Package com.luciad.view.lightspeed.util.opengl.texturefont

Class TLspTextureFont

java.lang.Object
com.luciad.view.lightspeed.services.glcache.ALspGLResource
com.luciad.view.lightspeed.util.opengl.texturefont.TLspTextureFont
public class TLspTextureFont extends ALspGLResource
Utility class for drawing text to a ILcdGLDrawable using a "texture font". A texture font is an image that contains all ASCII characters, allowing text to be drawn as a strip of texture-mapped quadrilaterals. This typically offers significantly better performance than other text rendering approaches.
Since:
2012.0

  • Constructor Details

    • TLspTextureFont

      public TLspTextureFont(Font aFont)
      Creates a painter for the specified font. By default, the font color is white and the halo effect is off.
      Parameters:
      aFont - an AWT font

    • TLspTextureFont

      public TLspTextureFont(Font aFont, Color aTextColor)
      Creates a painter for the specified font and color. By default, the halo effect is off.
      Parameters:
      aFont - an AWT font
      aTextColor - the font color

    • TLspTextureFont

      public TLspTextureFont(Font aFont, Color aTextColor, Color aHaloColor)
      Creates a painter for the specified font and color, and with a halo in the specified color.
      Parameters:
      aFont - an AWT font
      aTextColor - the font color
      aHaloColor - the halo color

  • Method Details

    • getFont

      public Font getFont()
      Returns the current font.
      Returns:
      the current font
      See Also:

    • setFont

      public void setFont(Font aFont)
      Sets the font to be used for text rendering. If this property is changed, a new texture font image will be generated the next time the painter is used, which is a costly operation. Applications should therefore avoid calling this method very frequently.
      Parameters:
      aFont - the new font to be used

    • getTextColor

      public Color getTextColor()
      Returns the current text color.
      Returns:
      the current text color
      See Also:

    • setTextColor

      public void setTextColor(Color aTextColor)
      Sets the color to be used for text rendering. If this property is changed, a new texture font image will be generated the next time the painter is used, which is a costly operation. Applications should therefore avoid calling this method very frequently.
      Parameters:
      aTextColor - the new text color to be used

    • getHaloColor

      public Color getHaloColor()
      Returns the current halo color.
      Returns:
      the current halo color
      See Also:

    • setHaloColor

      public void setHaloColor(Color aHaloColor)
      Sets the color to be used for halos around rendered text. If this property is changed, a new texture font image will be generated the next time the painter is used, which is a costly operation. Applications should therefore avoid calling this method very frequently.
      Parameters:
      aHaloColor - the new halo color to be used

    • isHaloEnabled

      public boolean isHaloEnabled()
      Returns whether or not the halo effect is on.
      Returns:
      whether or not the halo effect is on
      See Also:

    • setHaloEnabled

      public void setHaloEnabled(boolean aHaloEnabled)
      Toggles the use of a halo effect around rendered text. A halo is an outline of constant width around the text, which ensures that the text is clearly visible on all backgrounds. If this property is changed, a new texture font image will be generated the next time the painter is used, which is a costly operation. Applications should therefore avoid calling this method very frequently.
      Parameters:
      aHaloEnabled - specifies whether halos should be enabled or disabled

    • getHaloThickness

      public int getHaloThickness()
      Returns the thickness of the halo around the rendered text.
      Returns:
      the thickness of the halo around the rendered text.

    • setHaloThickness

      public void setHaloThickness(int aHaloThickness)
      Sets the thickness of the halo around the rendered text. If this property is changed, a new texture font image will be generated the next time the painter is used, which is a costly operation. Applications should therefore avoid calling this method very frequently.
      Parameters:
      aHaloThickness - the thickness of the halo around the rendered text.

