Material: Use Render Appearance for Shading

[khanh_phamWU8FK]

I have used the API to update the color in the Appearance tab. It's okay, however, the Shading color remains the old color. How can I fix this?

[jeremy_tammik]

How do you achieve the desired setting manually in the user interface?

[khanh_phamWU8FK]

Hi Jeremy,

Thanks for response. If "Use Render Appearance" is checked, whenever you change the color of Appearance, the Shading color is changed accordingly.

[jeremy_tammik]

OK, thanks; I asked the development team for you.

[GaryOrrMBI]

There's a Property for that:
[yourmaterial].UseRenderAppearanceForShading = True

see the API help: Autodesk.Revit.DB -> Material Class
-G

[jeremy_tammik]

Hi Gary, 

oh wow, thank you for picking that up!

Cheers

Jeremy

[GaryOrrMBI]

It takes a village (or in this case a "Community" 🙂 )

Looking back at the screenshot in the OP however, I'm wondering if the issue is that setting it isn't producing the desired result since the box is checked but the color is incorrect.

-G

[khanh_phamWU8FK]

Hi Gary,

Thank you, "the box is checked but the color is incorrect." => That's what I'm talking about

[jeremy_tammik]

OK, so maybe we should start from scratch. What is the problem please?

The toggle can be set both manually in the UI and programmatically in the API. Both of those methods work for setting the toggle.

Correct?

If yes:

When you set this toggle manually n the UI, it has the desired effect.

Correct?

When you set this toggle programmatically n the API, it has the desired effect.

Correct?

[khanh_phamWU8FK]

The toggle can be set both manually in the UI and programmatically in the API. Both of those methods work for setting the toggle.
=> Correct.

When you set this toggle manually n the UI, it has the desired effect.
=> Correct.

When you set this toggle programmatically n the API, it has the desired effect.
=> I did not set this toggle programmatically. It's true by default.
I've just set the Appearance color programmatically and my expectation is the Shading color will be changed to the same, but Shading color is incorrect. The result as you can see from the screenshot.

[jeremy_tammik]

I understand now and reported this to the development team.

[GaryOrrMBI · Accepted solution]

I just ran a test using the Revit 2023 API and I can confirm this behavior.

Test 1: created a new material programmatically with thisMaterial.UseRenderAppearanceForShading = False

result as expected (direct control of shading color):

Test 2: created a new material programmatically with thisMaterial.UseRenderAppearanceForShading = False,

then manually checked the box in the UI. The resulting color and transparency values were generated as usual when creating a material in the UI (the shading color being derived by a combination of the color and bitmap properties that are set in the Appearance Asset):

Test 3: created a new material programmatically with thisMaterial.UseRenderAppearanceForShading = True

The resulting color was different than that generated in test 2 (even though all properties of the Appearance Asset were identical):

Test 4: Duplicated the material created in test 3 in the UI, using the same Appearance Asset as the test 3 material:

The result was the same as test 3. Unchecked the Use Render... in the UI. Hit apply. changed the Shading color. hit apply. checked Use Render... and: the color reverted to the unexpected color in Material 3 (expected result was the resulting color in Material 2).

Test 5: Duplicated Material 1 in the UI, using the same Appearance Asset as Material 1. Checked Use Render... and the result was the same as Test 2 (the expected derived color).

Test 6: Changed the Appearance Asset in Material 3 to use the one created in test 2. The derived Shading color was the same as in Test 2 (the expected derived color).

Continued changing Appearance Assets in the different test materials between those created programmatically as well as manually duplicating those Appearance Assets and assigning them using the UI.

As a final test, I moved the setting of the material properties to later in the code (after the creation of the Appearance Asset) and...

bingo!!! we have a winner. Everything started acting as it should act.

The final result and conclusion: The bug comes in the form of an Appearance Asset that is created programmatically after the Use Render Appearance value is enabled programmatically in the Material itself. This specific combination sets the derived color value to an unexpected value that somehow becomes cached in the Appearance asset.

@khanh_phamWU8FK,

Try creating and assigning the Appearance Asset before setting the Use Render... property on the material.

-G

[khanh_phamWU8FK · Accepted solution]

Hi Garry,

The solution you suggested worked remarkably well, and I am pleased with the outcome. Thank you once again for your outstanding support.

[GaryOrrMBI]

I wouldn't actually call it a solution, more of a workaround while we hope for a solution.

One additional note:
It might not hurt (especially if duplicating a Material and/or Render Asset) to set the UseRender... property to False immediately after creating/duplicating the Material,
then create/duplicate the Appearance Asset,
then if so desired, change the UseRender... property to True.

This would help ensure that your new Appearance Asset doesn't get the "bug" to start with.

I'm making this change to my base Material creation routine now.

-G

[c_hanschen]

Hello!

khanh_phamWU8FK started the post with "used the API to update the color in the Appearance tab", that's just were I am looking for! It's easy to change all colors of the Material, but this is a Asset Color, Right?

Can you share some code how to change the Appearance color of the Asset?
(without changing to a other existing asset)

Thanks in Advance!

Chris Hanschen
LKSVDD architecten
The Netherlands

[c_hanschen]

found it at:
https://static.au-uw2-prd.autodesk.com/Class_Handout_SD124625_New_API_to_Modify_Visual_Appearance_of...

Thanks anyway!