Drawing document RTL text runs

The base text direction of each line of text is determined when the document is laid out. When drawing runs, use this predetermined base direction.

5 files changed, 104 insertions, 83 deletions

diff --git a/src/gmdocument.c b/src/gmdocument.c
index 34987beb..9fc270d2 100644
--- a/src/gmdocument.c
+++ b/src/gmdocument.c
@@ -337,7 +337,7 @@ static enum iGmDocumentTheme currentTheme_(void) {
 }
 
 static void alignDecoration_GmRun_(iGmRun *run, iBool isCentered) {
-    const iRect visBounds = visualBounds_Text(run->font, run->text);
+    const iRect visBounds = visualBounds_Text(run->textParams.font, run->text);
     const int   visWidth  = width_Rect(visBounds);
     int         xAdjust   = 0;
     if (!isCentered) {
@@ -414,12 +414,13 @@ static const int colors[max_GmLineType] = {
     tmLinkText_ColorId,
 };
 
-static iBool typesetOneLine_RunTypesetter_(iWrapText *wrap, iRangecc wrapRange, int origin, int advance) {
+static iBool typesetOneLine_RunTypesetter_(iWrapText *wrap, iRangecc wrapRange, int origin,
+                                           int advance, iBool isBaseRTL) {
     iAssert(wrapRange.start <= wrapRange.end);
     trimEnd_Rangecc(&wrapRange);
 //    printf("typeset: {%s}\n", cstr_Rangecc(wrapRange));
     iRunTypesetter *d = wrap->context;
-    const int fontId = d->run.font;
+    const int fontId = d->run.textParams.font;
     d->run.text = wrapRange;
     if (~d->run.flags & startOfLine_GmRunFlag && d->lineHeightReduction > 0.0f) {
         d->pos.y -= d->lineHeightReduction * lineHeight_Text(fontId);
@@ -431,6 +432,7 @@ static iBool typesetOneLine_RunTypesetter_(iWrapText *wrap, iRangecc wrapRange,
     d->run.bounds.size.y    = dims.y;
     d->run.visBounds        = d->run.bounds;
     d->run.visBounds.size.x = dims.x;
+    d->run.textParams.isRTL = isBaseRTL;    
     pushBack_Array(&d->layout, &d->run);
     d->run.flags &= ~startOfLine_GmRunFlag;
     d->pos.y += lineHeight_Text(fontId) * prefs_App()->lineSpacing;
@@ -520,7 +522,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
         if (*line.end == '\r') {
             line.end--; /* trim CR always */
         }
-        iGmRun run = { .color = white_ColorId };
+        iGmRun run = { .textParams = { .color = white_ColorId } };
         enum iGmLineType type;
         float indent = 0.0f;
         /* Detect the type of the line. */
@@ -565,7 +567,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                 }
             }
             trimLine_Rangecc(&line, type, isNormalized);
-            run.font = fonts[type];
+            run.textParams.font = fonts[type];
             /* Remember headings for the document outline. */
             if (type == heading1_GmLineType || type == heading2_GmLineType || type == heading3_GmLineType) {
                 pushBack_Array(
@@ -586,7 +588,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                 continue;
             }
             run.preId = preId;
-            run.font = (d->format == plainText_SourceFormat ? regularMonospace_FontId : preFont);
+            run.textParams.font = (d->format == plainText_SourceFormat ? regularMonospace_FontId : preFont);
             indent = indents[type];
         }
         if (addSiteBanner) {
@@ -601,9 +603,9 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                     banner.visBounds.size.y += iMaxi(6000 * lineHeight_Text(uiLabel_FontId) /
                                                          d->size.x, lineHeight_Text(uiLabel_FontId) * 5);
                 }
-                banner.font      = banner_FontId;
-                banner.text      = bannerText;
-                banner.color     = tmBannerTitle_ColorId;
+                banner.text             = bannerText;
+                banner.textParams.font  = banner_FontId;
+                banner.textParams.color = tmBannerTitle_ColorId;
                 pushBack_Array(&d->layout, &banner);
                 pos.y += height_Rect(banner.visBounds) +
                          lineHeight_Text(paragraph_FontId) * prefs->lineSpacing;
@@ -614,13 +616,13 @@ static void doLayout_GmDocument_(iGmDocument *d) {
