/**
* Copyright 2009 Sun Microsystems, Inc. All Rights Reserved.
* Copyright 2010 JogAmp Community. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are those of the
* authors and should not be interpreted as representing official policies, either expressed
* or implied, of JogAmp Community.
*/
package com.jogamp.opengl;
/**
* <P>The base interface from which all GL profiles derive, providing
* checked conversion down to concrete profiles, access to the
* OpenGL context associated with the GL and extension/function
* availability queries as described below.</P>
*
* <P> While the APIs for vendor extensions are unconditionally
* exposed, the underlying functions may not be present. The method
* {@link #isFunctionAvailable} should be used to query the
* availability of any non-core function before it is used for the
* first time; for example,
* <code>gl.isFunctionAvailable("glProgramStringARB")</code>. On
* certain platforms (Windows in particular), the most "core"
* functionality is only OpenGL 1.1, so in theory any routines first
* exposed in OpenGL 1.2, 1.3, and 1.4, 1.5, or 2.0 as well as vendor
* extensions should all be queried. Calling an unavailable function
* will cause a {@link GLException} to be raised. </P>
*
* {@link #isExtensionAvailable} may also be used to determine whether
* a specific extension is available before calling the routines or
* using the functionality it exposes: for example,
* <code>gl.isExtensionAvailable("GL_ARB_vertex_program");</code>.
* However, in this case it is up to the end user to know which
* routines or functionality are associated with which OpenGL
* extensions. It may also be used to test for the availability of a
* particular version of OpenGL: for example,
* <code>gl.isExtensionAvailable("GL_VERSION_1_5");</code>.
*
* <P> Exceptions to the window system extension naming rules:
*
* <UL>
*
* <LI> WGL_ARB_pbuffer, WGL_ARB_pixel_format, and other
* platform-specific pbuffer functionality; the availability of
* pbuffers can be queried on Windows, X11 and Mac OS X platforms by
* querying {@link #isExtensionAvailable} with an argument of
* "GL_ARB_pbuffer" or "GL_ARB_pixel_format".</LI>
*
* </UL> <P>
*
*/
public interface GLBase {
/**
* Indicates whether this GL object conforms to any of the OpenGL profiles.
*/
public boolean isGL();
/**
* Indicates whether this GL object conforms to the OpenGL ≥ 4.0 compatibility profile.
* The GL4 compatibility profile includes the GL2, GL2ES1, GL2ES2, GL3, GL3bc and GL4 profile.
* @see GLContext#isGL4bc()
*/
public boolean isGL4bc();
/**
* Indicates whether this GL object conforms to the OpenGL ≥ 4.0 core profile.
* The GL4 core profile includes the GL2ES2, and GL3 profile.
* @see GLContext#isGL4()
*/
public boolean isGL4();
/**
* Indicates whether this GL object conforms to the OpenGL ≥ 3.1 compatibility profile.
* The GL3 compatibility profile includes the GL2, GL2ES1, GL2ES2 and GL3 profile.
* @see GLContext#isGL3bc()
*/
public boolean isGL3bc();
/**
* Indicates whether this GL object conforms to the OpenGL ≥ 3.1 core profile.
* The GL3 core profile includes the GL2ES2 profile.
* @see GLContext#isGL3()
*/
public boolean isGL3();
/**
* Indicates whether this GL object conforms to the OpenGL ≤ 3.0 profile.
* The GL2 profile includes the GL2ES1 and GL2ES2 profile.
* @see GLContext#isGL2()
*/
public boolean isGL2();
/**
* Indicates whether this GL object conforms to the OpenGL ES ≥ 1.0 profile.
* @see GLContext#isGLES1()
*/
public boolean isGLES1();
/**
* Indicates whether this GL object conforms to the OpenGL ES ≥ 2.0 profile.
* <p>
* Remark: ES2 compatible desktop profiles are not included.
* To query whether core ES2 functionality is provided, use {@link #isGLES2Compatible()}.
* </p>
* @see #isGLES2Compatible()
* @see GLContext#isGLES2()
*/
public boolean isGLES2();
/**
* Indicates whether this GL object conforms to the OpenGL ES ≥ 3.0 profile.
