Histogram Legend

[m.wilson]

Hi All, I have been trailing a very useful tool for producing heatmaps from mesh surfaces created by @AndersDeleuran.

I was wondering how a Colour Scale Legend could be produced to give greater context to what the colours are representing in regards to height deviation. Similar to the image below.

I have been trying to merge a couple of example definitions that I have found online, but have not had much success. The original GH definition is here:
GHopper_HeatMap.gh (544.7 KB)

Many thanks in advance!
Michael

[AndersDeleuran]

Hi Michael, the simplest solution (and the one in your reference image I think) is to use the native Legend component and feed it a rectangle input. I’ve quickly slapped that onto the definition I posted in the other thread:

230222_BasicSlopeAnalysis_00.gh (60.8 KB)

I’ve been using screen space legends/HUD’s myself for the past couple of years, as those work better during the design process I find. There are probably plugins for this, but the base GHPython methods I’ve been building these with can be found in this thread:

Draw To Screen Space Foreground From DrawViewportWires

Hi All, I’m experimenting with implementing DrawViewportWires in GHPython for drawing e.g. legends on top of 3D geometry generated in Grasshopper. Here’s a quick example: [2020-11-25 11_37_02-Window] The issue I’m trying to resolve is that the rectangles (drawn with Draw2dRectangle ) are drawn behind the 3D geometry that is drawn by Grasshopper (though it still appears to obscure the wires of the 3D mesh), while the text is drawn in the foreground: [2020-11-25 11_37_32-Window] Here’s a mi…

A more advanced bar chart built using the same methods can be seen here:

Grasshopper Text Dot visibility/overlap

While there might be plugins available, it’s certainly possible using scripting components. See e.g. this topic for a hack that enables one to draw 2D objects in screen space on top of the 3D viewport objects: To draw a text dot you can implement the DrawDot method. I’ve used this code pattern quite a bit recently for drawing HUDs etc. For instance the text dots and dynamic bar chart seen here: [2022-01-19_11_45_53-]

Also, are you the Michael Wilson of Dermoid fame?

[m.wilson]

Hey @AndersDeleuran,
Thanks for the pointers! I think I have one fundamental issue, that being I am running Rhinov5 (I know, so behind the times…) and I am noticing that the colour mesh component is slightly different being AHSL inputs, whereas you have AHSV inputs. My Grasshopper knowledge is pretty basic, so not entirely sure if this is the main issue…
Also, thanks for the other threads you supplied for some context, very helpful. I find usually I have simple issues to solve, but the most time consuming task is trying to find the answers online! Usually, when searching threads to find the answers to my issues, you are always involved in the conversation(s) or have done/solved something similar in the past.
And yes, this is indeed the Dermoid dude! Hehehe, the good old dayz. How have you been mate? I see you have moved on from academia. Have you completed that PHD yet?
Many thanks again mate!
Cheers,
Michael

[AndersDeleuran]

Ah yes, I missed the Rhino5 part, my bad. The HSL color space should work, I don’t see much/any difference:

You could probably also use the native Gradient component. I prefer more explicit methods for defining/generating custom gradients though. The one I wrote here might also work for you I imagine:

Gradient color input problem

Hi Martin, it’s not a solution for the specific problem, but I recently wrote this small function for generating color gradients by sampling (using linear or cosine interpolation) along an input list of colors (i.e. to get simple and explicit control, and for implementation in GHPython scripts). Might help: [2021-02-10 13_30_23-Grasshopper - 200811_BlendingColors_00 (1)] 210210_BlendingColors_00.gh (8.9 KB)

Haha, that’s amazing. Dermoid lives!! Doing alright post-academia. Never did hand in the PhD, been chipping away at it for years when I get the chance (which is less and less after parenthood/long covid). Hope you’re doing great down under

Best,

Anders