Transparency rgba in Gizmo

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Tue, 09/05/2023 - 11:55 am

Hello,

I am trying to create a 3D plot in which the function values f(x,y,z) correspond to the transparentness of each point. I made a rgba wave corresponding to each plotted point with the respective color and transparency values, but I have not been able to implement this in a 2D plot or gizmo. I am using Igor Pro version 9, on windows 10. Any help would be greatly appreciated. 


 

So, you have a list of red, green, blue and alpha values, and you want to, what, plot red vs green vs blue with the point there displaying that color with the associated alpha (transparency) value?

Make/O/N=(20,4) rgba = abs(enoise(1)) // gizmo colors are in the 0..1 range
// Gizmo scatters expect 3 columns, so we strip off the alpha column
Duplicate/O rgba, scatter
DeletePoints/M=1 3,1, scatter
NewGizmo
AppendToGizmo Scatter=root:scatter,name=scatter0
ModifyGizmo displayLastObject
AppendToGizmo axes=defaultAxes,name=axes0
ModifyGizmo stopUpdates
ModifyGizmo ModifyObject=scatter0,objectType=scatter,property={ scatterColorType,1}
ModifyGizmo ModifyObject=scatter0,objectType=scatter,property={ colorWave,root:rgba}
ModifyGizmo resumeUpdates

September 5, 2023 at 04:12 pm - Permalink

Sorry for the confusion. I have a list of rgba values, the RGB portion is set to magenta (or any other color), I would like to plot location (x,y,z input) vs output as a single color, but with a variable transparency. To do this I ran the following code and obtained the attached gizmo, following your example. Even though the alpha value for the color wave is specified, no transparency is included in the gizmo.

make/O/D/N= 20 Colour_1=1 
make/O/D/N= 20 Colour_2=0
make/O/D/N= 20 Colour_3=1
make/O/D/N= 20 Transparency=abs(enoise(1)) // equivalent to a probability function output spanning 0 to 1

concatenate/O {Colour_1,Colour_2,Colour_3,Transparency}, Colour_Wave
ModifyGizmo ModifyObject=scatter0,objectType=scatter,property={ colorWave,root:Colour_Wave}

 
Gizmo1.jpg

September 5, 2023 at 04:59 pm - Permalink

You mention xyz input vs output, but I don't see your x,y,z values (if they're not red,green,blue).

September 5, 2023 at 06:01 pm - Permalink

Hello Matthew,

I recommend sending your experiment to support@wavemetrics.com for a quicker response.  Looking at the information in your posts I am guessing that you have not created the right Gizmo environment for viewing transparency effects.  To learn more about it you can execute:

DisplayHelpTopic "Transparency and Translucency"

In particular, after you display your scatter object, make sure to select Gizmo Menu->Enable Transparency Blend.  This will add a few items to your display list that are required for transparency effects.  Also, it helps if you have a non-white background to discern the effect that you are looking for.

A shortcut to all of this is to display the scatter object as before and then simply execute:

ModifyGizmo Enhance

I hope this helps,

A.G.

September 6, 2023 at 08:58 am - Permalink