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 #include "vf/vf.h"
  59
  60 #include "pipe/draw/draw_context.h"
  61 #include "pipe/draw/draw_private.h"
  62
  63
  64 /**
  65  * This is actually used for both feedback and selection.
  66  */
  67 struct feedback_stage
  68 {
  69    struct draw_stage stage;   /**< Base class */
  70    GLcontext *ctx;            /**< Rendering context */
  71    GLboolean reset_stipple_counter;
  72 };
  73
  74
  75 /**********************************************************************
  76  * GL Feedback functions
  77  **********************************************************************/
  78
  79 static INLINE struct feedback_stage *
  80 feedback_stage( struct draw_stage *stage )
  81 {
  82    return (struct feedback_stage *)stage;
  83 }
  84
  85
  86 static void
  87 feedback_vertex(GLcontext *ctx, const struct draw_context *draw,
  88                 const struct vertex_header *v)
  89 {
  90    const struct st_context *st = ctx->st;
  91    GLfloat win[4];
  92    const GLfloat *color, *texcoord;
  93    const GLfloat ci = 0;
  94    GLuint slot;
  95
  96    /* Recall that Y=0=Top of window for Gallium wincoords */
  97    win[0] = v->data[0][0];
  98    win[1] = ctx->DrawBuffer->Height - v->data[0][1];
  99    win[2] = v->data[0][2];
 100    win[3] = 1.0F / v->data[0][3];
 101
 102    /* XXX
 103     * When we compute vertex layout, save info about position of the
 104     * color and texcoord attribs to use here.
 105     */
 106
 107    slot = st->vertex_result_to_slot[VERT_RESULT_COL0];
 108    if (slot != ~0)
 109       color = v->data[slot];
 110    else
 111       color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
 112
 113    slot = st->vertex_result_to_slot[VERT_RESULT_TEX0];
 114    if (slot != ~0)
 115       texcoord = v->data[slot];
 116    else
 117       texcoord = ctx->Current.Attrib[VERT_ATTRIB_TEX0];
 118
 119    _mesa_feedback_vertex(ctx, win, color, ci, texcoord);
 120 }
 121
 122
 123 static void
 124 feedback_tri( struct draw_stage *stage, struct prim_header *prim )
 125 {
 126    struct feedback_stage *fs = feedback_stage(stage);
 127    struct draw_context *draw = stage->draw;
 128    FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POLYGON_TOKEN);
 129    FEEDBACK_TOKEN(fs->ctx, (GLfloat) 3); /* three vertices */
 130    feedback_vertex(fs->ctx, draw, prim->v[0]);
 131    feedback_vertex(fs->ctx, draw, prim->v[1]);
 132    feedback_vertex(fs->ctx, draw, prim->v[2]);
 133 }
 134
 135
 136 static void
 137 feedback_line( struct draw_stage *stage, struct prim_header *prim )
 138 {
 139    struct feedback_stage *fs = feedback_stage(stage);
 140    struct draw_context *draw = stage->draw;
 141    if (fs->reset_stipple_counter) {
 142       FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_RESET_TOKEN);
 143       fs->reset_stipple_counter = GL_FALSE;
 144    }
 145    else {
 146       FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_TOKEN);
 147    }
 148    feedback_vertex(fs->ctx, draw, prim->v[0]);
 149    feedback_vertex(fs->ctx, draw, prim->v[1]);
 150 }
 151
 152
 153 static void
 154 feedback_point( struct draw_stage *stage, struct prim_header *prim )
 155 {
 156    struct feedback_stage *fs = feedback_stage(stage);
 157    struct draw_context *draw = stage->draw;
 158    FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POINT_TOKEN);
 159    feedback_vertex(fs->ctx, draw, prim->v[0]);
 160 }
 161
 162
 163 static void
 164 feedback_end( struct draw_stage *stage )
 165 {
 166    /* no-op */
 167 }
 168
 169
 170 static void
 171 feedback_begin( struct draw_stage *stage )
 172 {
 173    /* no-op */
 174 }
 175
 176
 177 static void
 178 feedback_reset_stipple_counter( struct draw_stage *stage )
 179 {
 180    struct feedback_stage *fs = feedback_stage(stage);
 181    fs->reset_stipple_counter = GL_TRUE;
 182 }
 183
 184
 185 /**
 186  * Create GL feedback drawing stage.
