Syphon
Instance Methods | Properties | List of all members
SyphonClient Class Reference

Inherits NSObject.

Instance Methods

(id) - initWithServerDescription:context:options:newFrameHandler:
 
(SyphonImage *) - newFrameImage
 
(void) - stop
 

Properties

CGLContextObj context
 
BOOL isValid
 
NSDictionary * serverDescription
 
BOOL hasNewFrame
 

Detailed Description

SyphonClient makes available frames from a remote SyphonServer. A client is created from a NSDictionary which describes the server. Typically this is obtained from the shared SyphonServerDirectory, or one of Syphon's notifications.

SyphonClient allows for lazy drawing by the use of a new-frame-handler. Using a handler you can perform drawing without using a timer or polling, achieving frame-accuracy with the minimum of overhead. Alternatively, if your application uses a traditional display link or timer, you can use the hasNewFrame property to make decisions about work you may need to do. Irrespective of the presence of new frames, you can draw with a SyphonClient at any time.

It is safe to access instances of this class across threads, with the usual limitatiions related to OpenGL. The calls to SyphonClient which may cause work to be done in a GL context are: -newFrameImage, -stop and -release.

Method Documentation

◆ initWithServerDescription:context:options:newFrameHandler:()

- (id) initWithServerDescription: (NSDictionary *)  description
context: (CGLContextObj)  context
options: (NSDictionary *)  options
newFrameHandler: (void(^)(SyphonClient *client))  handler 

Returns a new client instance for the described server. You should check the isValid property after initialization to ensure a connection was made to the server.

Parameters
descriptionTypically acquired from the shared SyphonServerDirectory, or one of Syphon's notifications.
contextThe CGLContextObj context to create textures for.
optionsCurrently ignored. May be nil.
handlerA block which is invoked when a new frame becomes available. handler may be nil. This block may be invoked on a thread other than that on which the client was created.
Returns
A newly initialized SyphonClient object, or nil if a client could not be created.

◆ newFrameImage()

- (SyphonImage *) newFrameImage

Returns a SyphonImage representing the current output from the server. The texture associated with the image may continue to update when you draw with it, but you should not depend on that behaviour: call this method every time you wish to access the current server frame. This object may have GPU resources associated with it and you should release it as soon as you are finished drawing with it.

This method may perform work in the OpenGL context. As with any other OpenGL calls, you must ensure no other threads use the context during calls to this method.

Returns
A SyphonImage representing the live output from the server. YOU ARE RESPONSIBLE FOR RELEASING THIS OBJECT when you are finished with it.

◆ stop()

- (void) stop

Stops the client from receiving any further frames from the server. Use of this method is optional and releasing all references to the client has the same effect.

This method may perform work in the OpenGL context. As with any other OpenGL calls, you must ensure no other threads use those contexts during calls to this method.

Property Documentation

◆ context

- (CGLContextObj) context
readatomicassign

Returns the CGLContextObj associated with the client.

◆ isValid

- (BOOL) isValid
readatomicassign

A client is valid if it has a working connection to a server. Once this returns NO, the SyphonClient will not yield any further frames.

◆ serverDescription

- (NSDictionary*) serverDescription
readatomicassign

Returns a dictionary with a description of the server the client is attached to. See SyphonServerDirectory for the keys this dictionary contains

◆ hasNewFrame

- (BOOL) hasNewFrame
readatomicassign

Returns YES if the server has output a new frame since the last time newFrameImage was called for this client, NO otherwise.