Class Overlay

java.lang.Object
com.jogamp.opengl.util.awt.Overlay

public class Overlay extends Object
Provides a Java 2D overlay on top of an arbitrary GLDrawable, making it easier to do things like draw text and images on top of an OpenGL scene while still maintaining reasonably good efficiency.
  • Constructor Summary

    Constructors
    Constructor
    Description
    Overlay(GLDrawable drawable)
    Creates a new Java 2D overlay on top of the specified GLDrawable.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    Begins the OpenGL rendering process for the overlay.
    boolean
    Indicates whether the Java 2D contents of the overlay were lost since the last time createGraphics() was called.
    Creates a Graphics2D instance for rendering into the overlay.
    void
    draw(int x, int y, int width, int height)
    Draws the specified sub-rectangle of the overlay on top of the OpenGL drawable.
    void
    draw(int screenx, int screeny, int overlayx, int overlayy, int width, int height)
    Draws the specified sub-rectangle of the overlay at the specified x and y coordinate on top of the OpenGL drawable.
    void
    Draws the entire contents of the overlay on top of the OpenGL drawable.
    void
    Ends the OpenGL rendering process for the overlay.
    void
    markDirty(int x, int y, int width, int height)
    Marks the given region of the overlay as dirty.

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • Overlay

      public Overlay(GLDrawable drawable)
      Creates a new Java 2D overlay on top of the specified GLDrawable.
  • Method Details

    • createGraphics

      public Graphics2D createGraphics()
      Creates a Graphics2D instance for rendering into the overlay. The returned object should be disposed of using the normal Graphics.dispose() method once it is no longer being used.
      Returns:
      a new Graphics2D object for rendering into the backing store of this renderer
    • contentsLost

      public boolean contentsLost()
      Indicates whether the Java 2D contents of the overlay were lost since the last time createGraphics() was called. This method should be called immediately after calling createGraphics() to see whether the entire contents of the overlay need to be redrawn or just the region the application is interested in updating.
      Returns:
      whether the contents of the overlay were lost since the last render
    • markDirty

      public void markDirty(int x, int y, int width, int height)
      Marks the given region of the overlay as dirty. This region, and any previously set dirty regions, will be automatically synchronized with the underlying Texture during the next draw or drawAll operation, at which point the dirty region will be cleared. It is not necessary for an OpenGL context to be current when this method is called.
      Parameters:
      x - the x coordinate (in Java 2D coordinates -- relative to upper left) of the region to update
      y - the y coordinate (in Java 2D coordinates -- relative to upper left) of the region to update
      width - the width of the region to update
      height - the height of the region to update
      Throws:
      GLException - If an OpenGL context is not current when this method is called
    • drawAll

      public void drawAll() throws GLException
      Draws the entire contents of the overlay on top of the OpenGL drawable. This is a convenience method which encapsulates all portions of the rendering process; if this method is used, beginRendering(), endRendering(), etc. should not be used. This method should be called while the OpenGL context for the drawable is current, and after your OpenGL scene has been rendered.
      Throws:
      GLException - If an OpenGL context is not current when this method is called
    • beginRendering

      public void beginRendering() throws GLException
      Begins the OpenGL rendering process for the overlay. This is separated out so advanced applications can render independent pieces of the overlay to different portions of the drawable.
      Throws:
      GLException - If an OpenGL context is not current when this method is called
    • endRendering

      public void endRendering() throws GLException
      Ends the OpenGL rendering process for the overlay. This is separated out so advanced applications can render independent pieces of the overlay to different portions of the drawable.
      Throws:
      GLException - If an OpenGL context is not current when this method is called
    • draw

      public void draw(int x, int y, int width, int height) throws GLException
      Draws the specified sub-rectangle of the overlay on top of the OpenGL drawable. beginRendering() and endRendering() must be used in conjunction with this method to achieve proper rendering results. This method should be called while the OpenGL context for the drawable is current, and after your OpenGL scene has been rendered.
      Parameters:
      x - the lower-left x coordinate (relative to the lower left of the overlay) of the rectangle to draw
      y - the lower-left y coordinate (relative to the lower left of the overlay) of the rectangle to draw
      width - the width of the rectangle to draw
      height - the height of the rectangle to draw
      Throws:
      GLException - If an OpenGL context is not current when this method is called
    • draw

      public void draw(int screenx, int screeny, int overlayx, int overlayy, int width, int height) throws GLException
      Draws the specified sub-rectangle of the overlay at the specified x and y coordinate on top of the OpenGL drawable. beginRendering() and endRendering() must be used in conjunction with this method to achieve proper rendering results. This method should be called while the OpenGL context for the drawable is current, and after your OpenGL scene has been rendered.
      Parameters:
      screenx - the on-screen x coordinate at which to draw the rectangle
      screeny - the on-screen y coordinate (relative to lower left) at which to draw the rectangle
      overlayx - the x coordinate of the pixel in the overlay of the lower left portion of the rectangle to draw
      overlayy - the y coordinate of the pixel in the overlay (relative to lower left) of the lower left portion of the rectangle to draw
      width - the width of the rectangle to draw
      height - the height of the rectangle to draw
      Throws:
      GLException - If an OpenGL context is not current when this method is called