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 #include "vbo/vbo_context.h"
  47
  48 #include "st_context.h"
  49 #include "st_atom.h"
  50 #include "st_draw.h"
  51 #include "st_cb_feedback.h"
  52 #include "st_cb_bufferobjects.h"
  53
  54 #include "pipe/p_context.h"
  55 #include "pipe/p_defines.h"
  56 #include "pipe/p_winsys.h"
  57 #include "pipe/cso_cache/cso_cache.h"
  58
  59 #include "pipe/draw/draw_context.h"
  60 #include "pipe/draw/draw_private.h"
  61
  62
  63 /**
  64  * This is actually used for both feedback and selection.
  65  */
  66 struct feedback_stage
  67 {
  68    struct draw_stage stage;   /**< Base class */
  69    GLcontext *ctx;            /**< Rendering context */
  70    GLboolean reset_stipple_counter;
  71 };
  72
  73
  74 /**********************************************************************
  75  * GL Feedback functions
  76  **********************************************************************/
  77
  78 static INLINE struct feedback_stage *
  79 feedback_stage( struct draw_stage *stage )
  80 {
  81    return (struct feedback_stage *)stage;
  82 }
  83
  84
  85 static void
  86 feedback_vertex(GLcontext *ctx, const struct draw_context *draw,
  87                 const struct vertex_header *v)
  88 {
  89    const struct st_context *st = ctx->st;
  90    GLfloat win[4];
  91    const GLfloat *color, *texcoord;
  92    const GLfloat ci = 0;
  93    GLuint slot;
  94
  95    /* Recall that Y=0=Top of window for Gallium wincoords */
  96    win[0] = v->data[0][0];
  97    win[1] = ctx->DrawBuffer->Height - v->data[0][1];
  98    win[2] = v->data[0][2];
  99    win[3] = 1.0F / v->data[0][3];
 100
 101    /* XXX
 102     * When we compute vertex layout, save info about position of the
 103     * color and texcoord attribs to use here.
 104     */
 105
 106    slot = st->vertex_result_to_slot[VERT_RESULT_COL0];
 107    if (slot != ~0)
 108       color = v->data[slot];
 109    else
 110       color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
 111
 112    slot = st->vertex_result_to_slot[VERT_RESULT_TEX0];
 113    if (slot != ~0)
 114       texcoord = v->data[slot];
 115    else
 116       texcoord = ctx->Current.Attrib[VERT_ATTRIB_TEX0];
 117
 118    _mesa_feedback_vertex(ctx, win, color, ci, texcoord);
 119 }
 120
 121
 122 static void
 123 feedback_tri( struct draw_stage *stage, struct prim_header *prim )
 124 {
 125    struct feedback_stage *fs = feedback_stage(stage);
 126    struct draw_context *draw = stage->draw;
 127    FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POLYGON_TOKEN);
 128    FEEDBACK_TOKEN(fs->ctx, (GLfloat) 3); /* three vertices */
 129    feedback_vertex(fs->ctx, draw, prim->v[0]);
 130    feedback_vertex(fs->ctx, draw, prim->v[1]);
 131    feedback_vertex(fs->ctx, draw, prim->v[2]);
 132 }
 133
 134
 135 static void
 136 feedback_line( struct draw_stage *stage, struct prim_header *prim )
 137 {
 138    struct feedback_stage *fs = feedback_stage(stage);
 139    struct draw_context *draw = stage->draw;
 140    if (fs->reset_stipple_counter) {
 141       FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_RESET_TOKEN);
 142       fs->reset_stipple_counter = GL_FALSE;
 143    }
 144    else {
 145       FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_TOKEN);
 146    }
 147    feedback_vertex(fs->ctx, draw, prim->v[0]);
 148    feedback_vertex(fs->ctx, draw, prim->v[1]);
 149 }
 150
 151
 152 static void
 153 feedback_point( struct draw_stage *stage, struct prim_header *prim )
 154 {
 155    struct feedback_stage *fs = feedback_stage(stage);
 156    struct draw_context *draw = stage->draw;
 157    FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POINT_TOKEN);
 158    feedback_vertex(fs->ctx, draw, prim->v[0]);
 159 }
 160
 161
 162 static void
 163 feedback_end( struct draw_stage *stage )
 164 {
 165    /* no-op */
 166 }
 167
 168
 169 static void
 170 feedback_begin( struct draw_stage *stage )
 171 {
 172    /* no-op */
 173 }
 174
 175
 176 static void
 177 feedback_reset_stipple_counter( struct draw_stage *stage )
 178 {
 179    struct feedback_stage *fs = feedback_stage(stage);
 180    fs->reset_stipple_counter = GL_TRUE;
 181 }
 182
 183
 184 /**
 185  * Create GL feedback drawing stage.
