Package gov.nasa.worldwind.render

Class MultiLineTextRenderer

  • public class MultiLineTextRenderer
extends java.lang.Object
    Multi line, rectangle bound text renderer with (very) minimal html support.

    The MultiLineTextRenderer (MLTR) handles wrapping, measuring and drawing of multiline text strings using Sun's JOGL TextRenderer.

    A multiline text string is a character string containing new line characters in between lines.

    MLTR can handle both regular text with new line separators and a very minimal implementation of HTML. Each type of text has its own methods though.

    Usage:

    Instantiation:

    The MLTR needs a Font or a TextRenderer to be instantiated. This will be the font used for text drawing, wrapping and measuring. For HTML methods this font will be considered as the document default font. 

     Font font = Font.decode("Arial-PLAIN-12");
 MultiLineTextRenderer mltr = new MultiLineTextRenderer(font);
    or 
     TextRenderer tr = new TextRenderer(Font.decode("Arial-PLAIN-10"));
 MultiLineTextRenderer mltr = new MultiLineTextRenderer(tr);

    Drawing regular text:

     String text = "Line one.\nLine two.\nLine three...";
 int x = 10;             // Upper left corner of text rectangle.
 int y = 200;            // Origin at bottom left of screen.
 int lineHeight = 14;    // Line height in pixels.
 Color color = Color.RED;
 mltr.setTextColor(color);
 mltr.getTextRenderer().begin3DRendering();
 mltr.draw(text, x, y, lineHeight);
 mltr.getTextRenderer().end3DRendering();

    Wrapping text to fit inside a width and optionally a height

    The MLTR wrap method will insert new line characters inside the text so that it fits a given width in pixels.

    If a height dimension above zero is specified too, the text will be truncated if needed, and a continuation string will be appended to the last line. The continuation string can be set with mltr.setContinuationString(); 

     // Fit inside 300 pixels, no height constraint
 String wrappedText = mltr.wrap(text, new Dimension(300, 0));
 // Fit inside 300x400 pixels, text may be truncated
 String wrappedText = mltr.wrap(text, new Dimension(300, 400));

    Measuring text

     Rectangle2D textBounds = mltr.getBounds(text);

    The textBounds rectangle returned contains the width and height of the text as it would be drawn with the current font.

    Note that textBounds.minX is the number of lines found and textBounds.minY is the maximum line height for the font used. This value can be safely used as the lineHeight argument when drawing - or can even be ommited after a getBounds: draw(text, x, y); ...

    HTML support

    Supported tags are:

    • <p></p>, <br> <br />
    • <b></b>
    • <i></i>
    • <a href="..."></a>
    • <font color="#ffffff"></font>
    ...

    See AbstractAnnotation.drawAnnotation() for more usage details.

    • Field Detail

      • lineSpacing

        protected int lineSpacing

      • lineHeight

        protected int lineHeight

      • textAlign

        protected java.lang.String textAlign

      • continuationString

        protected java.lang.String continuationString

      • textColor

        protected java.awt.Color textColor

      • backColor

        protected java.awt.Color backColor

      • linkColor

        protected java.awt.Color linkColor

      • isPicking

        protected boolean isPicking

      • pickObject

        protected java.lang.Object pickObject

      • pickPosition

        protected Position pickPosition

      • SGMLPattern

        protected static java.util.regex.Pattern SGMLPattern

      • SGMLOrSpacePattern

        protected static java.util.regex.Pattern SGMLOrSpacePattern

    • Constructor Detail

      • MultiLineTextRenderer

        public MultiLineTextRenderer​(TextRenderer textRenderer)

      • MultiLineTextRenderer

        public MultiLineTextRenderer​(java.awt.Font font)

    • Method Detail

      • getTextRenderer

        public TextRenderer getTextRenderer()
        Get the current TextRenderer.
        Returns:
        the current TextRenderer.

      • getLineSpacing

        public int getLineSpacing()
        Get the current line spacing height in pixels.
        Returns:
        the current line spacing height in pixels.

      • setLineSpacing

        public void setLineSpacing​(int height)
        Set the current line spacing height in pixels.
        Parameters:
        height - the line spacing height in pixels.

      • getLineHeight

        public int getLineHeight()
        Get the current line height in pixels.
        Returns:
        the current line height in pixels.

      • setLineHeight

        public void setLineHeight​(int height)
        Set the current line height in pixels.
        Parameters:
        height - the current line height in pixels.

      • getTextAlign

        public java.lang.String getTextAlign()
        Get the current text alignment. Can be one of AVKey.LEFT the default, AVKey.CENTER or AVKey.RIGHT.
        Returns:
        the current text alignment.

      • setTextAlign

        public void setTextAlign​(java.lang.String align)
        Set the current text alignment. Can be one of AVKey.LEFT the default, AVKey.CENTER or AVKey.RIGHT.
        Parameters:
        align - the current text alignment.

