| /* |
| * Copyright © 2015 Intel Corporation |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| * |
| * Authors: |
| * Jason Ekstrand <jason@jlekstrand.net> |
| */ |
| |
| #include "nir.h" |
| #include "nir_builder.h" |
| |
| /** |
| * This file implements a NIR lowering pass to perform the normalization of |
| * the cubemap coordinates to have the largest magnitude component be -1.0 |
| * or 1.0. This is based on the old GLSL IR based pass by Eric. |
| */ |
| |
| static bool |
| normalize_cubemap_coords_block(nir_block *block, nir_builder *b) |
| { |
| bool progress = false; |
| |
| nir_foreach_instr(instr, block) { |
| if (instr->type != nir_instr_type_tex) |
| continue; |
| |
| nir_tex_instr *tex = nir_instr_as_tex(instr); |
| if (tex->sampler_dim != GLSL_SAMPLER_DIM_CUBE) |
| continue; |
| |
| b->cursor = nir_before_instr(&tex->instr); |
| |
| for (unsigned i = 0; i < tex->num_srcs; i++) { |
| if (tex->src[i].src_type != nir_tex_src_coord) |
| continue; |
| |
| nir_ssa_def *orig_coord = |
| nir_ssa_for_src(b, tex->src[i].src, nir_tex_instr_src_size(tex, i)); |
| assert(orig_coord->num_components >= 3); |
| |
| nir_ssa_def *abs = nir_fabs(b, orig_coord); |
| nir_ssa_def *norm = nir_fmax(b, nir_channel(b, abs, 0), |
| nir_fmax(b, nir_channel(b, abs, 1), |
| nir_channel(b, abs, 2))); |
| |
| nir_ssa_def *normalized = nir_fmul(b, orig_coord, nir_frcp(b, norm)); |
| |
| /* Array indices don't have to be normalized, so make a new vector |
| * with the coordinate's array index untouched. |
| */ |
| if (tex->coord_components == 4) { |
| normalized = nir_vec4(b, |
| nir_channel(b, normalized, 0), |
| nir_channel(b, normalized, 1), |
| nir_channel(b, normalized, 2), |
| nir_channel(b, orig_coord, 3)); |
| } |
| |
| nir_instr_rewrite_src(&tex->instr, |
| &tex->src[i].src, |
| nir_src_for_ssa(normalized)); |
| |
| progress = true; |
| } |
| } |
| |
| return progress; |
| } |
| |
| static bool |
| normalize_cubemap_coords_impl(nir_function_impl *impl) |
| { |
| nir_builder b; |
| nir_builder_init(&b, impl); |
| bool progress = false; |
| |
| nir_foreach_block(block, impl) { |
| progress |= normalize_cubemap_coords_block(block, &b); |
| } |
| |
| nir_metadata_preserve(impl, nir_metadata_block_index | |
| nir_metadata_dominance); |
| |
| return progress; |
| } |
| |
| bool |
| nir_normalize_cubemap_coords(nir_shader *shader) |
| { |
| bool progress = false; |
| |
| nir_foreach_function(function, shader) { |
| if (function->impl) |
| progress = normalize_cubemap_coords_impl(function->impl) || progress; |
| } |
| |
| return progress; |
| } |