* <p>
* Remark: ES3 compatible desktop profiles are not included.
* To query whether core ES3 functionality is provided, use {@link #isGLES3Compatible()}.
* </p>
* @see #isGLES3Compatible()
* @see GLContext#isGLES3()
*/
public boolean isGLES3();
/**
* Indicates whether this GL object conforms to one of the OpenGL ES profiles,
* see {@link #isGLES1()}, {@link #isGLES2()} and {@link #isGLES3()}.
* @see GLContext#isGLES()
*/
public boolean isGLES();
/**
* Indicates whether this GL object conforms to a GL2ES1 compatible profile.
* @see GLContext#isGL2ES1()
*/
public boolean isGL2ES1();
/**
* Indicates whether this GL object conforms to a GL2ES2 compatible profile.
* @see GLContext#isGL2ES2()
*/
public boolean isGL2ES2();
/**
* Indicates whether this GL object conforms to a either a GL2GL3 or GL3ES3 compatible profile.
* @see GLContext#isGL2ES3()
*/
public boolean isGL2ES3();
/**
* Indicates whether this GL object conforms to a GL3ES3 compatible profile.
* @see GLContext#isGL3ES3()
*/
public boolean isGL3ES3();
/**
* Returns true if this GL object conforms to a GL4ES3 compatible profile, i.e. if {@link #isGLES3Compatible()} returns true.
* <p>Includes [ GL ≥ 4.3, GL ≥ 3.1 w/ GL_ARB_ES3_compatibility and GLES3 ]</p>
* @see GLContext#isGL4ES3()
*/
public boolean isGL4ES3();
/**
* Indicates whether this GL object conforms to a GL2GL3 compatible profile.
* @see GLContext#isGL2GL3()
*/
public boolean isGL2GL3();
/**
* Indicates whether this GL object uses a GL4 core profile. <p>Includes [ GL4 ].</p>
* @see GLContext#isGL4core()
*/
public boolean isGL4core();
/**
* Indicates whether this GL object uses a GL3 core profile. <p>Includes [ GL4, GL3 ].</p>
* @see GLContext#isGL3core()
*/
public boolean isGL3core();
/**
* Indicates whether this GL object uses a GL core profile. <p>Includes [ GL4, GL3, GLES3, GL2ES2 ].</p>
* @see GLContext#isGLcore()
*/
public boolean isGLcore();
/**
* Indicates whether this GL object is compatible with the core OpenGL ES2 functionality.
* @return true if this context is an ES2 context or implements
* the extension <code>GL_ARB_ES2_compatibility</code>, otherwise false
* @see GLContext#isGLES2Compatible()
*/
public boolean isGLES2Compatible();
/**
* Indicates whether this GL object is compatible with the core OpenGL ES3 functionality.
* <p>
* Return true if the underlying context is an ES3 context or implements
* the extension <code>GL_ARB_ES3_compatibility</code>, otherwise false.
* </p>
* <p>
* Includes [ GL ≥ 4.3, GL ≥ 3.1 w/ GL_ARB_ES3_compatibility and GLES3 ]
* </p>
* @see GLContext#isGLES3Compatible()
*/
public boolean isGLES3Compatible();
/**
* Indicates whether this GL object is compatible with the core OpenGL ES3.1 functionality.
* <p>
* Return true if the underlying context is an ES3 context ≥ 3.1 or implements
* the extension <code>GL_ARB_ES3_1_compatibility</code>, otherwise false.
* </p>
* <p>
* Includes [ GL ≥ 4.5, GL ≥ 3.1 w/ GL_ARB_ES3_1_compatibility and GLES3 ≥ 3.1 ]
* </p>
* @see GLContext#isGLES31Compatible()
*/
public boolean isGLES31Compatible();
/**
* Indicates whether this GL object is compatible with the core OpenGL ES3.2 functionality.
* <p>
* Return true if the underlying context is an ES3 context ≥ 3.2 or implements
* the extension <code>GL_ARB_ES3_2_compatibility</code>, otherwise false.
