src/mesa/drivers/dri/i965/brw_primitive_restart.c

   1 /*
   2  * Copyright © 2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Jordan Justen <jordan.l.justen@intel.com>
  25  *
  26  */
  27
  28 #include "main/imports.h"
  29 #include "main/bufferobj.h"
  30
  31 #include "brw_context.h"
  32 #include "brw_draw.h"
  33
  34 /**
  35  * Check if primitive restart is enabled, and if so, handle it properly.
  36  *
  37  * In some cases the support will be handled in software. When available
  38  * hardware will handle primitive restart.
  39  */
  40 GLboolean
  41 brw_handle_primitive_restart(struct gl_context *ctx,
  42                              const struct _mesa_prim *prim,
  43                              GLuint nr_prims,
  44                              const struct _mesa_index_buffer *ib)
  45 {
  46    struct brw_context *brw = brw_context(ctx);
  47
  48    /* We only need to handle cases where there is an index buffer. */
  49    if (ib == NULL) {
  50       return GL_FALSE;
  51    }
  52
  53    /* If the driver has requested software handling of primitive restarts,
  54     * then the VBO module has already taken care of things, and we can
  55     * just draw as normal.
  56     */
  57    if (ctx->Const.PrimitiveRestartInSoftware) {
  58       return GL_FALSE;
  59    }
  60
  61    /* If we have set the in_progress flag, then we are in the middle
  62     * of handling the primitive restart draw.
  63     */
  64    if (brw->prim_restart.in_progress) {
  65       return GL_FALSE;
  66    }
  67
  68    /* If PrimitiveRestart is not enabled, then we aren't concerned about
  69     * handling this draw.
  70     */
  71    if (!(ctx->Array.PrimitiveRestart)) {
  72       return GL_FALSE;
  73    }
  74
  75    /* Signal that we are in the process of handling the
  76     * primitive restart draw
  77     */
  78    brw->prim_restart.in_progress = true;
  79
  80    vbo_sw_primitive_restart(ctx, prim, nr_prims, ib);
  81
  82    brw->prim_restart.in_progress = false;
  83
  84    /* The primitive restart draw was completed, so return true. */
  85    return GL_TRUE;
  86 }
  87