Home | History | Annotate | Download | only in i965
      1 /*
      2  Copyright (C) Intel Corp.  2006.  All Rights Reserved.
      3  Intel funded Tungsten Graphics 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 <keithw (at) vmware.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    bool contains_flat_varying;
     51    bool contains_noperspective_varying;
     52    const unsigned char *interp_mode;
     53    GLuint primitive:4;
     54    GLuint nr_userclip:4;
     55    GLuint pv_first:1;
     56    GLuint do_unfilled:1;
     57    GLuint fill_cw:2;		/* includes cull information */
     58    GLuint fill_ccw:2;		/* includes cull information */
     59    GLuint offset_cw:1;
     60    GLuint offset_ccw:1;
     61    GLuint copy_bfc_cw:1;
     62    GLuint copy_bfc_ccw:1;
     63    GLuint clip_mode:3;
     64 
     65    GLfloat offset_factor;
     66    GLfloat offset_units;
     67    GLfloat offset_clamp;
     68 };
     69 
     70 
     71 #define CLIP_LINE   0
     72 #define CLIP_POINT  1
     73 #define CLIP_FILL   2
     74 #define CLIP_CULL   3
     75 
     76 
     77 #define PRIM_MASK  (0x1f)
     78 
     79 struct brw_clip_compile {
     80    struct brw_codegen func;
     81    struct brw_clip_prog_key key;
     82    struct brw_clip_prog_data prog_data;
     83 
     84    struct {
     85       struct brw_reg R0;
     86       struct brw_reg vertex[MAX_VERTS];
     87 
     88       struct brw_reg t;
     89       struct brw_reg t0, t1;
     90       struct brw_reg dp0, dp1;
     91 
     92       struct brw_reg dpPrev;
     93       struct brw_reg dp;
     94       struct brw_reg loopcount;
     95       struct brw_reg nr_verts;
     96       struct brw_reg planemask;
     97 
     98       struct brw_reg inlist;
     99       struct brw_reg outlist;
    100       struct brw_reg freelist;
    101 
    102       struct brw_reg dir;
    103       struct brw_reg tmp0, tmp1;
    104       struct brw_reg offset;
    105 
    106       struct brw_reg fixed_planes;
    107       struct brw_reg plane_equation;
    108 
    109       struct brw_reg ff_sync;
    110 
    111       /* Bitmask indicating which coordinate attribute should be used for
    112        * comparison to each clipping plane. A 0 indicates that VARYING_SLOT_POS
    113        * should be used, because it's one of the fixed +/- x/y/z planes that
    114        * constitute the bounds of the view volume. A 1 indicates that
    115        * VARYING_SLOT_CLIP_VERTEX should be used (if available) since it's a user-
    116        * defined clipping plane.
    117        */
    118       struct brw_reg vertex_src_mask;
    119 
    120       /* Offset into the vertex of the current plane's clipdistance value */
    121       struct brw_reg clipdistance_offset;
    122    } reg;
    123 
    124    /* Number of registers storing VUE data */
    125    GLuint nr_regs;
    126 
    127    GLuint first_tmp;
    128    GLuint last_tmp;
    129 
    130    bool need_direction;
    131 
    132    struct brw_vue_map vue_map;
    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
    196