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PowerShell CMatrix by Oisin Grehan 14 months ago
embed code: <script type="text/javascript" src="http://PoshCode.org/embed/2412"></script>download | new post

A pure console screen saver in the vein of the popular CMatrix x-term screensaver. PowerShell 2.0 module, see blog post: http://goo.gl/5QkI5

Set-StrictMode -off
#
# Module: PowerShell Console ScreenSaver Version 0.1
# Author: Oisin Grehan ( http://www.nivot.org )
#
# A PowerShell CMatrix-style screen saver for true-console hosts.
#
# This will not work in Micrisoft's ISE, Quest's PowerGUI or other graphical hosts.
# It should work fine in PowerShell+ from Idera which is a true console.
#
if ($host.ui.rawui.windowsize -eq $null) {
write-warning "Sorry, I only work in a true console host like powershell.exe."
throw
}
#
# Console Utility Functions
#
function New-Size {
param([int]$width, [int]$height)
new-object System.Management.Automation.Host.Size $width,$height
}
function New-Rectangle {
param(
[int]$left,
[int]$top,
[int]$right,
[int]$bottom
)
$rect = new-object System.Management.Automation.Host.Rectangle
$rect.left= $left
$rect.top = $top
$rect.right =$right
$rect.bottom = $bottom
$rect
}
function New-Coordinate {
param([int]$x, [int]$y)
new-object System.Management.Automation.Host.Coordinates $x, $y
}
function Get-BufferCell {
param([int]$x, [int]$y)
$rect = new-rectangle $x $y $x $y
[System.Management.Automation.Host.buffercell[,]]$cells = $host.ui.RawUI.GetBufferContents($rect)
$cells[0,0]
}
function Set-BufferCell {
[outputtype([System.Management.Automation.Host.buffercell])]
param(
[int]$x,
[int]$y,
[System.Management.Automation.Host.buffercell]$cell
)
$rect = new-rectangle $x $y $x $y
# return previous
get-buffercell $x $y
# use "fill" overload with single cell rect
$host.ui.rawui.SetBufferContents($rect, $cell)
}
function New-BufferCell {
param(
[string]$Character,
[consolecolor]$ForeGroundColor = $(get-buffercell 0 0).foregroundcolor,
[consolecolor]$BackGroundColor = $(get-buffercell 0 0).backgroundcolor,
[System.Management.Automation.Host.BufferCellType]$BufferCellType = "Complete"
)
$cell = new-object System.Management.Automation.Host.BufferCell
$cell.Character = $Character
$cell.ForegroundColor = $foregroundcolor
$cell.BackgroundColor = $backgroundcolor
$cell.BufferCellType = $buffercelltype
$cell
}
function log {
param($message)
[diagnostics.debug]::WriteLine($message, "PS ScreenSaver")
}
#
# Main entry point for starting the animation
#
function Start-CMatrix {
param(
[int]$maxcolumns = 8,
[int]$frameWait = 100
)
$script:winsize = $host.ui.rawui.WindowSize
$script:columns = @{} # key: xpos; value; column
$script:framenum = 0
$prevbg = $host.ui.rawui.BackgroundColor
$host.ui.rawui.BackgroundColor = "black"
cls
$done = $false
while (-not $done) {
Write-FrameBuffer -maxcolumns $maxcolumns
Show-FrameBuffer
sleep -milli $frameWait
$done = $host.ui.rawui.KeyAvailable
}
$host.ui.rawui.BackgroundColor = $prevbg
cls
}
# TODO: actually write into buffercell[,] framebuffer
function Write-FrameBuffer {
param($maxColumns)
# do we need a new column?
if ($columns.count -lt $maxcolumns) {
# incur staggering of columns with get-random
# by only adding a new one 50% of the time
if ((get-random -min 0 -max 10) -lt 5) {
# search for a column not current animating
do {
$x = get-random -min 0 -max ($winsize.width - 1)
} while ($columns.containskey($x))
$columns.add($x, (new-column $x))
}
}
$script:framenum++
}
# TODO: setbuffercontent with buffercell[,] framebuffer
function Show-FrameBuffer {
param($frame)
$completed=@()
# loop through each active column and animate a single step/frame
foreach ($entry in $columns.getenumerator()) {
$column = $entry.value
# if column has finished animating, add to the "remove" pile
if (-not $column.step()) {
$completed += $entry.key
}
}
# cannot remove from collection while enumerating, so do it here
foreach ($key in $completed) {
$columns.remove($key)
}
}
function New-Column {
param($x)
