Initial check-in of new X/GTK font code. Improved font-weight "bolder"

and "lighter", more accurate font-size (max ascent and max descent),
better speed.
However, ifdeffed for now to try on various platforms.

gfx/src/gtk/nsFontMetricsGTK.h

@@ -30,6 +30,39 @@
 #include <gdk/gdk.h>
 #include <gdk/gdkx.h>
 
+#undef FONT_SWITCHING
+#ifdef FONT_SWITCHING
+
+#ifdef ADD_GLYPH
+#undef ADD_GLYPH
+#endif
+#define ADD_GLYPH(map, g) (map)[(g) >> 3] |= (1 << ((g) & 7))
+
+#ifdef FONT_HAS_GLYPH
+#undef FONT_HAS_GLYPH
+#endif
+#define FONT_HAS_GLYPH(map, g) (((map)[(g) >> 3] >> ((g) & 7)) & 1)
+
+typedef struct nsFontCharSetInfo nsFontCharSetInfo;
+
+typedef gint (*nsFontCharSetConverter)(nsFontCharSetInfo* aSelf,
+  const PRUnichar* aSrcBuf, PRUint32 aSrcLen, PRUint8* aDestBuf,
+  PRUint32 aDestLen);
+
+typedef struct nsFontGTK
+{
+  GdkFont*               mFont;
+  PRUint8*               mMap;
+  nsFontCharSetInfo*     mCharSetInfo;
+  char*                  mName;
+} nsFontGTK;
+
+struct nsFontCharSet;
+struct nsFontFamily;
+typedef struct nsFontSearch nsFontSearch;
+
+#endif /* FONT_SWITCHING */
+
 class nsFontMetricsGTK : public nsIFontMetrics
 {
 public:
@@ -57,6 +90,27 @@ public:
   NS_IMETHOD  GetFont(const nsFont *&aFont);
   NS_IMETHOD  GetFontHandle(nsFontHandle &aHandle);
 
+#ifdef FONT_SWITCHING
+
+  nsFontGTK*  FindFont(PRUnichar aChar);
+  static gint GetWidth(GdkFont* aFont, nsFontCharSetInfo* aInfo,
+                       const PRUnichar* aString, PRUint32 aLength);
+  static void InitFonts(void);
+
+  friend void TryCharSet(nsFontSearch* aSearch, nsFontCharSet* aCharSet);
+  friend void TryFamily(nsFontSearch* aSearch, nsFontFamily* aFamily);
+
+  nsFontGTK   *mLoadedFonts;
+  PRUint16    mLoadedFontsAlloc;
+  PRUint16    mLoadedFontsCount;
+
+  nsString    *mFonts;
+  PRUint16    mFontsAlloc;
+  PRUint16    mFontsCount;
+  PRUint16    mFontsIndex;
+
+#endif /* FONT_SWITCHING */
+
 protected:
   char *PickAppropriateSize(char **names, XFontStruct *fonts, int cnt, nscoord desired);
   void RealizeFont();
@@ -79,6 +133,14 @@ protected:
   nscoord             mStrikeoutOffset;
   nscoord             mUnderlineSize;
   nscoord             mUnderlineOffset;
+
+#ifdef FONT_SWITCHING
+
+  PRUint16            mPixelSize;
+  PRUint8             mStretchIndex;
+  PRUint8             mStyleIndex;
+
+#endif /* FONT_SWITCHING */
 };
 
 #endif

gfx/src/gtk/nsRenderingContextGTK.cpp

@@ -17,6 +17,7 @@
  */
 
 #include <gtk/gtk.h>
+#include "nsFontMetricsGTK.h"
 #include "nsRenderingContextGTK.h"
 #include "nsRegionGTK.h"
 #include "nsGfxCIID.h"
@@ -829,6 +830,23 @@ NS_IMETHODIMP nsRenderingContextGTK::FillArc(nscoord aX, nscoord aY,
   return NS_OK;
 }
 
+#ifdef FONT_SWITCHING
+
+NS_IMETHODIMP
+nsRenderingContextGTK::GetWidth(char aC, nscoord &aWidth)
+{
+  return GetWidth(&aC, 1, aWidth);
+}
+
+NS_IMETHODIMP
+nsRenderingContextGTK::GetWidth(PRUnichar aC, nscoord& aWidth,
+                                PRInt32* aFontID)
+{
+  return GetWidth(&aC, 1, aWidth, aFontID);
+}
+
+#else /* FONT_SWITCHING */
+
 NS_IMETHODIMP
 nsRenderingContextGTK::GetWidth(char aC, nscoord &aWidth)
 {
@@ -848,6 +866,8 @@ nsRenderingContextGTK::GetWidth(PRUnichar aC, nscoord& aWidth,
   return NS_OK;
 }
 