      • getTextColor

        public java.awt.Color getTextColor()
        Get the current text color.
        Returns:
        the current text color.

      • setTextColor

        public void setTextColor​(java.awt.Color color)
        Set the text renderer color.
        Parameters:
        color - the color to use when drawing text.

      • getBackColor

        public java.awt.Color getBackColor()
        Get the background color used for EFFECT_SHADOW and EFFECT_OUTLINE.
        Returns:
        the current background color used when drawing shadow or outline..

      • setBackColor

        public void setBackColor​(java.awt.Color color)
        Set the background color used for EFFECT_SHADOW and EFFECT_OUTLINE.
        Parameters:
        color - the color to use when drawing shadow or outline.

      • getLinkColor

        public java.awt.Color getLinkColor()
        Get the current link color.
        Returns:
        the current link color.

      • setLinkColor

        public void setLinkColor​(java.awt.Color color)
        Set the link color.
        Parameters:
        color - the color to use when drawing hyperlinks.

      • setContinuationString

        public void setContinuationString​(java.lang.String s)
        Set the character string appended at the end of text truncated during a wrap operation when exceeding the given height limit.
        Parameters:
        s - the continuation character string.

      • getMaxLineHeight

        public double getMaxLineHeight​(TextRenderer tr)
        Get the maximum line height for the given text renderer.
        Parameters:
        tr - the TextRenderer.
        Returns:
        the maximum line height.

      • getBounds

        public java.awt.Rectangle getBounds​(java.lang.String text)
        Returns the bounding rectangle for a multi-line string.

        Note that the X component of the rectangle is the number of lines found in the text and the Y component of the rectangle is the max line height encountered.

        Note too that this method will automatically set the current line height to the max height found.

        Parameters:
        text - the multi-line text to evaluate.
        Returns:
        the bounding rectangle for the string.

      • draw

        public void draw​(java.lang.String text,
                 int x,
                 int y)
        Draw a multi-line text string with bounding rectangle top starting at the y position. Depending on the current textAlign, the x position is either the rectangle left side, middle or right side.

        Uses the current line height.

        Parameters:
        text - the multi-line text to draw.
        x - the x position for top left corner of text rectangle.
        y - the y position for top left corner of the text rectangle.

      • draw

        public void draw​(java.lang.String text,
                 int x,
                 int y,
                 java.lang.String effect)
        Draw a multi-line text string with bounding rectangle top starting at the y position. Depending on the current textAlign, the x position is either the rectangle left side, middle or right side.

        Uses the current line height and the given effect.

        Parameters:
        text - the multi-line text to draw.
        x - the x position for top left corner of text rectangle.
        y - the y position for top left corner of the text rectangle.
        effect - the effect to use for the text rendering. Can be one of EFFECT_NONE, EFFECT_SHADOW or EFFECT_OUTLINE.

      • draw

        public void draw​(java.lang.String text,
                 int x,
                 int y,
                 int textLineHeight,
                 java.lang.String effect)
        Draw a multi-line text string with bounding rectangle top starting at the y position. Depending on the current textAlign, the x position is either the rectangle left side, middle or right side.

        Uses the given line height and effect.

        Parameters:
        text - the multi-line text to draw.
        x - the x position for top left corner of text rectangle.
        y - the y position for top left corner of the text rectangle.
        textLineHeight - the line height in pixels.
        effect - the effect to use for the text rendering. Can be one of EFFECT_NONE, EFFECT_SHADOW or EFFECT_OUTLINE.

      • draw

        public void draw​(java.lang.String text,
                 int x,
                 int y,
                 int textLineHeight)
        Draw a multi-line text string with bounding rectangle top starting at the y position. Depending on the current textAlign, the x position is either the rectangle left side, middle or right side.

        Uses the given line height.

        Parameters:
        text - the multi-line text to draw.
        x - the x position for top left corner of text rectangle.
        y - the y position for top left corner of the text rectangle.
        textLineHeight - the line height in pixels.

      • pick

        public void pick​(java.lang.String text,
                 int x,
                 int y,
                 int textLineHeight,
                 DrawContext dc,
                 PickSupport pickSupport,
                 java.lang.Object refObject,
                 Position refPosition)
        Draw text with unique colors word bounding rectangles and add each as a pickable object to the provided PickSupport instance.
        Parameters:
        text - the multi-line text to draw.
        x - the x position for top left corner of text rectangle.
        y - the y position for top left corner of the text rectangle.
        textLineHeight - the line height in pixels.
        dc - the current DrawContext.
        pickSupport - the PickSupport instance to be used.
        refObject - the user reference object associated with every picked word.
        refPosition - the user reference Position associated with every picked word.

      • drawLineWithUniqueColors

        protected void drawLineWithUniqueColors​(java.lang.String text,
                                        int x,
                                        int y,
                                        DrawContext dc,
                                        PickSupport pickSupport,
                                        java.lang.Object refObject,
                                        Position refPosition)

      • wrap

        public java.lang.String wrap​(java.lang.String text,
                             int width,
                             int height)
        Add 'new line' characters inside a string so that it's bounding rectangle tries not to exceed the given dimension width.