 186  */
 187 static struct draw_stage *
 188 draw_glfeedback_stage(GLcontext *ctx, struct draw_context *draw)
 189 {
 190    struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
 191
 192    fs->stage.draw = draw;
 193    fs->stage.next = NULL;
 194    fs->stage.begin = feedback_begin;
 195    fs->stage.point = feedback_point;
 196    fs->stage.line = feedback_line;
 197    fs->stage.tri = feedback_tri;
 198    fs->stage.end = feedback_end;
 199    fs->stage.reset_stipple_counter = feedback_reset_stipple_counter;
 200    fs->ctx = ctx;
 201
 202    return &fs->stage;
 203 }
 204
 205
 206
 207 /**********************************************************************
 208  * GL Selection functions
 209  **********************************************************************/
 210
 211 static void
 212 select_tri( struct draw_stage *stage, struct prim_header *prim )
 213 {
 214    struct feedback_stage *fs = feedback_stage(stage);
 215    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 216    _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
 217    _mesa_update_hitflag( fs->ctx, prim->v[2]->data[0][2] );
 218 }
 219
 220 static void
 221 select_line( struct draw_stage *stage, struct prim_header *prim )
 222 {
 223    struct feedback_stage *fs = feedback_stage(stage);
 224    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 225    _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
 226 }
 227
 228
 229 static void
 230 select_point( struct draw_stage *stage, struct prim_header *prim )
 231 {
 232    struct feedback_stage *fs = feedback_stage(stage);
 233    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 234 }
 235
 236
 237 static void
 238 select_begin( struct draw_stage *stage )
 239 {
 240    /* no-op */
 241 }
 242
 243
 244 static void
 245 select_end( struct draw_stage *stage )
 246 {
 247    /* no-op */
 248 }
 249
 250
 251 static void
 252 select_reset_stipple_counter( struct draw_stage *stage )
 253 {
 254    /* no-op */
 255 }
 256
 257
 258 /**
 259  * Create GL selection mode drawing stage.
 260  */
 261 static struct draw_stage *
 262 draw_glselect_stage(GLcontext *ctx, struct draw_context *draw)
 263 {
 264    struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
 265
 266    fs->stage.draw = draw;
 267    fs->stage.next = NULL;
 268    fs->stage.begin = select_begin;
 269    fs->stage.point = select_point;
 270    fs->stage.line = select_line;
 271    fs->stage.tri = select_tri;
 272    fs->stage.end = select_end;
 273    fs->stage.reset_stipple_counter = select_reset_stipple_counter;
 274    fs->ctx = ctx;
 275
 276    return &fs->stage;
 277 }
 278
 279
 280 static void
 281 st_RenderMode(GLcontext *ctx, GLenum newMode )
 282 {
 283    struct st_context *st = ctx->st;
 284    struct vbo_context *vbo = (struct vbo_context *) ctx->swtnl_im;
 285    struct draw_context *draw = st->draw;
 286
 287    if (newMode == GL_RENDER) {
 288       /* restore normal VBO draw function */
 289       vbo->draw_prims = st_draw_vbo;
 290    }
 291    else if (newMode == GL_SELECT) {
 292       if (!st->selection_stage)
 293          st->selection_stage = draw_glselect_stage(ctx, draw);
 294       draw_set_rasterize_stage(draw, st->selection_stage);
 295       /* Plug in new vbo draw function */
 296       vbo->draw_prims = st_feedback_draw_vbo;
 297    }
 298    else {
 299       if (!st->feedback_stage)
 300          st->feedback_stage = draw_glfeedback_stage(ctx, draw);
 301       draw_set_rasterize_stage(draw, st->feedback_stage);
 302       /* Plug in new vbo draw function */
 303       vbo->draw_prims = st_feedback_draw_vbo;
 304       /* need to generate/use a vertex program that emits pos/color/tex */
 305       st->dirty.st |= ST_NEW_VERTEX_PROGRAM;
 306    }
 307 }
 308
 309
 310
 311 void st_init_feedback_functions(struct dd_function_table *functions)
 312 {
 313    functions->RenderMode = st_RenderMode;
 314 }