src/mesa/drivers/dri/intel/intel_resolve_map.h

   1 /*
   2  * Copyright © 2011 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
  24 #pragma once
  25
  26 #include <stdint.h>
  27
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 /**
  33  * For an overview of the HiZ operations, see the following sections of the
  34  * Sandy Bridge PRM, Volume 1, Part2:
  35  *   - 7.5.3.1 Depth Buffer Clear
  36  *   - 7.5.3.2 Depth Buffer Resolve
  37  *   - 7.5.3.3 Hierarchical Depth Buffer Resolve
  38  *
  39  * Of these, two get entered in the resolve map as needing to be done to the
  40  * buffer: depth resolve and hiz resolve.
  41  */
  42 enum gen6_hiz_op {
  43    GEN6_HIZ_OP_DEPTH_CLEAR,
  44    GEN6_HIZ_OP_DEPTH_RESOLVE,
  45    GEN6_HIZ_OP_HIZ_RESOLVE,
  46    GEN6_HIZ_OP_NONE,
  47 };
  48
  49 /**
  50  * \brief Map of miptree slices to needed resolves.
  51  *
  52  * The map is implemented as a linear doubly-linked list.
  53  *
  54  * In the intel_resolve_map*() functions, the \c head argument is not
  55  * inspected for its data. It only serves as an anchor for the list.
  56  *
  57  * \par Design Discussion
  58  *
  59  *     There are two possible ways to record which miptree slices need
  60  *     resolves. 1) Maintain a flag for every miptree slice in the texture,
  61  *     likely in intel_mipmap_level::slice, or 2) maintain a list of only
  62  *     those slices that need a resolve.
  63  *
  64  *     Immediately before drawing, a full depth resolve performed on each
  65  *     enabled depth texture. If design 1 were chosen, then at each draw call
  66  *     it would be necessary to iterate over each miptree slice of each
  67  *     enabled depth texture in order to query if each slice needed a resolve.
  68  *     In the worst case, this would require 2^16 iterations: 16 texture
  69  *     units, 16 miplevels, and 256 depth layers (assuming maximums for OpenGL
  70  *     2.1).
  71  *
  72  *     By choosing design 2, the number of iterations is exactly the minimum
  73  *     necessary.
  74  */
  75 struct intel_resolve_map {
  76    uint32_t level;
  77    uint32_t layer;
  78    enum gen6_hiz_op need;
  79
  80    struct intel_resolve_map *next;
  81    struct intel_resolve_map *prev;
  82 };
  83
  84 void
  85 intel_resolve_map_set(struct intel_resolve_map *head,
  86                       uint32_t level,
  87                       uint32_t layer,
  88                       enum gen6_hiz_op need);
  89
  90 struct intel_resolve_map*
  91 intel_resolve_map_get(struct intel_resolve_map *head,
  92                       uint32_t level,
  93                       uint32_t layer);
  94
  95 void
  96 intel_resolve_map_remove(struct intel_resolve_map *elem);
  97
  98 void
  99 intel_resolve_map_clear(struct intel_resolve_map *head);
 100
 101 #ifdef __cplusplus
 102 } /* extern "C" */
 103 #endif
 104