Added in API level 3

GLSurfaceView

open class GLSurfaceView : SurfaceView, SurfaceHolder.Callback2
kotlin.Any
   ↳ android.view.View
   ↳ android.view.SurfaceView
   ↳ android.opengl.GLSurfaceView

An implementation of SurfaceView that uses the dedicated surface for displaying OpenGL rendering.

A GLSurfaceView provides the following features:

  • Manages a surface, which is a special piece of memory that can be composited into the Android view system.
  • Manages an EGL display, which enables OpenGL to render into a surface.
  • Accepts a user-provided Renderer object that does the actual rendering.
  • Renders on a dedicated thread to decouple rendering performance from the UI thread.
  • Supports both on-demand and continuous rendering.
  • Optionally wraps, traces, and/or error-checks the renderer's OpenGL calls.

Using GLSurfaceView

Typically you use GLSurfaceView by subclassing it and overriding one or more of the View system input event methods. If your application does not need to override event methods then GLSurfaceView can be used as-is. For the most part GLSurfaceView behavior is customized by calling "set" methods rather than by subclassing. For example, unlike a regular View, drawing is delegated to a separate Renderer object which is registered with the GLSurfaceView using the setRenderer(android.opengl.GLSurfaceView.Renderer) call.

Initializing GLSurfaceView

All you have to do to initialize a GLSurfaceView is call setRenderer(android.opengl.GLSurfaceView.Renderer). However, if desired, you can modify the default behavior of GLSurfaceView by calling one or more of these methods before calling setRenderer:

Specifying the android.view.Surface

By default GLSurfaceView will create a PixelFormat.RGB_888 format surface. If a translucent surface is required, call getHolder().setFormat(PixelFormat.TRANSLUCENT). The exact format of a TRANSLUCENT surface is device dependent, but it will be a 32-bit-per-pixel surface with 8 bits per component.

Choosing an EGL Configuration

A given Android device may support multiple EGLConfig rendering configurations. The available configurations may differ in how many channels of data are present, as well as how many bits are allocated to each channel. Therefore, the first thing GLSurfaceView has to do when starting to render is choose what EGLConfig to use.

By default GLSurfaceView chooses a EGLConfig that has an RGB_888 pixel format, with at least a 16-bit depth buffer and no stencil.

If you would prefer a different EGLConfig you can override the default behavior by calling one of the setEGLConfigChooser methods.

Debug Behavior

You can optionally modify the behavior of GLSurfaceView by calling one or more of the debugging methods setDebugFlags(int), and setGLWrapper. These methods may be called before and/or after setRenderer, but typically they are called before setRenderer so that they take effect immediately.

Setting a Renderer

Finally, you must call setRenderer to register a Renderer. The renderer is responsible for doing the actual OpenGL rendering.

Rendering Mode

Once the renderer is set, you can control whether the renderer draws continuously or on-demand by calling setRenderMode. The default is continuous rendering.

Activity Life-cycle

A GLSurfaceView must be notified when to pause and resume rendering. GLSurfaceView clients are required to call onPause() when the activity stops and onResume() when the activity starts. These calls allow GLSurfaceView to pause and resume the rendering thread, and also allow GLSurfaceView to release and recreate the OpenGL display.

Handling events

To handle an event you will typically subclass GLSurfaceView and override the appropriate method, just as you would with any other View. However, when handling the event, you may need to communicate with the Renderer object that's running in the rendering thread. You can do this using any standard Java cross-thread communication mechanism. In addition, one relatively easy way to communicate with your renderer is to call queueEvent(java.lang.Runnable). For example:

class MyGLSurfaceView extends GLSurfaceView {
 
      private MyRenderer mMyRenderer;
 
      public void start() {
          mMyRenderer = ...;
          setRenderer(mMyRenderer);
      }
 
      public boolean onKeyDown(int keyCode, KeyEvent event) {
          if (keyCode == KeyEvent.KEYCODE_DPAD_CENTER) {
              queueEvent(new Runnable() {
                  // This method will be called on the rendering
                  // thread:
                  public void run() {
                      mMyRenderer.handleDpadCenter();
                  }});
              return true;
          }
          return super.onKeyDown(keyCode, event);
      }
  }
  

