Java Doc for EGL10.java in  » 6.0-JDK-Modules » j2me » javax » microedition » khronos » egl » Java Source Code / Java DocumentationJava Source Code and Java Documentation

The documentation in this interface is normative with respect to instance variable names and values, method names and signatures, and exception behavior. The remaining documentation is placed here for convenience and does not replace the normative documentation found in the EGL specification and relevant extension specifications. EGL documentation is available at the Khronos web site.

Extensions may return values or allow arguments to take on values other than those listed in this specification. Implementations that provide a given extension must pass such values to and from the underlying engine.

If a method throws an exception, the state of the underlying EGL engine is left intact.

All OpenGL ES drawing (except to Pbuffer surfaces) must be preceded by a call to eglWaitNative(EGL10.EGL_CORE_NATIVE_ENGINE, target) where target is a platform-specific object describing the rendering target, and followed by a call to eglWaitGL(). Between these calls, the results of calls or calls to any other drawing API, such as MIDP, JSR 184, java.awt, etc., are undefined. When drawing to an image, the results are not guaranteed to appear in the image pixels until eglWaitGL has returned.

It is not required that calls to methods of this interface be mapped one-to-one onto calls to functions in the underlying EGL implementation. Implementations may contain logic to manage configurations, drawing surface access, threading issues, etc., as required in order to integrate EGL-based APIs with other platform drawing APIs. For example, an implementation that makes use of a software back buffer may translate a call to EGL10.eglCreateWindowSurface into a call to the native function eglCreatePixmapSurface targetting the buffer. Naturally, hardware-accelerated implementations should endeavor to avoid such workarounds.

Drawing to a Pbuffer

A Pbuffer is an invisible, possibly hardware-accelerated buffer. Pbuffer surfaces are created using the EGL10.eglCreatePbufferSurface method. Pbuffers are accessible only from EGL-based APIs, and follow the rules set out in the EGL specification. Pbuffers may be used in the same manner on any Java platform.

The integration between EGL and specific Java ME platforms is as follows.

CLDC/MIDP

On the CLDC/MIDP platform, drawing can be performed to four types of targets: javax.microedition.lcdui.Canvas, javax.microedition.lcdui.game.GameCanvas, (mutable) javax.microedition.lcdui.Image, or to a Pbuffer.

The EGL_DEFAULT_DISPLAY token is used to specify a display.

Drawing to a Canvas or GameCanvas

A Canvas or GameCanvas is specified as a drawing target using the eglCreateWindowSurface method. The native_window argument must be an instance of javax.microedition.lcdui.Graphics that was obtained directly from the argument to the Canvas.paint() method or from the GameCanvas.getGraphics() method. A Graphics instance obtained from the argument to Canvas.paint may be reused in subsequent paint calls targeting the same Canvas.

Drawing to a Canvas or GameCanvas allows for mixing of different drawing APIs.

When drawing to a Canvas (that is not a GameCanvas), drawing must take place entirely within the scope of a system-generated call to the Canvas's paint(Graphics) method. The results of drawing to a Canvas outside the scope of such a call are undefined.

Calling eglSwapBuffers is equivalent to calling glFinish, and does not affect the screen output. The normal GameCanvas.flushGraphics method is used to control screen output.

The initial contents of the back buffer for a GameCanvas are initialized to white, and calls to flushGraphics do not alter the buffer contents.

 import javax.microedition.lcdui.Display;
 import javax.microedition.lcdui.Graphics;
 import javax.microedition.lcdui.game.GameCanvas;
 import javax.microedition.midlet.MIDlet;
 import javax.microedition.khronos.egl.*;
 import javax.microedition.khronos.opengles.*;
 class MyGameCanvas extends GameCanvas {
 EGL11 egl;
 GL11 gl;
 Graphics midpGraphics;
 javax.microedition.m3g.Graphics3D m3gContext;
 MyGameCanvas(MIDlet thisMIDlet) {
 // This example doesn't require key events
 super(true);
 // Get a Graphics instance for MIDP rendering
 // and to use in createWindowSurface
 this.midpGraphics = getGraphics();
 // Show this GameCanvas on the display
 Display display = Display.getDisplay(thisMIDlet);
 display.setCurrent(this);
 // Create an EGL instance
 this.egl = (EGL11)EGLContext.getEGL();
 // Get the EGL display object and initialize EGL
 EGLDisplay eglDisplay = egl.eglGetDisplay(EGL11.EGL_DEFAULT_DISPLAY);
 int[] major_minor = new int[2];
 egl.eglInitialize(eglDisplay, major_minor);
 System.out.println("EGL revision: major = " + major_minor[0]);
 System.out.println("EGL revision: minor = " + major_minor[1]);
 // Determine the number of available configurations
 int[] num_config = new int[1];
 egl.eglGetConfigs(eglDisplay, null, 0, num_config);
 System.out.println("There are " + num_config[0] + " configurations");
 // Locate an 8/8/8 RGB configuration
 int[] configAttrs = { EGL11.EGL_RED_SIZE, 8,
 EGL11.EGL_GREEN_SIZE, 8,
 EGL11.EGL_BLUE_SIZE, 8,
 EGL11.EGL_ALPHA_SIZE, EGL11.EGL_DONT_CARE,
 EGL11.EGL_DEPTH_SIZE, EGL11.EGL_DONT_CARE,
 EGL11.EGL_STENCIL_SIZE, EGL11.EGL_DONT_CARE,
 EGL11.EGL_NONE
 };
 // Grab the first matching config
 EGLConfig[] eglConfigs = new EGLConfig[1];
 egl.eglChooseConfig(eglDisplay, configAttrs,
 eglConfigs, 1, num_config);
 EGLConfig eglConfig = eglConfigs[0];
 // Get a context for EGL rendering
 EGLContext eglContext =
 egl.eglCreateContext(eglDisplay, eglConfig,
 EGL11.EGL_NO_CONTEXT, null);
 // Get a GL object for rendering
 this.gl = (GL11)eglContext.getGL();
 // Bind a window surface to the context
 EGLSurface eglSurface =
 egl.eglCreateWindowSurface(eglDisplay, eglConfig, midpGraphics, null);
 // Make the context current for future GL calls
 egl.eglMakeCurrent(eglDisplay, eglSurface, eglSurface, eglContext);
 // Get a context for M3G rendering
 this.m3g = ...;
 }
 // The update loop
 public void run() {
 while (true) {
 // Do some MIDP 2D rendering
 // Use of OpenGL ES or M3G is not allowed here
 // MIDP primitives drawn here will appear underneath the
 // OpenGL ES drawing
 midpGraphics.drawLine(...);
 // Wait for MIDP drawing to complete
 egl.eglWaitNative(EGL11.EGL_CORE_NATIVE_ENGINE, midpGraphics);
 // Now it is O.K. to use OpenGL ES drawing APIs
 // Do some OpenGL ES rendering
 // Use of MIDP, JSR 184, or other drawing APIs is undefined here
 gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
 gl.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT);
 gl.glFrustumf(...);
 // etc.
 // Wait for OpenGL ES rendering to complete
 egl.eglWaitGL();
 // Now it is O.K. to use MIDP drawing APIs
 // MIDP primitives drawn here will appear on top of the
 // OpenGL ES drawing
 midpGraphics.drawRect(...);
 // Do some M3G (JSR 184) rendering
 m3g.bindTarget(midpGraphics, ...);
 // Now it is O.K. to use M3G, but not MIDP or OpenGL ES
 // M3G commands go here
 // Wait for M3G drawing to complete
 m3g.releaseTarget();
 // Now it is O.K. to use MIDP drawing APIs
 // Do some more MIDP 2D rendering
 // MIDP primitives drawn here will appear on top of the
 // OpenGL ES and M3G drawings
 midp_graphics.drawArc(...);
 // Flush the back buffer to the screen
 flushGraphics();
 }
 }
 }
 

