Support more items for QTextCharFormat::VerticalAlignment enum for custom text objects.

* QTextCharFormat::AlignNormal - support text format descent, place text object bottom on (baseline - descent).
 * QTextCharFormat::AlignBottom - place text object bottom on baseline.
 * QTextCharFormat::AlignTop - Still not supported.
 * Any other vertical alignment is mapped QTextCharFormat::AlignBottom.

Add new enum AlignBaseline for custom inline objects to take into account font baseline.

Merge-request: 2578
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com>
(cherry picked from commit ee9455ed2a83084692d969c398ecb91bcd4fc33a)

src/gui/text/qtextdocumentlayout.cpp

@@ -2996,10 +2996,19 @@ void QTextDocumentLayout::resizeInlineObject(QTextInlineObject item, int posInDo
 
     QSizeF inlineSize = (pos == QTextFrameFormat::InFlow ? intrinsic : QSizeF(0, 0));
     item.setWidth(inlineSize.width());
-    if (f.verticalAlignment() == QTextCharFormat::AlignMiddle) {
+
+    QFontMetrics m(f.font());
+    switch (f.verticalAlignment())
+    {
+    case QTextCharFormat::AlignMiddle:
         item.setDescent(inlineSize.height() / 2);
         item.setAscent(inlineSize.height() / 2 - 1);
-    } else {
+        break;
+    case QTextCharFormat::AlignBaseline:
+        item.setDescent(m.descent());
+        item.setAscent(inlineSize.height() - m.descent() - 1);
+        break;
+    default:
         item.setDescent(0);
         item.setAscent(inlineSize.height() - 1);
     }

src/gui/text/qtextformat.h

@@ -378,7 +378,8 @@ public:
         AlignSubScript,
         AlignMiddle,
         AlignTop,
-        AlignBottom
+        AlignBottom,
+        AlignBaseline
     };
     enum UnderlineStyle { // keep in sync with Qt::PenStyle!
         NoUnderline,