Renderer.GlesRenderer

Added in 1.0.0
Deprecated in 1.1.0

abstract class Renderer.GlesRenderer : Renderer

Known direct subclasses
ListenableGlesRenderer

This class is deprecated. Use ListenableGlesRenderer2 instead

Renderer.GlesRenderer2

Watch faces that require GLES20 rendering and are able to take advantage of SharedAssets to save memory (there can be more than once instance when editing), should extend their Renderer from this class.

Known indirect subclasses
ListenableGlesRenderer2

ListenableFuture-based compatibility wrapper around Renderer.GlesRenderer's suspending methods.


Watch faces that require GLES20 rendering should extend their Renderer from this class or GlesRenderer2 if they can take advantage of SharedAssets to save memory when editing (there can be more than once WatchFace instance when editing).

A GlesRenderer is expected to be constructed on the background thread associated with WatchFaceService.getBackgroundThreadHandler inside a call to WatchFaceService.createWatchFace. All rendering is be done on the UiThread. There is a memory barrier between construction and rendering so no special threading primitives are required.

Two linked EGLContexts are created eglBackgroundThreadContext and eglUiThreadContext which are associated with background and UiThread respectively and are shared by all instances of the renderer. OpenGL objects created on (e.g. shaders and textures) can be used on the other.

If you need to make any OpenGl calls outside of render, onBackgroundThreadGlContextCreated or onUiThreadGlSurfaceCreated then you must use either runUiThreadGlCommands or runBackgroundThreadGlCommands to execute a Runnable inside of the corresponding context. Access to the GL contexts this way is necessary because GL contexts are not shared between renderers and there can be multiple watch face instances existing concurrently (e.g. headless and interactive, potentially from different watch faces if an APK contains more than one WatchFaceService). In addition most drivers do not support concurrent access.

In Java it may be easier to extend androidx.wear.watchface.ListenableGlesRenderer instead.

Summary

Nested types

Exception thrown if a GL call fails

Public constructors

@WorkerThread
GlesRenderer(
    surfaceHolder: SurfaceHolder,
    currentUserStyleRepository: CurrentUserStyleRepository,
    watchState: WatchState,
    interactiveDrawModeUpdateDelayMillis: @IntRange(from = 0, to = 60000) Long,
    eglConfigAttribList: IntArray,
    eglSurfaceAttribList: IntArray,
    eglContextAttribList: IntArray
)

Constructs a GlesRenderer, it is recommended that new code uses GlesRenderer2 instead.

Public functions

open suspend Unit

Called once a background thread when a new GL context is created on the background thread, before any subsequent calls to render.

open Unit

Called when the Renderer is destroyed.

open Unit

Called when adb shell dumpsys is invoked for the WatchFaceService, allowing the renderer to optionally record state for debugging purposes.

open suspend Unit

Called when a new GL surface is created on the UiThread, before any subsequent calls to render or in response to SurfaceHolder.Callback.surfaceChanged.

abstract Unit
@UiThread
render(zonedDateTime: ZonedDateTime)

Sub-classes should override this to implement their watch face rendering logic which should respect the current renderParameters.

abstract Unit

Sub-classes should override this to implement their watch face highlight layer rendering logic for the RenderParameters.highlightLayer aspect of renderParameters.

suspend Unit

Inside of a Mutex this function sets the GL context associated with the WatchFaceService.getBackgroundThreadHandler's looper thread as the current one, executes commands and finally unsets the GL context.

suspend Unit
runUiThreadGlCommands(commands: suspend () -> Unit)

Inside of a Mutex this function sets the UiThread GL context as the current one, executes commands and finally unsets the GL context.

Public properties

EGLContext

The GlesRenderer's background Thread EGLContext.

EGLConfig

The GlesRenderer's EGLConfig.

EGLDisplay

The GlesRenderer's EGLDisplay.

EGLContext

The GlesRenderer's UiThread EGLContext.

Inherited functions

From androidx.wear.watchface.Renderer
open Rect

This method is used for accessibility support to describe the portion of the screen containing the main clock element.

Unit

Schedules a call to either CanvasRenderer.render or GlesRenderer.render to draw the next frame.

open Unit

Called when the RenderParameters has been updated.

Unit

Posts a message to schedule a call to either CanvasRenderer.render or GlesRenderer.render to draw the next frame.

Unit

Sends a request to the system asking it to update the preview image.

open Boolean

The system periodically (at least once per minute) calls onTimeTick() to trigger a display update.