Drawing to an Image

The eglCreatePixmapSurface method allows drawing to an Image. The Image must be mutable. The native_pixmap argument must be an instance of javax.microedition.lcdui.Graphics that was obtained from the Image's getGraphics() method.

OpenGL ES drawing must be bracketed between calls to eglWaitNative and eglWaitGL in the same manner as for Canvas and GameCanvas. Calling eglSwapBuffers is equivalent to calling glFinish, since there is no back buffer.

Other platforms

The current specification does not address AWT-based platforms such as CDC/Personal Basis Profile, CDC/Personal Profile, and Java Standard Edition. The details of how to bind to displays and surfaces on these platforms will be provided in a future release of the specification.

On a JME CLDC/MIDP platform, this specifies the MIDP/LCDUI drawing engine.

eglChooseConfig returns a list of all EGL frame buffer configurations that match the attributes specified in attrib_list. The items in the list can be used in any EGL function that requires an EGL frame buffer configuration.

configs does not return values, if it is specified as null. This is useful for querying just the number of matching frame buffer configurations.

All attributes in attrib_list, including boolean attributes, are immediately followed by the corresponding desired value. The list is terminated with EGL_NONE. If an attribute is not specified in attrib_list then the default value (see below) is used (and the attribute is said to be specified implicitly). For example, if EGL_DEPTH_SIZE is not specified then it is assumed to be 0. For some attributes, the default is EGL_DONT_CARE meaning that any value is OK for this attribute, so the attribute will not be checked.

If attrib_list is null or empty (first attribute is EGL_NONE), then selection and sorting of EGLConfigs is done according to the default criteria described below.

Attributes are matched in an attribute-specific manner. Some of the attributes, such as EGL_LEVEL, must match the specified value exactly. Others, such as, EGL_RED_SIZE must meet or exceed the specified minimum values. If more than one EGL frame buffer configuration is found, then a list of configurations, sorted according to the "best" match criteria, is returned. The match criteria for each attribute and the exact sorting order is defined below.

The interpretations of the various EGL frame buffer configuration attributes are as follows:

• EGL_BUFFER_SIZE

Must be followed by a nonnegative integer that indicates the desired color buffer size. The smallest color buffer of at least the specified size is preferred. The default value is 0.

• EGL_RED_SIZE

Must be followed by a nonnegative minimum size specification. If this value is zero, the smallest available red buffer is preferred. Otherwise, the largest available red buffer of at least the minimum size is preferred. The default value is 0.

• EGL_GREEN_SIZE

Must be followed by a nonnegative minimum size specification. If this value is zero, the smallest available green buffer is preferred. Otherwise, the largest available green buffer of at least the minimum size is preferred. The default value is 0.

• EGL_BLUE_SIZE

Must be followed by a nonnegative minimum size specification. If this value is zero, the smallest available blue buffer is preferred. Otherwise, the largest available blue buffer of at least the minimum size is preferred. The default value is 0.

• EGL_ALPHA_SIZE

Must be followed by a nonnegative minimum size specification. If this value is zero, the smallest available alpha buffer is preferred. Otherwise, the largest available alpha buffer of at least the minimum size is preferred. The default value is 0.

• EGL_CONFIG_CAVEAT

Must be followed by one of EGL_DONT_CARE, EGL_NONE, EGL_SLOW_CONFIG, EGL_NON_CONFORMANT_CONFIG. If EGL_NONE is specified, then only frame buffer configurations with no caveats will be considered. If EGL_SLOW_CONFIG is specified, then only slow frame buffer configurations will be considered. If EGL_NON_CONFORMANT_CONFIG is specified, then only non-conformant frame buffer configurations will be considered. The default value is EGL_DONT_CARE.

• EGL_CONFIG_ID

Must be followed by a valid ID that indicates the desired EGL frame buffer configuration. When a EGL_CONFIG_ID is specified, all attributes are ignored. The default value is EGL_DONT_CARE.

• EGL_DEPTH_SIZE

Must be followed by a nonnegative integer that indicates the desired depth buffer size. The smallest available depth buffer of at least the minimum size is preferred. If the desired value is zero, frame buffer configurations with no depth buffer are preferred. The default value is 0.

• EGL_LEVEL

Must be followed by an integer buffer-level specification. This specification is honored exactly. Buffer level 0 corresponds to the default frame buffer of the display. Buffer level 1 is the first overlay frame buffer, level two the second overlay frame buffer, and so on. Negative buffer levels correspond to underlay frame buffers. The default value is 0.

• EGL_NATIVE_RENDERABLE

Must be followed by EGL_DONT_CARE, EGL_TRUE, or EGL_FALSE. If EGL_TRUE is specified, then only frame buffer configurations that allow native rendering into the surface will be considered. The default value is EGL_DONT_CARE.

• EGL_NATIVE_VISUAL_TYPE (1.0 only)

Must be followed by a platform dependent value or EGL_DONT_CARE. The default value is EGL_DONT_CARE.

• EGL_SAMPLE_BUFFERS

Must be followed by the minimum acceptable number of multisample buffers. Configurations with the smallest number of multisample buffers that meet or exceed this minimum number are preferred. Currently operation with more than one multisample buffer is undefined, so only values of zero or one will produce a match. The default value is 0.