* </p>
* <p>
* Includes [ GL ≥ 4.5, GL ≥ 3.1 w/ GL_ARB_ES3_2_compatibility and GLES3 ≥ 3.2 ]
* </p>
* @see GLContext#isGLES32Compatible()
*/
public boolean isGLES32Compatible();
/**
* Indicates whether this GL object supports GLSL.
* @see GLContext#hasGLSL()
*/
public boolean hasGLSL();
/**
* Returns the downstream GL instance in case this is a wrapping pipeline, otherwise <code>null</code>.
* <p>
* See {@link #getRootGL()} for retrieving the implementing root instance.
* </p>
* @throws GLException if the downstream instance is not null and not a GL implementation
* @see #getRootGL()
*/
public GL getDownstreamGL() throws GLException;
/**
* Returns the implementing root instance, considering a wrapped pipelined hierarchy, see {@link #getDownstreamGL()}.
* <p>
* If this instance is not a wrapping pipeline, i.e. has no downstream instance,
* this instance is returned.
* </p>
* @throws GLException if the root instance is not a GL implementation
*/
public GL getRootGL() throws GLException;
/**
* Casts this object to the GL interface.
* @throws GLException if this object is not a GL implementation
*/
public GL getGL() throws GLException;
/**
* Casts this object to the GL4bc interface.
* @throws GLException if this object is not a GL4bc implementation
*/
public GL4bc getGL4bc() throws GLException;
/**
* Casts this object to the GL4 interface.
* @throws GLException if this object is not a GL4 implementation
*/
public GL4 getGL4() throws GLException;
/**
* Casts this object to the GL3bc interface.
* @throws GLException if this object is not a GL3bc implementation
*/
public GL3bc getGL3bc() throws GLException;
/**
* Casts this object to the GL3 interface.
* @throws GLException if this object is not a GL3 implementation
*/
public GL3 getGL3() throws GLException;
/**
* Casts this object to the GL2 interface.
* @throws GLException if this object is not a GL2 implementation
*/
public GL2 getGL2() throws GLException;
/**
* Casts this object to the GLES1 interface.
* @throws GLException if this object is not a GLES1 implementation
*/
public GLES1 getGLES1() throws GLException;
/**
* Casts this object to the GLES2 interface.
* @throws GLException if this object is not a GLES2 implementation
*/
public GLES2 getGLES2() throws GLException;
/**
* Casts this object to the GLES3 interface.
* @throws GLException if this object is not a GLES3 implementation
*/
public GLES3 getGLES3() throws GLException;
/**
* Casts this object to the GL2ES1 interface.
* @throws GLException if this object is not a GL2ES1 implementation
*/
public GL2ES1 getGL2ES1() throws GLException;
/**
* Casts this object to the GL2ES2 interface.
* @throws GLException if this object is not a GL2ES2 implementation
*/
public GL2ES2 getGL2ES2() throws GLException;
/**
* Casts this object to the GL2ES3 interface.
* @throws GLException if this object is not a GL2ES3 implementation
*/
public GL2ES3 getGL2ES3() throws GLException;
/**
* Casts this object to the GL3ES3 interface.
* @throws GLException if this object is not a GL3ES3 implementation
*/
public GL3ES3 getGL3ES3() throws GLException;
/**
* Casts this object to the GL4ES3 interface.
* @throws GLException if this object is not a GL4ES3 implementation
*/
public GL4ES3 getGL4ES3() throws GLException;
/**
* Casts this object to the GL2GL3 interface.
* @throws GLException if this object is not a GL2GL3 implementation
*/
public GL2GL3 getGL2GL3() throws GLException;
/**
* Returns the GLProfile associated with this GL object.
*/
public GLProfile getGLProfile();
/**
* Returns the GLContext associated which this GL object.
