1/*
2 * Copyright © 2016 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#include "main/mipmap.h"
25#include "main/teximage.h"
26#include "brw_blorp.h"
27#include "brw_context.h"
28#include "brw_tex.h"
29#include "drivers/common/meta.h"
30
31#define FILE_DEBUG_FLAG DEBUG_BLORP
32
33
34/**
35 * The GenerateMipmap() driver hook.
36 */
37void
38brw_generate_mipmap(struct gl_context *ctx, GLenum target,
39                    struct gl_texture_object *tex_obj)
40{
41   struct brw_context *brw = brw_context(ctx);
42   struct intel_device_info *devinfo = &brw->screen->devinfo;
43   struct brw_texture_object *intel_obj = brw_texture_object(tex_obj);
44   const unsigned base_level = tex_obj->Attrib.BaseLevel;
45   unsigned last_level, first_layer, last_layer;
46
47   /* Blorp doesn't handle combined depth/stencil surfaces on Gfx4-5 yet. */
48   if (devinfo->ver <= 5 &&
49       (tex_obj->Image[0][base_level]->_BaseFormat == GL_DEPTH_COMPONENT ||
50        tex_obj->Image[0][base_level]->_BaseFormat == GL_DEPTH_STENCIL)) {
51      _mesa_meta_GenerateMipmap(ctx, target, tex_obj);
52      return;
53   }
54
55   /* find expected last mipmap level to generate */
56   last_level = _mesa_compute_num_levels(ctx, tex_obj, target) - 1;
57
58   if (last_level == 0)
59      return;
60
61   /* The texture isn't in a "complete" state yet so set the expected
62    * last_level here; we're not going through normal texture validation.
63    */
64   intel_obj->_MaxLevel = last_level;
65
66   if (!tex_obj->Immutable) {
67      _mesa_prepare_mipmap_levels(ctx, tex_obj, base_level, last_level);
68
69      /* At this point, memory for all the texture levels has been
70       * allocated.  However, the base level image may be in one resource
71       * while the subsequent/smaller levels may be in another resource.
72       * Finalizing the texture will copy the base images from the former
73       * resource to the latter.
74       *
75       * After this, we'll have all mipmap levels in one resource.
76       */
77      brw_finalize_mipmap_tree(brw, tex_obj);
78   }
79
80   struct brw_mipmap_tree *mt = intel_obj->mt;
81   if (!mt) {
82      _mesa_error(ctx, GL_OUT_OF_MEMORY, "mipmap generation");
83      return;
84   }
85
86   const mesa_format format = intel_obj->_Format;
87
88   /* Fall back to the CPU for non-renderable cases.
89    *
90    * TODO: 3D textures require blending data from multiple slices,
91    * which means we need custom shaders.  For now, fall back.
92    */
93   if (!brw->mesa_format_supports_render[format] || target == GL_TEXTURE_3D) {
94      _mesa_generate_mipmap(ctx, target, tex_obj);
95      return;
96   }
97
98   const struct isl_extent4d *base_size = &mt->surf.logical_level0_px;
99
100   if (mt->target == GL_TEXTURE_CUBE_MAP) {
101      first_layer = _mesa_tex_target_to_face(target);
102      last_layer = first_layer;
103   } else {
104      first_layer = 0;
105      last_layer = base_size->array_len - 1;
106   }
107
108   /* The GL_EXT_texture_sRGB_decode extension's issues section says:
109    *
110    *    "10) How is mipmap generation of sRGB textures affected by the
111    *     TEXTURE_SRGB_DECODE_EXT parameter?
112    *
113    *     RESOLVED:  When the TEXTURE_SRGB_DECODE parameter is DECODE_EXT
114    *     for an sRGB texture, mipmap generation should decode sRGB texels
115    *     to a linear RGB color space, perform downsampling, then encode
116    *     back to an sRGB color space.  (Issue 24 in the EXT_texture_sRGB
117    *     specification provides a rationale for why.)  When the parameter
118    *     is SKIP_DECODE_EXT instead, mipmap generation skips the encode
119    *     and decode steps during mipmap generation.  By skipping the
120    *     encode and decode steps, sRGB mipmap generation should match
121    *     the mipmap generation for a non-sRGB texture."
122    */
123   bool do_srgb = tex_obj->Sampler.Attrib.sRGBDecode == GL_DECODE_EXT;
124
125   for (unsigned dst_level = base_level + 1;
126        dst_level <= last_level;
127        dst_level++) {
128
129      const unsigned src_level = dst_level - 1;
130
131      for (unsigned layer = first_layer; layer <= last_layer; layer++) {
132         brw_blorp_blit_miptrees(brw, mt, src_level, layer, format,
133                                 SWIZZLE_XYZW, mt, dst_level, layer, format,
134                                 0, 0,
135                                 minify(base_size->width, src_level),
136                                 minify(base_size->height, src_level),
137                                 0, 0,
138                                 minify(base_size->width, dst_level),
139                                 minify(base_size->height, dst_level),
140                                 GL_LINEAR, false, false,
141                                 do_srgb, do_srgb);
142      }
143   }
144}
145