layout/style/nsStyleUtil.h

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  37 #ifndef nsStyleUtil_h___
  38 #define nsStyleUtil_h___
  39
  40 #include "nsCoord.h"
  41 #include "nsPresContext.h"
  42 #include "nsILinkHandler.h" // for nsLinkState
  43
  44 struct nsStyleBackground;
  45
  46 enum nsFontSizeType {
  47   eFontSize_HTML = 1,
  48   eFontSize_CSS = 2
  49 };
  50
  51
  52 // Style utility functions
  53 class nsStyleUtil {
  54 public:
  55
  56   static float GetScalingFactor(PRInt32 aScaler);
  57
  58   static nscoord CalcFontPointSize(PRInt32 aHTMLSize, PRInt32 aBasePointSize,
  59                                    float aScalingFactor, nsPresContext* aPresContext,
  60                                    nsFontSizeType aFontSizeType = eFontSize_HTML);
  61
  62   static nscoord FindNextSmallerFontSize(nscoord aFontSize, PRInt32 aBasePointSize,
  63                                          float aScalingFactor, nsPresContext* aPresContext,
  64                                          nsFontSizeType aFontSizeType = eFontSize_HTML);
  65
  66   static nscoord FindNextLargerFontSize(nscoord aFontSize, PRInt32 aBasePointSize,
  67                                         float aScalingFactor, nsPresContext* aPresContext,
  68                                         nsFontSizeType aFontSizeType = eFontSize_HTML);
  69
  70   static PRInt32 ConstrainFontWeight(PRInt32 aWeight);
  71
  72   // If aForStyling is false, don't add the link to the document's
  73   // list of links to notify on history changes.
  74   static PRBool IsHTMLLink(nsIContent *aContent, nsIAtom *aTag,
  75                            nsILinkHandler *aLinkHandler,
  76                            PRBool aForStyling,
  77                            nsLinkState *aState);
  78   static PRBool IsLink(nsIContent *aContent, nsILinkHandler *aLinkHandler,
  79                        PRBool aForStyling, nsLinkState *aState);
  80
  81  static PRBool DashMatchCompare(const nsAString& aAttributeValue,
  82                                 const nsAString& aSelectorValue,
  83                                 const nsStringComparator& aComparator);
  84
  85   static void EscapeCSSString(const nsString& aString, nsAString& aReturn);
  86
  87   /*
  88    * Convert an author-provided floating point number to an integer (0
  89    * ... 255) appropriate for use in the alpha component of a color.
  90    */
  91   static PRUint8 FloatToColorComponent(float aAlpha)
  92   {
  93     NS_ASSERTION(0.0 <= aAlpha && aAlpha <= 1.0, "out of range");
  94     return NSToIntRound(aAlpha * 255);
  95   }
  96
  97   /*
  98    * Convert the alpha component of an nscolor (0 ... 255) to the
  99    * floating point number with the least accurate *decimal*
 100    * representation that is converted to that color.
 101    *
 102    * Should be used only by serialization code.
 103    */
 104   static float ColorComponentToFloat(PRUint8 aAlpha);
 105
 106   /*
 107    * Does this child count as significant for selector matching?
 108    */
 109   static PRBool IsSignificantChild(nsIContent* aChild,
 110                                    PRBool aTextIsSignificant,
 111                                    PRBool aWhitespaceIsSignificant);
 112 };
 113
 114
 115 #endif /* nsStyleUtil_h___ */