Bug 217212

Cocoa: Make WebGLLayer surface swap polymorphic to GraphicsContextGL This is needed so remote WebGL can work Currently - (void)prepareForDisplay { if (!_context) return; // To avoid running any OpenGL code in `display`, this method should be called // at the end of the rendering task. We will flush all painting commands // leaving the buffers ready to composite. #if USE(OPENGL) _context->prepareTexture(); if (_drawingBuffer) { std::swap(_contentsBuffer, _drawingBuffer); [self bindFramebufferToNextAvailableSurface]; } #elif USE(ANGLE) if (!_context->makeContextCurrent()) { // Context is likely being torn down. return; } _context->prepareTexture(); if (_drawingBuffer) { if (_latchedPbuffer) { WTF::Optional<ScopedRestoreTextureBinding> restoreBinding; // We don't need to restore GL_TEXTURE_RECTANGLE because it's not accessible from user code. if (WebCore::GraphicsContextGL::IOSurfaceTextureTarget() != WebCore::GraphicsContextGL::TEXTURE_RECTANGLE_ARB) restoreBinding.emplace(WebCore::GraphicsContextGL::IOSurfaceTextureTargetQuery(), WebCore::GraphicsContextGL::IOSurfaceTextureTarget()); GCGLenum texture = _context->platformTexture(); gl::BindTexture(WebCore::GraphicsContextGL::IOSurfaceTextureTarget(), texture); if (!EGL_ReleaseTexImage(_eglDisplay, _latchedPbuffer, EGL_BACK_BUFFER)) { // FIXME: report error. notImplemented(); } _latchedPbuffer = nullptr; } std::swap(_contentsBuffer, _drawingBuffer); std::swap(_contentsPbuffer, _drawingPbuffer); [self bindFramebufferToNextAvailableSurface]; } #endif [self setNeedsDisplay]; _preparedForDisplay = YES;