    • isFrameEnabled

      public boolean isFrameEnabled()
      Returns whether or not a frame is drawn around the label.
      Returns:
      whether or not a frame is drawn around the label

    • setFrameEnabled

      public void setFrameEnabled(boolean aFrameEnabled)
      Toggles the use of a frame around the rendered text.
      Parameters:
      aFrameEnabled - a flag indicating whether a frame should be drawn or not

    • getFrameColor

      public Color getFrameColor()
      Returns the color used for a frame around the rendered text
      Returns:
      the color used for a frame around the rendered text

    • setFrameColor

      public void setFrameColor(Color aFrameColor)
      Sets the color used for a frame around the rendered text
      Parameters:
      aFrameColor - the new frame color

    • getBackgroundColor

      public Color getBackgroundColor()
      Returns the color used for filling the background of the rendered text.
      Returns:
      the color used for filling the background of the rendered text

    • setBackgroundColor

      public void setBackgroundColor(Color aBackgroundColor)
      Sets the color used for filling the background of the rendered text to the given color.
      Parameters:
      aBackgroundColor - the new background color

    • isBackgroundEnabled

      public boolean isBackgroundEnabled()
      Returns whether or not the background of the text is filled with the background color.
      Returns:
      whether or not the background of the text is filled with the background color

    • setBackgroundEnabled

      public void setBackgroundEnabled(boolean aBackgroundEnabled)
      Sets whether or not the background of the text is filled with the background color.
      Parameters:
      aBackgroundEnabled - flag indicating whether the background is filled or not

    • drawString

      public void drawString(ILcdGLDrawable aGLDrawable, ILcdPoint aLocation, ILcdBounds aBounds, double aSize, String aString, TLspContext aContext)
      Draws a string at the specified location and with the given size.
      Parameters:
      aGLDrawable - the ILcdGLDrawable to draw the string into
      aLocation - the location at which the string should be drawn
      aBounds - the bounds of the text in view coordinates (used for drawing the frame around the text)
      aSize - the size with which to draw the string, i.e. the height of a line of text
      aString - the string to be drawn

    • drawString

      public void drawString(ILcdGLDrawable aGLDrawable, double aX, double aY, double aZ, double aSize, String aString)
      Draws a string at the specified location and with the given size. The string is drawn as a strip of quadrilaterals in the XY plane; the coordinates aX, aY and aZ specify the lower left corner of the string.

      Other than enabling and binding the font texture, this method does not change any OpenGL state. It is up to the application to set up any required transformations before calling this method (e.g. to ensure that the string is drawn aligned to the screen). In other words, the coordinate reference in which aX, aY, aZ and aSize are expressed, is determined by the current OpenGL state at the time this method is called.

      Parameters:
      aGLDrawable - the ILcdGLDrawable to draw the string into
      aX - the X coordinate of the string's location
      aY - the Y coordinate of the string's location
      aZ - the Z coordinate of the string's location
      aSize - the size with which to draw the string, i.e. the height of a line of text
      aString - the string to be drawn

    • drawStrings

      public void drawStrings(ILcdGLDrawable aGLDrawable, List<ILcdPoint> aPositions, List<ILcdBounds> aBounds, double aSize, List<String> aStrings, TLspContext aContext)

    • bind

      public void bind(ILcdGLDrawable aGLDrawable)
      Description copied from class: ALspGLResource

      Binds this GL resource for use with the given ILcdGLDrawable. Implementations should override this method to perform the appropriate OpenGL call, e.g. glBindTexture(). Inheriting classes must also always invoke super.bind(), as this is required for the correct behavior of ALspGLResource.isBound().

      If this resource was already destroyed and the destroy implementation calls super.destroy, a runtime exception will be thrown when calling this method.

      Overrides:
      bind in class ALspGLResource
      Parameters:
      aGLDrawable - the GL drawable in which this resource is to be bound

    • unbind

      public void unbind(ILcdGLDrawable aGLDrawable)
      Description copied from class: ALspGLResource

      Unbinds this GL resource from the given ILcdGLDrawable. Implementations should override this method to perform whatever OpenGL calls are needed to undo the effects of ALspGLResource.bind(com.luciad.view.opengl.binding.ILcdGLDrawable). Inheriting classes must also always invoke super.unbind(), as this is required for the correct behavior of ALspGLResource.isBound().

