<div id="gwp597db67c"><div id="gwp597db67ch"><div data-color-mode="light" class="gwp597db67cb" data-message-body="true"><div>I have investigated the situation further and it seems that defect in the Unicode 13.0—17.0 mapping is even more fundamental than I previously thought. In particular, the proposal L2/25-037 does not acknowledge the proposal L2/00-159, which had already been incorporated into Unicode 3.2. In that proposal, the description of characters U+23B8 (LEFT VERTICAL BOX LINE) and U+23B9 (RIGHT VERTICAL BOX LINE) exactly matches the proposed characters L2/25-037:1FBFC (BOX DRAWINGS LIGHT LEFT EDGE) and L2/25-037:1FBFD (BOX DRAWINGS LIGHT RIGHT EDGE). In both proposals, those two characters are specified to be aligned to left or right edge, span the entire edge (extending to the top and bottom), and match the thickness of Box Drawings Light lines. The description of the characters U+23BA (HORIZONTAL SCAN LINE-1) and U+23BD (HORIZONTAL SCAN LINE-9) also exactly matches the proposed characters L2/25-037:1FBFA (BOX DRAWINGS LIGHT TOP EDGE) and L2/25-037:1FBFB (BOX DRAWINGS LIGHT BOTTOM EDGE). In both proposals, those two characters are specified to be aligned to top and bottom edges, span the entire edge (extending to the left and right), and match the thickness of Box Drawings Light lines. However, the proposal L2/00-159 had already set precedent for usage of [U+23BA, U+23BD, U+23B8, U+23B9] (and not the 1÷8 blocks or 1÷4 blocks) in mapping to certain platforms such as The Heath/Zenith 19 Graphics Character Set and The DEC Special Graphics Character Set. This contrasts with the usage of 1÷8 blocks [U+2594, U+2581, U+258F, U+2595] and other related 1÷8 or 7÷8 block characters in the mapping to PETSCII and Apple II. <span style="color: rgb(44, 47, 69); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; float: none; display: inline !important;"><span class="font" style="font-family:Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif, "Segoe UI Emoji", "Segoe UI Symbol", "Apple Color Emoji""><span class="size" style="font-size:14px">Therefore there is a discrepancy between the legacy platforms added in Unicode 3.2 (which use the box drawing lines 23B8, 23B9, 23BA, 23BD) and the legacy platforms added in Unicode 13.0—17.0 (which use 1÷8 blocks 2594, 2581, 258F, 2595).</span></span></span><br></div><div><br></div><div class="gwp597db67c_nh_extra"><p>Dnia 25 października 2025 10:27 piotrunio-2004@wp.pl via Unicode <unicode@corp.unicode.org> napisał(a):<br></p><blockquote class="gwp597db67c_nh_quote gwp597db67c_bd-l_base gwp597db67c_bd-c_primary.50 gwp597db67c_pl_2 gwp597db67c_m_0"><div id="gwp597db67c_gwp60137106"><div id="gwp597db67c_gwp60137106h"><div data-color-mode="light" data-message-body="true" class="gwp597db67c_gwp60137106b"><div id="gwp597db67c_gwp60137106_gwp52beef1f"><div id="gwp597db67c_gwp60137106_gwp52beef1fh"><div data-message-body="true" class="gwp597db67c_gwp60137106_gwp52beef1fb"><div><br></div><div class="gwp597db67c_gwp60137106_gwp52beef1f_nh_extra"><p>Dnia 25 października 2025 08:29 Asmus Freytag via Unicode <unicode@corp.unicode.org> napisał(a):<br></p><blockquote class="gwp597db67c_gwp60137106_gwp52beef1f_nh_quote gwp597db67c_gwp60137106_gwp52beef1f_bd-l_base gwp597db67c_gwp60137106_gwp52beef1f_bd-c_primary.50 gwp597db67c_gwp60137106_gwp52beef1f_pl_2 gwp597db67c_gwp60137106_gwp52beef1f_m_0"><div id="gwp597db67c_gwp60137106_gwp52beef1f_gwpcee74020"><div id="gwp597db67c_gwp60137106_gwp52beef1f_gwpcee74020h"><div class="gwp597db67c_gwp60137106_gwp52beef1f_gwpcee74020b" data-message-body="true"><p>Again, the identity of the Unicode character is giving by
encoding the intended mappings. If Unicode decides to map the same
character to similar characters on different platforms, that is
not a problem, as long as implementers know that the intent is to
use a platform-specific rendering (and not assume that there is
only one possible rendering per character).<br></p><p>If you feel that the guidance available to implementers in the
text of the standard or in an annotation of the nameslist is not
sufficent, then the remedy would be to ask for the explanation to
be updated. We are unfortunately locked in as far as character
names are concerned, but we can add a note (best in the text of
the standard) that explains that emulators for some systems will
need an adjusted design so a sequence or other arrangement of
these characters looks correct.<br></p></div></div></div></blockquote></div><div>Indeed the character names cannot be changed due to stability policies. An explanation note has been provided for U+1FB81 that claims "The lines corresponding to 3 and 5 are not
actually block elements, but can show any horizontally
repeating pattern", but still implicitly enforces 1÷8 blocks for top and bottom. However, this doesn't address other cases such as the PETSCII C64 variation. And if 1FB70—1FB81 1FBB5—1FBB8 1FBBC were all noted to no longer require exact 1÷8 blocks, that would also not remedy the issue because it would introduce an inconsistency with the existing 1÷8 or 7÷8 block characters 2581 2589 258F 2594—2595, which already have established compatibility precedents that require the exact fraction, but are also used in the Unicode 13.0 mapping to PETSCII and Apple II character sets despite those platforms using varying thickness (consistent with light box drawings, except for the 1÷8 top and bottom blocks in C64, where the 1÷4 top and bottom blocks are made consistent instead).<br></div></div></div></div><div><br></div></div></div></div></blockquote></div><div><br></div></div></div><div><br></div></div><div><br></div>