Does anyone notice that colors in STEP models exported from FreeCAD are wrong?
I mean the case when you open them in a different program (if you import those STEPs back in FreeCAD colors would be the same).
But opened with another program, colors do not just look differently at the screen, they have different RGB values.
This problem began from FreeCAD version 0.19, and version 0.20 steel has it.
Wile using version 0.18 I did not see such a problem.
I use STEP models made in FreeCAD for my Altium Designer projects.
Here is a simple example of how it looks.
In attached picture Cubes_FreeCAD.png you can see 3 cubes as they look on the FreeCAD screen.
The RGB values for each cube are as follows:
Grey: 128, 128, 128.
Orange: 210, 120, 20.
Blue: 0, 50, 160.
Then I export all 3 cubes into STEP file and open it in Altium Designer (add them on the PCB surface).
In attached picture Cubes_AD.png you can see 2 rows of cubes. Upper one is this STEP file from FreeCAD. In the bottom row are 3 cubes made in Altium Designer directly with the same RGB values.
As you can see the colors in upper row (FreeCAD) and bottom row (AD) are altogether different.
STEP models from FreeCAD look much lighter (brighter).
In the beginning I thought that colors in STEP just got lighter (multiplied by some coefficient) keeping same relations between RGB values. But it turned out that relations are also changed. So the colors become completely different.
And similar color transformation occurs in reverse, when I import (open) in FreeCAD a STEP model exported from Altium Designer.
But in this case colors in FreeCAD, in opposite, become darker than they were in AD, RGB values are lower, and the relations between them are changed.
I do not mean "Appearance" or how they look at the screen, I mean the change of main color (which should not be changed, in my opinion). In Appearance settings this color is called "Diffuse". And that is the same color which is accessible for setting values through model parameters panel: View / Object Style / Shape Color.
Again, with FreeCAD v.0.18 I did not have such problem. STEP models from FreeCAD (opened in AD) had exactly the same colors as objects made in AD with the same RGB components values.
As I understand in import/export process there is a color override mechanism. What is it for?
I am a pretty weak user of FreeCAD, so I apologize ahead if it is not the issue of the CAD but of myself.
But if it is an issue, I am quite surprised that no one else spoke about it before.
- Cubes_FreeCAD.png (26.71 KiB) Viewed 423 times
- Cubes_AD.png (31.42 KiB) Viewed 423 times
Last edited by andr.syn
on Fri Sep 10, 2021 8:04 pm, edited 3 times in total.