      If this resource was already destroyed and the destroy implementation calls super.destroy, a runtime exception will be thrown when calling this method.

      Overrides:
      unbind in class ALspGLResource
      Parameters:
      aGLDrawable - the drawable from which the GL resource should be unbound

    • getStringWidth

      public double getStringWidth(String aString, double aSize)
      Returns the width the specified string would have if it were to be drawn with the given size.
      Parameters:
      aString - the string whose width should be determined
      aSize - the text size based on which the string width should be computed
      Returns:
      the width of the string if it were drawn with the given size
      See Also:

    • drawString

      public void drawString(ILcdGLDrawable aGLDrawable, ILcdPoint aLocation, String aString)
      Draws a string at the specified location with the font's native size.
      Parameters:
      aGLDrawable - the ILcdGLDrawable to draw the string into
      aLocation - the location at which the string should be drawn
      aString - the string to be drawn
      See Also:

    • drawString

      public void drawString(ILcdGLDrawable aGLDrawable, double aX, double aY, double aZ, String aString)
      Draws a string at the specified location with the font's native size.
      Parameters:
      aGLDrawable - the ILcdGLDrawable to draw the string into
      aX - the X coordinate of the string's location
      aY - the Y coordinate of the string's location
      aZ - the Z coordinate of the string's location
      aString - the string to be drawn
      See Also:

    • getNativeSize

      public int getNativeSize()
      Returns the height of a single character glyph in the texture font. When drawing text in view coordinates, this value can be used as the size parameter in calls to drawString(com.luciad.view.opengl.binding.ILcdGLDrawable, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdBounds, double, String, com.luciad.view.lightspeed.TLspContext) to draw characters without scaling. Since scaling could introduce some artifacts due to texture filtering, drawing text at its native size typically improves the text's visual quality.
      Returns:
      the height of a single character glyph in the texture font

    • getStringWidth

      public double getStringWidth(String aString)
      Returns the width the specified string would have if it were to be drawn with the font's native size.
      Parameters:
      aString - the string whose width should be determined
      Returns:
      the width of the string if it were drawn with the font's native size
      See Also:

    • getPadding

      public int getPadding()
      Returns the number of blank pixels added around each character glyph in the texture font. Empty borders are added on all four sides of each glyph so that texture filtering would not cause glyphs to "bleed" into their neighbours when the glyphs are drawn strongly minified.

      The drawString() method already takes this value into account when positioning successive characters in a string, but applications may, for instance, also want to use this method to determine the appropriate amount of spacing between multiple lines of text.

      Returns:
      the amount of padding around each character glyph

    • destroy

      public void destroy(ILcdGLDrawable aGLDrawable)
      Description copied from class: ALspGLResource

      Destroys the OpenGL resource so that it becomes no longer available nor valid to use.

      You should never call this yourself. The GL resource cache will automatically remove old resources. Alternatively, if you don't need the resource anymore, manually remove it from the GL resource cache.

      Extensions of this class should preferably call super.destroy. Doing so will add extra error checking in the bind and unbind methods, to make sure that no destroyed resources are used during painting (this may lead to native crashes).

      Overrides:
      destroy in class ALspGLResource
      Parameters:
      aGLDrawable - the drawable this resource is used for

    • getBytes

      public long getBytes()
      Description copied from class: ALspGLResource
      Gets the estimated number of bytes this resource occupies in GPU memory.
      Specified by:
      getBytes in class ALspGLResource
      Returns:
      the estimated number of bytes

    • getGlyphInfo

      public TLspTextureFont.GlyphInfo getGlyphInfo(char aChar, double aSize)