             if (type == quote_GmLineType && !prefs->quoteIcon) {
                 /* For quote indicators we still need to produce a run. */
                 run.visBounds.pos  = addX_I2(pos, indents[type] * gap_Text);
-                run.visBounds.size = init_I2(gap_Text, lineHeight_Text(run.font));
+                run.visBounds.size = init_I2(gap_Text, lineHeight_Text(run.textParams.font));
                 run.bounds         = zero_Rect(); /* just visual */
                 run.flags          = quoteBorder_GmRunFlag | decoration_GmRunFlag;
                 run.text           = iNullRange;
                 pushBack_Array(&d->layout, &run);
             }
-            pos.y += lineHeight_Text(run.font) * prefs->lineSpacing;
+            pos.y += lineHeight_Text(run.textParams.font) * prefs->lineSpacing;
             prevType = type;
             if (type != quote_GmLineType) {
                 addQuoteIcon = prefs->quoteIcon;
@@ -664,13 +666,14 @@ static void doLayout_GmDocument_(iGmDocument *d) {
             const iGmPreMeta *meta = constAt_Array(&d->preMeta, preId - 1);
             if (meta->flags & folded_GmPreMetaFlag) {
                 const iBool isBlank = isEmpty_Range(&meta->altText);
-                iGmRun altText = { .font  = paragraph_FontId,
-                                   .flags = (isBlank ? decoration_GmRunFlag : 0) | altText_GmRunFlag };
+                iGmRun      altText = {
+                    .textParams = { .font = paragraph_FontId, .color = tmQuote_ColorId },
+                    .flags      = (isBlank ? decoration_GmRunFlag : 0) | altText_GmRunFlag
+                };
                 const iInt2 margin = preRunMargin_GmDocument(d, 0);
-                altText.color      = tmQuote_ColorId;
                 altText.text       = isBlank ? range_Lang(range_CStr("doc.pre.nocaption"))
                                              : meta->altText;
-                iInt2 size = measureWrapRange_Text(altText.font, d->size.x - 2 * margin.x,
+                iInt2 size = measureWrapRange_Text(altText.textParams.font, d->size.x - 2 * margin.x,
                                                    altText.text).bounds.size;
                 altText.bounds = altText.visBounds = init_Rect(pos.x, pos.y, d->size.x,
                                                                size.y + 2 * margin.y);
@@ -689,19 +692,19 @@ static void doLayout_GmDocument_(iGmDocument *d) {
             setRange_String(&d->title, line);
         }
         /* List bullet. */
-        run.color = colors[type];
+        run.textParams.color = colors[type];
         if (type == bullet_GmLineType) {
             /* TODO: Literata bullet is broken? */
             iGmRun bulRun = run;
             if (prefs->font == literata_TextFont) {
                 /* Something wrong this the glyph in Literata, looks cropped. */
-                bulRun.font = defaultContentRegular_FontId;
+                bulRun.textParams.font = defaultContentRegular_FontId;
             }
-            bulRun.color = tmQuote_ColorId;
+            bulRun.textParams.color = tmQuote_ColorId;
             bulRun.visBounds.pos = addX_I2(pos, (indents[text_GmLineType] - 0.55f) * gap_Text);
             bulRun.visBounds.size =
                 init_I2((indents[bullet_GmLineType] - indents[text_GmLineType]) * gap_Text,
-                        lineHeight_Text(bulRun.font));
+                        lineHeight_Text(bulRun.textParams.font));
             //            bulRun.visBounds.pos.x -= 4 * gap_Text - width_Rect(bulRun.visBounds) / 2;
             bulRun.bounds = zero_Rect(); /* just visual */
             bulRun.text   = range_CStr(bullet);
@@ -713,11 +716,11 @@ static void doLayout_GmDocument_(iGmDocument *d) {
         if (type == quote_GmLineType && addQuoteIcon) {
             addQuoteIcon    = iFalse;
             iGmRun quoteRun = run;
-            quoteRun.font   = heading1_FontId;
+            quoteRun.textParams.font   = heading1_FontId;
             quoteRun.text   = range_CStr(quote);
-            quoteRun.color  = tmQuoteIcon_ColorId;
-            iRect vis       = visualBounds_Text(quoteRun.font, quoteRun.text);
