Image Mask Problem

I was trying to create a set of bushes using an image mask but I am not even coming close. Here is a screen shot of what is showing in SketchUp and the Skatter composition editor. Hope someone can tell me what I am doing wrong. I really wanted to use the mask in a render with some other stuff but can not seem to figure out how to accomplish it. I am also attaching the image I generated to use as the mask.

This is SU & Skatter info

Here is the image I was using (at least attempting to use) as the mask.
SU Logo

Does the host surface have texture coordinates? ie does it have a material applied to it that can be used to scale the image on the surface?

Otherwise Skatter can generate texture coordinates. More info here:

Thanks I will try agin. Now for another silly question, how do I refine this to a certain/small area of mo model?

You can combine an image mask with other types of masks (Area mask, Paint mask, etc).

OK - how do you combine them.

I somehow lost the model that I got to work originally and for some silly reason cannot get it to work again. When you say that i need a texture, what exactly are you saying. If I apply a SketchUp material, does that qualify as a texture or do I need something else? In this case, I applied a grass material to the composition surface. I seem to be going backwards. :disappointed:

OK, here is my latest test…

What am I doing wrong?

I really want to understand the process of using an image mask! Does the image need to be transparent? I also want to understand how to make something like this just part of a model instead of the whole thing (i.e. how do I combine masks).

Here is an image I generated once before but lost the sketchup file and cannot reproduce. It shows what I am trying to accompolish.

Here is my SketchUp file for this project/model:
SU Image Test.skp (787.6 KB)

Yes. In that case, the surface now has texture coordinates which Skatter can use. This is the “Input Front” mode.
You can change the texture position and size, which will affect the position of the image mask. Note that if you change the texture position while the Composition Editor is open, you’ll need to “refresh” by selecting another mode and select “Input Front” again.
See the attached gif.

You can also override the texture coordinates by having Skatter generate new ones with other modes like “Plane XY”.


Thanks, I am now headed in the right direction. However, how do I combine this with another mask or restrict this to just a section of my model/scene?

Here is an updated version.

I also used a Twilight Render infinite plane. I used the same texture and tried to adjust it to match the texture in the image mask so it would blend but it did not match well. Now I have to learn how to combine some things. Here is the scene/model I would like to combine the SketchUp logo image mask with (I want the SU logo to appear in the lower right corner).

You can add as many mask as you want.
Here is an example combining an image mask with an area mask.


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OK I can do that but what I want to do is limit the size of the image mask by only allow it to be done within the size of the area mask. How do I do that?

OK, here is my latest effort. While I think I did make some good progress, here are some issues I think I still need to understand better:

  • How do you create an area mask…(once I understand how to do that correctly I then want to combine it with an image mask, and I want the image mask to use the area mask as its boundaries)

  • Is there a way to project the image mask (and or an area mask) along the terrain of a model…(I wanted my SketchUp logo to follow the terrain in the model instead of having to create it on a flat surface)

Well, I did some more reading and experimenting and found that my previous questions were pretty done. In the model below, you will see that I figured out how to place the SU logo on the terrain without having to place it on a flat surface. Here is the result:

In order to accomplish this I went off and created a set of lines in the shape of the SU logo. I had to create to groups in order to get it to work. In Skatter, I then used the 2 sets of lines as curve masks and set the width for each of the masks to 1. That way I did not get any drifting away from the lines. Well, at least for me this worked. I could not figure out any way to use the image mask to achieve this result. If someone know how, I sure would like to know. :smiley:

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Please check out this page of the documentation: Masks - Skatter Help

Area masks are projected onto surfaces (you can draw them above the terrain and instances below the mask will be masked).

Image mask are different : they apply directly on a surface since they use its texture coordinates.

Also, to make it easier to understand how the image mask texture is positionned, you can enable the “Display the texture” option (see Masks - Skatter Help, only available in SketchUp 2020 and later versions).

Yes, I did go back and read all of the documentation (actually did it before my last post). As you see in my last post I did figure out a way to use the SU logo for two different instances. IMO, I do not see a lot of use for the area mask since it is circular in shape and the image mask is a little restrictive since you can only use it on a flat predefined surface. Again, IMO that is a little restrictive.

In a future release I would like to see the ability to control the shape of a mask so that not all masks are round. I would like to be able to have square edges.

All of this aside, I was happy that I finally figured out a way to draw the logo on a sloped surface. I do not want my comments to be taken in a negative view. I guess I just got frustrated until I figured ou a way to do what I wanted. :grinning:

Area masks can take any shape, not just circles :wink:
Just draw closed polygons and it should work.

You can also use ThruPaint to position textures on non-flat surfaces.

Area masks can take any shape, not just circles :wink:
Just draw closed polygons and it should work.

How do you do that? Can you post an example. :slightly_smiling_face:

You can also use ThruPaint to position textures on non-flat surfaces.

But does that allow you to use the image mask on that surface? Guess I am a little confused about what you are saying. What does this accomplish?

OK guys, I figured out 3 different methods (masks) for generating the SU logo in a terrain.

  • Top left is a line/path mask

  • Top right is an area mask

  • Bottom right is an image mask.

I appreciate the feedback. Still not sure what ThruPaint would accomplish other than maybe setting the texture for an image mask.
:grinning: :+1:

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Well you can just draw any shape, using SketchUp’s tools and then select the shape as the area mask :slight_smile:

Yes, that is what I figured out/did in the previous post (top left SU logo).

Thanks for the reply. :+1:

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