New monospace font; flexible mono spacing

Iosevka replaces Fira Mono as the monospace font.

Emojis are now allowed to be wider than normal monospace glyphs. However, if whitespace permits, the original monospacing is restored.

IssueID #73

2 files changed, 45 insertions, 27 deletions

diff --git a/src/ui/text.c b/src/ui/text.c
index 4229217c..ec240c75 100644
--- a/src/ui/text.c
+++ b/src/ui/text.c
@@ -120,10 +120,10 @@ static void init_Font(iFont *d, const iBlock *data, int height, float scale,
             d->xScale *= floorf(advance) / advance;
         }
     }
-    d->vertOffset = height * (1.0f - scale) / 2;
+    d->vertOffset = height * (1.0f - scale) / 2;    
     int ascent;
     stbtt_GetFontVMetrics(&d->font, &ascent, NULL, NULL);
-    d->baseline     = ceil(ascent * d->yScale);
+    d->baseline     = /*ceil*/(ascent * d->yScale);
     d->symbolsFont  = symbolsFont;
     d->japaneseFont = regularJapanese_FontId;
     d->koreanFont   = regularKorean_FontId;
@@ -176,8 +176,8 @@ static iText text_;
 
 static void initFonts_Text_(iText *d) {
     const float textSize = fontSize_UI * d->contentFontSize;
-    const float monoSize = fontSize_UI * d->contentFontSize / contentScale_Text_ * 0.866f;
-    const float smallMonoSize = monoSize * 0.866f;
+    const float monoSize = textSize * 0.71f; //fontSize_UI * d->contentFontSize / contentScale_Text_ * 1.0f; //0.866f;
+    const float smallMonoSize = monoSize * 0.8f;
     const iBlock *regularFont  = &fontNunitoRegular_Embedded;
     const iBlock *italicFont   = &fontNunitoLightItalic_Embedded;
     const iBlock *h12Font      = &fontNunitoExtraBold_Embedded;
@@ -226,12 +226,12 @@ static void initFonts_Text_(iText *d) {
         { &fontSourceSansProRegular_Embedded, fontSize_UI,          1.0f, defaultSymbols_FontId },
         { &fontSourceSansProRegular_Embedded, fontSize_UI * 1.125f, 1.0f, defaultMediumSymbols_FontId },
         { &fontSourceSansProRegular_Embedded, fontSize_UI * 1.666f, 1.0f, defaultLargeSymbols_FontId },
-        { &fontFiraMonoRegular_Embedded,      fontSize_UI * 0.866f, 1.0f, defaultSymbols_FontId },
+        { &fontIosevkaTermExtended_Embedded,  fontSize_UI * 0.866f, 1.0f, defaultSymbols_FontId },
         { &fontSourceSansProRegular_Embedded, textSize,             scaling, symbols_FontId },
         /* content fonts */
         { regularFont,                        textSize,             scaling,      symbols_FontId },
-        { &fontFiraMonoRegular_Embedded,      monoSize,             1.0f,         monospaceSymbols_FontId },
-        { &fontFiraMonoRegular_Embedded,      smallMonoSize,        1.0f,         monospaceSmallSymbols_FontId },
+        { &fontIosevkaTermExtended_Embedded,  monoSize,             1.0f,         monospaceSymbols_FontId },
+        { &fontIosevkaTermExtended_Embedded,  smallMonoSize,        1.0f,         monospaceSmallSymbols_FontId },
         { regularFont,                        textSize * 1.200f,    scaling,      mediumSymbols_FontId },
         { h3Font,                             textSize * 1.333f,    h123Scaling,  bigSymbols_FontId },
         { italicFont,                         textSize,             scaling,      symbols_FontId },
@@ -239,7 +239,7 @@ static void initFonts_Text_(iText *d) {
         { h12Font,                            textSize * 2.000f,    h123Scaling,  hugeSymbols_FontId },
         { lightFont,                          textSize * 1.666f,    lightScaling, largeSymbols_FontId },
         /* monospace content fonts */
-        { &fontFiraMonoRegular_Embedded,      textSize,             0.8f, symbols_FontId },
+        { &fontIosevkaTermExtended_Embedded,  textSize,             0.866f, symbols_FontId },
         /* symbol fonts */
         { &fontSymbola_Embedded,              fontSize_UI,          1.0f, defaultSymbols_FontId },
         { &fontSymbola_Embedded,              fontSize_UI * 1.125f, 1.0f, defaultMediumSymbols_FontId },
@@ -288,7 +288,7 @@ static void initFonts_Text_(iText *d) {
                   fontData[i].size,
                   fontData[i].scaling,
                   fontData[i].symbolsFont,
-                  fontData[i].ttf == &fontFiraMonoRegular_Embedded);
+                  fontData[i].ttf == &fontIosevkaTermExtended_Embedded);
         if (i == default_FontId || i == defaultMedium_FontId) {
             font->manualKernOnly = iTrue;
         }
@@ -636,6 +636,7 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
     iRect bounds = zero_Rect();
     const iInt2 orig = pos;
     float xpos = pos.x;
+    float xposExtend = pos.x; /* allows wide glyphs to use more space; restored by whitespace */
