Package com.jogamp.opengl.util.awt

Class 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

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void beginRendering()
      Begins the OpenGL rendering process for the overlay.
      boolean contentsLost()
      Indicates whether the Java 2D contents of the overlay were lost since the last time createGraphics() was called.
      Graphics2D createGraphics()
      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 drawAll()
      Draws the entire contents of the overlay on top of the OpenGL drawable.
      void endRendering()
      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.

    • Constructor Detail

      • Overlay

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

    • Method Detail

      • 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