Version 20 (modified by romw, 6 years ago) (diff)




HTML and JavaScript have become the predominate rendering technologies on the web. Used for everything from web browsing to mobile phone applications. HTMLGfx attempts to bring HTML rendering technologies into the BOINC graphics and screensaver environment.

By providing precompiled binaries the barrier to entry is greatly reduced allowing projects to deploy customized graphics for their applications. All projects would need to supply is the HTML/CSS/JavaScript required to display something about what is going on with the currently executing job.

In theory, volunteers could even get in on the act and create graphics for whatever applications suit their interests and share them with the community. It is conceivable that projects may even hold yearly competitions to include a volunteers graphics bundle to be deployed with the project's application.

NOTE: HTMLGfx is only supported on Windows at this time.

References: Making graphics applications for BOINC

System Overview

HTMLGfx leverages existing operating system dependent libraries for rendering HTML. By leveraging the operating systems HTML renderer HTMLGfx will be able to support whatever the latest technologies the operating systems browser supports.

Design Considerations

General Constraints

Most of the constraints we will have to deal with involve dealing with how browsers deal with security related issues.

Known issues are:

Goals and Guidelines

Top level goals are:

  • Projects should only need to create HTML/CSS/JavaScript to have a fully functional graphics application.
  • Use native platforms predominate HTML rendering technology.

Development Methods

Use whatever framework/tools are required to build a customized browser-based application.

On Windows:

  • Use Visual Studio
  • Use Active Template Library

Detailed System Design


This component is responsible for creating the main frame window used for hosting the web browser control via CHTMLBrowserHost.

As part of the normal operations of the window, it should update the URL the web browser control is displaying as state changes are detected. It should also publish updated information to the JavaScript interface.

It supports whatever requirements are described for BOINC graphics applications.

Reference: Making graphics applications for BOINC


This component hosts the web browser control and exposes whatever interfaces/callbacks the control requires for logging and display purposes. As part of its creation process it creates/exposes the JavaScript interface for CHTMLBrowserWnd to use.


This component acts as the JavaScript interoperability component. It should only support single threaded access.

Configuration File

The graphics description file has the logical name of boinc_graphics.xml (its physical name should include a version number and other info). It has following structure:

    [ <default_url>filename</default_url> ]
    [ <running_url>filename</running_url> ]
    [ <suspended_url>filename</suspended_url> ]
    [ <network_suspended_url>filename</network_suspended_url> ]
    [ <exiting_url>filename</exiting_url> ]

Optional elements:

document to display if no state specific URL is defined.
document to display while the task is running.
document to display while the task is suspended.
document to display while the network is suspended.
document to display before the task exits in 5 seconds or less.

NOTE: Any file specified in the configuration file and any related support files will need to have the <copy_file/> directive included in the versions.xml file describing the application version.

Graphics Status File

It is read once a second and is generally managed via the worker applications via the boinc_write_graphics_status() BOINC API.

Reference: boinc_graphics_status.xml

State URL Selection Process

URL selection works by the following process:

    switch_to_url = default_url

    if ((status.abort_request or status.quit_request or status.no_heartbeat) and (exiting_url not empty))
        switch_to_url = exiting_url
    else if (status.suspended and (suspended_url not empty))
        switch_to_url = suspended_url
    else if (status.network_suspended and (network_suspended_url not empty))
        switch_to_url = network_suspended_url
    else if (running_url not empty)
        switch_to_url = running_url

    if ((is_vbox_job && api_port) && (switch_to_url is empty))
        switch_to_url  = "http://localhost:" + api_port + "/";

Vboxwrapper WebAPI Port

Reference: vbox_webapi.xml

Vboxwrapper Remote Desktop Port

Reference: vbox_remote_desktop.xml

JavaScript Extension on Windows

Currently HTMLGfx can pass information to the HTML DOM via the 'window.external' extension.


Name Returns Description
log(string) void Logs a message to stderrgfx.txt
debug(string) void Logs a message with a category of 'DEBUG' to stderrgfx.txt
info(string) void Logs a message with a category of 'INFO' to stderrgfx.txt
warn(string) void Logs a message with a category of 'WARNING' to stderrgfx.txt
error(string) void Logs a message with a category of 'ERROR' to stderrgfx.txt
isStateUpdated() Boolean Returns true if it is time to refresh all the state in the UI
resetStateUpdate(Boolean) void Resets the state update flag to the given value


Name Data Type Description
appName string
appVersion long
wuName string
resName string
teamName string
userName string
userCreditTotal float
userCreditAverage float
hostCreditTotal float
hostCreditAverage float
scrsaveMode Boolean Was the graphics application launched in screensaver mode
suspended Boolean Whether the task is currently suspended
networkSuspended Boolean Should the UI suspend Internet activity
exiting Boolean Should the UI prepare to exit
exitTimeout float
cpuTime float
elapsedTime float
fractionDone float
vboxJob Boolean Is this task a vboxwrapper task?
rdpPort long
apiPort long


Example of refreshing the state of various controls:

    refresh() {
        if (window.external.isStateUpdated()) {
            username = window.external.userName;
            teamname = window.external.teamName;
        fractiondone = window.external.fractionDone;

Example HTML Page

Here is a link to a working HTML page that is embedded within the HTMLGfx app in case the boinc_graphics.xml file is missing.

Reference: default_win.htm

Precompiled Binaries

On Windows: