Clamp final font size (after font-size-adjust) to a reasonable value. b=383473 r+sr=vladimir

gfx/thebes/public/gfxFont.h

@@ -49,6 +49,7 @@
 #include "gfxSkipChars.h"
 #include "gfxRect.h"
 #include "nsExpirationTracker.h"
+#include "nsMathUtils.h"
 
 class gfxContext;
 class gfxTextRun;
@@ -64,6 +65,8 @@ typedef struct _cairo cairo_t;
 #define FONT_WEIGHT_NORMAL             400
 #define FONT_WEIGHT_BOLD               700
 
+#define FONT_MAX_SIZE                  2000.0
+
 struct THEBES_API gfxFontStyle {
     gfxFontStyle(PRUint8 aStyle, PRUint16 aWeight, gfxFloat aSize,
                  const nsACString& aLangGroup,
@@ -102,6 +105,14 @@ struct THEBES_API gfxFontStyle {
     // needs to be done.
     float sizeAdjust;
 
+    // Return the final adjusted font size for the given aspect ratio.
+    // Not meant to be called when sizeAdjust = 0.
+    gfxFloat GetAdjustedSize(gfxFloat aspect) const {
+        NS_ASSERTION(sizeAdjust != 0.0, "Not meant to be called when sizeAdjust = 0");
+        gfxFloat adjustedSize = PR_MAX(NS_round(size*(sizeAdjust/aspect)), 1.0);
+        return PR_MIN(adjustedSize, FONT_MAX_SIZE);
+    }
+
     PLDHashNumber Hash() const {
         return ((style + (systemFont << 7) + (familyNameQuirks << 8) +
             (weight << 9)) + PRUint32(size*1000) + PRUint32(sizeAdjust*1000)) ^

gfx/thebes/src/gfxAtsuiFonts.cpp

@@ -156,8 +156,7 @@ gfxAtsuiFont::InitMetrics(ATSUFontID aFontID, ATSFontRef aFontRef)
     if (mAdjustedSize == 0) {
         if (GetStyle()->sizeAdjust != 0) {
             gfxFloat aspect = mMetrics.xHeight / size;
-            mAdjustedSize =
-                PR_MAX(ROUND(size * (GetStyle()->sizeAdjust / aspect)), 1.0f);
+            mAdjustedSize = GetStyle()->GetAdjustedSize(aspect);
             InitMetrics(aFontID, aFontRef);
             return;
         }

gfx/thebes/src/gfxFont.cpp

@@ -560,15 +560,13 @@ gfxFontStyle::gfxFontStyle(PRUint8 aStyle, PRUint16 aWeight, gfxFloat aSize,
     familyNameQuirks(aFamilyNameQuirks), weight(aWeight),
     size(aSize), langGroup(aLangGroup), sizeAdjust(aSizeAdjust)
 {
-    static const gfxFloat kMaxFontSize = 2000.0;
-
     if (weight > 900)
         weight = 900;
     if (weight < 100)
         weight = 100;
 
-    if (size >= kMaxFontSize) {
-        size = kMaxFontSize;
+    if (size >= FONT_MAX_SIZE) {
+        size = FONT_MAX_SIZE;
         sizeAdjust = 0.0;
     } else if (size < 0.0) {
         NS_WARNING("negative font size");

gfx/thebes/src/gfxPangoFonts.cpp

@@ -412,8 +412,7 @@ gfxPangoFont::RealizeFont(PRBool force)
     gfxSize isz, lsz;
     GetCharSize('x', isz, lsz);
     gfxFloat aspect = isz.height / GetStyle()->size;
-    mAdjustedSize =
-        PR_MAX(NS_round(GetStyle()->size*(GetStyle()->sizeAdjust/aspect)), 1.0);
+    mAdjustedSize = GetStyle()->GetAdjustedSize(aspect);
     RealizeFont(PR_TRUE);
 }
 

gfx/thebes/src/gfxWindowsFonts.cpp

@@ -238,8 +238,7 @@ gfxWindowsFont::MakeHFONT()
         Metrics *oldMetrics = mMetrics;
         ComputeMetrics();
         gfxFloat aspect = mMetrics->xHeight / mMetrics->emHeight;
-        mAdjustedSize =
-            PR_MAX(ROUND(GetStyle()->size * (GetStyle()->sizeAdjust / aspect)), 1.0f);
+        mAdjustedSize = GetStyle()->GetAdjustedSize(aspect);
 
         if (mMetrics != oldMetrics) {
             delete mMetrics;