Dear Chris,
I'm currently in the process of loading an overlay and a VOI on a standard template in MRICroGL. I've chosen to do this to more effectively manage their visibility, as having both files as overlays didn't produce the desired visual result. I'm pleased with the outcome so far, but I do have two questions:
1. Is it possible to change the color of the VOI? I couldn't locate this option in the menu, aside from the ability to draw a VOI with RGB colors.
2. Why is the VOI not visible on the rendered brain view, although it appears in all other views (see attached)? Additionally, in the left tool window, I can only see the loaded overlay but not the VOI.
I appreciate your help!
Thank you very much,
Tammar
Drawings are special objects for MRIcroGL.
1. The color reflects the voxel intensity (e.g. 1=red, 2=blue, 3 = green, etc).
2. The drawings are not shown in the renderings. The renderings require gradient information for volumes, which is computationally expensive and therefore incompatible with interactively modifying drawings. Once the dynamic drawing stage is completed, you can always load it as a static overlay (File/AddOverlay) to view it on the rendering.
Our nascent NiiVue does allow you to customize drawing colors, and does show them in the rendering (albeit the rendering view is blank while the drawing pen is being dragged).
You can see this by changing the palette in the draw menu here:
https://niivue.github.io/niivue/features/draw.ui.html
and you can make your own custom palette by adjusting the script at the bottom of this web page:
https://niivue.github.io/niivue/features...
Thank you, Chris, for yoursuper quick response!
While I can use both of my ROIs as overlays in MRICroGL, my challenge lies in adjusting the transparency of one of them while keeping the other opaque in the render view. Specifically, I'm using these overlays to visualize connectivity results, where one ROI serves as the seed and the other as the target (activation area).
I aim to make the seed ROI appear slightly transparent (like in "image1" in light red and on top the opaqe green) while keeping the target ROI fully opaque. However, when I load them as overlays, I find it challenging to adjust the transparency of only one of them without affecting the transparency of the other or the underlying template ("image2".
I tried also "draw->advance->create overlap image" option to combine the rendered brain with the seed ROI thinking then to overlay the other ROI (target) on top of them. Unfortunately, this approach distorts the template template, and the colors are not preserved as desired ("image3").
I would appreciate any further advice or alternative methods you might suggest for achieving this visualization goal, either within MRICro or using any other tools you have in mind.
Thank you very much for your assistance!
Tammar
You will want to use the File/AddOverlay function to independently blend data. The drawing features make a lot of compromises to ensure fluid interaction for large dynamic datasets.