Summary

Nested classes
abstract

An interface for choosing an EGLConfig configuration from a list of potential configurations.

abstract

An interface for customizing the eglCreateContext and eglDestroyContext calls.

abstract

An interface for customizing the eglCreateWindowSurface and eglDestroySurface calls.

abstract

An interface used to wrap a GL interface.

abstract

A generic renderer interface.

Inherited XML attributes
Constants
static Int

Check glError() after every GL call and throw an exception if glError indicates that an error has occurred.

static Int

Log GL calls to the system log at "verbose" level with tag "GLSurfaceView".

static Int

The renderer is called continuously to re-render the scene.

static Int

The renderer only renders when the surface is created, or when requestRender is called.

Inherited constants
Public constructors

Standard View constructor.

GLSurfaceView(context: Context!, attrs: AttributeSet!)

Standard View constructor.

Public methods
open Int

Get the current value of the debug flags.

open Boolean

open Int

Get the current rendering mode.

open Unit

Pause the rendering thread, optionally tearing down the EGL context depending upon the value of setPreserveEGLContextOnPause(boolean).

open Unit

Resumes the rendering thread, re-creating the OpenGL context if necessary.

open Unit

Queue a runnable to be run on the GL rendering thread.

open Unit

Request that the renderer render a frame.

open Unit
setDebugFlags(debugFlags: Int)

Set the debug flags to a new value.

open Unit

Install a custom EGLConfigChooser.

open Unit

Install a config chooser which will choose a config as close to 16-bit RGB as possible, with or without an optional depth buffer as close to 16-bits as possible.

open Unit
setEGLConfigChooser(redSize: Int, greenSize: Int, blueSize: Int, alphaSize: Int, depthSize: Int, stencilSize: Int)

Install a config chooser which will choose a config with at least the specified depthSize and stencilSize, and exactly the specified redSize, greenSize, blueSize and alphaSize.

open Unit

Inform the default EGLContextFactory and default EGLConfigChooser which EGLContext client version to pick.

open Unit

Install a custom EGLContextFactory.

open Unit

Install a custom EGLWindowSurfaceFactory.

open Unit

Set the glWrapper.

open Unit

Control whether the EGL context is preserved when the GLSurfaceView is paused and resumed.

open Unit
setRenderMode(renderMode: Int)

Set the rendering mode.

open Unit

Set the renderer associated with this view.

open Unit
surfaceChanged(holder: SurfaceHolder, format: Int, w: Int, h: Int)

This method is part of the SurfaceHolder.

open Unit

This method is part of the SurfaceHolder.

open Unit

This method is part of the SurfaceHolder.

open Unit

This method is part of the SurfaceHolder.

open Unit

This method is part of the SurfaceHolder.

Protected methods
open Unit

open Unit

This method is used as part of the View class and is not normally called or subclassed by clients of GLSurfaceView.

open Unit

Inherited functions
Inherited properties

Constants

DEBUG_CHECK_GL_ERROR

Added in API level 3
static val DEBUG_CHECK_GL_ERROR: Int

Check glError() after every GL call and throw an exception if glError indicates that an error has occurred. This can be used to help track down which OpenGL ES call is causing an error.

Value: 1

DEBUG_LOG_GL_CALLS

Added in API level 3
static val DEBUG_LOG_GL_CALLS: Int

Log GL calls to the system log at "verbose" level with tag "GLSurfaceView".

Value: 2

RENDERMODE_CONTINUOUSLY

Added in API level 3
static val RENDERMODE_CONTINUOUSLY: Int

The renderer is called continuously to re-render the scene.