*/
public GLContext getContext();
/**
* Returns true if the specified OpenGL core- or extension-function can be
* used successfully through this GL instance given the current host (OpenGL
* <i>client</i>) and display (OpenGL <i>server</i>) configuration.<P>
* By "successfully" we mean that the function is both <i>callable</i>
* on the machine running the program and <i>available</i> on the current
* display.<P>
*
* In order to call a function successfully, the function must be both
* <i>callable</i> on the machine running the program and <i>available</i> on
* the display device that is rendering the output (note: on non-networked,
* single-display machines these two conditions are identical; on networked and/or
* multi-display machines this becomes more complicated). These conditions are
* met if the function is either part of the core OpenGL version supported by
* both the host and display, or it is an OpenGL extension function that both
* the host and display support. <P>
*
* A GL function is <i>callable</i> if it is successfully linked at runtime,
* hence the GLContext must be made current at least once.
*
* @param glFunctionName the name of the OpenGL function (e.g., use
* "glBindRenderbufferEXT" or "glBindRenderbuffer" to check if {@link
* GL#glBindRenderbuffer(int,int)} is available).
*/
public boolean isFunctionAvailable(String glFunctionName);
/**
* Returns true if the specified OpenGL extension can be
* used successfully through this GL instance given the current host (OpenGL
* <i>client</i>) and display (OpenGL <i>server</i>) configuration.<P>
*
* @param glExtensionName the name of the OpenGL extension (e.g.,
* "GL_ARB_vertex_program").
*/
public boolean isExtensionAvailable(String glExtensionName);
/**
* Returns <code>true</code> if basic FBO support is available, otherwise <code>false</code>.
* <p>
* Basic FBO is supported if the context is either GL-ES >= 2.0, GL >= 3.0 [core, compat] or implements the extensions
* <code>GL_ARB_ES2_compatibility</code>, <code>GL_ARB_framebuffer_object</code>, <code>GL_EXT_framebuffer_object</code> or <code>GL_OES_framebuffer_object</code>.
* </p>
* <p>
* Basic FBO support may only include one color attachment and no multisampling,
* as well as limited internal formats for renderbuffer.
* </p>
* @see GLContext#hasBasicFBOSupport()
*/
public boolean hasBasicFBOSupport();
/**
* Returns <code>true</code> if full FBO support is available, otherwise <code>false</code>.
* <p>
* Full FBO is supported if the context is either GL >= core 3.0 [ES, core, compat] or implements the extensions
* <code>ARB_framebuffer_object</code>, or all of
* <code>EXT_framebuffer_object</code>, <code>EXT_framebuffer_multisample</code>,
* <code>EXT_framebuffer_blit</code>, <code>GL_EXT_packed_depth_stencil</code>.
* </p>
* <p>
* Full FBO support includes multiple color attachments and multisampling.
* </p>
* @see GLContext#hasFullFBOSupport()
*/
public boolean hasFullFBOSupport();
/**
* Returns the maximum number of FBO RENDERBUFFER samples
* if {@link #hasFullFBOSupport() full FBO is supported}, otherwise false.
* @see GLContext#getMaxRenderbufferSamples()
*/
public int getMaxRenderbufferSamples();
/**
* Returns true if the GL context supports non power of two (NPOT) textures,
* otherwise false.
* <p>
* NPOT textures are supported in OpenGL >= 3, GLES2 or if the
* 'GL_ARB_texture_non_power_of_two' extension is available.
* </p>
*/
public boolean isNPOTTextureAvailable();
public boolean isTextureFormatBGRA8888Available();
/**
* Set the swap interval of the current context and attached <i>onscreen {@link GLDrawable}</i>.
* <p>
* <i>offscreen {@link GLDrawable}</i> are ignored and {@code false} is returned.
* </p>
* <p>
* The {@code interval} semantics:
* <ul>
* <li><i>0</i> disables the vertical synchronization</li>
* <li><i>≥1</i> is the number of vertical refreshes before a swap buffer occurs</li>
* <li><i><0</i> enables <i>late swaps to occur without synchronization to the video frame</i>, a.k.a <i>EXT_swap_control_tear</i>.
* If supported, the absolute value is the minimum number of
* video frames between buffer swaps. If not supported, the absolute value is being used, see above.
* </li>
* </ul>
* </p>
* @param interval see above
* @return true if the operation was successful, otherwise false
* @throws GLException if the context is not current.
* @see GLContext#setSwapInterval(int)
* @see #getSwapInterval()
*/
public void setSwapInterval(int interval) throws GLException;
/**
* Return the current swap interval.