-            quoteRun.visBounds.size = measure_Text(quoteRun.font, quote).bounds.size;
+            quoteRun.textParams.color  = tmQuoteIcon_ColorId;
+            iRect vis       = visualBounds_Text(quoteRun.textParams.font, quoteRun.text);
+            quoteRun.visBounds.size = measure_Text(quoteRun.textParams.font, quote).bounds.size;
             quoteRun.visBounds.pos =
                 add_I2(pos,
                        init_I2((indents[quote_GmLineType] - 5) * gap_Text,
@@ -733,7 +736,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
         if (type == link_GmLineType) {
             iGmRun icon = run;
             icon.visBounds.pos  = pos;
-            icon.visBounds.size = init_I2(indent * gap_Text, lineHeight_Text(run.font));
+            icon.visBounds.size = init_I2(indent * gap_Text, lineHeight_Text(run.textParams.font));
             icon.bounds         = zero_Rect(); /* just visual */
             const iGmLink *link = constAt_PtrArray(&d->links, run.linkId - 1);
             icon.text           = range_CStr(link->flags & query_GmLinkFlag    ? magnifyingGlass
@@ -748,23 +751,23 @@ static void doLayout_GmDocument_(iGmDocument *d) {
             }
             /* TODO: List bullets needs the same centering logic. */
             /* Special exception for the tiny bullet operator. */
-            icon.font = equal_Rangecc(link->labelIcon, "\u2219") ? regularMonospace_FontId
+            icon.textParams.font = equal_Rangecc(link->labelIcon, "\u2219") ? regularMonospace_FontId
                                                                  : regular_FontId;
             alignDecoration_GmRun_(&icon, iFalse);
-            icon.color = linkColor_GmDocument(d, run.linkId, icon_GmLinkPart);
+            icon.textParams.color = linkColor_GmDocument(d, run.linkId, icon_GmLinkPart);
             icon.flags |= decoration_GmRunFlag;
             pushBack_Array(&d->layout, &icon);
         }
-        run.color = colors[type];
+        run.textParams.color = colors[type];
         if (d->format == plainText_SourceFormat) {
-            run.color = colors[text_GmLineType];
+            run.textParams.color = colors[text_GmLineType];
         }
         /* Special formatting for the first paragraph (e.g., subtitle, introduction, or lede). */
 //        int bigCount = 0;
         iBool isLedeParagraph = iFalse;
         if (type == text_GmLineType && isFirstText) {
-            if (!isMono) run.font = firstParagraph_FontId;
-            run.color = tmFirstParagraph_ColorId;
+            if (!isMono) run.textParams.font = firstParagraph_FontId;
+            run.textParams.color = tmFirstParagraph_ColorId;
 //            bigCount = 15; /* max lines -- what if the whole document is one paragraph? */
             isLedeParagraph = iTrue;
             isFirstText = iFalse;
@@ -811,7 +814,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                 }
                 /* Visited links are never bold. */
                 if (run.linkId && linkFlags_GmDocument(d, run.linkId) & visited_GmLinkFlag) {
-                    rts.run.font = paragraph_FontId;
+                    rts.run.textParams.font = paragraph_FontId;
                 }
             }
             if (!prefs->quoteIcon && type == quote_GmLineType) {
@@ -827,15 +830,15 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                                                .mode     = word_WrapTextMode,
                                                .wrapFunc = typesetOneLine_RunTypesetter_,
                                                .context  = &rts },
-                                 run.font);
+                                 run.textParams.font);
                 if (!isLedeParagraph || size_Array(&rts.layout) <= maxLedeLines_) {
                     commit_RunTypesetter_(&rts, d);
                     break;
                 }
                 clear_RunTypesetter_(&rts);
-                rts.pos         = pos;
-                rts.run.font    = rts.fonts[text_GmLineType];
-                rts.run.color   = colors   [text_GmLineType];
+                rts.pos                  = pos;
+                rts.run.textParams.font  = rts.fonts[text_GmLineType];
