Compute metrics of *TeX* logos using draw and a null painter

Instead of writing a metrics() method that mimics what draw() does,
re-use the draw code with a null painter.

This has the additional benefit of fixing InsetSpecialChar logo width
with EB Garamond. I have to admit that I do not know why it was too
large with the old code, but the new code is shorter/better anyway.

This code removes logowidth(). metrics() is moved to a different
place, but only the logo cases are touched.

diff --git a/src/insets/InsetSpecialChar.cpp b/src/insets/InsetSpecialChar.cpp
index 57a1ceb390c174ded28f709ac2eb3fe46b2e8800..ec9daba0e9f9de69eccdea7b71a951ec52f93fab 100644 (file)
--- a/src/insets/InsetSpecialChar.cpp
+++ b/src/insets/InsetSpecialChar.cpp
@@ -24,6 +24,7 @@
 #include "texstream.h"
 
 #include "frontends/FontMetrics.h"
+#include "frontends/NullPainter.h"
 #include "frontends/Painter.h"
 
 #include "support/debug.h"
@@ -45,48 +46,6 @@ InsetSpecialChar::Kind InsetSpecialChar::kind() const
 }
 
 
-namespace {
-
-int logoWidth(FontInfo const & font, InsetSpecialChar::Kind kind) {
-       frontend::FontMetrics const & fm = theFontMetrics(font);
-       int const em = fm.em();
-       int width = 0;
-       // See drawlogo() below to understand what this does.
-       switch (kind) {
-       case InsetSpecialChar::PHRASE_LYX:
-               width = fm.width(from_ascii("L")) - em / 6
-                       + fm.width(from_ascii("Y")) - em / 8
-                       + fm.width(from_ascii("X"));
-               break;
-
-       case InsetSpecialChar::PHRASE_TEX:
-               width = fm.width(from_ascii("T")) - em / 6
-                       + fm.width(from_ascii("E")) - em / 8
-                       + fm.width(from_ascii("X"));
-               break;
-
-       case InsetSpecialChar::PHRASE_LATEX2E:
-               width = logoWidth(font, InsetSpecialChar::PHRASE_LATEX)
-                       + 3 * em / 20
-                       + fm.width(from_ascii("2") + char_type(0x03b5));
-               break;
-       case InsetSpecialChar::PHRASE_LATEX: {
-               FontInfo smaller = font;
-               smaller.decSize().decSize();
-               width = fm.width(from_ascii("L")) - 9 * em / 25
-                       + theFontMetrics(smaller).width(from_ascii("A")) - 3 * em / 20
-                       + logoWidth(font, InsetSpecialChar::PHRASE_TEX);
-               break;
-       }
-       default:
-               LYXERR0("No information for computing width of logo " << kind);
-       }
-
-       return width;
-}
-
-} // namespace
-
 docstring InsetSpecialChar::toolTip(BufferView const &, int, int) const
 {
        docstring message;
@@ -122,61 +81,6 @@ docstring InsetSpecialChar::toolTip(BufferView const &, int, int) const
 }
 
 
-void InsetSpecialChar::metrics(MetricsInfo & mi, Dimension & dim) const
-{
-       frontend::FontMetrics const & fm =
-               theFontMetrics(mi.base.font);
-       dim.asc = fm.maxAscent();
-       dim.des = 0;
-       dim.wid = 0;
-
-       docstring s;
-       switch (kind_) {
-               case ALLOWBREAK:
-                       dim.asc = fm.xHeight();
-                       dim.des = fm.descent('g');
-                       dim.wid = fm.em() / 8;
-                       break;
-               case LIGATURE_BREAK:
-                       s = from_ascii("|");
-                       break;
-               case END_OF_SENTENCE:
-                       s = from_ascii(".");
-                       break;
-               case LDOTS:
-                       s = from_ascii(". . .");
-                       break;
-               case MENU_SEPARATOR:
-                       // ▹  U+25B9 WHITE RIGHT-POINTING SMALL TRIANGLE
-                       // There is a \thinspace on each side of the triangle
-                       dim.wid = 2 * fm.em() / 6 + fm.width(char_type(0x25B9));
-                       break;
-               case HYPHENATION:
-                       dim.wid = fm.width(from_ascii("-"));
-                       if (dim.wid > 5)
-                               dim.wid -= 2; // to make it look shorter
-                       break;
-               case SLASH:
-                       s = from_ascii("/");
-                       dim.des = fm.descent(s[0]);
-                       break;
-               case NOBREAKDASH:
-                       s = from_ascii("-");
-                       break;
-               case PHRASE_LYX:
-               case PHRASE_TEX:
-               case PHRASE_LATEX2E:
-               case PHRASE_LATEX:
-                       dim.asc = fm.maxAscent();
-                       dim.des = fm.maxDescent();
-                       dim.wid = logoWidth(mi.base.font, kind_);
-                       break;
-       }
-       if (dim.wid == 0)
-               dim.wid = fm.width(s);
-}
-
-
 namespace {
 
 // helper function: draw text and update x.
@@ -258,6 +162,64 @@ void drawLogo(PainterInfo & pi, int & x, int const y, InsetSpecialChar::Kind kin
 
 } // namespace
 
+
+void InsetSpecialChar::metrics(MetricsInfo & mi, Dimension & dim) const
+{
+       frontend::FontMetrics const & fm =
+               theFontMetrics(mi.base.font);
+       dim.asc = fm.maxAscent();
+       dim.des = 0;
+       dim.wid = 0;
+
+       docstring s;
+       switch (kind_) {
+               case ALLOWBREAK:
+                       dim.asc = fm.xHeight();
+                       dim.des = fm.descent('g');
+                       dim.wid = fm.em() / 8;
+                       break;
+               case LIGATURE_BREAK:
+                       s = from_ascii("|");
+                       break;
+               case END_OF_SENTENCE:
+                       s = from_ascii(".");
+                       break;
+               case LDOTS:
+                       s = from_ascii(". . .");
+                       break;
+               case MENU_SEPARATOR:
+                       // ▹  U+25B9 WHITE RIGHT-POINTING SMALL TRIANGLE
+                       // There is a \thinspace on each side of the triangle
+                       dim.wid = 2 * fm.em() / 6 + fm.width(char_type(0x25B9));
+                       break;
+               case HYPHENATION:
+                       dim.wid = fm.width(from_ascii("-"));
+                       if (dim.wid > 5)
+                               dim.wid -= 2; // to make it look shorter
+                       break;
+               case SLASH:
+                       s = from_ascii("/");
+                       dim.des = fm.descent(s[0]);
+                       break;
+               case NOBREAKDASH:
+                       s = from_ascii("-");
+                       break;
+               case PHRASE_LYX:
+               case PHRASE_TEX:
+               case PHRASE_LATEX2E:
+               case PHRASE_LATEX:
+                       dim.asc = fm.maxAscent();
+                       dim.des = fm.maxDescent();
+                       frontend::NullPainter np;
+                       PainterInfo pi(mi.base.bv, np);
+                       drawLogo(pi, dim.wid, 0, kind_);
+                       break;
+       }
+       if (dim.wid == 0)
+               dim.wid = fm.width(s);
+}
+
+
 void InsetSpecialChar::draw(PainterInfo & pi, int x, int y) const
 {
        FontInfo font = pi.base.font;