OpenCV.Net Scalar

[edmundchong]

For nodes such as BonVision.DrawText, there is a Color property which is OpenCV.Net Scalar. How do I create an OpenCV.Net Scalar to supply to this node?

[bruno-f-cruz]

1 - RightClick the target node you want to set the property of (in this case DrawText)
2 - Create property source
3 - Select the property (and hence the type) you want
4 - A constructor operator with generator-like logic will be added to the workflow

[edmundchong]

i was wondering if there was a way to do it more dynamically--say I wanted to adjust just Alpha based on some changing input integer? In other BonVision objects the individual attributes (ColorR, ColorG, ColorB, ColorA) are externalizable so that is possible.

thanks again!

[bruno-f-cruz]

The easiest is to probably allow bonsai to attempt to infer the constructor signature for you:

Workflow (Copy+Paste me)

<?xml version="1.0" encoding="utf-8"?>
<WorkflowBuilder Version="2.8.5"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xmlns:rx="clr-namespace:Bonsai.Reactive;assembly=Bonsai.Core"
                 xmlns:cv="clr-namespace:Bonsai.Vision;assembly=Bonsai.Vision"
                 xmlns:gl="clr-namespace:Bonsai.Shaders;assembly=Bonsai.Shaders"
                 xmlns:p1="clr-namespace:OpenCV.Net;assembly=OpenCV.Net"
                 xmlns="https://bonsai-rx.org/2018/workflow">
  <Workflow>
    <Nodes>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="IntProperty">
          <Value>255</Value>
        </Combinator>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="IntProperty">
          <Value>0</Value>
        </Combinator>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="IntProperty">
          <Value>5</Value>
        </Combinator>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="IntProperty">
          <Value>255</Value>
        </Combinator>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="rx:CombineLatest" />
      </Expression>
      <Expression xsi:type="InputMapping">
        <PropertyMappings>
          <Property Name="Color" Selector="Item1, Item2, Item3, Item4" />
        </PropertyMappings>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="cv:SolidColor">
          <cv:Size>
            <cv:Width>10</cv:Width>
            <cv:Height>10</cv:Height>
          </cv:Size>
          <cv:Depth>U8</cv:Depth>
          <cv:Channels>3</cv:Channels>
          <cv:Color>
            <cv:Val0>255</cv:Val0>
            <cv:Val1>0</cv:Val1>
            <cv:Val2>5</cv:Val2>
            <cv:Val3>255</cv:Val3>
          </cv:Color>
        </Combinator>
      </Expression>
      <Expression xsi:type="ExternalizedMapping">
        <Property Name="X" DisplayName="R" />
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="gl:CreateVector4">
          <gl:X>5</gl:X>
          <gl:Y>255</gl:Y>
          <gl:Z>255</gl:Z>
          <gl:W>15</gl:W>
        </Combinator>
      </Expression>
      <Expression xsi:type="InputMapping">
        <PropertyMappings>
          <Property Name="Value" Selector="X, Y, Z, W" />
        </PropertyMappings>
      </Expression>
      <Expression xsi:type="PropertySource" TypeArguments="cv:SolidColor,p1:Scalar">
        <MemberName>Color</MemberName>
        <Value>
          <Val0>5</Val0>
          <Val1>255</Val1>
          <Val2>255</Val2>
          <Val3>15</Val3>
        </Value>
      </Expression>
      <Expression xsi:type="PropertyMapping">
        <PropertyMappings>
          <Property Name="Color" />
        </PropertyMappings>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="cv:SolidColor">
          <cv:Size>
            <cv:Width>10</cv:Width>
            <cv:Height>10</cv:Height>
          </cv:Size>
          <cv:Depth>U8</cv:Depth>
          <cv:Channels>3</cv:Channels>
          <cv:Color>
            <cv:Val0>255</cv:Val0>
            <cv:Val1>0</cv:Val1>
            <cv:Val2>5</cv:Val2>
            <cv:Val3>255</cv:Val3>
          </cv:Color>
        </Combinator>
      </Expression>
    </Nodes>
    <Edges>
      <Edge From="0" To="4" Label="Source1" />
      <Edge From="1" To="4" Label="Source2" />
      <Edge From="2" To="4" Label="Source3" />
      <Edge From="3" To="4" Label="Source4" />
      <Edge From="4" To="5" Label="Source1" />
      <Edge From="5" To="6" Label="Source1" />
      <Edge From="7" To="8" Label="Source1" />
      <Edge From="8" To="9" Label="Source1" />
      <Edge From="9" To="10" Label="Source1" />
      <Edge From="10" To="11" Label="Source1" />
      <Edge From="11" To="12" Label="Source1" />
    </Edges>
  </Workflow>
</WorkflowBuilder>

[edmundchong]

Ah yes CreateVector4 would be perfect. Thanks again!!