• EGL_SAMPLES

Must be followed by the minimum number of samples required in multisample buffers. Configurations with the smallest number of samples that meet or exceed the specified minimum number are preferred. Note that it is possible for color samples in the multisample buffer to have fewer bits than colors in the main color buffers. However, multisampled colors maintain at least as much color resolution in aggregate as the main color buffers.

• EGL_STENCIL_SIZE

Must be followed by a nonnegative integer that indicates the desired number of stencil bitplanes. The smallest stencil buffer of at least the specified size is preferred. If the desired value is zero, frame buffer configurations with no stencil buffer are preferred. The default value is 0.

• EGL_SURFACE_TYPE

Must be followed by a mask indicating which EGL surface types the frame buffer configuration must support. Valid bits are EGL_WINDOW_BIT, EGL_PBUFFER_BIT, and EGL_PIXMAP_BIT. For example, if mask is set to EGL_WINDOW_BIT | EGL_PIXMAP_BIT, only frame buffer configurations that support both windows and pixmaps will be considered. The default value is EGL_WINDOW_BIT.

• EGL_TRANSPARENT_TYPE

Must be followed by one of EGL_NONE or EGL_TRANSPARENT_RGB. If EGL_NONE is specified, then only opaque frame buffer configurations will be considered. If EGL_TRANSPARENT_RGB is specified, then only transparent frame buffer configurations will be considered. The default value is EGL_NONE.

• EGL_TRANSPARENT_RED_VALUE

Must be followed by an integer value indicating the transparent red value. The value must be between 0 and the maximum color buffer value for red. Only frame buffer configurations that use the specified transparent red value will be considered. The default value is EGL_DONT_CARE.

This attribute is ignored unless EGL_TRANSPARENT_TYPE is included in attrib_list and specified as EGL_TRANSPARENT_RGB.

• EGL_TRANSPARENT_GREEN_VALUE

Must be followed by an integer value indicating the transparent green value. The value must be between 0 and the maximum color buffer value for red. Only frame buffer configurations that use the specified transparent green value will be considered. The default value is EGL_DONT_CARE.

This attribute is ignored unless EGL_TRANSPARENT_TYPE is included in attrib_list and specified as EGL_TRANSPARENT_RGB.

• EGL_TRANSPARENT_BLUE_VALUE

Must be followed by an integer value indicating the transparent blue value. The value must be between 0 and the maximum color buffer value for red. Only frame buffer configurations that use the specified transparent blue value will be considered. The default value is EGL_DONT_CARE.

This attribute is ignored unless EGL_TRANSPARENT_TYPE is included in attrib_list and specified as EGL_TRANSPARENT_RGB.

• EGL_BIND_TO_TEXTURE_RGB (1.1 only)

Must be followed by EGL_DONT_CARE, EGL_TRUE, or EGL_FALSE. If EGL_TRUE is specified, then only frame buffer configurations that support binding of color buffers to an RGB texture will be considered. Currently only frame buffer configurations that support pbuffers allow this. The default value is EGL_DONT_CARE.

• EGL_BIND_TO_TEXTURE_RGBA (1.1 only)>

Must be followed by EGL_DONT_CARE, EGL_TRUE, or EGL_FALSE. If EGL_TRUE is specified, then only frame buffer configurations that support binding of color buffers to an RGBA texture will be considered. Currently only frame buffer configurations that support pbuffers allow this. The default value is EGL_DONT_CARE.

• EGL_MAX_SWAP_INTERVAL (1.1 only)

Must be followed by a integer that indicates the maximum value that can be passed to eglSwapInterval. The default value is EGL_DONT_CARE.

• EGL_MIN_SWAP_INTERVAL (1.1 only)

Must be followed by a integer that indicates the minimum value that can be passed to eglSwapInterval. The default value is EGL_DONT_CARE.

When more than one EGL frame buffer configuration matches the specified attributes, a list of matching configurations is returned. The list is sorted according to the following precedence rules, which are applied in ascending order (i.e., configurations that are considered equal by a lower numbered rule are sorted by the higher numbered rule):

1. By EGL_CONFIG_CAVEAT, where the precedence is EGL_NONE, EGL_SLOW_CONFIG, and EGL_NON_CONFORMANT_CONFIG.
2. Larger total number of color components (EGL_RED_SIZE, EGL_GREEN_SIZE, EGL_BLUE_SIZE, and EGL_ALPHA_SIZE) that have higher number of bits. If the requested number of bits in attrib_list is zero or EGL_DONT_CARE for a particular color component, then the number of bits for that component is not considered.
3. Smaller EGL_BUFFER_SIZE.
4. Smaller EGL_SAMPLE_BUFFERS.
5. Smaller EGL_SAMPLES.
6. Smaller EGL_DEPTH_SIZE.
7. Smaller EGL_STENCIL_SIZE.
8. By EGL_NATIVE_VISUAL_TYPE, where the precedence order is platform dependent.
9. Smaller EGL_CONFIG_ID.

(1.1) EGLConfigs are not sorted with respect to the parameters EGL_BIND_TO_TEXTURE_RGB, EGL_BIND_TO_TEXTURE_RGBA, EGL_LEVEL, EGL_NATIVE_RENDERABLE, EGL_MAX_SWAP_INTERVAL, EGL_MIN_SWAP_INTERVAL, EGL_SURFACE_TYPE, EGL_TRANSPARENT_TYPE, EGL_TRANSPARENT_RED_VALUE, EGL_TRANSPARENT_GREEN_VALUE, and EGL_TRANSPARENT_BLUE_VALUE.

Examples

The following example specifies a frame buffer configuration in the normal frame buffer (not an overlay or underlay). The returned frame buffer configuration supports at least 4 bits each of red, green and blue and possible no alpha bits. The code shown in the example may or may not have a depth buffer, or a stencil buffer.

 int attrib_list[] = {
 EGL10.EGL_RED_SIZE, 4,
 EGL10.EGL_GREEN_SIZE, 4,
 EGL10.EGL_BLUE_SIZE, 4,
 EGL10.EGL_NONE
 };
 

Notes

eglGetConfigs and eglGetConfigAttrib can be used to implement selection algorithms other than the generic one implemented by eglChooseConfig. Call eglGetConfigs to retrieve all the frame buffer configurations, or alternatively, all the frame buffer configurations with a particular set of attributes. Next call eglGetConfigAttrib to retrieve additional attributes for the frame buffer configurations and then select between them.