Inherited properties

From androidx.wear.watchface.Renderer
Collection<Pair<IntContentDescriptionLabel>>

Accessibility ContentDescriptionLabel for any rendered watch face elements other than the time and ComplicationSlots which are generated automatically.

@Px Float

The center x coordinate of the SurfaceHolder this Renderer renders into.

@Px Float

The center y coordinate of the SurfaceHolder this Renderer renders into.

Long

The interval in milliseconds between frames in interactive DrawModes.

RenderParameters

The current RenderParameters.

Rect

The bounds of the SurfaceHolder this Renderer renders into.

SurfaceHolder

The SurfaceHolder that renderInternal will draw into.

WatchFaceColors?

Representative WatchFaceColors which are made available to system clients via androidx.wear.watchface.client.InteractiveWatchFaceClient.OnWatchFaceColorsListener.

Public constructors

GlesRenderer

Added in 1.2.0
Deprecated in 1.2.0
@WorkerThread
GlesRenderer(
    surfaceHolder: SurfaceHolder,
    currentUserStyleRepository: CurrentUserStyleRepository,
    watchState: WatchState,
    interactiveDrawModeUpdateDelayMillis: @IntRange(from = 0, to = 60000) Long,
    eglConfigAttribList: IntArray = EGL_CONFIG_ATTRIB_LIST,
    eglSurfaceAttribList: IntArray = EGL_SURFACE_ATTRIB_LIST,
    eglContextAttribList: IntArray = EGL_CONTEXT_ATTRIB_LIST
)

Constructs a GlesRenderer, it is recommended that new code uses GlesRenderer2 instead.

Parameters
surfaceHolder: SurfaceHolder

The SurfaceHolder whose android.view.Surface will draw into.

currentUserStyleRepository: CurrentUserStyleRepository

The associated CurrentUserStyleRepository.

watchState: WatchState

The associated WatchState.

interactiveDrawModeUpdateDelayMillis: @IntRange(from = 0, to = 60000) Long

The interval in milliseconds between frames in interactive DrawModes. To render at 60hz set to 16. Note when battery is low, the frame rate will be clamped to 10fps. Watch faces are recommended to use lower frame rates if possible for better battery life. Variable frame rates can also help preserve battery life, e.g. if a watch face has a short animation once per second it can adjust the frame rate inorder to sleep when not animating.

eglConfigAttribList: IntArray = EGL_CONFIG_ATTRIB_LIST

Attributes for EGL14.eglChooseConfig. By default this selects an RGBA8888 back buffer.

eglSurfaceAttribList: IntArray = EGL_SURFACE_ATTRIB_LIST

The attributes to be passed to EGL14.eglCreateWindowSurface. By default this is empty.

eglContextAttribList: IntArray = EGL_CONTEXT_ATTRIB_LIST

The attributes to be passed to EGL14.eglCreateContext. By default this selects EGL14.EGL_CONTEXT_CLIENT_VERSION 2.

Throws
androidx.wear.watchface.Renderer.GlesRenderer.GlesException

If any GL calls fail during initialization.

Public functions

onBackgroundThreadGlContextCreated

Added in 1.0.0
Deprecated in 1.1.0
@WorkerThread
open suspend fun onBackgroundThreadGlContextCreated(): Unit

Called once a background thread when a new GL context is created on the background thread, before any subsequent calls to render. Note this function is called inside a lambda passed to runBackgroundThreadGlCommands which has synchronized access to the GL context.

If you need to override this method in java, consider using androidx.wear.watchface.ListenableGlesRenderer instead.

onDestroy

@CallSuper
open fun onDestroy(): Unit

Called when the Renderer is destroyed.

onDump

Added in 1.3.0-alpha01
Deprecated in 1.3.0-alpha01
open fun onDump(writer: PrintWriter): Unit

Called when adb shell dumpsys is invoked for the WatchFaceService, allowing the renderer to optionally record state for debugging purposes.

onUiThreadGlSurfaceCreated

Added in 1.0.0
Deprecated in 1.1.0
@UiThread
open suspend fun onUiThreadGlSurfaceCreated(width: @Px Int, height: @Px Int): Unit

Called when a new GL surface is created on the UiThread, before any subsequent calls to render or in response to SurfaceHolder.Callback.surfaceChanged. Note this function is called inside a lambda passed to runUiThreadGlCommands which has synchronized access to the GL context.

If you need to override this method in java, consider using androidx.wear.watchface.ListenableGlesRenderer instead.