     float xposMax = xpos;
     float monoAdvance = 0;
     iAssert(xposLimit == 0 || isMeasuring_(mode));
@@ -668,6 +669,7 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
             }
         }
         iChar ch = nextChar_(&chPos, text.end);
+        iBool isEmoji = isEmoji_Char(ch);
         if (ch == 0x200d) { /* zero-width joiner */
             /* We don't have the composited Emojis. */
             if (isEmoji_Char(prevCh)) {
@@ -676,9 +678,19 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
                 ch = nextChar_(&chPos, text.end);
             }
         }
+#if 0
+        iChar nextCh = 0; {
+            /* TODO: Since we're peeking ahead, should use this on the next loop iteration. */
+            const char *ncp = chPos;
+            nextCh = nextChar_(&ncp, text.end);
+        }
+        /* VS15: Peek ahead and treat as Emoji font. */
+        if (nextCh == emojiVariationSelector_Char) {
+            isEmoji = iTrue;
+        }
+#endif
         if (isVariationSelector_Char(ch)) {
-            /* TODO: VS15: Should peek ahead for this and prefer the Emoji font. */
-            ch = nextChar_(&chPos, text.end); /* just ignore */
+            ch = nextChar_(&chPos, text.end); /* skip it */
         }
         /* Special instructions. */ {
             if (ch == 0xad) { /* soft hyphen */
@@ -703,7 +715,7 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
                 }
             }
             if (ch == '\n') {
-                xpos = pos.x;
+                xpos = xposExtend = pos.x;
                 pos.y += d->height;
                 prevCh = ch;
                 continue;
@@ -711,6 +723,7 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
             if (ch == '\t') {
                 const int tabStopWidth = d->height * 8;
                 xpos = pos.x + ((int) ((xpos - pos.x) / tabStopWidth) + 1) * tabStopWidth;
+                xposExtend = iMax(xposExtend, xpos);
                 prevCh = 0;
                 continue;
             }
@@ -728,7 +741,7 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
             }
         }
         const iGlyph *glyph = glyph_Font_(d, ch);
-        int x1 = xpos;
+        int x1 = iMax(xpos, xposExtend);
         const int hoff = enableHalfPixelGlyphs_Text ? (xpos - x1 > 0.5f ? 1 : 0) : 0;
         int x2 = x1 + glyph->rect[hoff].size.x;
         /* Out of the allotted space? */
@@ -765,11 +778,13 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
             bounds.size.x = iMax(bounds.size.x, x2 - orig.x);
             bounds.size.y = iMax(bounds.size.y, pos.y + glyph->font->height - orig.y);
         }
+        /* Symbols and emojis are NOT monospaced, so must conform when the primary font
+           is monospaced. Except with Japanese script, that's larger than the normal monospace. */
         const iBool useMonoAdvance =
             monoAdvance > 0 && !isJapanese_FontId(fontId_Text_(glyph->font));
         const float advance = (useMonoAdvance ? monoAdvance : glyph->advance);
         if (!isMeasuring_(mode)) {
-            if (useMonoAdvance && dst.w > advance && glyph->font != d) {
+            if (useMonoAdvance && dst.w > advance && glyph->font != d && !isEmoji) {
                 /* Glyphs from a different font may need recentering to look better. */
                 dst.x -= (dst.w - advance) / 2;
             }
@@ -784,10 +799,12 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
             }
             SDL_RenderCopy(text_.render, text_.cache, &src, &dst);
         }
-        /* Symbols and emojis are NOT monospaced, so must conform when the primary font
-           is monospaced. Except with Japanese script, that's larger than the normal monospace. */
         xpos += advance;
-        xposMax = iMax(xposMax, xpos);
+        if (!isSpace_Char(ch)) {
+            xposExtend += isEmoji ? glyph->advance : advance;
+        }
+        xposExtend = iMax(xposExtend, xpos);
+        xposMax    = iMax(xposMax, xposExtend);
         if (continueFrom_out && ((mode & noWrapFlag_RunMode) || isWrapBoundary_(prevCh, ch))) {
             lastWordEnd = chPos;
         }
diff --git a/src/ui/text.h b/src/ui/text.h
index 6728bb62..5867a84b 100644
--- a/src/ui/text.h
+++ b/src/ui/text.h
@@ -127,7 +127,8 @@ iLocalDef iBool isDefaultIgnorable_Char(iChar c) {
            c == 0xfeff;
 }
 iLocalDef iBool isEmoji_Char(iChar c) {
-    return (c >= 0x1f300 && c < 0x1f700) || (c >= 0x1f900 && c <= 0x1f9ff);
+    return (c >= 0x1f300 && c < 0x1f700) || (c >= 0x1f7e0 && c <= 0x1f7eb) ||
+           (c >= 0x1f900 && c <= 0x1f9ff);
 }
 
