display results as color and opacity gradient

party colors were not really useful, when there are only two winning parties

streets.ps1

@@ -50,7 +50,12 @@ $data = Import-Csv $DataSource
 
 $greenParty = ($data[0].PSObject.Properties.Name -like '*Grüne*')[0]
 
-$partyMapping = $data | Where-Object Description -eq 'Color'
+$dataMeasure = $data.$greenParty
+| Where-Object {$_ -match '%$'}
+| ForEach-Object {$_ -replace '%$'}
+| Measure-Object -Minimum -Maximum
+$minimumResultValue = $dataMeasure.Minimum
+$maximumResultValue = $dataMeasure.Maximum
 
 # nested array instead of hashtable, because hashtable keys are case-insensitive
 $replacementList = @(
@@ -88,27 +93,21 @@ $featureList = Import-Csv ./polling_stations.csv
             $_.Formatted + "`t" + $_.Party
         }) -join "`n"
 
-        $greenResult = ($electionResultArray | Where-Object Party -eq $greenParty).ResultValue
+        $greenResultValue = ($electionResultArray | Where-Object Party -eq $greenParty).ResultValue
 
-        $opacity = ($greenResult - 20) / 5 * 0.6 + 0.4
-        $opacity = $opacity -gt 1.0 ? 1.0 : $opacity
-        $opacity = $opacity -lt 0.4 ? 0.4 : $opacity
+        $colorGreen = (($greenResultValue - $minimumResultValue) * (100 - 220)) / ($maximumResultValue - $minimumResultValue) + 220
+        $color = "rgb(0, $colorGreen, 0)"
 
-        $weight = ($greenResult - 20) / 5 * 10 + 5
-        $weight = $weight -gt 15 ? 15 : $weight
-        $weight = $weight -lt  5 ?  5 : $weight
-
-        $party = $electionResultArray[0].Party
+        $opacity = (($greenResultValue - $minimumResultValue) * (1.0 - 0.4)) / ($maximumResultValue - $minimumResultValue) + 0.4
     } else {
         $electionResultString = 'no data available'
         $opacity = 0.5
-        $party = $null
+        $color = '#ff00ff'
     }
 
     $umapOptiones = [PSCustomObject]@{
-        #color = ($using:partyMapping).$party
-        color = $partyMapping.$party ?? '#ff00ff'
-        weight = $weight
+        color = $color
+        weight = 10
         opacity = $opacity
     }