EGL implementors are strongly discouraged, but not proscribed, from changing the selection algorithm used by eglChooseConfig. Therefore, selections may change from release to release of the client-side library.

Errors

false is returned on failure, true otherwise. configs and num_config are not modified when false is returned.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_BAD_ATTRIBUTE is generated if attribute_list contains an invalid frame buffer configuration attribute or an attribute value that is unrecognized or out of range.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_PARAMETER is generated if num_config is null.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  attrib_list - Specifies attributes required to match by configs.
Parameters:
  configs - Returns an array of frame buffer configurations.
Parameters:
  config_size - Specifies the size of the array of framebuffer configurations.
Parameters:
  num_config - An int array in which the number of framebuffer configurations will be returned in element 0. true if the operation succeeds.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if attrib_list isnon-null but is not terminated withEGL_NONE.
exception:
  IllegalArgumentException - if configs isnon-null and configs.length is smallerthan config_size.
exception:
  IllegalArgumentException - if num_config isnon-null but has length less than 1.

eglCopyBuffers copies the color buffer of surface to native_pixmap.

eglCopyBuffers performs an implicit glFlush before it returns. Subsequent GL commands may be issued immediately after calling eglCopyBuffers, but are not executed until copying of the color buffer is completed.

Notes

The color buffer of surface is left unchanged after calling eglCopyBuffers.

On JME CLDC/MIDP platforms, native_pixmap must be an instance of javax.microedition.lcdui.Image that is mutable, or an instance of javax.microedition.lcdui.Graphics that was obtained directly from such an image by means of a call to createGraphics() or getGraphics().

Errors

false is returned if swapping of the surface buffers fails, true otherwise.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_SURFACE is generated if surface is not an EGL drawing surface.

EGL_BAD_NATIVE_PIXMAP is generated if the implementation does not support native pixmaps.

EGL_BAD_NATIVE_PIXMAP may be generated if native_pixmap is not a valid native pixmap.

EGL_BAD_MATCH is generated if the format of native_pixmap is not compatible with the color buffer of surface.

(1.1 only) EGL_CONTEXT_LOST is generated if a power management event has occurred. The application must destroy all contexts and reinitialize OpenGL ES state and objects to continue rendering.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  surface - Specifies the EGL surface whose color buffer is tobe copied.
Parameters:
  native_pixmap - Specifies the native pixmap as target of thecopy.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if surface isnull.
exception:
  IllegalArgumentException - if native_pixmapis null or is not of a suitable type for theunderlying platform (e.g., a mutable Image for CLDC/MIDP). true if the copy succeeds.

eglCreateContext creates an EGL rendering context and returns its handle. This context can be used to render into an EGL drawing surface. If eglCreateContext fails to create a rendering context, EGL_NO_CONTEXT is returned.

If share_context is not EGL_NO_CONTEXT, then all texture objects except object 0, are shared by context share_context and by the newly created context. An arbitrary number of rendering contexts can share a single texture object space. However, all rendering contexts that share a single texture object space must themselves exist in the same address space. Two rendering contexts share an address space if both are owned by a single process.

Currently no attributes are recognized, so attrib_list will normally be null or empty (first attribute is EGL_NONE). However, it is possible that some platforms will define attributes specific to those environments, as an EGL extension. A non-null attribute list that is terminated with EGL_NONE will be passed to the underlying EGL implementation.

Errors

EGL_NO_CONTEXT is returned if creation of the context fails.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONFIG is generated if config is not an EGL frame buffer configuration.

EGL_BAD_CONTEXT is generated if share_context is not an EGL rendering context and is not EGL_NO_CONTEXT.

EGL_BAD_ATTRIBUTE is generated if attrib_list contains an invalid context attribute or if an attribute is not recognized or out of range.

EGL_BAD_ALLOC is generated if there are not enough resources to allocate the new context.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  config - Specifies the EGL frame buffer configuration thatdefines the frame buffer resource available to the renderingcontext.
Parameters:
  share_context - Specifies the EGL rendering context withwhich to share texture objects. EGL_NO_CONTEXTindicates that no sharing is to take place.
Parameters:
  attrib_list - Specifies attributes. A new EGLContext, or nullif context creation was unsuccessful.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if config isnull.
exception:
  IllegalArgumentException - if share_context isnull.
exception:
  IllegalArgumentException - if attrib_list isnon-null but is not terminated withEGL_NONE.

eglCreatePbufferSurface creates an off-screen pixel buffer surface and returns its handle. If eglCreatePbufferSurface fails to create a pixel buffer surface, EGL_NO_SURFACE is returned.

Any EGL rendering context that was created with respect to config can be used to render into the surface. Use eglMakeCurrent to attach an EGL rendering context to the surface.

Use eglQuerySurface to retrieve the dimensions of the allocated pixel buffer surface or the ID of config.

Use eglDestroySurface to destroy the surface.

The pixel buffer surface attributes are specified in attrib_list as a list of attribute value pairs, terminated with EGL_NONE. A null value for attrib_list is treated as an empty list. The accepted attributes for an EGL pixel buffer surface are:

• EGL_WIDTH

Specifies the requested width of the pixel buffer surface. The default value is 0.

• EGL_HEIGHT

Specifies the requests height of the pixel buffer surface. The default value is 0.

• EGL_LARGEST_PBUFFER

Requests the largest available pixel buffer surface when the allocation would otherwise fail. Use eglQuerySurface to retrieve the dimensions of the allocated pixel buffer. The default value is EGL_FALSE.

• EGL_TEXTURE_FORMAT (1.1 only)

Specifies the format of the texture that will be created when a pbuffer is bound to a texture map. Possible values are EGL_NO_TEXTURE, EGL_TEXTURE_RGB, and EGL_TEXTURE_RGBA. The default value is EGL_NO_TEXTURE.

• EGL_TEXTURE_TARGET (1.1 only)

Specifies the target for the texture that will be created when the pbuffer is created with a texture format of EGL_TEXTURE_RGB or EGL_TEXTURE_RGBA. Possible values are EGL_NO_TEXTURE, or EGL_TEXTURE_2D. The default value is EGL_NO_TEXTURE.

• EGL_MIPMAP_TEXTURE (1.1 only)

Specifies whether storage for mipmaps should be allocated. Space for mipmaps will be set aside if the attribute value is EGL_TRUE and EGL_TEXTURE_FORMAT is not EGL_NO_TEXTURE. The default value is EGL_FALSE.

