Enhancements in Java 2D in Java SE 5.0
- Caching All BufferedImages
- Methods for Controlling Hardware Acceleration of Images
- Support for Hardware-Accelerated Rendering Using OpenGL
- Solaris and Linux Support for CUPS Printers
- Bicubic Interpolation
- Creating Fonts from Files and Streams
- Improved Text Rendering Performance and Reliability
- Multilingual Text Rendering
Caching All BufferedImages
As of JDK 5.0, all images created with a BufferedImage constructor are now managed images and can be cached in video memory or, in the case of a remote X server, on the X server side. Earlier, implementations managed only compatible images: those created with the Component createImage(int, int) method or with the GraphicsConfiguration createCompatibleImage methods. Managed images generally perform better than unmanaged images.
Methods for Controlling Hardware Acceleration of Images
The bug report that corresponds to this change is: 4881082
The Image class has three new methods related to hardware acceleration. The getCapabilities method, formerly defined only in VolatileImage, allows you to determine whether the image is currently accelerated. Two other methods let you set or get a hint about how important acceleration is for the image: setAccelerationPriority and getAccelerationPriority.
The GraphicsConfiguration class has two new methods, createCompatibleVolatileImage(int, int, int) and createCompatibleVolatileImage(int, int, ImageCapabilities, int), that allow you to create transparent VolatileImages.
Note: In JDK 5.0, these methods are not fully operational. The value set by
setAccelerationPriority is ignored, and images created with the createCompatibleVolatileImage methods are not always hardware accelerated. On Linux and Solaris systems, only OPAQUE VolatileImages are hardware accelerated. On Microsoft Windows systems, images created with createCompatibleVolatileImage in JDK 5.0 are hardware accelerated only if the hardware supports acceleration and one of the following is true:
- The transparency value is
OPAQUE. - The transparency value is
TRANSLUCENTand translucency acceleration has been specifically enabled at runtime (sun.java2d.translaccel=true).
Support for Hardware-Accelerated Rendering Using OpenGL
The bug reports that correspond to this change are: 4607536 and 5008045.
JDK 5.0 includes a new OpenGL-based pipeline for Java 2D. This pipeline provides hardware acceleration for simple rendering operations (text, images, lines, and filled primitives) as well as those that involve complex transforms, paints, composites, and clips. This pipeline is available on all platforms (Solaris, Linux, and Microsoft Windows) and is currently disabled by default.
To silently enable the OpenGL-based pipeline, specify the following system property on the command line:
-Dsun.java2d.opengl=true
To receive verbose console output about whether the OpenGL-based pipeline is initialized successfully for a particular screen, specify "True" (note the uppercase T):
-Dsun.java2d.opengl=True
Minimum requirements for Solaris/Linux:
- Hardware accelerated OpenGL/GLX libraries installed and configured properly
- OpenGL version 1.2 or higher
- GLX version 1.3 or higher
- At least one TrueColor visual with an available stencil buffer
Minimum requirements for Microsoft Windows:
- Hardware accelerated drivers supporting the WGL_ARB_pbuffer, WGL_ARB_render_texture, and WGL_ARB_pixel_format extensions
- OpenGL version 1.2 or higher
- At least one pixel format with an available stencil buffer
Solaris OpenGL Notes
The following framebuffers are known to work with the OpenGL-based Java 2D pipeline:
- Expert3D
- Expert3D Lite
- XVR-500
- XVR-600
- XVR-1000
- XVR-1200
Accelerated OpenGL libraries for the Solaris x86 platform are not available from Sun. However, third-parties such as Xi Graphics are known to support OpenGL libraries for Solaris x86.
Linux OpenGL Notes
Most Linux distributions include the Mesa 3D graphics library, which is a software implementation of the OpenGL specification. Since Mesa does not take advantage of hardware acceleration, it is likely that the OpenGL-based Java 2D pipeline will run much more slowly than the default (X11-based) pipeline. Therefore, to achieve optimal performance with the OpenGL-based pipeline, it is recommended that you install accelerated OpenGL drivers provided by your graphics hardware manufacturer.
The following web sites may have accelerated OpenGL drivers you can download.
Microsoft Windows OpenGL Notes
To achieve optimal performance with the OpenGL-based pipeline, install accelerated OpenGL drivers provided by your graphics hardware manufacturer. The following websites have accelerated OpenGL drivers available for download that are known to be compatible with the OpenGL-based Java 2D pipeline:
Note: The latest drivers from both Nvidia and ATI have known issues on Microsoft Windows that might cause rendering artifacts in your application. We are actively investigating these driver bugs and are working with the manufacturers to have them resolved in future driver updates.
Solaris and Linux Support for CUPS Printers
The bug reports that correspond to this change are: 4641868 and 4683270
Solaris and Linux systems can now use printers configured as CUPS (Common UNIX Printing System) printers. This expands the printers the Java platform can use to all those supported by CUPS, including most PostScript and raster printers, making it much easier to use low-cost printers with Linux. CUPS is based on IPP (Internet Printing Protocol).
See CUPS for more information.
Bicubic Interpolation
The bug report that corresponds to this change is: 4200154
The 2D implementation now supports bicubic interpolation and uses it whenever requested. Previously, the VALUE_INTERPOLATION_BICUBIC hint defined by the RenderingHints class wasn't honored, and bilinear interpolation was used instead. Now the bicubic rendering hint is honored, and a new constant TYPE_BICUBIC has been added to AffineTransformOp.
Creating Fonts from Files and Streams
The bug reports that correspond to this change are: 4390880 and 4468862
It is now possible to create Font objects from Type 1 fonts and to create Font objects directly from files containing either Type 1 or TrueType font data.
To support the new functionality, the Font class has a new createFont method that creates Font objects from files. The pre-existing createFont method creates Font objects from streams. A new constant, Font.TYPE1_FONT, specifies Type 1 fonts to either createFont method.
Improved Text Rendering Performance and Reliability
The bug report that corresponds to this change is: 4641861
A number of internal changes to text rendering code greatly improve its robustness, performance, and scalability.
Multilingual Text Rendering
The bug report that corresponds to this change is: 4097028
2D text rendering using logical fonts now takes advantage of installed host OS fonts for all supported writing systems to render multilingual text. For example, if you run in a Thai locale environment but have Korean fonts installed, both Thai and Korean are rendered.
