return write;
}
+void
+fs_visitor::emit_alpha_to_coverage_workaround(const fs_reg &src0_alpha)
+{
+ /* We need to compute alpha to coverage dithering manually in shader
+ * and replace sample mask store with the bitwise-AND of sample mask and
+ * alpha to coverage dithering.
+ *
+ * The following formula is used to compute final sample mask:
+ * m = int(16.0 * clamp(src0_alpha, 0.0, 1.0))
+ * dither_mask = 0x1111 * ((0xfea80 >> (m & ~3)) & 0xf) |
+ * 0x0808 * (m & 2) | 0x0100 * (m & 1)
+ * sample_mask = sample_mask & dither_mask
+ *
+ * It gives a number of ones proportional to the alpha for 2, 4, 8 or 16
+ * least significant bits of the result:
+ * 0.0000 0000000000000000
+ * 0.0625 0000000100000000
+ * 0.1250 0001000000010000
+ * 0.1875 0001000100010000
+ * 0.2500 1000100010001000
+ * 0.3125 1000100110001000
+ * 0.3750 1001100010011000
+ * 0.4375 1001100110011000
+ * 0.5000 1010101010101010
+ * 0.5625 1010101110101010
+ * 0.6250 1011101010111010
+ * 0.6875 1011101110111010
+ * 0.7500 1110111011101110
+ * 0.8125 1110111111101110
+ * 0.8750 1111111011111110
+ * 0.9375 1111111111111110
+ * 1.0000 1111111111111111
+ */
+ const fs_builder abld = bld.annotate("compute alpha_to_coverage & "
+ "sample_mask");
+
+ /* clamp(src0_alpha, 0.f, 1.f) */
+ const fs_reg float_tmp = abld.vgrf(BRW_REGISTER_TYPE_F);
+ set_saturate(true, abld.MOV(float_tmp, src0_alpha));
+
+ /* 16.0 * clamp(src0_alpha, 0.0, 1.0) */
+ abld.MUL(float_tmp, float_tmp, brw_imm_f(16.0));
+
+ /* m = int(16.0 * clamp(src0_alpha, 0.0, 1.0)) */
+ const fs_reg m = abld.vgrf(BRW_REGISTER_TYPE_UW);
+ abld.MOV(m, float_tmp);
+
+ /* 0x1111 * ((0xfea80 >> (m & ~3)) & 0xf) */
+ const fs_reg int_tmp_1 = abld.vgrf(BRW_REGISTER_TYPE_UW);
+ const fs_reg shift_const = abld.vgrf(BRW_REGISTER_TYPE_UD);
+ abld.MOV(shift_const, brw_imm_d(0xfea80));
+ abld.AND(int_tmp_1, m, brw_imm_uw(~3));
+ abld.SHR(int_tmp_1, shift_const, int_tmp_1);
+ abld.AND(int_tmp_1, int_tmp_1, brw_imm_uw(0xf));
+ abld.MUL(int_tmp_1, int_tmp_1, brw_imm_uw(0x1111));
+
+ /* 0x0808 * (m & 2) */
+ const fs_reg int_tmp_2 = abld.vgrf(BRW_REGISTER_TYPE_UW);
+ abld.AND(int_tmp_2, m, brw_imm_uw(2));
+ abld.MUL(int_tmp_2, int_tmp_2, brw_imm_uw(0x0808));
+
+ abld.OR(int_tmp_1, int_tmp_1, int_tmp_2);
+
+ /* 0x0100 * (m & 1) */
+ const fs_reg int_tmp_3 = abld.vgrf(BRW_REGISTER_TYPE_UW);
+ abld.AND(int_tmp_3, m, brw_imm_uw(1));
+ abld.MUL(int_tmp_3, int_tmp_3, brw_imm_uw(0x0100));
+
+ abld.OR(int_tmp_1, int_tmp_1, int_tmp_3);
+
+ /* sample_mask = sample_mask & dither_mask */
+ const fs_reg mask = abld.vgrf(BRW_REGISTER_TYPE_UD);
+ abld.AND(mask, sample_mask, int_tmp_1);
+ sample_mask = mask;
+}
+
void
fs_visitor::emit_fb_writes()
{
"in SIMD16+ mode.\n");
}
+ /* ANV doesn't know about sample mask output during the wm key creation
+ * so we compute if we need replicate alpha and emit alpha to coverage
+ * workaround here.
+ */
+ prog_data->replicate_alpha = key->alpha_test_replicate_alpha ||
+ (key->nr_color_regions > 1 && key->alpha_to_coverage &&
+ (sample_mask.file == BAD_FILE || devinfo->gen == 6));
+
+ /* From the SKL PRM, Volume 7, "Alpha Coverage":
+ * "If Pixel Shader outputs oMask, AlphaToCoverage is disabled in
+ * hardware, regardless of the state setting for this feature."
+ */
+ if (devinfo->gen > 6 && key->alpha_to_coverage &&
+ sample_mask.file != BAD_FILE && this->outputs[0].file != BAD_FILE)
+ emit_alpha_to_coverage_workaround(offset(this->outputs[0], bld, 3));
+
for (int target = 0; target < key->nr_color_regions; target++) {
/* Skip over outputs that weren't written. */
if (this->outputs[target].file == BAD_FILE)
ralloc_asprintf(this->mem_ctx, "FB write target %d", target));
fs_reg src0_alpha;
- if (devinfo->gen >= 6 && key->replicate_alpha && target != 0)
+ if (devinfo->gen >= 6 && prog_data->replicate_alpha && target != 0)
src0_alpha = offset(outputs[0], bld, 3);
inst = emit_single_fb_write(abld, this->outputs[target],
old_key->flat_shade, key->flat_shade);
found |= key_debug(brw, "number of color buffers",
old_key->nr_color_regions, key->nr_color_regions);
- found |= key_debug(brw, "MRT alpha test or alpha-to-coverage",
- old_key->replicate_alpha, key->replicate_alpha);
+ found |= key_debug(brw, "MRT alpha test",
+ old_key->alpha_test_replicate_alpha,
+ key->alpha_test_replicate_alpha);
+ found |= key_debug(brw, "alpha to coverage",
+ old_key->alpha_to_coverage, key->alpha_to_coverage);
found |= key_debug(brw, "fragment color clamping",
old_key->clamp_fragment_color, key->clamp_fragment_color);
found |= key_debug(brw, "per-sample interpolation",
key->force_dual_color_blend = brw->dual_color_blend_by_location &&
(ctx->Color.BlendEnabled & 1) && ctx->Color.Blend[0]._UsesDualSrc;
- /* _NEW_MULTISAMPLE, _NEW_COLOR, _NEW_BUFFERS */
- key->replicate_alpha = ctx->DrawBuffer->_NumColorDrawBuffers > 1 &&
- (_mesa_is_alpha_test_enabled(ctx) ||
- _mesa_is_alpha_to_coverage_enabled(ctx));
+ /* _NEW_MULTISAMPLE, _NEW_BUFFERS */
+ key->alpha_to_coverage = _mesa_is_alpha_to_coverage_enabled(ctx);
+
+ /* _NEW_COLOR, _NEW_BUFFERS */
+ key->alpha_test_replicate_alpha =
+ ctx->DrawBuffer->_NumColorDrawBuffers > 1 &&
+ _mesa_is_alpha_test_enabled(ctx);
/* _NEW_BUFFERS _NEW_MULTISAMPLE */
/* Ignore sample qualifier while computing this flag. */
projects / mesa.git / commitdiff