+                rts.run.textParams.color = colors[text_GmLineType];
                 isLedeParagraph = iFalse;
             }
             pos = rts.pos;
@@ -869,11 +872,11 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                     run.visBounds.pos.x  = run.bounds.size.x / 2 - width_Rect(run.visBounds) / 2;
                     run.bounds.size.y    = run.visBounds.size.y;
                 }
-                run.text      = iNullRange;
-                run.font      = 0;
-                run.color     = 0;
-                run.mediaType = image_GmRunMediaType;
-                run.mediaId   = imageId;
+                run.text             = iNullRange;
+                run.textParams.font  = 0;
+                run.textParams.color = 0;
+                run.mediaType        = image_GmRunMediaType;
+                run.mediaId          = imageId;
                 pushBack_Array(&d->layout, &run);
                 pos.y += run.bounds.size.y + margin;
             }
@@ -888,7 +891,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                 run.bounds.size.y = lineHeight_Text(uiContent_FontId) + 3 * gap_UI;
                 run.visBounds     = run.bounds;
                 run.text          = iNullRange;
-                run.color         = 0;
+                run.textParams.color = 0;
                 run.mediaType     = audio_GmRunMediaType;
                 run.mediaId       = audioId;
                 pushBack_Array(&d->layout, &run);
@@ -905,7 +908,7 @@ static void doLayout_GmDocument_(iGmDocument *d) {
                 run.bounds.size.y = 2 * lineHeight_Text(uiContent_FontId) + 4 * gap_UI;
                 run.visBounds     = run.bounds;
                 run.text          = iNullRange;
-                run.color         = 0;
+                run.textParams.color = 0;
                 run.mediaType     = download_GmRunMediaType;
                 run.mediaId       = downloadId;
                 pushBack_Array(&d->layout, &run);
@@ -1517,11 +1520,11 @@ static void markLinkRunsVisited_GmDocument_(iGmDocument *d, const iIntSet *linkI
     iForEach(Array, r, &d->layout) {
         iGmRun *run = r.value;
         if (run->linkId && !run->mediaId && contains_IntSet(linkIds, run->linkId)) {
-            if (run->font == bold_FontId) {
-                run->font = paragraph_FontId;
+            if (run->textParams.font == bold_FontId) {
+                run->textParams.font = paragraph_FontId;
             }
             else if (run->flags & decoration_GmRunFlag) {
-                run->color = linkColor_GmDocument(d, run->linkId, icon_GmLinkPart);
+                run->textParams.color = linkColor_GmDocument(d, run->linkId, icon_GmLinkPart);
             }
         }
     }
@@ -2008,7 +2011,7 @@ iRangecc findLoc_GmRun(const iGmRun *d, iInt2 pos) {
         return (iRangecc){ d->text.start, d->text.start };
     }
     iRangecc loc;
-    tryAdvanceNoWrap_Text(d->font, d->text, x, &loc.start);
+    tryAdvanceNoWrap_Text(d->textParams.font, d->text, x, &loc.start);
     loc.end = loc.start;
     iChar ch;
     if (d->text.end != loc.start) {
diff --git a/src/gmdocument.h b/src/gmdocument.h
index 0d50e6ad..9d906006 100644
--- a/src/gmdocument.h
+++ b/src/gmdocument.h
@@ -128,8 +128,11 @@ struct Impl_GmRun {
     iRangecc  text;
     iRect     bounds;    /* used for hit testing, may extend to edges */
     iRect     visBounds; /* actual visual bounds */
-    uint8_t   font;
-    uint8_t   color;
+    struct {
+        uint16_t   color : 8;
+        uint16_t   font  : 7;
+        uint16_t   isRTL : 1;
+    } textParams;
     uint8_t   flags;
     uint8_t   mediaType;
     uint16_t  preId;     /* preformatted block ID (sequential) */
diff --git a/src/ui/documentwidget.c b/src/ui/documentwidget.c
index 3c6c0039..ea4909eb 100644
--- a/src/ui/documentwidget.c
+++ b/src/ui/documentwidget.c
@@ -1585,7 +1585,7 @@ static void parseUser_DocumentWidget_(iDocumentWidget *d) {
 static void cacheRunGlyphs_(void *data, const iGmRun *run) {
     iUnused(data);
     if (!isEmpty_Range(&run->text)) {
-        cache_Text(run->font, run->text);
+        cache_Text(run->textParams.font, run->text);
     }
 }
 
