How do I stop the shadow from a transparent png?

I’m very new to the 3D world. I’ve applied a transparent png logo to a model I made and the box of the logo casts a shadow on the model no matter how close i put it. Is there a fix for this? I’ve tried turning off shadows in entity info.

Please attach the logo’s PNG so we can see what you have.
ALL of the pixels you want to be ‘transparent’ need to have 100% transparency…

this is v-ray problem is not related with sketchup it self.
In order to have trasparent background you need to add in the alpha channel a b/w image where the black is the cut part inside the material editor of V-ray.

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Did you explode the PNG after you imported it? See comparison with the png exploded, then grouped on the left and not-exploded on the right.


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In this case, a png as image directly on another background face, changing its property (don’t cast shadow) would have been enough. As @TIG, says, the pixels surrounding the logo should be 100% transparent.

Thank you very much! this worked. (sorry it took a while to reply, My account got put on hold for posting too fast.)

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Sorry, I actually uploaded this image yesterday but I think it was blocked.

Great and no problem. Thanks for letting us know!

The surrounding pixels are transparent !
So can I suggest you place the image in empty space, then explode the image, then edit the rectangular face to delete the outer parts.
Then save it as a component, and place an instance where you want…
Here’s an example…
CryoSafe.skp (40.3 KB)

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Thanks so much for this. I tried doing this myself by tracing the transparent areas with the line tool - then deleting. Is this not the correct way to go about this? I’m left with black lines around the logo’s border that delete the logo when I attempt to remove them.CryoSafe_logo.skp (290.1 KB)

Select just the edges and then hide them.

CryoSafe_logo.skp (333.2 KB)

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Thanks!

You’re welcome.

In the attached file in my previous post, I created a component of the label with the hidden edges. If you want to apply that to a surface, position it on the face and then explode it. the edges of the label will divide the larger face into two regions. The inner one will have the label image as the material and the outer one can be painted whatever color it needs to be.

Here I have the hidden edges displayed so you can see them.

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Thanks again.

Do you know of a good way to place the logo on a cylinder? I’ve tried the tutorials using materials and paint bucket but the logo image is applied to each side of the cylinder making a big mess of things.t

I was just in the process of making something up to show that. Hang tight.

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The angles on the sides create a problem for bending the image. Here’s a method using only native tools that will get it done, though. First, get rid of the transparent pixels. You could use your original image without the transparent pixels. Since I didn’t have that, though, I drew a rectangle slightly larger than the label so that I had the inner and outer regions as I describe above. I painted the region outside the label to the tank color. I just picked a color here but I expect it should be white or something.


I selected both the inner and outer regions, right clicked on them and chose Combine Textures. This creates a new textured. Then I made sure it was set to Projected.

On the cylinder, which I centered behind the label image, I copied the edge down twice to define the height of the label. With Hidden Geometry turned on, I could then paint the individual faces with the texture by sampling from the label.

Then you can paint the rest of the tank.

FWIW, you could also make the label the full height of the side of the tank.

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Hi Dave,
I’m having some trouble with the render. Any thoughts? I could have easily did something wrong lol.

Can you upload the SKP file?

LD30.skp (3.4 MB) Here you go

I expect part of the problem is that you have the faces reversed on the canister. It may also hae something to do with the rendering application. I fixed the faces, reapplied the materials, added a platform and set up a render in Kerkythea. The label looks good there.

For this render I didn’t bother to give the canister material any special properties.

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