1.1 Notes

If the value of config attribute EGL_TEXTURE_FORMAT is not EGL_NO_TEXTURE, then the pbuffer width and height specify the size of the level zero texture image

If EGL_LARGEST_PBUFFER is specified and if the pbuffer will be used as a texture (i.e. the value of EGL_TEXTURE_TARGET is EGL_TEXTURE_2D, and the value of EGL_TEXTURE FORMAT is EGL_TEXTURE_RGB or EGL_TEXTURE_RGBA), then the aspect ratio will be preserved and the new width and height will be valid sizes for the texture target (e.g. if the underlying OpenGL ES implementation does not support non-power-of-two textures, both the width and height will be a power of 2).

The contents of the depth and stencil buffers may not be preserved when rendering a texture to the pbuffer and switching which image of the texture is rendered to (e.g., switching from rendering one mipmap level to rendering another).

Errors

EGL_NO_SURFACE is returned if creation of the context fails.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONFIG is generated if config is not an EGL frame buffer configuration.

EGL_BAD_ATTRIBUTE is generated if attrib_list contains an invalid pixel buffer attribute or if an attribute value is not recognized or out of range.

EGL_BAD_ALLOC is generated if there are not enough resources to allocate the new surface.

EGL_BAD_MATCH is generated if config does not support rendering to pixel buffers (the EGL_SURFACE_TYPE attribute does not contain EGL_PBUFFER_BIT).

(1.1 only) EGL_BAD_VALUE is generated if the EGL_TEXTURE_FORMAT attribute is not EGL_NO_TEXTURE, and EGL_WIDTH and/or EGL_HEIGHT specify an invalid size (e.g., the texture size is not a power of 2, and the underlying OpenGL ES implementation does not support non-power-of-two textures).

(1.1 only) EGL_BAD_VALUE can also be generated if The EGL_TEXTURE_FORMAT attribute is EGL_NO_TEXTURE, and EGL_TEXTURE_TARGET is something other than EGL_NO_TEXTURE; or, EGL_TEXTURE_FORMAT is something other than EGL_NO_TEXTURE, and EGL_TEXTURE_TARGET is EGL_NO_TEXTURE.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  config - Specifies the EGL frame buffer configuration thatdefines the frame buffer resource available to the surface.
Parameters:
  attrib_list - Specifies the pixel buffer surfaceattributes. May be null or empty (first attribute isEGL_NONE). An EGLSurface for offscreen rendering.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if config isnull.
exception:
  IllegalArgumentException - if attrib_listis non-null but is not terminated withEGL_NONE.

eglCreatePixmapSurface creates an off-screen EGL pixmap surface and returns its handle. If eglCreatePixmapSurface fails to create a pixmap surface, EGL_NO_SURFACE is returned.

Any EGL rendering context that was created with respect to config can be used to render into the surface. Use eglMakeCurrent to attach an EGL rendering context to the surface.

Use eglQuerySurface to retrieve the ID of config.

Use eglDestroySurface to destroy the surface.

Notes

On JME CLDC/MIDP platforms, native_pixmap must be an instance of javax.microedition.lcdui.Graphics that was created directly from a mutable instance of javax.microedition.lcdui.Image.

Errors

EGL_NO_SURFACE is returned if creation of the context fails.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONFIG is generated if config is not an EGL config.

EGL_BAD_NATIVE_PIXMAP may be generated if native_pixmap is not a valid native pixmap.

EGL_BAD_ATTRIBUTE is generated if attrib_list contains an invalid pixmap attribute or if an attribute value is not recognized or out of range.

EGL_BAD_ALLOC is generated if there are not enough resources to allocate the new surface.

EGL_BAD_MATCH is generated if the attributes of native_pixmap do not correspond to config or if config does not support rendering to pixmaps (the EGL_SURFACE_TYPE attribute does not contain EGL_PIXMAP_BIT).
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  config - Specifies the EGL frame buffer configuration thatdefines the frame buffer resource available to the surface.
Parameters:
  native_pixmap - Specifies the native pixmap.
Parameters:
  attrib_list - Specifies pixmap surface attributes. Must benull or empty (first attribute is EGL_NONE). An EGLSurface for offscreen rendering.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if config isnull
exception:
  IllegalArgumentException - if native_pixmapis null or is not of a suitable type for theunderlying platform (e.g., not a mutable Image forCLDC/MIDP).
exception:
  IllegalArgumentException - if attrib_listis non-null but is not terminated withEGL_NONE.

eglCreateWindowSurface creates an EGL window surface and returns its handle. If eglCreateWindowSurface fails to create a window surface, EGL_NO_SURFACE is returned.

Any EGL rendering context that was created with respect to config can be used to render into the surface. Use eglMakeCurrent to attach an EGL rendering context to the surface.

Use eglQuerySurface to retrieve the ID of config.

Use eglDestroySurface to destroy the surface.

Notes

On JME CLDC/MIDP platforms, native_window must be an instance of javax.microedition.lcdui.Graphics object created directly from an instance of GameCanvas or from the argument supplied to the Canvas.paint method.

Errors

EGL_NO_SURFACE is returned if creation of the context fails.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONFIG is generated if config is not an EGL frame buffer configuration.

EGL_BAD_NATIVE_WINDOW may be generated if native_window is not a valid native window.

EGL_BAD_ATTRIBUTE is generated if attrib_list contains an invalid window attribute or if an attribute value is not recognized or is out of range.

EGL_BAD_ALLOC is generated if there are not enough resources to allocate the new surface.

EGL_BAD_MATCH is generated if the attributes of native_window do not correspond to config or if config does not support rendering to windows (the EGL_SURFACE_TYPE attribute does not contain EGL_WINDOW_BIT).
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  config - Specifies the EGL frame buffer configuration thatdefines the frame buffer resource available to the surface.
Parameters:
  native_window - Specifies the native window.
Parameters:
  attrib_list - Specifies window surface attributes. Must benull or empty (first attribute is EGL_NONE). an EGLSurface for rendering to the window.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if config isnull.
exception:
  IllegalArgumentException - if native_windowis null or is not of a suitable type for theunderlying platform (e.g., not a properly-createdjavax.microedition.lcdui.Graphics instance forCLDC/MIDP).
exception:
  IllegalArgumentException - if attrib_listis non-null but is not terminated withEGL_NONE.

If the EGL rendering context context is not current to any thread, eglDestroyContext destroys it immediately. Otherwise, context is destroyed when it becomes not current to any thread.

Errors

false is returned if destruction of the context fails, true otherwise.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONTEXT is generated if context is not an EGL rendering context.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  context - Specifies the EGL rendering context to be destroyed.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if context isnull. true if the operation succeeds.