Value: 1

RENDERMODE_WHEN_DIRTY

Added in API level 3
static val RENDERMODE_WHEN_DIRTY: Int

The renderer only renders when the surface is created, or when requestRender is called.

Value: 0

Public constructors

GLSurfaceView

Added in API level 3
GLSurfaceView(context: Context!)

Standard View constructor. In order to render something, you must call setRenderer to register a renderer.

GLSurfaceView

Added in API level 3
GLSurfaceView(
    context: Context!,
    attrs: AttributeSet!)

Standard View constructor. In order to render something, you must call setRenderer to register a renderer.

Public methods

getDebugFlags

Added in API level 3
open fun getDebugFlags(): Int

Get the current value of the debug flags.

Return
Int the current value of the debug flags.

getPreserveEGLContextOnPause

Added in API level 11
open fun getPreserveEGLContextOnPause(): Boolean
Return
Boolean true if the EGL context will be preserved when paused

getRenderMode

Added in API level 3
open fun getRenderMode(): Int

Get the current rendering mode. May be called from any thread. Must not be called before a renderer has been set.

Return
Int the current rendering mode.

onPause

Added in API level 3
open fun onPause(): Unit

Pause the rendering thread, optionally tearing down the EGL context depending upon the value of setPreserveEGLContextOnPause(boolean). This method should be called when it is no longer desirable for the GLSurfaceView to continue rendering, such as in response to Activity.onStop. Must not be called before a renderer has been set.

onResume

Added in API level 3
open fun onResume(): Unit

Resumes the rendering thread, re-creating the OpenGL context if necessary. It is the counterpart to onPause(). This method should typically be called in Activity.onStart. Must not be called before a renderer has been set.

queueEvent

Added in API level 3
open fun queueEvent(r: Runnable!): Unit

Queue a runnable to be run on the GL rendering thread. This can be used to communicate with the Renderer on the rendering thread. Must not be called before a renderer has been set.

Parameters
r Runnable!: the runnable to be run on the GL rendering thread.

requestRender

Added in API level 3
open fun requestRender(): Unit

Request that the renderer render a frame. This method is typically used when the render mode has been set to RENDERMODE_WHEN_DIRTY, so that frames are only rendered on demand. May be called from any thread. Must not be called before a renderer has been set.

setDebugFlags

Added in API level 3
open fun setDebugFlags(debugFlags: Int): Unit

Set the debug flags to a new value. The value is constructed by OR-together zero or more of the DEBUG_CHECK_* constants. The debug flags take effect whenever a surface is created. The default value is zero.

Parameters
debugFlags Int: the new debug flags

setEGLConfigChooser

Added in API level 3
open fun setEGLConfigChooser(configChooser: GLSurfaceView.EGLConfigChooser!): Unit

Install a custom EGLConfigChooser.

If this method is called, it must be called before setRenderer(android.opengl.GLSurfaceView.Renderer) is called.

If no setEGLConfigChooser method is called, then by default the view will choose an EGLConfig that is compatible with the current android.view.Surface, with a depth buffer depth of at least 16 bits.

Parameters
configChooser GLSurfaceView.EGLConfigChooser!:

setEGLConfigChooser

Added in API level 3
open fun setEGLConfigChooser(needDepth: Boolean): Unit

Install a config chooser which will choose a config as close to 16-bit RGB as possible, with or without an optional depth buffer as close to 16-bits as possible.

If this method is called, it must be called before setRenderer(android.opengl.GLSurfaceView.Renderer) is called.

If no setEGLConfigChooser method is called, then by default the view will choose an RGB_888 surface with a depth buffer depth of at least 16 bits.

Parameters
needDepth Boolean:

setEGLConfigChooser

Added in API level 3
open fun setEGLConfigChooser(
    redSize: Int,
    greenSize: Int,
    blueSize: Int,
    alphaSize: Int,
    depthSize: Int,
    stencilSize: Int
): Unit

Install a config chooser which will choose a config with at least the specified depthSize and stencilSize, and exactly the specified redSize, greenSize, blueSize and alphaSize.