# return a new module that represents the column of letters and its state
# we also pass in a reference to the main screensaver module to be able to
# access our console framebuffer functions.
new-module -ascustomobject -name "col_$x" -script {
param(
[int]$startx,
[PSModuleInfo]$parentModule
)
$script:xpos = $startx
$script:ylimit = $host.ui.rawui.WindowSize.Height
[int]$script:head = 1
[int]$script:fade = 0
[int]$script:fadelen = [math]::Abs($ylimit / 3)
$script:fadelen += (get-random -min 0 -max $fadelen)
function Step {
# reached the bottom yet?
if ($head -lt $ylimit) {
& $parentModule Set-BufferCell $xpos $head (
& $parentModule New-BufferCell -Character `
([char](get-random -min 65 -max 122)) -Fore white) > $null
& $parentModule Set-BufferCell $xpos ($head - 1) (
& $parentModule New-BufferCell -Character `
([char](get-random -min 65 -max 122)) -Fore green) > $null
$script:head++
}
# time to start rendering the darker green "tail?"
if ($head -gt $fadelen) {
& $parentModule Set-BufferCell $xpos $fade (
& $parentModule New-BufferCell -Character `
([char](get-random -min 65 -max 122)) -Fore darkgreen) > $null
$script:fade++
}
# are we done animating?
if ($fade -lt $ylimit) {
return $true
}
$false
}
Export-ModuleMember -function Step
} -args $x, $executioncontext.sessionstate.module
}
function Start-ScreenSaver {
# feel free to tweak maxcolumns and frame delay
# currently 8 columns with 50ms wait
Start-CMatrix -max 8 -frame 50
}
function Register-Timer {
# prevent prompt from reregistering if explicit disable
if ($_ssdisabled) {
return
}
if (-not (Test-Path variable:global:_ssjob)) {
# register our counter job
$global:_ssjob = Register-ObjectEvent $_sstimer elapsed -action {
$global:_sscount++;
$global:_sssrcid = $event.sourceidentifier
# hit timeout yet?
if ($_sscount -eq $_sstimeout) {
# disable this event (prevent choppiness)
Unregister-Event -sourceidentifier $_sssrcid
Remove-Variable _ssjob -scope Global
sleep -seconds 1
# start ss
Start-ScreenSaver
}
}
}
}
function Enable-ScreenSaver {
if (-not $_ssdisabled) {
write-warning "Screensaver is not disabled."
return
}
$global:_ssdisabled = $false
}
function Disable-ScreenSaver {
if ((Test-Path variable:global:_ssjob)) {
$global:_ssdisabled = $true
Unregister-Event -SourceIdentifier $_sssrcid
Remove-Variable _ssjob -Scope global
} else {
write-warning "Screen saver is not enabled."
}
}
function Get-ScreenSaverTimeout {
new-timespan -seconds $global:_sstimeout
}
function Set-ScreenSaverTimeout {
[cmdletbinding(defaultparametersetname="int")]
param(
[parameter(position=0, mandatory=$true, parametersetname="int")]
[int]$Seconds,
[parameter(position=0, mandatory=$true, parametersetname="timespan")]
[Timespan]$Timespan
)
if ($pscmdlet.parametersetname -eq "int") {
$timespan = new-timespan -seconds $Seconds
}
if ($timespan.totalseconds -lt 1) {
throw "Timeout must be greater than 0 seconds."
}
$global:_sstimeout = $timespan.totalseconds
}
#
# Eventing / Timer Hooks, clean up and Prompt injection
#
# timeout
[int]$global:_sstimeout = 180 # default 3 minutes
# tick count
[int]$global:_sscount = 0
# modify current prompt function to reset ticks counter to 0 and
# to reregister timer, while saving for later on module onload
$self = $ExecutionContext.SessionState.Module
$function:global:prompt = $self.NewBoundScriptBlock(
[scriptblock]::create(
("{0}`n`$global:_sscount = 0`nRegister-Timer" `
-f ($global:_ssprompt = gc function:prompt))))
# configure our timer
$global:_sstimer = new-object system.timers.timer
$_sstimer.Interval = 1000 # tick once a second
$_sstimer.AutoReset = $true
$_sstimer.start()
# we start out disabled - use enable-screensaver
$global:_ssdisabled = $true
# arrange clean up on module remove
$ExecutionContext.SessionState.Module.OnRemove = {
# restore prompt
$function:global:prompt = [scriptblock]::Create($_ssprompt)
# kill off eventing subscriber, if one exists
if ($_sssrcid) {
Unregister-Event -SourceIdentifier $_sssrcid
}
# clean up timer
$_sstimer.Dispose()
# clear out globals
remove-variable _ss* -scope global
}
Export-ModuleMember -function Start-ScreenSaver, Get-ScreenSaverTimeout, `
Set-ScreenSaverTimeout, Enable-ScreenSaver, Disable-ScreenSaver

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Set-StrictMode -off

#
# Module: PowerShell Console ScreenSaver Version 0.1
# Author: Oisin Grehan ( http://www.nivot.org )
#
# A PowerShell CMatrix-style screen saver for true-console hosts.
#
# This will not work in Micrisoft's ISE, Quest's PowerGUI or other graphical hosts.
# It should work fine in PowerShell+ from Idera which is a true console.
#

if ($host.ui.rawui.windowsize -eq $null) {
    write-warning "Sorry, I only work in a true console host like powershell.exe."
    throw
}

#
# Console Utility Functions
#

function New-Size {
    param([int]$width, [int]$height)
    
    new-object System.Management.Automation.Host.Size $width,$height
}

function New-Rectangle {
    param(
        [int]$left,
        [int]$top,
        [int]$right,
        [int]$bottom
    )
    
    $rect = new-object System.Management.Automation.Host.Rectangle
    $rect.left= $left
    $rect.top = $top
    $rect.right =$right
    $rect.bottom = $bottom
    
    $rect
}

function New-Coordinate {
    param([int]$x, [int]$y)
    
    new-object System.Management.Automation.Host.Coordinates $x, $y
}

function Get-BufferCell {
    param([int]$x, [int]$y)
    
    $rect = new-rectangle $x $y $x $y
    
    [System.Management.Automation.Host.buffercell[,]]$cells = $host.ui.RawUI.GetBufferContents($rect)    
    
    $cells[0,0]
}

function Set-BufferCell {
    [outputtype([System.Management.Automation.Host.buffercell])]
    param(
        [int]$x,
        [int]$y,
        [System.Management.Automation.Host.buffercell]$cell
    )
    
    $rect = new-rectangle $x $y $x $y
        
    # return previous
    get-buffercell $x $y

    # use "fill" overload with single cell rect    
    $host.ui.rawui.SetBufferContents($rect, $cell)
}

function New-BufferCell {
    param(
        [string]$Character,
        [consolecolor]$ForeGroundColor = $(get-buffercell 0 0).foregroundcolor,
        [consolecolor]$BackGroundColor = $(get-buffercell 0 0).backgroundcolor,
        [System.Management.Automation.Host.BufferCellType]$BufferCellType = "Complete"
    )
    
    $cell = new-object System.Management.Automation.Host.BufferCell
    $cell.Character = $Character
    $cell.ForegroundColor = $foregroundcolor
    $cell.BackgroundColor = $backgroundcolor
    $cell.BufferCellType = $buffercelltype
    
