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

   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 "intel_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  */
  37 void
  38 brw_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 gen_device_info *devinfo = &brw->screen->devinfo;
  43    struct intel_texture_object *intel_obj = intel_texture_object(tex_obj);
  44    const unsigned base_level = tex_obj->BaseLevel;
  45    unsigned last_level, first_layer, last_layer;
  46
  47    /* Blorp doesn't handle combined depth/stencil surfaces on Gen4-5 yet. */
  48    if (devinfo->gen <= 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       intel_finalize_mipmap_tree(brw, tex_obj);
  78    }
  79
  80    struct intel_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.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 }