 177                        GLuint header);
 178
 179 void brw_clip_kill_thread(struct brw_clip_compile *c);
 180
 181 struct brw_reg brw_clip_plane_stride( struct brw_clip_compile *c );
 182 struct brw_reg brw_clip_plane0_address( struct brw_clip_compile *c );
 183
 184 void brw_clip_copy_flatshaded_attributes( struct brw_clip_compile *c,
 185                                           GLuint to, GLuint from );
 186
 187 void brw_clip_init_clipmask( struct brw_clip_compile *c );
 188
 189 struct brw_reg get_tmp( struct brw_clip_compile *c );
 190
 191 void brw_clip_project_position(struct brw_clip_compile *c,
 192              struct brw_reg pos );
 193 void brw_clip_ff_sync(struct brw_clip_compile *c);
 194 void brw_clip_init_ff_sync(struct brw_clip_compile *c);
 195 #endif