If this method is called, it must be called before setRenderer(android.opengl.GLSurfaceView.Renderer) is called.

If no setEGLConfigChooser method is called, then by default the view will choose an RGB_888 surface with a depth buffer depth of at least 16 bits.

setEGLContextClientVersion

Added in API level 8
open fun setEGLContextClientVersion(version: Int): Unit

Inform the default EGLContextFactory and default EGLConfigChooser which EGLContext client version to pick.

Use this method to create an OpenGL ES 2.0-compatible context. Example:

public MyView(Context context) {
          super(context);
          setEGLContextClientVersion(2); // Pick an OpenGL ES 2.0 context.
          setRenderer(new MyRenderer());
      }
  

Note: Activities which require OpenGL ES 2.0 should indicate this by setting @lt;uses-feature android:glEsVersion="0x00020000" /> in the activity's AndroidManifest.xml file.

If this method is called, it must be called before setRenderer(android.opengl.GLSurfaceView.Renderer) is called.

This method only affects the behavior of the default EGLContexFactory and the default EGLConfigChooser. If setEGLContextFactory(android.opengl.GLSurfaceView.EGLContextFactory) has been called, then the supplied EGLContextFactory is responsible for creating an OpenGL ES 2.0-compatible context. If setEGLConfigChooser(android.opengl.GLSurfaceView.EGLConfigChooser) has been called, then the supplied EGLConfigChooser is responsible for choosing an OpenGL ES 2.0-compatible config.

Parameters
version Int: The EGLContext client version to choose. Use 2 for OpenGL ES 2.0

setEGLContextFactory

Added in API level 5
open fun setEGLContextFactory(factory: GLSurfaceView.EGLContextFactory!): Unit

Install a custom EGLContextFactory.

If this method is called, it must be called before setRenderer(android.opengl.GLSurfaceView.Renderer) is called.

If this method is not called, then by default a context will be created with no shared context and with a null attribute list.

setEGLWindowSurfaceFactory

Added in API level 5
open fun setEGLWindowSurfaceFactory(factory: GLSurfaceView.EGLWindowSurfaceFactory!): Unit

Install a custom EGLWindowSurfaceFactory.

If this method is called, it must be called before setRenderer(android.opengl.GLSurfaceView.Renderer) is called.

If this method is not called, then by default a window surface will be created with a null attribute list.

setGLWrapper

Added in API level 3
open fun setGLWrapper(glWrapper: GLSurfaceView.GLWrapper!): Unit

Set the glWrapper. If the glWrapper is not null, its GLWrapper#wrap(GL) method is called whenever a surface is created. A GLWrapper can be used to wrap the GL object that's passed to the renderer. Wrapping a GL object enables examining and modifying the behavior of the GL calls made by the renderer.

Wrapping is typically used for debugging purposes.

The default value is null.

Parameters
glWrapper GLSurfaceView.GLWrapper!: the new GLWrapper

setPreserveEGLContextOnPause

Added in API level 11
open fun setPreserveEGLContextOnPause(preserveOnPause: Boolean): Unit

Control whether the EGL context is preserved when the GLSurfaceView is paused and resumed.

If set to true, then the EGL context may be preserved when the GLSurfaceView is paused.

Prior to API level 11, whether the EGL context is actually preserved or not depends upon whether the Android device can support an arbitrary number of EGL contexts or not. Devices that can only support a limited number of EGL contexts must release the EGL context in order to allow multiple applications to share the GPU.

If set to false, the EGL context will be released when the GLSurfaceView is paused, and recreated when the GLSurfaceView is resumed.

The default is false.

Parameters
preserveOnPause Boolean: preserve the EGL context when paused

setRenderMode

Added in API level 3
open fun setRenderMode(renderMode: Int): Unit

Set the rendering mode. When renderMode is RENDERMODE_CONTINUOUSLY, the renderer is called repeatedly to re-render the scene. When renderMode is RENDERMODE_WHEN_DIRTY, the renderer only rendered when the surface is created, or when requestRender is called. Defaults to RENDERMODE_CONTINUOUSLY.