    $cell
}

function log {
    param($message)
    [diagnostics.debug]::WriteLine($message, "PS ScreenSaver")
}

#
# Main entry point for starting the animation
#

function Start-CMatrix {
    param(
        [int]$maxcolumns = 8,
        [int]$frameWait = 100
    )

    $script:winsize = $host.ui.rawui.WindowSize
    $script:columns = @{} # key: xpos; value; column
    $script:framenum = 0
        
    $prevbg = $host.ui.rawui.BackgroundColor
    $host.ui.rawui.BackgroundColor = "black"
    cls
    
    $done = $false        
    
    while (-not $done) {

        Write-FrameBuffer -maxcolumns $maxcolumns

        Show-FrameBuffer
        
        sleep -milli $frameWait
        
        $done = $host.ui.rawui.KeyAvailable        
    }
    
    $host.ui.rawui.BackgroundColor = $prevbg
    cls
}

# TODO: actually write into buffercell[,] framebuffer
function Write-FrameBuffer {
    param($maxColumns)

    # do we need a new column?
    if ($columns.count -lt $maxcolumns) {
        
        # incur staggering of columns with get-random
        # by only adding a new one 50% of the time
        if ((get-random -min 0 -max 10) -lt 5) {
            
            # search for a column not current animating
            do { 
                $x = get-random -min 0 -max ($winsize.width - 1)
            } while ($columns.containskey($x))
            
            $columns.add($x, (new-column $x))
            
        }
    }
    
    $script:framenum++
}

# TODO: setbuffercontent with buffercell[,] framebuffer
function Show-FrameBuffer {
    param($frame)
    
    $completed=@()
    
    # loop through each active column and animate a single step/frame
    foreach ($entry in $columns.getenumerator()) {
        
        $column = $entry.value
    
        # if column has finished animating, add to the "remove" pile
        if (-not $column.step()) {            
            $completed += $entry.key
        }
    }
    
    # cannot remove from collection while enumerating, so do it here
    foreach ($key in $completed) {
        $columns.remove($key)
    }    
}

function New-Column {
    param($x)
    
    # return a new module that represents the column of letters and its state
    # we also pass in a reference to the main screensaver module to be able to
    # access our console framebuffer functions.
    
    new-module -ascustomobject -name "col_$x" -script {
        param(
            [int]$startx,
            [PSModuleInfo]$parentModule
         )
        
        $script:xpos = $startx
        $script:ylimit = $host.ui.rawui.WindowSize.Height

        [int]$script:head = 1
        [int]$script:fade = 0
        [int]$script:fadelen = [math]::Abs($ylimit / 3)
        
        $script:fadelen += (get-random -min 0 -max $fadelen)
        
        function Step {
            
            # reached the bottom yet?
            if ($head -lt $ylimit) {

                & $parentModule Set-BufferCell $xpos $head (
                    & $parentModule New-BufferCell -Character `
                        ([char](get-random -min 65 -max 122)) -Fore white) > $null
                
                & $parentModule Set-BufferCell $xpos ($head - 1) (
                    & $parentModule New-BufferCell -Character `
                        ([char](get-random -min 65 -max 122)) -Fore green) > $null
                
                $script:head++
            }
            
            # time to start rendering the darker green "tail?"
            if ($head -gt $fadelen) {

                & $parentModule Set-BufferCell $xpos $fade (
                    & $parentModule New-BufferCell -Character `
                        ([char](get-random -min 65 -max 122)) -Fore darkgreen) > $null
                    