 187  */
 188 static struct draw_stage *
 189 draw_glfeedback_stage(GLcontext *ctx, struct draw_context *draw)
 190 {
 191    struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
 192
 193    fs->stage.draw = draw;
 194    fs->stage.next = NULL;
 195    fs->stage.begin = feedback_begin;
 196    fs->stage.point = feedback_point;
 197    fs->stage.line = feedback_line;
 198    fs->stage.tri = feedback_tri;
 199    fs->stage.end = feedback_end;
 200    fs->stage.reset_stipple_counter = feedback_reset_stipple_counter;
 201    fs->ctx = ctx;
 202
 203    return &fs->stage;
 204 }
 205
 206
 207
 208 /**********************************************************************
 209  * GL Selection functions
 210  **********************************************************************/
 211
 212 static void
 213 select_tri( struct draw_stage *stage, struct prim_header *prim )
 214 {
 215    struct feedback_stage *fs = feedback_stage(stage);
 216    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 217    _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
 218    _mesa_update_hitflag( fs->ctx, prim->v[2]->data[0][2] );
 219 }
 220
 221 static void
 222 select_line( struct draw_stage *stage, struct prim_header *prim )
 223 {
 224    struct feedback_stage *fs = feedback_stage(stage);
 225    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 226    _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
 227 }
 228
 229
 230 static void
 231 select_point( struct draw_stage *stage, struct prim_header *prim )
 232 {
 233    struct feedback_stage *fs = feedback_stage(stage);
 234    _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
 235 }
 236
 237
 238 static void
 239 select_begin( struct draw_stage *stage )
 240 {
 241    /* no-op */
 242 }
 243
 244
 245 static void
 246 select_end( struct draw_stage *stage )
 247 {
 248    /* no-op */
 249 }
 250
 251
 252 static void
 253 select_reset_stipple_counter( struct draw_stage *stage )
 254 {
 255    /* no-op */
 256 }
 257
 258
 259 /**
 260  * Create GL selection mode drawing stage.
 261  */
 262 static struct draw_stage *
 263 draw_glselect_stage(GLcontext *ctx, struct draw_context *draw)
 264 {
 265    struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
 266
 267    fs->stage.draw = draw;
 268    fs->stage.next = NULL;
 269    fs->stage.begin = select_begin;
 270    fs->stage.point = select_point;
 271    fs->stage.line = select_line;
 272    fs->stage.tri = select_tri;
 273    fs->stage.end = select_end;
 274    fs->stage.reset_stipple_counter = select_reset_stipple_counter;
 275    fs->ctx = ctx;
 276
 277    return &fs->stage;
 278 }
 279
 280
 281 static void
 282 st_RenderMode(GLcontext *ctx, GLenum newMode )
 283 {
 284    struct st_context *st = ctx->st;
 285    struct vbo_context *vbo = (struct vbo_context *) ctx->swtnl_im;
 286    struct draw_context *draw = st->draw;
 287
 288    if (newMode == GL_RENDER) {
 289       /* restore normal VBO draw function */
 290       vbo->draw_prims = st_draw_vbo;
 291    }
 292    else if (newMode == GL_SELECT) {
 293       if (!st->selection_stage)
 294          st->selection_stage = draw_glselect_stage(ctx, draw);
 295       draw_set_rasterize_stage(draw, st->selection_stage);
 296       /* Plug in new vbo draw function */
 297       vbo->draw_prims = st_feedback_draw_vbo;
 298    }
 299    else {
 300       if (!st->feedback_stage)
 301          st->feedback_stage = draw_glfeedback_stage(ctx, draw);
 302       draw_set_rasterize_stage(draw, st->feedback_stage);
 303       /* Plug in new vbo draw function */
 304       vbo->draw_prims = st_feedback_draw_vbo;
 305       /* need to generate/use a vertex program that emits pos/color/tex */
 306       st->dirty.st |= ST_NEW_VERTEX_PROGRAM;
 307    }
 308 }
 309
 310
 311
 312 void st_init_feedback_functions(struct dd_function_table *functions)
 313 {
 314    functions->RenderMode = st_RenderMode;
 315 }