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