                $script:fade++
            }
            
            # are we done animating?
            if ($fade -lt $ylimit) {
                return $true
            }
                        
            $false            
        }
                
        Export-ModuleMember -function Step
        
    } -args $x, $executioncontext.sessionstate.module
}

function Start-ScreenSaver {
    
    # feel free to tweak maxcolumns and frame delay
    # currently 8 columns with 50ms wait
    
    Start-CMatrix -max 8 -frame 50
}

function Register-Timer {

    # prevent prompt from reregistering if explicit disable
    if ($_ssdisabled) {
        return
    }
    
    if (-not (Test-Path variable:global:_ssjob)) {
        
        # register our counter job
        $global:_ssjob = Register-ObjectEvent $_sstimer elapsed -action {
            
            $global:_sscount++;
            $global:_sssrcid = $event.sourceidentifier
                
            # hit timeout yet?
            if ($_sscount -eq $_sstimeout) {
                
                # disable this event (prevent choppiness)
                Unregister-Event -sourceidentifier $_sssrcid
                Remove-Variable _ssjob -scope Global
                           
                sleep -seconds 1
                     
                # start ss
                Start-ScreenSaver
            }

        }
    }
}

function Enable-ScreenSaver {
    
    if (-not $_ssdisabled) {
        write-warning "Screensaver is not disabled."
        return
    }
    
    $global:_ssdisabled = $false    
}

function Disable-ScreenSaver {

    if ((Test-Path variable:global:_ssjob)) {

        $global:_ssdisabled = $true
        Unregister-Event -SourceIdentifier $_sssrcid        
        Remove-Variable _ssjob -Scope global        

    } else {
        write-warning "Screen saver is not enabled."
    }
}

function Get-ScreenSaverTimeout {
    new-timespan -seconds $global:_sstimeout
}

function Set-ScreenSaverTimeout {
    [cmdletbinding(defaultparametersetname="int")]
    param(
        [parameter(position=0, mandatory=$true, parametersetname="int")]
        [int]$Seconds,
        
        [parameter(position=0, mandatory=$true, parametersetname="timespan")]
        [Timespan]$Timespan
    )
    
    if ($pscmdlet.parametersetname -eq "int") {
        $timespan = new-timespan -seconds $Seconds
    }
    
    if ($timespan.totalseconds -lt 1) {
        throw "Timeout must be greater than 0 seconds."
    }
    
    $global:_sstimeout = $timespan.totalseconds
}

#
# Eventing / Timer Hooks, clean up and Prompt injection
#

# timeout
[int]$global:_sstimeout = 180 # default 3 minutes

# tick count
[int]$global:_sscount = 0

# modify current prompt function to reset ticks counter to 0 and
# to reregister timer, while saving for later on module onload

$self = $ExecutionContext.SessionState.Module
$function:global:prompt = $self.NewBoundScriptBlock(
    [scriptblock]::create(
        ("{0}`n`$global:_sscount = 0`nRegister-Timer" `
            -f ($global:_ssprompt = gc function:prompt))))

# configure our timer
$global:_sstimer = new-object system.timers.timer
$_sstimer.Interval = 1000 # tick once a second
$_sstimer.AutoReset = $true
$_sstimer.start()

# we start out disabled - use enable-screensaver
$global:_ssdisabled = $true

# arrange clean up on module remove
$ExecutionContext.SessionState.Module.OnRemove = { 
    
    # restore prompt
    $function:global:prompt = [scriptblock]::Create($_ssprompt)
    
    # kill off eventing subscriber, if one exists
    if ($_sssrcid) {
        Unregister-Event -SourceIdentifier $_sssrcid
    }
    
    # clean up timer
    $_sstimer.Dispose()
    
    # clear out globals
    remove-variable _ss* -scope global
}

Export-ModuleMember -function Start-ScreenSaver, Get-ScreenSaverTimeout, `
    Set-ScreenSaverTimeout, Enable-ScreenSaver, Disable-ScreenSaver

PowerShell CMatrix by Oisin Grehan 14 months ago
embed code: <script type="text/javascript" src="http://PoshCode.org/embed/2412"></script>download | new post

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PowerShell CMatrix by Oisin Grehan 14 months agoembed code: <script type="text/javascript" src="http://PoshCode.org/embed/2412"></script>download | new post

PoshCode Cmdlets

Recent Contributions

ContributeSearch

About

Community

Credits

PowerShell CMatrix by Oisin Grehan 14 months ago
embed code: <script type="text/javascript" src="http://PoshCode.org/embed/2412"></script>download | new post