src/mesa/state_tracker/st_cb_feedback.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * 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, sub license, 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 portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 /**
  29  * GL_SELECT and GL_FEEDBACK render modes.
  30  * Basically, we use a private instance of the 'draw' module for doing
  31  * selection/feedback.  It would be nice to use the transform_feedback
  32  * hardware feature, but it's defined as happening pre-clip and we want
  33  * post-clipped primitives.  Also, there's concerns about the efficiency
  34  * of using the hardware for this anyway.
  35  *
  36  * Authors:
  37  *   Brian Paul
  38  */
  39
  40 #include "main/imports.h"
  41 #include "main/context.h"
  42 #include "main/feedback.h"
  43 #include "main/macros.h"
  44
  45 #include "vbo/vbo.h"
  46
  47 #include "st_context.h"
  48 #include "st_atom.h"
  49 #include "st_draw.h"
  50 #include "st_cb_feedback.h"
  51 #include "st_cb_bufferobjects.h"
  52
  53 #include "pipe/p_context.h"
  54 #include "pipe/p_defines.h"
  55 #include "pipe/p_winsys.h"
  56 #include "pipe/cso_cache/cso_cache.h"
  57
  58 #include "pipe/draw/draw_context.h"
  59 #include "pipe/draw/draw_private.h"
  60
  61
  62 /**
  63  * This is actually used for both feedback and selection.
  64  */
  65 struct feedback_stage
  66 {
  67    struct draw_stage stage;   /**< Base class */
  68    GLcontext *ctx;            /**< Rendering context */
  69    GLboolean reset_stipple_counter;
  70 };
  71
  72
  73 /**********************************************************************
  74  * GL Feedback functions
  75  **********************************************************************/
  76
  77 static INLINE struct feedback_stage *
  78 feedback_stage( struct draw_stage *stage )
  79 {
  80    return (struct feedback_stage *)stage;
  81 }
  82
  83
  84 static void
  85 feedback_vertex(GLcontext *ctx, const struct draw_context *draw,
  86                 const struct vertex_header *v)
  87 {
  88    const struct st_context *st = ctx->st;
  89    GLfloat win[4];
  90    const GLfloat *color, *texcoord;
  91    const GLfloat ci = 0;
  92    GLuint slot;
  93
  94    /* Recall that Y=0=Top of window for Gallium wincoords */
  95    win[0] = v->data[0][0];
  96    win[1] = ctx->DrawBuffer->Height - v->data[0][1];
  97    win[2] = v->data[0][2];
  98    win[3] = 1.0F / v->data[0][3];
  99
 100    /* XXX
 101     * When we compute vertex layout, save info about position of the
 102     * color and texcoord attribs to use here.
 103     */
 104
 105    slot = st->vertex_result_to_slot[VERT_RESULT_COL0];
 106    if (slot != ~0)
 107       color = v->data[slot];
 108    else
 109       color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
 110
 111    slot = st->vertex_result_to_slot[VERT_RESULT_TEX0];
 112    if (slot != ~0)
 113       texcoord = v->data[slot];
 114    else
 115       texcoord = ctx->Current.Attrib[VERT_ATTRIB_TEX0];
 116
 117    _mesa_feedback_vertex(ctx, win, color, ci, texcoord);
 118 }
 119
 120
 121 static void
 122 feedback_tri( struct draw_stage *stage, struct prim_header *prim )
 123 {
 124    struct feedback_stage *fs = feedback_stage(stage);
 125    struct draw_context *draw = stage->draw;
 126    FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POLYGON_TOKEN);
 127    FEEDBACK_TOKEN(fs->ctx, (GLfloat) 3); /* three vertices */
 128    feedback_vertex(fs->ctx, draw, prim->v[0]);
 129    feedback_vertex(fs->ctx, draw, prim->v[1]);
 130    feedback_vertex(fs->ctx, draw, prim->v[2]);
 131 }
 132
 133
 134 static void
 135 feedback_line( struct draw_stage *stage, struct prim_header *prim )
 136 {
 137    struct feedback_stage *fs = feedback_stage(stage);
 138    struct draw_context *draw = stage->draw;
 139    if (fs->reset_stipple_counter) {
 140       FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_RESET_TOKEN);
 141       fs->reset_stipple_counter = GL_FALSE;
 142    }
 143    else {
 144       FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_TOKEN);
 145    }
 146    feedback_vertex(fs->ctx, draw, prim->v[0]);
 147    feedback_vertex(fs->ctx, draw, prim->v[1]);
 148 }
 149
 150
 151 static void
 152 feedback_point( struct draw_stage *stage, struct prim_header *prim )
 153 {
 154    struct feedback_stage *fs = feedback_stage(stage);
 155    struct draw_context *draw = stage->draw;
 156    FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POINT_TOKEN);
 157    feedback_vertex(fs->ctx, draw, prim->v[0]);
 158 }
 159
 160
 161 static void
 162 feedback_end( struct draw_stage *stage )
 163 {
 164    /* no-op */
 165 }
 166
 167
 168 static void
 169 feedback_begin( struct draw_stage *stage )
 170 {
 171    /* no-op */
 172 }
 173
 174
 175 static void
 176 feedback_reset_stipple_counter( struct draw_stage *stage )
 177 {
 178    struct feedback_stage *fs = feedback_stage(stage);
 179    fs->reset_stipple_counter = GL_TRUE;
 180 }
 181
 182
 183 /**
 184  * Create GL feedback drawing stage.
