Simplified and improved the glyph margin computation and usage

include/osgText/Font

@@ -107,23 +107,6 @@ public:
      *  return true on success, return false when not supported.*/
     virtual bool getVerticalSize(float& ascender, float& descender) const { return _implementation ? _implementation->getVerticalSize(ascender, descender) : false; }
 
-    /** Set the margin around each glyph,
-      * to ensure that texture filtering doesn't bleed adjacent glyph's into each other.
-      * Default margin is 1 texels.*/
-    void setGlyphImageMargin(unsigned int margin);
-    unsigned int getGlyphImageMargin() const;
-
-    /** Set the margin ratio around each glyph, relative to the glyph's size.
-      * to ensure that texture filtering doesn't bleed adjacent glyph's into each other.
-      * Default margin is 0.05.*/
-    void setGlyphImageMarginRatio(float margin);
-    float getGlyphImageMarginRatio() const;
-
-    /** Set the interval that glyph positions are clamped to.
-      * Default interval is 1 texels.*/
-    void setGlyphInterval(int interval);
-    int getGlyphInterval() const;
-
 
     void setGyphTextureFeatures(GlyphTexture::Features features) { _glyphTextureFeatures = features; }
     GlyphTexture::Features getGlyphTextureFeatures() const { return _glyphTextureFeatures; }
@@ -202,9 +185,7 @@ protected:
 
     // current active size of font
     FontResolution                  _fontSize;
-    unsigned int                    _margin;
-    float                           _marginRatio;
-    int                             _glyphInterval;
+
     GlyphTexture::Features          _glyphTextureFeatures;
 
     unsigned int                    _textureWidthHint;

include/osgText/Glyph

@@ -93,6 +93,9 @@ public:
     void setMaxTexCoord(const osg::Vec2& coord);
     const osg::Vec2& getMaxTexCoord() const;
 
+    void setTexelMargin(float margin) { _texelMargin = margin; }
+    float getTexelMargin() const { return _texelMargin; }
+
 protected:
 
     virtual ~Glyph();
@@ -116,6 +119,7 @@ protected:
     int                         _texturePosY;
     osg::Vec2                   _minTexCoord;
     osg::Vec2                   _maxTexCoord;
+    float                       _texelMargin;
 
     typedef osg::buffered_value<GLuint> GLObjectList;
     mutable GLObjectList _globjList;
@@ -256,16 +260,6 @@ public:
     /** return -1 if *this < *rhs, 0 if *this==*rhs, 1 if *this>*rhs.*/
     virtual int compare(const osg::StateAttribute& rhs) const;
 
-    /** Set the margin around each glyph, to ensure that texture filtering doesn't bleed adjacent glyph's into each other.*/
-    void setGlyphImageMargin(unsigned int margin) { _margin = margin; }
-    unsigned int getGlyphImageMargin() const { return _margin; }
-
-    void setGlyphImageMarginRatio(float margin) { _marginRatio = margin; }
-    float getGlyphImageMarginRatio() const { return _marginRatio; }
-
-    void setGlyphInterval(int interval) { _interval = interval; }
-    int getGlyphInterval() const { return _interval; }
-
     enum Features
     {
         GREYSCALE,
@@ -277,6 +271,10 @@ public:
     void setGlyphTextureFeatures(Features features) { _glyphTextureFeatures = features; }
     Features getGlyphTextureFeatures() const { return _glyphTextureFeatures; }
 
+
+    int getEffectMargin(const Glyph* glyph);
+    int getTexelMargin(const Glyph* glyph);
+
     bool getSpaceForGlyph(Glyph* glyph, int& posX, int& posY);
 
     void addGlyph(Glyph* glyph,int posX, int posY);
@@ -296,12 +294,6 @@ protected:
 
     void copyGlyphImage(Glyph* glyph);
 
-
-    // parameter used to compute the size and position of empty space
-    // in the texture which could accommodate new glyphs.
-    int         _margin;
-    float       _marginRatio;
-    int         _interval;
     Features    _glyphTextureFeatures;
 
     int         _usedY;