@@ -3910,14 +3910,14 @@ static void fillRange_DrawContext_(iDrawContext *d, const iGmRun *run, enum iCol
                       contains_Range(&mark, run->text.start))) {
         int x = 0;
         if (!*isInside) {
-            x = measureRange_Text(run->font,
+            x = measureRange_Text(run->textParams.font,
                                   (iRangecc){ run->text.start, iMax(run->text.start, mark.start) })
                     .advance.x;
         }
         int w = width_Rect(run->visBounds) - x;
         if (contains_Range(&run->text, mark.end) || mark.end < run->text.start) {
             w = measureRange_Text(
-                    run->font,
+                    run->textParams.font,
                     !*isInside ? mark
                                : (iRangecc){ run->text.start, iMax(run->text.start, mark.end) })
                     .advance.x;
@@ -3973,15 +3973,15 @@ static void drawBannerRun_DrawContext_(iDrawContext *d, const iGmRun *run, iInt2
     iInt2 bpos = add_I2(visPos, init_I2(0, lineHeight_Text(banner_FontId) / 2));
     if (icon) {
         appendChar_String(&str, icon);
-        const iRect iconRect = visualBounds_Text(run->font, range_String(&str));
+        const iRect iconRect = visualBounds_Text(run->textParams.font, range_String(&str));
         drawRange_Text(
-            run->font,
-            addY_I2(bpos, -mid_Rect(iconRect).y + lineHeight_Text(run->font) / 2),
+            run->textParams.font,
+            addY_I2(bpos, -mid_Rect(iconRect).y + lineHeight_Text(run->textParams.font) / 2),
             tmBannerIcon_ColorId,
             range_String(&str));
         bpos.x += right_Rect(iconRect) + 3 * gap_Text;
     }
-    drawRange_Text(run->font,
+    drawRange_Text(run->textParams.font,
                    bpos,
                    tmBannerTitle_ColorId,
                    bannerText_DocumentWidget_(d->widget));
@@ -4088,7 +4088,7 @@ static void drawRun_DrawContext_(void *context, const iGmRun *run) {
         /* Media UIs are drawn afterwards as a dynamic overlay. */
         return;
     }
-    enum iColorId      fg        = run->color;
+    enum iColorId      fg        = run->textParams.color;
     const iGmDocument *doc       = d->widget->doc;
     const int          linkFlags = linkFlags_GmDocument(doc, run->linkId);
     /* Hover state of a link. */
@@ -4152,8 +4152,11 @@ static void drawRun_DrawContext_(void *context, const iGmRun *run) {
         const iInt2 margin = preRunMargin_GmDocument(doc, run->preId);
         fillRect_Paint(&d->paint, (iRect){ visPos, run->visBounds.size }, tmBackgroundAltText_ColorId);
         drawRect_Paint(&d->paint, (iRect){ visPos, run->visBounds.size }, tmQuoteIcon_ColorId);
-        drawWrapRange_Text(run->font, add_I2(visPos, margin),
-                           run->visBounds.size.x - 2 * margin.x, run->color, run->text);
+        drawWrapRange_Text(run->textParams.font,
+                           add_I2(visPos, margin),
+                           run->visBounds.size.x - 2 * margin.x,
+                           run->textParams.color,
+                           run->text);
     }
     else if (run->flags & siteBanner_GmRunFlag) {
         /* Banner background. */
@@ -4194,7 +4197,11 @@ static void drawRun_DrawContext_(void *context, const iGmRun *run) {
                             height_Rect(run->visBounds),
                             tmQuoteIcon_ColorId);
         }
-        drawBoundRange_Text(run->font, visPos, width_Rect(run->visBounds), fg, run->text);
+        drawBoundRange_Text(run->textParams.font,
+                            visPos,
+                            (run->textParams.isRTL ? -1 : 1) * width_Rect(run->visBounds),
+                            fg,
+                            run->text);
     runDrawn:;
     }
     /* Presentation of links. */
diff --git a/src/ui/text.c b/src/ui/text.c
index e1638368..03ce46c7 100644
--- a/src/ui/text.c
+++ b/src/ui/text.c
@@ -792,7 +792,8 @@ struct Impl_AttributedRun {
 };
 