Using RENDERMODE_WHEN_DIRTY can improve battery life and overall system performance by allowing the GPU and CPU to idle when the view does not need to be updated.

This method can only be called after setRenderer(android.opengl.GLSurfaceView.Renderer)

Parameters
renderMode Int: one of the RENDERMODE_X constants

setRenderer

Added in API level 3
open fun setRenderer(renderer: GLSurfaceView.Renderer!): Unit

Set the renderer associated with this view. Also starts the thread that will call the renderer, which in turn causes the rendering to start.

This method should be called once and only once in the life-cycle of a GLSurfaceView.

The following GLSurfaceView methods can only be called before setRenderer is called:

The following GLSurfaceView methods can only be called after setRenderer is called:

Parameters
renderer GLSurfaceView.Renderer!: the renderer to use to perform OpenGL drawing.

surfaceChanged

Added in API level 3
open fun surfaceChanged(
    holder: SurfaceHolder,
    format: Int,
    w: Int,
    h: Int
): Unit

This method is part of the SurfaceHolder.Callback interface, and is not normally called or subclassed by clients of GLSurfaceView.

Parameters
holder SurfaceHolder: The SurfaceHolder whose surface has changed. This value cannot be null.
format Int: The new PixelFormat of the surface. Value is android.graphics.PixelFormat#RGBA_8888, android.graphics.PixelFormat#RGBX_8888, android.graphics.PixelFormat#RGBA_F16, android.graphics.PixelFormat#RGBA_1010102, android.graphics.PixelFormat#RGB_888, android.graphics.PixelFormat#RGB_565, or android.graphics.PixelFormat.R_8
width The new width of the surface. Value is 0 or greater
height The new height of the surface. Value is 0 or greater

surfaceCreated

Added in API level 3
open fun surfaceCreated(holder: SurfaceHolder): Unit

This method is part of the SurfaceHolder.Callback interface, and is not normally called or subclassed by clients of GLSurfaceView.

Parameters
holder SurfaceHolder: The SurfaceHolder whose surface is being created. This value cannot be null.

surfaceDestroyed

Added in API level 3
open fun surfaceDestroyed(holder: SurfaceHolder): Unit

This method is part of the SurfaceHolder.Callback interface, and is not normally called or subclassed by clients of GLSurfaceView.

Parameters
holder SurfaceHolder: The SurfaceHolder whose surface is being destroyed. This value cannot be null.

surfaceRedrawNeeded

Added in API level 24
open fun surfaceRedrawNeeded(holder: SurfaceHolder): Unit

Deprecated: Deprecated in Java.

This method is part of the SurfaceHolder.Callback2 interface, and is not normally called or subclassed by clients of GLSurfaceView.

Parameters
holder SurfaceHolder: The SurfaceHolder whose surface has changed. This value cannot be null.

surfaceRedrawNeededAsync

Added in API level 26
open fun surfaceRedrawNeededAsync(
    holder: SurfaceHolder,
    finishDrawing: Runnable
): Unit

This method is part of the SurfaceHolder.Callback2 interface, and is not normally called or subclassed by clients of GLSurfaceView.

Parameters
holder SurfaceHolder: The SurfaceHolder which needs redrawing. This value cannot be null.
drawingFinished A runnable to signal completion. This may be invoked from any thread. This value cannot be null.

Protected methods

finalize

Added in API level 3
protected open fun finalize(): Unit
Exceptions
java.lang.Throwable the Exception raised by this method

onAttachedToWindow

Added in API level 3
protected open fun onAttachedToWindow(): Unit

This method is used as part of the View class and is not normally called or subclassed by clients of GLSurfaceView.

onDetachedFromWindow

Added in API level 3
protected open fun onDetachedFromWindow(): Unit