* <p>
* If the context has not been made current at all,
* the default value {@code 0} is returned.
* </p>
* <p>
* For a valid context w/ an <o>onscreen {@link GLDrawable}</i> the default value is {@code 1},
* otherwise the default value is {@code 0}.
* </p>
* @see GLContext#getSwapInterval()
* @see #setSwapInterval(int)
*/
public int getSwapInterval();
/**
* Returns an object through which platform-specific OpenGL extensions
* (EGL, GLX, WGL, etc.) may be accessed. The data type of the returned
* object and its associated capabilities are undefined. Most
* applications will never need to call this method. It is highly
* recommended that any applications which do call this method perform
* all accesses on the returned object reflectively to guard
* themselves against changes to the implementation.
*/
public Object getPlatformGLExtensions();
/**
* Returns an object providing access to the specified OpenGL
* extension. This is intended to provide a mechanism for vendors who
* wish to provide access to new OpenGL extensions without changing
* the public API of the core package. For example, a user may request
* access to extension "GL_VENDOR_foo" and receive back an object
* which implements a vendor-specified interface which can call the
* OpenGL extension functions corresponding to that extension. It is
* up to the vendor to specify both the extension name and Java API
* for accessing it, including which class or interface contains the
* functions.
*
* <p>
* Note: it is the intent to add new extensions as quickly as possible
* to the core GL API. Therefore it is unlikely that most vendors will
* use this extension mechanism, but it is being provided for
* completeness.
* </p>
*/
public Object getExtension(String extensionName);
/** Aliased entrypoint of <code> void {@native glClearDepth}(GLclampd depth); </code> and <code> void {@native glClearDepthf}(GLclampf depth); </code>. */
public void glClearDepth( double depth );
/** Aliased entrypoint of <code> void {@native glDepthRange}(GLclampd depth); </code> and <code> void {@native glDepthRangef}(GLclampf depth); </code>. */
public void glDepthRange(double zNear, double zFar);
/**
* @param target a GL buffer (VBO) target as used in {@link GL#glBindBuffer(int, int)}, ie {@link GL#GL_ELEMENT_ARRAY_BUFFER}, {@link GL#GL_ARRAY_BUFFER}, ..
* @return the GL buffer name bound to a target via {@link GL#glBindBuffer(int, int)} or 0 if unbound.
* @see #getBufferStorage(int)
*/
public int getBoundBuffer(int target);
/**
* @param bufferName a GL buffer name, generated with e.g. {@link GL#glGenBuffers(int, int[], int)} and used in {@link GL#glBindBuffer(int, int)}, {@link GL#glBufferData(int, long, java.nio.Buffer, int)} or {@link GL2#glNamedBufferDataEXT(int, long, java.nio.Buffer, int)}.
* @return the size of the given GL buffer storage, see {@link GLBufferStorage}
* @see #getBoundBuffer(int)
*/
public GLBufferStorage getBufferStorage(int bufferName);
/**
* Returns the {@link GLBufferStorage} instance as mapped via OpenGL's native {@link GL#glMapBuffer(int, int) glMapBuffer(..)} implementation.
* <p>
* Throws a {@link GLException} if GL-function constraints are not met.
* </p>
* <p>
* {@link GL#glMapBuffer(int, int)} wrapper calls this method and returns {@link GLBufferStorage#getMappedBuffer()}.
* </p>
* <p>
* A zero {@link GLBufferStorage#getSize()} will avoid a native call and returns the unmapped {@link GLBufferStorage}.
* </p>
* <p>
* A null native mapping result indicating an error will
* not cause a GLException but returns the unmapped {@link GLBufferStorage}.
* This allows the user to handle this case.
* </p>
* @param target denotes the buffer via it's bound target
* @param access the mapping access mode
* @throws GLException if buffer is not bound to target
* @throws GLException if buffer is not tracked
* @throws GLException if buffer is already mapped
* @throws GLException if buffer has invalid store size, i.e. less-than zero
*/
public GLBufferStorage mapBuffer(int target, int access) throws GLException;
/**
* Returns the {@link GLBufferStorage} instance as mapped via OpenGL's native {@link GL#glMapBufferRange(int, long, long, int) glMapBufferRange(..)} implementation.