 iDeclareType(AttributedText)
-iDeclareTypeConstructionArgs(AttributedText, iRangecc text, size_t maxLen, iFont *font, iColor fgColor)
+iDeclareTypeConstructionArgs(AttributedText, iRangecc text, size_t maxLen, iFont *font,
+                             iColor fgColor, int baseDir)
 
 struct Impl_AttributedText {
     iRangecc  source;   /* original source text */
@@ -809,8 +810,9 @@ struct Impl_AttributedText {
     iBool     isBaseRTL;
 };
 
-iDefineTypeConstructionArgs(AttributedText, (iRangecc text, size_t maxLen, iFont *font, iColor fgColor),
-                            text, maxLen, font, fgColor)
+iDefineTypeConstructionArgs(AttributedText,
+                            (iRangecc text, size_t maxLen, iFont *font, iColor fgColor, int baseDir),
+                            text, maxLen, font, fgColor, baseDir)
 
 static const char *sourcePtr_AttributedText_(const iAttributedText *d, int logicalPos) {
     const int *logToSource = constData_Array(&d->logicalToSourceOffset);
@@ -867,7 +869,7 @@ static enum iFontId fontId_Text_(const iFont *font) {
     return (enum iFontId) (font - text_.fonts);
 }
 
-static void prepare_AttributedText_(iAttributedText *d) {
+static void prepare_AttributedText_(iAttributedText *d, int overrideBaseDir) {
     iAssert(isEmpty_Array(&d->runs));
     size_t length = 0;
     /* Prepare the UTF-32 logical string. */ {
@@ -896,7 +898,7 @@ static void prepare_AttributedText_(iAttributedText *d) {
                         data_Array(&d->logicalToVisual),
                         data_Array(&d->visualToLogical),
                         (FriBidiLevel *) d->bidiLevels);
-        d->isBaseRTL = FRIBIDI_IS_RTL(baseDir);
+        d->isBaseRTL = (overrideBaseDir == 0 ? FRIBIDI_IS_RTL(baseDir) : (overrideBaseDir < 0));
 #endif
     }
     /* The mapping needs to include the terminating NULL position. */ {
@@ -1017,7 +1019,8 @@ static void prepare_AttributedText_(iAttributedText *d) {
 #endif
 }
 
-void init_AttributedText(iAttributedText *d, iRangecc text, size_t maxLen, iFont *font, iColor fgColor) {
+void init_AttributedText(iAttributedText *d, iRangecc text, size_t maxLen, iFont *font, iColor fgColor,
+                         int baseDir) {
     d->source  = text;
     d->maxLen  = maxLen ? maxLen : iInvalidSize;
     d->font    = font;
@@ -1030,7 +1033,7 @@ void init_AttributedText(iAttributedText *d, iRangecc text, size_t maxLen, iFont
     init_Array(&d->logicalToSourceOffset, sizeof(int));
     d->bidiLevels = NULL;
     d->isBaseRTL = iFalse;
-    prepare_AttributedText_(d);
+    prepare_AttributedText_(d, baseDir);
 }
 
 void deinit_AttributedText(iAttributedText *d) {
@@ -1181,7 +1184,7 @@ static void cacheTextGlyphs_Font_(iFont *d, const iRangecc text) {
     iArray glyphIndices;
     init_Array(&glyphIndices, sizeof(uint32_t));
     iAttributedText attrText;
-    init_AttributedText(&attrText, text, 0, d, (iColor){});
+    init_AttributedText(&attrText, text, 0, d, (iColor){}, 0);
     /* We use AttributedText here so the font lookup matches the behavior during text drawing --
        glyphs may be selected from a font that's different than `d`. */
     const iChar *logicalText = constData_Array(&attrText.logical);
@@ -1229,9 +1232,10 @@ struct Impl_RunArgs {
     size_t        maxLen; /* max characters to process */
     iInt2         pos;
     iWrapText *   wrap;
-    int           xposLimit;       /* hard limit for wrapping */
-    int           xposLayoutBound; /* visible bound for layout purposes; does not affect wrapping */
+    int           xposLimit;        /* hard limit for wrapping */
+    int           xposLayoutBound;  /* visible bound for layout purposes; does not affect wrapping */
     int           color;
+    int           baseDir;
     /* TODO: Cleanup using TextMetrics
        Use TextMetrics output pointer instead of return value & cursorAdvance_out. */
     iInt2 *       cursorAdvance_out;
@@ -1239,13 +1243,13 @@ struct Impl_RunArgs {
     int *         runAdvance_out;
 };
 
