GLRenderer

GLRenderer(
    eglSpecFactory: () -> EGLSpec = { EGLSpec.V14 },
    eglConfigFactory: EGLManager.() -> EGLConfig = {
        // 8 bit channels should always be supported
        loadConfig(EGLConfigAttributes.RGBA_8888)
            ?: throw IllegalStateException("Unable to obtain config for 8 bit EGL " +
                "configuration")
    }
)

fun attach(surfaceView: SurfaceView, renderer: GLRenderer.RenderCallback): GLRenderer.RenderTarget

Adds the android.view.Surface provided by the given SurfaceView to be managed by the backing thread.

A corresponding EGLSurface is created on the GLThread as well as a callback for rendering into the surface through RenderCallback.

This method automatically configures a SurfaceHolder.Callback used to attach the android.view.Surface when the underlying SurfaceHolder that contains the surface is available. Similarly this surface will be detached from GLRenderer when the surface provided by the SurfaceView is destroyed (i.e. SurfaceHolder.Callback.surfaceDestroyed is called.

If the android.view.Surface is already available by the time this method is invoked, it is attached synchronously.

fun attach(textureView: TextureView, renderer: GLRenderer.RenderCallback): GLRenderer.RenderTarget

Adds the android.view.Surface provided by the given TextureView to be managed by the backing thread.

A corresponding EGLSurface is created on the GLThread as well as a callback for rendering into the surface through RenderCallback.

This method automatically configures a TextureView.SurfaceTextureListener used to create a android.view.Surface when the underlying SurfaceTexture is available. Similarly this surface will be detached from GLRenderer if the underlying SurfaceTexture is destroyed (i.e. TextureView.SurfaceTextureListener.onSurfaceTextureDestroyed is called.

If the SurfaceTexture is already available by the time this method is called, then it is attached synchronously.

fun attach(
    surface: Surface,
    width: Int,
    height: Int,
    renderer: GLRenderer.RenderCallback
): GLRenderer.RenderTarget

Adds the android.view.Surface to be managed by the GLThread. A corresponding EGLSurface is created on the GLThread as well as a callback for rendering into the surface through RenderCallback. Unlike the other attach methods that consume a SurfaceView or TextureView, this method does not handle any lifecycle callbacks associated with the target surface. Therefore it is up to the consumer to properly setup/teardown resources associated with this surface.

fun createRenderTarget(
    width: Int,
    height: Int,
    renderer: GLRenderer.RenderCallback
): GLRenderer.RenderTarget

Creates a new RenderTarget without a corresponding android.view.Surface. This avoids creation of an EGLSurface which is useful in scenarios where only rendering to a frame buffer object is required.

fun detach(
    target: GLRenderer.RenderTarget,
    cancelPending: Boolean,
    @WorkerThread onDetachComplete: ((GLRenderer.RenderTarget) -> Unit)? = null
): Unit

Removes the corresponding RenderTarget from management of the GLThread. This destroys the EGLSurface associated with this surface and subsequent requests to render into the surface with the provided token are ignored.

If the cancelPending flag is set to true, any queued request to render that has not started yet is cancelled. However, if this is invoked in the middle of the frame being rendered, it will continue to process the current frame.

Additionally if this flag is false, all pending requests to render will be processed before the RenderTarget is detached.

Note the detach operation will only occur if the GLRenderer is started, that is if isRunning returns true. Otherwise this is a no-op. GLRenderer will automatically detach all RenderTarget instances as part of its teardown process.

fun execute(runnable: Runnable): Unit

Queue a Runnable to be executed on the GL rendering thread. Note it is important that this Runnable does not block otherwise it can stall the GL thread. The EGLContext will be created after start is invoked and before the runnable is executed.

fun isRunning(): Boolean

Determines if the GLThread has been started. That is start has been invoked on this GLRenderer instance without a corresponding call to stop.

fun registerEGLContextCallback(callback: GLRenderer.EGLContextCallback): Unit

Add an EGLContextCallback to receive callbacks for construction and destruction of EGL dependencies.

These callbacks are invoked on the backing thread.

fun requestRender(
    target: GLRenderer.RenderTarget,
    onRenderComplete: ((GLRenderer.RenderTarget) -> Unit)? = null
): Unit

Mark the corresponding surface session with the given token as dirty to schedule a call to RenderCallback#onDrawFrame. If there is already a queued request to render into the provided surface with the specified token, this request is ignored.

Note the render operation will only occur if the GLRenderer is started, that is if isRunning returns true. Otherwise this is a no-op.

fun resize(
    target: GLRenderer.RenderTarget,
    width: Int,
    height: Int,
    onResizeComplete: ((GLRenderer.RenderTarget) -> Unit)? = null
): Unit

Resize the corresponding surface associated with the RenderTarget to the specified width and height and re-render. This will destroy the EGLSurface created by RenderCallback.onSurfaceCreated and invoke it again with the updated dimensions. An optional callback is invoked on the backing thread after the resize operation is complete.

Note the resize operation will only occur if the GLRenderer is started, that is if isRunning returns true. Otherwise this is a no-op.

fun start(name: String = "GLThread"): Unit

Starts the GLThread. After this method is called, consumers can attempt to attach android.view.Surface instances through attach as well as schedule content to be drawn through requestRender

fun stop(cancelPending: Boolean, onStop: ((GLRenderer) -> Unit)? = null): Unit

Stop the corresponding GL thread. This destroys all EGLSurfaces as well as any other EGL dependencies. All queued requests that have not been processed yet are cancelled.

Note the stop operation will only occur if the GLRenderer was previously started, that is isRunning returns true. Otherwise this is a no-op.

fun unregisterEGLContextCallback(callback: GLRenderer.EGLContextCallback): Unit

Remove EGLContextCallback to no longer receive callbacks for construction and destruction of EGL dependencies.

These callbacks are invoked on the backing thread