From: Rob Clark Date: Tue, 22 Dec 2015 02:54:00 +0000 (-0500) Subject: nir: add lowering pass for glBitmap X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=3a939d034e41755b46b51fbe9071f5d31cdf1f81;p=mesa.git nir: add lowering pass for glBitmap Signed-off-by: Rob Clark Reviewed-by: Connor Abbott Reviewed-by: Eric Anholt --- diff --git a/src/compiler/Makefile.sources b/src/compiler/Makefile.sources index 9512207b327..903e882c1e7 100644 --- a/src/compiler/Makefile.sources +++ b/src/compiler/Makefile.sources @@ -186,6 +186,7 @@ NIR_FILES = \ nir/nir_liveness.c \ nir/nir_lower_alu_to_scalar.c \ nir/nir_lower_atomics.c \ + nir/nir_lower_bitmap.c \ nir/nir_lower_clamp_color_outputs.c \ nir/nir_lower_clip.c \ nir/nir_lower_double_ops.c \ diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h index 364972d046b..4075a5f0fc2 100644 --- a/src/compiler/nir/nir.h +++ b/src/compiler/nir/nir.h @@ -2398,6 +2398,13 @@ typedef struct nir_lower_drawpixels_options { void nir_lower_drawpixels(nir_shader *shader, const nir_lower_drawpixels_options *options); +typedef struct nir_lower_bitmap_options { + unsigned sampler; + bool swizzle_xxxx; +} nir_lower_bitmap_options; + +void nir_lower_bitmap(nir_shader *shader, const nir_lower_bitmap_options *options); + void nir_lower_atomics(nir_shader *shader, const struct gl_shader_program *shader_program); void nir_lower_to_source_mods(nir_shader *shader); diff --git a/src/compiler/nir/nir_lower_bitmap.c b/src/compiler/nir/nir_lower_bitmap.c new file mode 100644 index 00000000000..e182579a398 --- /dev/null +++ b/src/compiler/nir/nir_lower_bitmap.c @@ -0,0 +1,139 @@ +/* + * Copyright © 2015 Red Hat + * + * 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. + */ + +#include "nir.h" +#include "nir_builder.h" + +/* Lower glBitmap(). + * + * This is based on the logic in st_get_bitmap_shader() in TGSI compiler. + * From st_cb_bitmap.c: + * + * glBitmaps are drawn as textured quads. The user's bitmap pattern + * is stored in a texture image. An alpha8 texture format is used. + * The fragment shader samples a bit (texel) from the texture, then + * discards the fragment if the bit is off. + * + * Note that we actually store the inverse image of the bitmap to + * simplify the fragment program. An "on" bit gets stored as texel=0x0 + * and an "off" bit is stored as texel=0xff. Then we kill the + * fragment if the negated texel value is less than zero. + * + * Note that the texture format will be, according to what driver supports, + * in order of preference (with swizzle): + * + * I8_UNORM - .xxxx + * A8_UNORM - .000x + * L8_UNORM - .xxx1 + * + * If L8_UNORM, options->swizzle_xxxx is true. Otherwise we can just use + * the .w comp. + * + * Run before nir_lower_io. + */ + +static nir_variable * +get_texcoord(nir_shader *shader) +{ + nir_variable *texcoord = NULL; + + /* find gl_TexCoord, if it exists: */ + nir_foreach_variable(var, &shader->inputs) { + if (var->data.location == VARYING_SLOT_TEX0) { + texcoord = var; + break; + } + } + + /* otherwise create it: */ + if (texcoord == NULL) { + texcoord = nir_variable_create(shader, + nir_var_shader_in, + glsl_vec4_type(), + "gl_TexCoord"); + texcoord->data.location = VARYING_SLOT_TEX0; + } + + return texcoord; +} + +static void +lower_bitmap(nir_shader *shader, nir_builder *b, + const nir_lower_bitmap_options *options) +{ + nir_ssa_def *texcoord; + nir_tex_instr *tex; + nir_ssa_def *cond; + nir_intrinsic_instr *discard; + + texcoord = nir_load_var(b, get_texcoord(shader)); + + tex = nir_tex_instr_create(shader, 1); + tex->op = nir_texop_tex; + tex->sampler_dim = GLSL_SAMPLER_DIM_2D; + tex->coord_components = 2; + tex->sampler_index = options->sampler; + tex->texture_index = options->sampler; + tex->dest_type = nir_type_float; + tex->src[0].src = nir_src_for_ssa(texcoord); + + nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL); + nir_builder_instr_insert(b, &tex->instr); + + /* kill if tex != 0.0.. take .x or .w channel according to format: */ + cond = nir_f2b(b, nir_channel(b, &tex->dest.ssa, + options->swizzle_xxxx ? 0 : 3)); + + discard = nir_intrinsic_instr_create(shader, nir_intrinsic_discard_if); + discard->src[0] = nir_src_for_ssa(cond); + nir_builder_instr_insert(b, &discard->instr); +} + +static void +lower_bitmap_impl(nir_function_impl *impl, + const nir_lower_bitmap_options *options) +{ + nir_builder b; + + nir_builder_init(&b, impl); + b.cursor = nir_before_cf_list(&impl->body); + + lower_bitmap(impl->function->shader, &b, options); + + nir_metadata_preserve(impl, nir_metadata_block_index | + nir_metadata_dominance); +} + +void +nir_lower_bitmap(nir_shader *shader, + const nir_lower_bitmap_options *options) +{ + nir_function *function; + + assert(shader->stage == MESA_SHADER_FRAGMENT); + + function = nir_shader_get_entrypoint(shader); + + if (function->impl) + lower_bitmap_impl(function->impl, options); +}