-static iBool notify_WrapText_(iWrapText *d, const char *ending, int origin, int advance) {
+static iBool notify_WrapText_(iWrapText *d, const char *ending, int origin, int advance, iBool isBaseRTL) {
     if (d && d->wrapFunc && d->wrapRange_.start) {
         /* `wrapRange_` uses logical indices. */
-        const char *end = ending ? ending : d->wrapRange_.end;
-        iRangecc range = { d->wrapRange_.start, end };
+        const char *end   = ending ? ending : d->wrapRange_.end;
+        iRangecc    range = { d->wrapRange_.start, end };
         iAssert(range.start <= range.end);
-        const iBool result = d->wrapFunc(d, range, origin, advance);
+        const iBool result = d->wrapFunc(d, range, origin, advance, isBaseRTL);
         if (result) {
             d->wrapRange_.start = end;
         }
@@ -1380,7 +1384,8 @@ static iRect run_Font_(iFont *d, const iRunArgs *args) {
        font is used and other attributes such as color. (HarfBuzz shaping is done
        with one specific font.) */
     iAttributedText attrText;
-    init_AttributedText(&attrText, args->text, args->maxLen, d, get_Color(args->color));
+    init_AttributedText(&attrText, args->text, args->maxLen, d, get_Color(args->color),
+                        args->baseDir);
     if (args->wrap) {
         /* TODO: Duplicated args? */
         iAssert(equalRange_Rangecc(args->wrap->text, args->text));
@@ -1390,7 +1395,7 @@ static iRect run_Font_(iFont *d, const iRunArgs *args) {
     const iChar *logicalText = constData_Array(&attrText.logical);
     const iChar *visualText  = constData_Array(&attrText.visual);
     const int *  logToVis    = constData_Array(&attrText.logicalToVisual);
-    const int *  visToLog    = constData_Array(&attrText.visualToLogical);
+//    const int *  visToLog    = constData_Array(&attrText.visualToLogical);
     const size_t runCount    = size_Array(&attrText.runs);
     iArray buffers;
     init_Array(&buffers, sizeof(iGlyphBuffer));
@@ -1580,7 +1585,8 @@ static iRect run_Font_(iFont *d, const iRunArgs *args) {
         if (!notify_WrapText_(args->wrap,
                               sourcePtr_AttributedText_(&attrText, wrapResumePos),
                               origin,
-                              iRound(wrapAdvance))) {
+                              iRound(wrapAdvance),
+                              attrText.isBaseRTL)) {
             willAbortDueToWrap = iTrue;
         }
         xCursor = origin;
@@ -1743,8 +1749,9 @@ static int runFlagsFromId_(enum iFontId fontId) {
     return runFlags;
 }
 
-static iBool cbAdvanceOneLine_(iWrapText *d, iRangecc range, int origin, int advance) {
-    iUnused(origin, advance);
+static iBool cbAdvanceOneLine_(iWrapText *d, iRangecc range, int origin, int advance,
+                               iBool isBaseRTL) {
+    iUnused(origin, advance, isBaseRTL);
     *((const char **) d->context) = range.end;
     return iFalse; /* just one line */
 }
@@ -1785,9 +1792,9 @@ iTextMetrics measureN_Text(int fontId, const char *text, size_t n) {
 }
 
 static void drawBoundedN_Text_(int fontId, iInt2 pos, int xposBound, int color, iRangecc text, size_t maxLen) {
-    iText *d    = &text_;
-    iFont *font = font_Text_(fontId);
-    const iColor clr = get_Color(color & mask_ColorId);
+    iText *      d    = &text_;
+    iFont *      font = font_Text_(fontId);
+    const iColor clr  = get_Color(color & mask_ColorId);
     SDL_SetTextureColorMod(d->cache, clr.r, clr.g, clr.b);
     run_Font_(font,
               &(iRunArgs){ .mode = draw_RunMode |
@@ -1798,7 +1805,8 @@ static void drawBoundedN_Text_(int fontId, iInt2 pos, int xposBound, int color,
                            .maxLen          = maxLen,                           
                            .pos             = pos,
                            .xposLayoutBound = xposBound,
-                           .color           = color & mask_ColorId });
+                           .color           = color & mask_ColorId,
+                           .baseDir         = xposBound ? iSign(xposBound - pos.x) : 0 });
 }
 
 static void drawBounded_Text_(int fontId, iInt2 pos, int xposBound, int color, iRangecc text) {
diff --git a/src/ui/text.h b/src/ui/text.h
index 341f94da..4630b9f6 100644
--- a/src/ui/text.h
+++ b/src/ui/text.h
@@ -205,7 +205,7 @@ struct Impl_WrapText {
     iRangecc text;
     int      maxWidth;
     enum iWrapTextMode mode;
-    iBool  (*wrapFunc)(iWrapText *, iRangecc wrappedText, int origin, int advance);
+    iBool  (*wrapFunc)(iWrapText *, iRangecc wrappedText, int origin, int advance, iBool isBaseRTL);
     void *   context;
     /* internal */
     iRangecc wrapRange_;