 185  */
 186 static struct draw_stage *
 187 draw_glfeedback_stage(GLcontext *ctx, struct draw_context *draw)
 188 {
 189    struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
 190
 191    fs->stage.draw = draw;
 192    fs->stage.next = NULL;
 193    fs->stage.begin = feedback_begin;
 194    fs->stage.point = feedback_point;
 195    fs->stage.line = feedback_line;
 196    fs->stage.tri = feedback_tri;
 197    fs->stage.end = feedback_end;
 198    fs->stage.reset_stipple_counter = feedback_reset_stipple_counter;
 199    fs->ctx = ctx;
 200
 201    return &fs->stage;
 202 }
 203
 204
 205
 206 /**********************************************************************
 207  * GL Selection functions
 208  **********************************************************************/
 209
 210 static void
 211 select_tri( struct draw_stage *stage, struct prim_header *prim )
 212 {
 213    struct feedback_stage *fs = feedback_stage(stage);
 214    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 215    _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
 216    _mesa_update_hitflag( fs->ctx, prim->v[2]->data[0][2] );
 217 }
 218
 219 static void
 220 select_line( struct draw_stage *stage, struct prim_header *prim )
 221 {
 222    struct feedback_stage *fs = feedback_stage(stage);
 223    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 224    _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
 225 }
 226
 227
 228 static void
 229 select_point( struct draw_stage *stage, struct prim_header *prim )
 230 {
 231    struct feedback_stage *fs = feedback_stage(stage);
 232    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 233 }
 234
 235
 236 static void
 237 select_begin( struct draw_stage *stage )
 238 {
 239    /* no-op */
 240 }
 241
 242
 243 static void
 244 select_end( struct draw_stage *stage )
 245 {
 246    /* no-op */
 247 }
 248
 249
 250 static void
 251 select_reset_stipple_counter( struct draw_stage *stage )
 252 {
 253    /* no-op */
 254 }
 255
 256
 257 /**
 258  * Create GL selection mode drawing stage.
 259  */
 260 static struct draw_stage *
 261 draw_glselect_stage(GLcontext *ctx, struct draw_context *draw)
 262 {
 263    struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
 264
 265    fs->stage.draw = draw;
 266    fs->stage.next = NULL;
 267    fs->stage.begin = select_begin;
 268    fs->stage.point = select_point;
 269    fs->stage.line = select_line;
 270    fs->stage.tri = select_tri;
 271    fs->stage.end = select_end;
 272    fs->stage.reset_stipple_counter = select_reset_stipple_counter;
 273    fs->ctx = ctx;
 274
 275    return &fs->stage;
 276 }
 277
 278
 279 static void
 280 st_RenderMode(GLcontext *ctx, GLenum newMode )
 281 {
 282    struct st_context *st = ctx->st;
 283    struct draw_context *draw = st->draw;
 284
 285    if (newMode == GL_RENDER) {
 286       /* restore normal VBO draw function */
 287       vbo_set_draw_func(ctx, st_draw_vbo);
 288    }
 289    else if (newMode == GL_SELECT) {
 290       if (!st->selection_stage)
 291          st->selection_stage = draw_glselect_stage(ctx, draw);
 292       draw_set_rasterize_stage(draw, st->selection_stage);
 293       /* Plug in new vbo draw function */
 294       vbo_set_draw_func(ctx, st_feedback_draw_vbo);
 295    }
 296    else {
 297       if (!st->feedback_stage)
 298          st->feedback_stage = draw_glfeedback_stage(ctx, draw);
 299       draw_set_rasterize_stage(draw, st->feedback_stage);
 300       /* Plug in new vbo draw function */
 301       vbo_set_draw_func(ctx, st_feedback_draw_vbo);
 302       /* need to generate/use a vertex program that emits pos/color/tex */
 303       st->dirty.st |= ST_NEW_VERTEX_PROGRAM;
 304    }
 305 }
 306
 307
 308
 309 void st_init_feedback_functions(struct dd_function_table *functions)
 310 {
 311    functions->RenderMode = st_RenderMode;
 312 }