* <p>
* Throws a {@link GLException} if GL-function constraints are not met.
* </p>
* <p>
* {@link GL#glMapBufferRange(int, long, long, int)} wrapper calls this method and returns {@link GLBufferStorage#getMappedBuffer()}.
* </p>
* <p>
* A zero {@link GLBufferStorage#getSize()} will avoid a native call and returns the unmapped {@link GLBufferStorage}.
* </p>
* <p>
* A null native mapping result indicating an error will
* not cause a GLException but returns the unmapped {@link GLBufferStorage}.
* This allows the user to handle this case.
* </p>
* @param target denotes the buffer via it's bound target
* @param offset offset of the mapped buffer's storage
* @param length length of the mapped buffer's storage
* @param access the mapping access mode
* @throws GLException if buffer is not bound to target
* @throws GLException if buffer is not tracked
* @throws GLException if buffer is already mapped
* @throws GLException if buffer has invalid store size, i.e. less-than zero
* @throws GLException if buffer mapping range does not fit, incl. offset
*/
public GLBufferStorage mapBufferRange(final int target, final long offset, final long length, final int access) throws GLException;
/**
* @return true if a VBO is bound to {@link GL#GL_ARRAY_BUFFER} via {@link GL#glBindBuffer(int, int)}, otherwise false
*/
public boolean isVBOArrayBound();
/**
* @return true if a VBO is bound to {@link GL#GL_ELEMENT_ARRAY_BUFFER} via {@link GL#glBindBuffer(int, int)}, otherwise false
*/
public boolean isVBOElementArrayBound();
/**
* Return the framebuffer name bound to this context,
* see {@link GL#glBindFramebuffer(int, int)}.
* <p>
* Calls {@link GLContext#getBoundFramebuffer(int)}.
* </p>
*/
public int getBoundFramebuffer(int target);
/**
* Return the default draw framebuffer name.
* <p>
* May differ from it's default <code>zero</code>
* in case an framebuffer object ({@link com.jogamp.opengl.FBObject}) based drawable
* is being used.
* </p>
* <p>
* Calls {@link GLContext#getDefaultDrawFramebuffer()}.
* </p>
*/
public int getDefaultDrawFramebuffer();
/**
* Return the default read framebuffer name.
* <p>
* May differ from it's default <code>zero</code>
* in case an framebuffer object ({@link com.jogamp.opengl.FBObject}) based drawable
* is being used.
* </p>
* <p>
* Calls {@link GLContext#getDefaultReadFramebuffer()}.
* </p>
*/
public int getDefaultReadFramebuffer();
/**
* Returns the default color buffer within the current bound
* {@link #getDefaultReadFramebuffer()}, i.e. GL_READ_FRAMEBUFFER,
* which will be used as the source for pixel reading commands,
* like {@link GL#glReadPixels(int, int, int, int, int, int, java.nio.Buffer) glReadPixels} etc.
* <p>
* For offscreen framebuffer objects this is {@link GL#GL_COLOR_ATTACHMENT0},
* otherwise this is {@link GL#GL_FRONT} for single buffer configurations
* and {@link GL#GL_BACK} for double buffer configurations.
* </p>
* <p>
* Note-1: Neither ES1 nor ES2 supports selecting the read buffer via glReadBuffer
* and {@link GL#GL_BACK} is the default.
* </p>
* <p>
* Note-2: ES3 only supports {@link GL#GL_BACK}, {@link GL#GL_NONE} or {@link GL#GL_COLOR_ATTACHMENT0}+i
* </p>
* <p>
* Note-3: See {@link com.jogamp.opengl.util.GLDrawableUtil#swapBuffersBeforeRead(GLCapabilitiesImmutable) swapBuffersBeforeRead}
* for read-pixels and swap-buffers implications.
* </p>
* <p>
* Calls {@link GLContext#getDefaultReadBuffer()}.
* </p>
*/
public int getDefaultReadBuffer();
}