 #define emojiVariationSelector_Char     ((iChar) 0xfe0f)
@@ -141,21 +142,21 @@ enum iTextFont {
 
 extern int gap_Text; /* affected by content font size */
 
-void    init_Text           (SDL_Renderer *);
-void    deinit_Text         (void);
+void    init_Text               (SDL_Renderer *);
+void    deinit_Text             (void);
 
 void    setContentFont_Text     (enum iTextFont font);
 void    setHeadingFont_Text     (enum iTextFont font);
 void    setContentFontSize_Text (float fontSizeFactor); /* affects all except `default*` fonts */
 void    resetFonts_Text         (void);
 
-int     lineHeight_Text     (int fontId);
-iInt2   measure_Text        (int fontId, const char *text);
-iInt2   measureRange_Text   (int fontId, iRangecc text);
-iRect   visualBounds_Text   (int fontId, iRangecc text);
-iInt2   advance_Text        (int fontId, const char *text);
-iInt2   advanceN_Text       (int fontId, const char *text, size_t n); /* `n` in characters */
-iInt2   advanceRange_Text   (int fontId, iRangecc text);
+int     lineHeight_Text         (int fontId);
+iInt2   measure_Text            (int fontId, const char *text);
+iInt2   measureRange_Text       (int fontId, iRangecc text);
+iRect   visualBounds_Text       (int fontId, iRangecc text);
+iInt2   advance_Text            (int fontId, const char *text);
+iInt2   advanceN_Text           (int fontId, const char *text, size_t n); /* `n` in characters */
+iInt2   advanceRange_Text       (int fontId, iRangecc text);
 iInt2   advanceWrapRange_Text   (int fontId, int maxWidth, iRangecc text);
 
 iInt2   tryAdvance_Text         (int fontId, iRangecc text, int width, const char **endPos);