Text: Ignore Unicode joiners and modifiers

The fonts bundled with Lagrange currently do not have all the latest Unicode symbols, so we'll ignore the joiners and modifiers for gender and skin color.

A better option would be to fall back to system-provided text rendering, if that is available.

IssueID #81

2 files changed, 28 insertions, 4 deletions

diff --git a/src/ui/text.c b/src/ui/text.c
index a8be33b6..ae4b1714 100644
--- a/src/ui/text.c
+++ b/src/ui/text.c
@@ -665,6 +665,17 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
             }
         }
         iChar ch = nextChar_(&chPos, text.end);
+        if (ch == 0x200d) { /* zero-width joiner */
+            /* We don't have the composited Emojis. */
+            if (isEmoji_Char(prevCh)) {
+                /* skip */
+                ch = nextChar_(&chPos, text.end);
+                ch = nextChar_(&chPos, text.end);
+            }
+            else {
+                printf("it's %x\n", prevCh);
+            }
+        }
         if (isVariationSelector_Char(ch)) {
             /* TODO: VS15: Should peek ahead for this and prefer the Emoji font. */
             ch = nextChar_(&chPos, text.end); /* just ignore */
@@ -712,6 +723,9 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
                 prevCh = 0;
                 continue;
             }
+            if (isDefaultIgnorable_Char(ch) || isFitzpatrickType_Char(ch)) {
+                continue;
+            }
         }
         const iGlyph *glyph = glyph_Font_(d, ch);
         int x1 = xpos;
@@ -1000,7 +1014,7 @@ iString *renderBlockChars_Text(const iBlock *fontData, int height, enum iTextBlo
     size_t      strRemain = length_String(text);
     iConstForEach(String, i, text) {
         if (!strRemain) break;
-        if (i.value == variationSelectorEmoji_Char) {
+        if (isVariationSelector_Char(i.value) || isDefaultIgnorable_Char(i.value)) {
             strRemain--;
             continue;
         }
diff --git a/src/ui/text.h b/src/ui/text.h
index 5bae8e2a..a0b2dc1a 100644
--- a/src/ui/text.h
+++ b/src/ui/text.h
@@ -114,11 +114,21 @@ enum iFontId {
 iLocalDef iBool isJapanese_FontId(enum iFontId id) {
     return id >= defaultJapanese_FontId && id <= hugeJapanese_FontId;
 }
-iLocalDef iBool isVariationSelector_Char(iChar ch) {
-    return ch >= 0xfe00 && ch <= 0xfe0f;
+iLocalDef iBool isVariationSelector_Char(iChar c) {
+    return (c >= 0xfe00 && c <= 0xfe0f) || (c >= 0xe0100 && c <= 0xe0121);
+}
+iLocalDef iBool isFitzpatrickType_Char(iChar c) {
+    return c >= 0x1f3fb && c <= 0x1f3ff;
+}
+iLocalDef iBool isDefaultIgnorable_Char(iChar c) {
+    return c == 0x115f || (c >= 0x200b && c <= 0x200e) || c == 0x2060 || c == 0x2061 ||
+           c == 0xfeff;
+}
+iLocalDef iBool isEmoji_Char(iChar c) {
+    return (c >= 0x1f300 && c < 0x1f700) || (c >= 0x1f900 && c <= 0x1f9ff);
 }
 
-#define variationSelectorEmoji_Char     ((iChar) 0xfe0f)
+#define emojiVariationSelector_Char     ((iChar) 0xfe0f)
 
 enum iTextFont {
     nunito_TextFont,