        If the dimension height is more than zero, the text will be truncated accordingly and the continuation string will be appended to the last line.

        Note that words will not be split and at least one word will be used per line so the longest word defines the final width of the bounding rectangle. Each line is trimmed of leading and trailing spaces.

        Parameters:
        text - the text string to wrap
        width - the maximum width in pixels the text can occupy.
        height - if not zero, the maximum height in pixels the text can occupy.
        Returns:
        the wrapped string.

      • wrapLine

        protected java.lang.String wrapLine​(java.lang.String text,
                                    int width)

      • containsHTML

        public static boolean containsHTML​(java.lang.String text)
        Return true if the text contains some sgml tags.
        Parameters:
        text - The text string to evaluate.
        Returns:
        true if the string contains sgml or html tags

      • processLineBreaksHTML

        public static java.lang.String processLineBreaksHTML​(java.lang.String text)
        Remove new line characters then replace BR and P tags with appropriate new lines.
        Parameters:
        text - The html text string to process.
        Returns:
        The processed text string.

      • removeTagsHTML

        public static java.lang.String removeTagsHTML​(java.lang.String text)
        Remove all HTML tags from a text string.
        Parameters:
        text - the string to filter.
        Returns:
        the filtered string.

      • getAttributeFromTagHTML

        public static java.lang.String getAttributeFromTagHTML​(java.lang.String text,
                                                       java.lang.String attributeName)
        Extract an attribute value from a HTML tag string. The attribute is expected to be formed on the pattern: name="...". Other variants will likely fail.
        Parameters:
        text - the HTML tage string.
        attributeName - the attribute name.
        Returns:
        the attribute value found. Null if empty or not found.

      • getBoundsHTML

        public java.awt.Rectangle getBoundsHTML​(java.lang.String text,
                                        TextRendererCache renderers)
        Returns the bounding rectangle for a multi-line html string.
        Parameters:
        text - the multi-line html text to evaluate.
        renderers - a TextRendererCache instance.
        Returns:
        the bounding rectangle for the rendered text.

      • wrapHTML

        public java.lang.String wrapHTML​(java.lang.String text,
                                 double width,
                                 double height,
                                 TextRendererCache renderers)
        Add 'new line' characters inside an html text string so that it's bounding rectangle tries not to exceed the given dimension width.

        If the dimension height is more than zero, the text will be truncated accordingly and the continuation string will be appended to the last line.

        Note that words will not be split and at least one word will be used per line so the longest word defines the final width of the bounding rectangle. Each line is trimmed of leading and trailing spaces.

        Parameters:
        text - the html text string to wrap
        width - the maximum width in pixels one text line can occupy.
        height - if not zero, the maximum height the text can occupy.
        renderers - a TextRendererCache instance.
        Returns:
        the wrapped html string

      • pickHTML

        public void pickHTML​(java.lang.String text,
                     int x,
                     int y,
                     TextRendererCache renderers,
                     DrawContext dc,
                     PickSupport pickSupport,
                     java.lang.Object refObject,
                     Position refPosition)
        Draw text with unique colors word bounding rectangles and add each as a pickable object to the provided PickSupport instance.
        Parameters:
        text - the multi-line text to draw.
        x - the x position for top left corner of text rectangle.
        y - the y position for top left corner of the text rectangle.
        renderers - a TextRendererCache instance.
        dc - the current DrawContext.
        pickSupport - the PickSupport instance to be used.
        refObject - the user reference object associated with every picked word.
        refPosition - the user reference Position associated with every picked word.

      • drawHTML

        public void drawHTML​(java.lang.String text,
                     double x,
                     double y,
                     TextRendererCache renderers)
        Draw a multi-line html text string with bounding rectangle top starting at the y position. The x position is eiher the rectangle left side, middle or right side depending on the current text alignement.
        Parameters:
        text - the multi-line text to draw
        x - the x position for top left corner of text rectangle
        y - the y position for top left corner of the text rectangle
        renderers - a TextRendererCache instance.

      • pickWordPartHTML

        protected void pickWordPartHTML​(java.lang.String word,
                                double x,
                                double y,
                                java.awt.geom.Rectangle2D partBounds,
                                MultiLineTextRenderer.DrawState ds,
                                boolean expandStart)

      • pickWord

        protected void pickWord​(java.lang.String word,
                        java.lang.String hyperlink,
                        double drawX,
                        double drawY,
                        java.awt.geom.Rectangle2D wordBounds,
                        DrawContext dc,
                        PickSupport pickSupport,
                        java.lang.Object refObject,
                        Position refPosition)

      • drawFilledRectangle

        protected void drawFilledRectangle​(DrawContext dc,
                                   double x,
                                   double y,
                                   double width,
                                   double height)