If the EGL surface surface is not current to any thread, eglDestroySurface destroys it immediately. Otherwise, surface is destroyed when it becomes not current to any thread.

(1.1) In OpenGL ES 1.1, resources associated with a pbuffer surface are not released until all color buffers of that pbuffer bound to a texture object have been released.

Errors

false is returned if destruction of the surface fails, true otherwise.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_SURFACE is generated if surface is not an EGL surface.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  surface - Specifies the EGL surface to be destroyed.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if surface isnull. true if the operation succeeds.

eglGetConfigAttrib returns in value[0] the value of attribute for config. attribute can be one of the following:

• EGL_BUFFER_SIZE

Returns the depth of the color buffer. It is the sum of EGL_RED_SIZE, EGL_GREEN_SIZE, EGL_BLUE_SIZE, and EGL_ALPHA_SIZE.

• EGL_RED_SIZE

Returns the number of bits of red stored in the color buffer.

• EGL_GREEN_SIZE

Returns the number of bits of green stored in the color buffer.

• EGL_BLUE_SIZE

Returns the number of bits of blue stored in the color buffer.

• EGL_ALPHA_SIZE

Returns the number of bits of alpha stored in the color buffer.

• EGL_CONFIG_CAVEAT

Returns the caveats for the frame buffer configuration. Possible caveat values are EGL_NONE, EGL_SLOW_CONFIG, and EGL_NON_CONFORMANT.

• EGL_CONFIG_ID

Returns the ID of the frame buffer configuration.

• EGL_DEPTH_SIZE

Returns the number of bits in the depth buffer.

• EGL_LEVEL

Returns the frame buffer level. Level zero is the default frame buffer. Positive levels correspond to frame buffers that overlay the default buffer and negative levels correspond to frame buffers that underlay the default buffer.

• EGL_MAX_PBUFFER_WIDTH

Returns the maximum width of a pixel buffer surface in pixels.

• EGL_MAX_PBUFFER_HEIGHT

Returns the maximum height of a pixel buffer surface in pixels.

• EGL_MAX_PBUFFER_PIXELS

Returns the maximum size of a pixel buffer surface in pixels.

• EGL_NATIVE_RENDERABLE

Returns EGL_TRUE if native rendering APIs can render into the surface, EGL_FALSE otherwise.

• EGL_NATIVE_VISUAL_ID

Returns the ID of the associated native visual.

• EGL_NATIVE_VISUAL_TYPE

Returns the type of the associated native visual.

• EGL_PRESERVED_RESOURCES (1.0 only)
Returns EGL_TRUE if resources are preserved across power management events, EGL_FALSE otherwise.
• EGL_SAMPLE_BUFFERS

Returns the number of multisample buffers.

• EGL_SAMPLES

Returns the number of samples per pixel.

• EGL_STENCIL_SIZE

Returns the number of bits in the stencil buffer.

• EGL_SURFACE_TYPE

Returns the types of supported EGL surfaces.

• EGL_TRANSPARENT_TYPE

Returns the type of supported transparency. Possible transparency values are: EGL_NONE, and EGL_TRANSPARENT_RGB.

• EGL_TRANSPARENT_RED_VALUE

Returns the transparent red value.

• EGL_TRANSPARENT_GREEN_VALUE

Returns the transparent green value.

• EGL_TRANSPARENT_BLUE_VALUE

Returns the transparent blue value.

• EGL_BIND_TO_TEXTURE_RGB (1.1 only)

Returns EGL_TRUE if color buffers can be bound to an RGB texture, EGL_FALSE otherwise.

• EGL_BIND_TO_TEXTURE_RGBA (1.1 only)

Returns EGL_TRUE if color buffers can be bound to an RGBA texture, EGL_FALSE otherwise.

• EGL_MAX_SWAP_INTERVAL (1.1 only)

Returns the maximum value that can be passed to eglSwapInterval.

• EGL_MIN_SWAP_INTERVAL (1.1 only)

Returns the minimum value that can be passed to eglSwapInterval.

Errors

false is returned on failure, true otherwise. value is not modified when false is returned.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONFIG is generated if config is not an EGL frame buffer configuration.

EGL_BAD_ATTRIBUTE is generated if attribute is not a valid frame buffer configuration attribute.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  config - Specifies the EGL frame buffer configuration to be queried.
Parameters:
  attribute - Specifies the EGL rendering context attribute tobe returned.
Parameters:
  value - An int array of length at least 1 inwhich the requested value will be returned as element 0.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if config isnull.
exception:
  IllegalArgumentException - if value isnull or has length less than 1. true if the query succeeds.

eglGetConfigs returns a list of all EGL frame buffer configurations that are available for the specified display. The items in the list can be used in any EGL function that requires an EGL frame buffer configuration. No more than config_size EGLConfigs will be returned even if more are available on the specified display.

configs does not return values, if it is specified as null. This is useful for querying just the number of all frame buffer configurations.

Use eglGetConfigAttrib to retrieve individual attribute values of a frame buffer configuration.

Errors

false is returned on failure, true otherwise. configs and num_config are not modified when false is returned.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_PARAMETER is generated if num_config is null.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  configs - An array of EGLConfig objects intowhich a list of configs will be stored, or null.
Parameters:
  config_size - Specifies the size of the list of configs.
Parameters:
  num_config - An int array, in which the numberof configs will be returned in element 0. true if the operation succeeds.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if configs isnon-null and configs.length is smallerthan config_size.
exception:
  IllegalArgumentException - if num_config isnon-null but has length less than 1.

eglGetCurrentContext returns the current EGL rendering context, as specified by eglMakeCurrent. If no context is current, EGL_NO_CONTEXT is returned. The current EGLContext, orEGL_NO_CONTEXT.

eglGetCurrentDisplay returns the current EGL display connection for the current EGL rendering context, as specified by eglMakeCurrent. If no context is current, EGL_NO_DISPLAY is returned. The current EGLDisplay

eglGetCurrentSurface returns the read or draw surface attached to the current EGL rendering context, as specified by eglMakeCurrent. If no context is current, EGL_NO_SURFACE is returned.
Parameters:
  readdraw - Specifies whether the EGL read or draw surface isto be returned, one of EGL_READ orEGL_DRAW. The current EGLSurface used for reading (ifreaddraw equals EGL_READ, or drawing(if readdraw equals EGL_DRAW).
exception:
  IllegalArgumentException - if readdraw isnot one of the specified constants.

eglGetDisplay obtains the EGL display connection for the native display native_display.