+#endif /* FONT_SWITCHING */
+
 NS_IMETHODIMP
 nsRenderingContextGTK::GetWidth(const nsString& aString,
                                 nscoord& aWidth, PRInt32* aFontID)
@@ -861,6 +881,89 @@ nsRenderingContextGTK::GetWidth(const char* aString, nscoord& aWidth)
   return GetWidth(aString, strlen(aString), aWidth);
 }
 
+#ifdef FONT_SWITCHING
+
+NS_IMETHODIMP
+nsRenderingContextGTK::GetWidth(const char* aString, PRUint32 aLength,
+                                nscoord& aWidth)
+{
+  if (0 == aLength) {
+    aWidth = 0;
+  }
+  else {
+    g_return_val_if_fail(aString != NULL, NS_ERROR_FAILURE);
+    gint rawWidth = gdk_text_width (mCurrentFont, aString, aLength);
+    aWidth = NSToCoordRound(rawWidth * mP2T);
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsRenderingContextGTK::GetWidth(const PRUnichar* aString, PRUint32 aLength,
+                                nscoord& aWidth, PRInt32* aFontID)
+{
+  if (0 == aLength) {
+    aWidth = 0;
+  }
+  else {
+    g_return_val_if_fail(aString != NULL, NS_ERROR_FAILURE);
+
+    nsFontMetricsGTK* metrics = (nsFontMetricsGTK*) mFontMetrics;
+    GdkFont* prevFont = nsnull;
+    nsFontCharSetInfo* prevCharSetInfo = nsnull;
+    gint rawWidth = 0;
+    PRUint32 start = 0;
+    PRUint32 i;
+    for (i = 0; i < aLength; i++) {
+      PRUnichar c = aString[i];
+      GdkFont* currFont = nsnull;
+      nsFontCharSetInfo* currCharSetInfo = nsnull;
+      nsFontGTK* font = metrics->mLoadedFonts;
+      nsFontGTK* end = &metrics->mLoadedFonts[metrics->mLoadedFontsCount];
+      while (font < end) {
+        if (FONT_HAS_GLYPH(font->mMap, c)) {
+	  currFont = font->mFont;
+	  currCharSetInfo = font->mCharSetInfo;
+	  goto FoundFont; // for speed -- avoid "if" statement
+	}
+	font++;
+      }
+      font = metrics->FindFont(c);
+      currFont = font->mFont;
+      currCharSetInfo = font->mCharSetInfo;
+FoundFont:
+      // XXX avoid this test by duplicating code -- erik
+      if (prevFont) {
+	if (currFont != prevFont) {
+          rawWidth += nsFontMetricsGTK::GetWidth(prevFont, prevCharSetInfo,
+	    &aString[start], i - start);
+	  prevFont = currFont;
+	  prevCharSetInfo = currCharSetInfo;
+	  start = i;
+	}
+      }
+      else {
+        prevFont = currFont;
+	prevCharSetInfo = currCharSetInfo;
+	start = i;
+      }
+    }
+
+    if (prevFont) {
+      rawWidth += nsFontMetricsGTK::GetWidth(prevFont, prevCharSetInfo,
+        &aString[start], i - start);
+    }
+
+    aWidth = NSToCoordRound(rawWidth * mP2T);
+  }
+  if (nsnull != aFontID)
+    *aFontID = 0;
+
+  return NS_OK;
+}
+
+#else /* FONT_SWITCHING */
+
 NS_IMETHODIMP
 nsRenderingContextGTK::GetWidth(const char* aString, PRUint32 aLength,
                                 nscoord& aWidth)
@@ -915,6 +1018,8 @@ nsRenderingContextGTK::GetWidth(const PRUnichar* aString, PRUint32 aLength,
   return NS_OK;
 }
 
+#endif /* FONT_SWITCHING */
+
 NS_IMETHODIMP
 nsRenderingContextGTK::DrawString(const char *aString, PRUint32 aLength,
                                   nscoord aX, nscoord aY,