src/mesa/state_tracker/st_atom_clip.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   * Authors:
  30   *   Keith Whitwell <keith@tungstengraphics.com>
  31   */
  32
  33
  34 #include "st_context.h"
  35 #include "pipe/p_context.h"
  36 #include "st_atom.h"
  37 #include "st_program.h"
  38 #include "util/u_debug.h"
  39 #include "cso_cache/cso_context.h"
  40
  41
  42 /* Second state atom for user clip planes:
  43  */
  44 static void update_clip( struct st_context *st )
  45 {
  46    struct pipe_clip_state clip;
  47    const struct gl_context *ctx = st->ctx;
  48    bool use_eye = FALSE;
  49
  50    STATIC_ASSERT(sizeof(clip.ucp) <= sizeof(ctx->Transform._ClipUserPlane));
  51
  52    /* if we have a vertex shader that writes clip vertex we need to pass
  53       the pre-projection transformed coordinates into the driver. */
  54    if (st->vp) {
  55       if (ctx->Shader.CurrentVertexProgram)
  56          use_eye = TRUE;
  57    }
  58
  59    memcpy(clip.ucp,
  60           use_eye ? ctx->Transform.EyeUserPlane
  61                   : ctx->Transform._ClipUserPlane, sizeof(clip.ucp));
  62    st->state.clip = clip;
  63    cso_set_clip(st->cso_context, &clip);
  64 }
  65
  66
  67 const struct st_tracked_state st_update_clip = {
  68    "st_update_clip",                                    /* name */
  69    {                                                    /* dirty */
  70       _NEW_TRANSFORM,                                   /* mesa */
  71       ST_NEW_VERTEX_PROGRAM,                            /* st */
  72    },
  73    update_clip                                          /* update */
  74 };