If display_id is EGL_DEFAULT_DISPLAY, a default display connection is returned.

If no display connection matching native_display is available, EGL_NO_DISPLAY is returned. No error is generated.

Use eglInitialize to initialize the display connection.
Parameters:
  native_display - Specifies the display to connectto. EGL_DEFAULT_DISPLAY indicates the defaultdisplay. An EGLDisplay object.
exception:
  IllegalArgumentException - if native_display isnull or is not of a suitable type for the platform.

eglGetError returns the error of the last called EGL function in the current thread. Initially, the error is set to EGL_SUCCESS.

The following errors are currently defined:

• EGL_SUCCESS

The last function succeeded without error.

• EGL_NOT_INITIALIZED

EGL is not initialized, or could not be initialized, for the specified EGL display connection.

• EGL_BAD_ACCESS

EGL cannot access a requested resource (for example a context is bound in another thread).

• EGL_BAD_ALLOC

EGL failed to allocate resources for the requested operation.

• EGL_BAD_ATTRIBUTE

An unrecognized attribute or attribute value was passed in the attribute list.

• EGL_BAD_CONTEXT

An EGLContext argument does not name a valid EGL rendering context.

• EGL_BAD_CONFIG

An EGLConfig argument does not name a valid EGL frame buffer configuration.

• EGL_BAD_CURRENT_SURFACE

The current surface of the calling thread is a window, pixel buffer or pixmap that is no longer valid.

• EGL_BAD_DISPLAY

An EGLDisplay argument does not name a valid EGL display connection.

• EGL_BAD_SURFACE

An EGLSurface argument does not name a valid surface (window, pixel buffer or pixmap) configured for GL rendering.

• EGL_BAD_MATCH

Arguments are inconsistent (for example, a valid context requires buffers not supplied by a valid surface).

• EGL_BAD_PARAMETER

One or more argument values are invalid.

• EGL_BAD_NATIVE_PIXMAP

A native_pixmap argument does not refer to a valid native pixmap.

• EGL_BAD_NATIVE_WINDOW

A native_window argument does not refer to a valid native window.

• EGL_CONTEXT_LOST (1.1 only)

A power management event has occurred. The application must destroy all contexts and reinitialise OpenGL ES state and objects to continue rendering.

Errors

A call to eglGetError sets the error to EGL_SUCCESS. One of EGL_SUCCESS,EGL_NOT_INITIALIZED, EGL_BAD_ACCESS,EGL_BAD_ALLOC, EGL_BAD_ATTRIBUTE,EGL_BAD_CONTEXT, EGL_BAD_CONFIG,EGL_BAD_CURRENT_SURFACE,EGL_BAD_DISPLAY, EGL_BAD_MATCH,EGL_BAD_NATIVE_PIXMAP,EGL_BAD_NATIVE_WINDOW,EGL_BAD_PARAMETER, EGL_BAD_SURFACE, orother error code defined by an extension.

eglInitialize initializes the EGL display connection obtained with eglGetDisplay. Initializing an already initialized EGL display connection has no effect besides returning the version numbers and returing true.

No value is returned in major_minor if it is specified as null.

Use eglTerminate to release resources associated with an EGL display connection.

Errors

false is returned if eglInitialize fails, true otherwise. major_minor is not modified when false is returned.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display cannot be initialized.
Parameters:
  display - Specifies the EGL display connection to initialize.
Parameters:
  major_minor - an int array of length at least2, in which the major and minor version number of the EGLimplementation will be returned as elements 0 and 1. May benull. true if the operation succeeds.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if major_minor isnon-null but has length less than 2.

eglMakeCurrent binds context to the current rendering thread and to the draw and read surfaces. draw is used for all GL operations except for any pixel data read back (glReadPixels, glCopyTexImage2D, and glCopyTexSubImage2D), which is taken from the frame buffer values of read.

If the calling thread has already a current rendering context, that context is flushed and marked as no longer current.

The first time that context is made current, the viewport and scissor dimensions are set to the size of the draw surface. The viewport and scissor are not modified when context is subsequently made current.

To release the current context without assigning a new one, call eglMakeCurrent with draw and read set to EGL_NO_SURFACE and context set to EGL_NO_CONTEXT.

Use eglGetCurrentContext, eglGetCurrentDisplay, and eglGetCurrentSurface to query the current rendering context and associated display connection and surfaces.

Errors

false is returned on failure, true otherwise. If false is returned, the previously current rendering context and surfaces (if any) remain unchanged.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_SURFACE is generated if draw or read is not an EGL surface.

EGL_BAD_CONTEXT is generated if context is not an EGL rendering context.

EGL_BAD_MATCH is generated if draw or read are not compatible with context, or if context is set to EGL_NO_CONTEXT and draw or read are not set to EGL_NO_SURFACE, or if draw or read are set to EGL_NO_SURFACE and context is not set to EGL_NO_CONTEXT.

EGL_BAD_ACCESS is generated if context is current to some other thread.

EGL_BAD_NATIVE_PIXMAP may be generated if a native pixmap underlying either draw or read is no longer valid.

EGL_BAD_NATIVE_WINDOW may be generated if a native window underlying either draw or read is no longer valid.

EGL_BAD_CURRENT_SURFACE is generated if the previous context has unflushed commands and the previous surface is no longer valid.

EGL_BAD_ALLOC may be generated if allocation of ancillary buffers for draw or read were delayed until eglMakeCurrent is called, and there are not enough resources to allocate them.

EGL_CONTEXT_LOST (1.1 only)

A power management event has occurred. The application must destroy all contexts and reinitialise OpenGL ES state and objects to continue rendering.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  draw - Specifies the EGL draw surface.
Parameters:
  read - Specifies the EGL read surface.
Parameters:
  context - Specifies the EGL rendering context to be attachedto the surfaces.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if draw isnull.
exception:
  IllegalArgumentException - if read isnull.
exception:
  IllegalArgumentException - if context isnull. true if the operation succeeds.

eglQueryContext returns in value[0] the value of attribute for context. attribute can be one of the following:

• EGL_CONFIG_ID

Returns the ID of the EGL frame buffer configuration with respect to which the context was created.

Errors

false is returned on failure, true otherwise. value is not modified when false is returned.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_CONTEXT is generated if context is not an EGL rendering context.

