Appearance Assets at wrong scale

Some strange things are happening with the construction of Material Appearance Assets. I am trying to write a JPG onto a surface in Rhino, much like the _PictureFrame command in Rhino.

Is there a clue about why I need to scale my Bitmap Asset to approximate the correct scale in Revit?

In this screen shot, the final Offset and Scale dimensions for this Cutout Texture should be -0.90m & 1.8m; this matches my input (see the panel titled Actual Panel Size).
–On the right, the grasshopper side, you can see that I had to scale the input by a factor of 40 to generate a sample size of 1.83m, not quite the 1.8m I require but close enough to illustrate this question. Units in both Revit and Rhino are Meters.

Any suggestions would be helpful!

Similarly, when I set the material map, it comes into Revit at a unique scale.
To achieve a 0.30m x 0.30m size, I need to scale the image by 11.74.

If the scale were related to the actual dimensions of the input image, the first example scale would a factor of 1 (not ~40 because the actual dimensions of my JPG for the cutout textures are 1.8m Width x 0.45m Height).

When in the Feet units in Revit, bitmaps are not specified by feet, but by inches.

This one has 12" tiles.

I am not sure what the scale that bitmaps are specified in Revit, when in meters. I will need to test that.

Here is the bitmap I use to test size:

So the Metric template I am using is in mm. And the Bitmap Asset size is still in inches. So, to specify the correct size in mm I set a conversion factor on the Height and Width:

Hi @scottd, Thanks for looking into this.
I will have an in-depth look in a few days and reply here about how it works with my Meter units.

From this post that @kike was fielding, it appears that Revit works in inches in the background.

Seems that scalar inputs must be converted to Inches before sending through the Construct Bitmap Asset component.


Hi Kevin,

It looks like the Revit material API don’t follow same rules and can return you values in feets, inches or even other units.

We adressed this in the next release and all those values will be converted to the units you are using in Grasshopper.


There is new release available to download.

Here the Release Notes.

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Is this release also in the Rhino 7?
Or only in the Rhino WIP for the moment?

Not tested wih Rhino WIP but should work with both versions of Rhino.

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