Parameters
width: @Px Int

width of surface in pixels

height: @Px Int

height of surface in pixels

render

Added in 1.0.0
Deprecated in 1.1.0
@UiThread
abstract fun render(zonedDateTime: ZonedDateTime): Unit

Sub-classes should override this to implement their watch face rendering logic which should respect the current renderParameters. Please note WatchState.isAmbient may not match the RenderParameters.drawMode and should not be used to decide what to render. E.g. when editing from the companion phone while the watch is ambient, renders may be requested with DrawMode.INTERACTIVE.

Any highlights due to RenderParameters.highlightLayer should be rendered by renderHighlightLayer instead where possible. For correct behavior this function must use the supplied ZonedDateTime in favor of any other ways of getting the time.

Note this function is called inside a lambda passed to runUiThreadGlCommands which has synchronized access to the GL context.

Note also GLES20.glBlendFunc(GLES20.GL_ONE, GLES20.GL_ZERO) is called by the library before this method.

Before any calls to this function onBackgroundThreadGlContextCreated and onUiThreadGlSurfaceCreated will have been called once on their respective threads.

Parameters
zonedDateTime: ZonedDateTime

The zonedDateTime ZonedDateTime to render with

renderHighlightLayer

Added in 1.0.0
Deprecated in 1.1.0
@UiThread
abstract fun renderHighlightLayer(zonedDateTime: ZonedDateTime): Unit

Sub-classes should override this to implement their watch face highlight layer rendering logic for the RenderParameters.highlightLayer aspect of renderParameters. Typically the implementation will clear the buffer to RenderParameters.HighlightLayer.backgroundTint before rendering a transparent highlight or a solid outline around the RenderParameters.HighlightLayer.highlightedElement. This will be composited as needed on top of the results of render. For correct behavior this function must use the supplied ZonedDateTime in favor of any other ways of getting the time.

Note this function is called inside a lambda passed to runUiThreadGlCommands which has synchronized access to the GL context.

Note also GLES20.glBlendFunc(GLES20.GL_ONE, GLES20.GL_ZERO) is called by the library before this method.

Parameters
zonedDateTime: ZonedDateTime

The zonedDateTime ZonedDateTime to render with

runBackgroundThreadGlCommands

Added in 1.0.0
Deprecated in 1.1.0
@WorkerThread
suspend fun runBackgroundThreadGlCommands(commands: suspend () -> Unit): Unit

Inside of a Mutex this function sets the GL context associated with the WatchFaceService.getBackgroundThreadHandler's looper thread as the current one, executes commands and finally unsets the GL context.

Access to the GL context this way is necessary because GL contexts are not shared between renderers and there can be multiple watch face instances existing concurrently (e.g. headless and interactive, potentially from different watch faces if an APK contains more than one WatchFaceService).

NB this function is called by the library before running runBackgroundThreadGlCommands so there's no need to use this directly in client code unless you need to make GL calls outside of those methods. If you need to call this method from java, consider using androidx.wear.watchface.ListenableGlesRenderer which provides an overload taking a Runnable.

Throws
kotlin.IllegalStateException

if the calls to EGL14.eglMakeCurrent fails

runUiThreadGlCommands

Added in 1.0.0
Deprecated in 1.1.0
suspend fun runUiThreadGlCommands(commands: suspend () -> Unit): Unit

Inside of a Mutex this function sets the UiThread GL context as the current one, executes commands and finally unsets the GL context.

Access to the GL context this way is necessary because GL contexts are not shared between renderers and there can be multiple watch face instances existing concurrently (e.g. headless and interactive, potentially from different watch faces if an APK contains more than one WatchFaceService).

If you need to call this method from java, consider using androidx.wear.watchface.ListenableGlesRenderer which provides an overload taking a Runnable.

Throws
kotlin.IllegalStateException

if the calls to EGL14.eglMakeCurrent fails

Public properties

eglBackgroundThreadContext

Added in 1.0.0
Deprecated in 1.1.0
val eglBackgroundThreadContextEGLContext

The GlesRenderer's background Thread EGLContext.

eglConfig

Added in 1.0.0
Deprecated in 1.1.0
var eglConfigEGLConfig

The GlesRenderer's EGLConfig.

Throws
kotlin.UnsupportedOperationException

setEglConfig is unsupported.

eglDisplay

Added in 1.0.0
Deprecated in 1.1.0
var eglDisplayEGLDisplay

The GlesRenderer's EGLDisplay.

Throws
kotlin.UnsupportedOperationException

setEglDisplay is unsupported.

eglUiThreadContext

Added in 1.0.0
Deprecated in 1.1.0
val eglUiThreadContextEGLContext

The GlesRenderer's UiThread EGLContext. Note this not available until after WatchFaceService.createWatchFace has completed.