EGL_BAD_ATTRIBUTE is generated if attribute is not a valid context attribute.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  context - Specifies the EGL rendering context to query.
Parameters:
  attribute - Specifies the EGL rendering context attribute tobe returned.
Parameters:
  value - Returns the requested value.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if context isnull.
exception:
  IllegalArgumentException - if value isnull or has length less than 1. true if the query succeeds.

eglQueryString returns a String describing an EGL display connection. name can be one of the following:

• EGL_VENDOR

Returns the company responsible for this EGL implementation. This name does not change from release to release.

• EGL_VERSION

Returns a version or release number. The EGL_VERSION string is laid out as follows:

major_version.minor_version space vendor_specific_info

• EGL_EXTENSIONS

Returns a space-separated list of supported extensions to EGL.

The string data returned from the native EGL implementation is converted into UTF8 format and returned as a Java String.

Errors

null is returned on failure.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_PARAMETER is generated if name is not an accepted value.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  name - Specifies a symbolic constant, one ofEGL_VENDOR, EGL_VERSION, orEGL_EXTENSIONS.
exception:
  IllegalArgumentException - if display isnull. A String containing the query result.

eglQuerySurface returns in value[0] the value of attribute for surface. attribute can be one of the following:

• EGL_CONFIG_ID

Returns the ID of the EGL frame buffer configuration with respect to which the surface was created.

• EGL_WIDTH

Returns the width of the surface in pixels.

• EGL_HEIGHT

Returns the height of the surface in pixels.

• EGL_LARGEST_PBUFFER

Returns the same attribute value specified when the surface was created with eglCreatePbufferSurface. For a window or pixmap surface, value is not modified.

• EGL_TEXTURE_FORMAT (1.1 only)

Returns format of texture. Possible values are EGL_NO_TEXTURE, EGL_TEXTURE_RGB, and EGL_TEXTURE_RGBA.

• EGL_TEXTURE_TARGET (1.1 only)

Returns type of texture. Possible values are EGL_NO_TEXTURE, or EGL_TEXTURE_2D.

• EGL_MIPMAP_TEXTURE (1.1 only)

Returns EGL_TRUE if texture has mipmaps, EGL_FALSE otherwise.

• EGL_MIPMAP_LEVEL (1.1 only)

Returns which level of the mipmap to render to, if texture has mipmaps.

1.1 Notes

Errors

false is returned on failure, true otherwise. value is not modified when false is returned.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_SURFACE is generated if surface is not an EGL surface.

EGL_BAD_ATTRIBUTE is generated if attribute is not a valid surface attribute.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  surface - Specifies the EGL surface to query.
Parameters:
  attribute - Specifies the EGL surface attribute to be returned.
Parameters:
  value - Returns the requested value.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if surface isnull.
exception:
  IllegalArgumentException - if value isnull or has length less than 1. true if the query succeeds.

If surface is a window surface, eglSwapBuffers posts its color buffer to the associated native window.

eglSwapBuffers performs an implicit glFlush before it returns. Subsequent GL commands may be issued immediately after calling eglSwapBuffers, but are not executed until the buffer exchange is completed.

If surface is a pixel buffer or a pixmap, eglSwapBuffers has no effect, and no error is generated.

Notes

The color buffer of surface is left undefined after calling eglSwapBuffers.

On the CLDC/MIDP plaform, calling eglSwapBuffers is equivalent to calling glFinish when drawing to a GameCanvas. The GameCanvas.flushGraphics method is used to copy the contents of the back buffer to the screen.

Errors

false is returned if swapping of the surface buffers fails, true otherwise.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.

EGL_NOT_INITIALIZED is generated if display has not been initialized.

EGL_BAD_SURFACE is generated if surface is not an EGL drawing surface.

EGL_CONTEXT_LOST (1.1 only)

A power management event has occurred. The application must destroy all contexts and reinitialise OpenGL ES state and objects to continue rendering.
Parameters:
  display - Specifies the EGL display connection.
Parameters:
  surface - Specifies the EGL drawing surface whose buffersare to be swapped.
exception:
  IllegalArgumentException - if display isnull.
exception:
  IllegalArgumentException - if surface isnull. true if the operation succeeds.

eglTerminate releases resources associated with an EGL display connection. Termination marks all EGL resources associated with the EGL display connection for deletion. If contexts or surfaces associated with display is current to any thread, they are not released until they are no longer current as a result of eglMakeCurrent.

Terminating an already terminated EGL display connection has no effect other than returning true. A terminated display may be re-initialized by calling eglInitialize again.

Errors

false is returned if eglTerminate fails, true otherwise.

EGL_BAD_DISPLAY is generated if display is not an EGL display connection.
Parameters:
  display - Specifies the EGL display connection to terminate.
exception:
  IllegalArgumentException - if display isnull. true if the operation succeeds.

GL rendering calls made prior to eglWaitGL are guaranteed to be executed before native rendering calls made after eglWaitGL. The same result can be achieved using glFinish.

eglWaitGL is ignored if there is no current EGL rendering context.

Errors

false is returned if eglWaitGL fails, true otherwise.

EGL_BAD_NATIVE_SURFACE is generated if the surface associated with the current context has a native window or pixmap, and that window or pixmap is no longer valid. true if the operation succeeds.

Native rendering calls made prior to eglWaitNative are guaranteed to be executed before GL rendering calls made after eglWaitNative.

eglWaitNative is ignored if there is no current EGL rendering context.

Notes

In a MIDP environment, OpenGL ES drawing to an Image, Canvas, or GameCanvas must be preceded by a call to eglWaitNative(EGL10.EGL_CORE_NATIVE_ENGINE, graphics) and followed by a call to eglWaitGL(). The bindTarget parameter must be the instance of javax.microedition.lcdui.Graphics obtained from the GameCanvas.getGraphics method (if drawing to a GameCanvas), from the Image.getGraphics() method (if drawing to a mutable Image), or the instance obtained as the parameter to the Canvas.paint method (if drawing to a Canvas).

The results of passing improper values for engine and/or bindTarget are undefined.

The results of MIDP drawing calls are undefined from the time of the call to eglWaitNative until eglWaitGL returns.

Errors

EGL_BAD_PARAMETER is generated if engine is not a recognized marking engine.

EGL_BAD_NATIVE_SURFACE is generated if the surface associated with the current context has a native window or pixmap, and that window or pixmap is no longer valid.
Parameters:
  engine - Specifies a particular marking engine to be waitedon. Must be EGL_CORE_NATIVE_ENGINE.
Parameters:
  bindTarget - the rendering target shared by the nativeengine and the EGL drawing surface. For MIDP, must be theinstance of javax.microedition.lcdui.Graphicsrepresenting the targetted Canvas, Image, orGameCanvas. true if the operation succeeds.