static void
lower_sampler(nir_tex_instr *instr, const struct gl_shader_program *shader_program,
gl_shader_stage stage, nir_builder *builder)
{
if (instr->sampler == NULL)
return;
instr->sampler_index = 0;
unsigned location = instr->sampler->var->data.location;
unsigned array_elements = 1;
nir_ssa_def *indirect = NULL;
builder->cursor = nir_before_instr(&instr->instr);
calc_sampler_offsets(&instr->sampler->deref, instr, &array_elements,
&indirect, builder, &location);
if (indirect) {
/* First, we have to resize the array of texture sources */
nir_tex_src *new_srcs = rzalloc_array(instr, nir_tex_src,
instr->num_srcs + 1);
for (unsigned i = 0; i < instr->num_srcs; i++) {
new_srcs[i].src_type = instr->src[i].src_type;
nir_instr_move_src(&instr->instr, &new_srcs[i].src,
&instr->src[i].src);
}
ralloc_free(instr->src);
instr->src = new_srcs;
/* Now we can go ahead and move the source over to being a
* first-class texture source.
*/
instr->src[instr->num_srcs].src_type = nir_tex_src_sampler_offset;
instr->num_srcs++;
nir_instr_rewrite_src(&instr->instr,
&instr->src[instr->num_srcs - 1].src,
nir_src_for_ssa(indirect));
instr->sampler_array_size = array_elements;
}
if (location > shader_program->NumUniformStorage - 1 ||
!shader_program->UniformStorage[location].opaque[stage].active) {
assert(!"cannot return a sampler");
return;
}
instr->sampler_index +=
shader_program->UniformStorage[location].opaque[stage].index;
instr->sampler = NULL;
}
static void
project_src(nir_builder *b, nir_tex_instr *tex)
{
/* Find the projector in the srcs list, if present. */
unsigned proj_index;
for (proj_index = 0; proj_index < tex->num_srcs; proj_index++) {
if (tex->src[proj_index].src_type == nir_tex_src_projector)
break;
}
if (proj_index == tex->num_srcs)
return;
b->cursor = nir_before_instr(&tex->instr);
nir_ssa_def *inv_proj =
nir_frcp(b, nir_ssa_for_src(b, tex->src[proj_index].src, 1));
/* Walk through the sources projecting the arguments. */
for (unsigned i = 0; i < tex->num_srcs; i++) {
switch (tex->src[i].src_type) {
case nir_tex_src_coord:
case nir_tex_src_comparitor:
break;
default:
continue;
}
nir_ssa_def *unprojected =
nir_ssa_for_src(b, tex->src[i].src, nir_tex_instr_src_size(tex, i));
nir_ssa_def *projected = nir_fmul(b, unprojected, inv_proj);
/* Array indices don't get projected, so make an new vector with the
* coordinate's array index untouched.
*/
if (tex->is_array && tex->src[i].src_type == nir_tex_src_coord) {
switch (tex->coord_components) {
case 4:
projected = nir_vec4(b,
nir_channel(b, projected, 0),
nir_channel(b, projected, 1),
nir_channel(b, projected, 2),
nir_channel(b, unprojected, 3));
break;
case 3:
projected = nir_vec3(b,
nir_channel(b, projected, 0),
nir_channel(b, projected, 1),
nir_channel(b, unprojected, 2));
break;
case 2:
projected = nir_vec2(b,
nir_channel(b, projected, 0),
nir_channel(b, unprojected, 1));
break;
default:
unreachable("bad texture coord count for array");
break;
}
}
nir_instr_rewrite_src(&tex->instr,
&tex->src[i].src,
nir_src_for_ssa(projected));
}
/* Now move the later tex sources down the array so that the projector
* disappears.
*/
nir_instr_rewrite_src(&tex->instr, &tex->src[proj_index].src,
NIR_SRC_INIT);
for (unsigned i = proj_index + 1; i < tex->num_srcs; i++) {
tex->src[i-1].src_type = tex->src[i].src_type;
nir_instr_move_src(&tex->instr, &tex->src[i-1].src, &tex->src[i].src);
}
tex->num_srcs--;
}
