[Solved] How to colorize an existing Image-type asset?

[TaxiService]

(pinging @DMagic for comments as he clearly has extensive knowledge on icons like this post)

More particularly, I am trying to colorize a vessel's map icon in the tracking station or mapview scene.

Here're the codes below that I got to work but...

//You should be able to use MonoBehaviour to run the codes related to MapNode during Update()

public class CNCCommNetUI : CommNetUI
{
  MapObject m_MapObject;

  public CNCCommNetUI()
  {
    base.colorHigh = new Color(0f, 0f, 1f, 1f); // blue connections
  }
  
  protected override void Start()
  {
  	base.Start();
  	GameEvents.onPlanetariumTargetChanged.Add(OnPlanetariumTargetChanged);
  }
  
  protected override void UpdateDisplay()
  {
    base.UpdateDisplay();
    
    //attempt to access vessel's map sprite
    //m_MapObject is of MapObject class, obtained from 'private void OnPlanetariumTargetChanged(MapObject mapObject)'
    MapNode mn = m_MapObject.uiNode;
    MapNode new_mn = MapNode.Create(mn.mapObject, new Color(0f, 0f, 1f, 1f), 512, mn.Interactable, mn.Pinnable, mn.InputBlocking); // try to colorise the grey icon as blue
    m_MapObject.uiNode = new_mn;
  }
  
  private void OnPlanetariumTargetChanged(MapObject mapObject)
  {
    if (mapObject == null)
    {
    	return;
    }

    switch (mapObject.type)
    {
      case MapObject.ObjectType.Vessel:
      CNCLog.Debug("OnPlanetariumTargetChanged: Vessel: " + mapObject.vessel.vesselName);
      m_MapObject = mapObject;
      break;
    }
  }
}

The relay icon somehow turns into the different icon of an unknown type (generic?), and remains un-colorised.

The MapNode class (decompiled by VS's ILSpy addon) has a confusing maze of methods like NodeUpdate(), Terminate() etc. Does anyone know how to solve this puzzling question?

 

Edited December 16, 2016 by TaxiService

[DMagic]

The MapNode has a protected Image component, MapNode.img.

A lot of UI elements are either white or grey with the color added in later. To change that color you just need to set the color property of the Image: MapNode.img.color = ...

Since that field is protected you might need to go through the hassle of manually accessing it with the GetComponent<Image> or GetComponent(s)InChildren<Image> methods.

Sometimes Debug Stuff can be invaluable for figuring out the hierarchy of UI elements like this:

As for why it's changing to the generic map object type, I'm guessing there is something wrong with the first argument of the Create method. 

Edited December 15, 2016 by DMagic

[TaxiService]

@DMagic

Thanks for the direct-access tip and the lovely debug mod. These two lines are sufficient to recolorize an Image-type asset.

//attempt to access vessel's map sprite
Image thisImageIcon = currentMapObject.uiNode.GetComponentInChildren<Image>();
thisImageIcon.color = new Color(1f, 0f, 1f, 1f); // pink

No further action is required such as invoking an update method after the said change is applied. KSP reads this image data in real-time when drawing graphics .

Edited December 16, 2016 by TaxiService