ADDING VISUALIZATION MODES - VERSION 1.0

Preface

In order to handle the vast range of input types Liquid is expected to, sensory data is constrained to a single format per sensor class called the output format.

The output format describes what kind of data (type) sensors from a given class should return, and how it should be formatted (constrained). Each of the supported output formats (see Output Descriptors for Developers) is visualized in a different manner.

INFO: The component-based architecture of Liquid which is suppose to allow the toolkits visualization library to be extended has not yet been fully finalized (as of version 1.0). The process of adding new visualization modes requires hard-coding the new medium into the toolkit at all levels of its hierarchy, Liquid, Liquid Device Drivers (LDD) and Liquid Client Applications (LCA).

TO ADD A NEW VISUALIZATION MODE

Before proceeding with this tutorial make sure you have finished Adding Output Formats. The process of adding a new visualization mode to the toolkits library involves 5 stages:

STAGE 1: UPDATE resetData(..)

Liquid uses the method resetData(..) to wipe the contents of the SENSOR_DATA structure it uses to facilitate the storage and transfer of sensory input. Append the necessary code to the method in order to clear the input container created in the Adding Output Formats tutorial.

resetData(..) can be located in the source file Vis.cpp of the Liquid project space, download it here.

STAGE 2: CREATE A NEW COLLECT METHOD

Liquid uses methods that start with the prefix collectXXX(..) to obtain sensor input from an LDD and store it in the respective element of a SENSOR_DATA structure.

collectXXX(..) methods can be located in the source file Vis.cpp of the Liquid project space, download it here. Consult the source code on how to fashion your own collect method.

On completion of this step add the method definition to the source file Vis.h.

STAGE 3: CREATE A NEW DRAW METHOD

Liquid uses methods that start with the prefix drawXXX(..) to visual sensor input obtained from an LDD.

drawXXX(..) methods can be located in the source file Vis.cpp of the Liquid project space, download it here. Consult the source code on how to fashion your own draw method.

The visualization mode must be drawn within a window that measures by 760 pixels on the X axis and 270 pixels on the Y axis. The window is drawn from the position (20,20).

On completion of this step add the method definition to the source file Vis.h.

INFO: A basic knowledge of the OpenGL graphics API is required in order to complete this stage.

STAGE 4: CREATE A NEW NETWORK METHOD

Liquid uses methods that start with the prefix networkXXX(..) to collect and package sensor input into a nondescript data buffer for transmission over a TCP connection.

networkXXX(..) methods can be located in the source file Network.cpp of the Liquid project space, download it here. Consult the source code on how to fashion your own collect method.

STAGE 5: UPDATE RenderSensor()

Liquid uses the method RenderSensor() to collect input from the loaded sensors using the appropriate collectXXX(..) method and render the currently selected sensors input using the respective drawXXX(..) method.

RenderSensor() can be located in the source file Main.cpp of the Liquid project space, download it here. Insert the necessary source code to make use of the newly supported output formats collect and draw methods when required by the Liquid application. Consult the source code on how this should be done.

STAGE 6: UPDATE THE OUTPUT SERVER

Liquid uses the method SensorProc(..) to run the OUTPUT server. It selects the required networkXXX(..) method when posting data to an LCA.

SensorProc(..) can be located in the source file Network.cpp of the Liquid project space, download it here. Insert the necessary source code to access the newly supported output formats network method when required by the Liquid application. Consult the source code on how this should be done.

STAGE 7: ODDS + ENDS

You have now successfully added your new visualization mode. To finish this tutorial open the LCA project space (download from here) and using a combination of the collectXXX(..) and networkXXX(..) methods write an interpreter for the data stream the OUTPUT server will send you newly supported output format in.

The necessary source code should be inserted into the method SensorProc(..) of the source file Client.cpp.

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Now you have completed this tutorial you can finish Adding Sensor Classes.

The variable names you selected to represent the constraint parameters in Adding Output Formats
should be used as the parameter names in stage 2 of the Adding Sensor Classes tutorial.

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