decals on glass ?

[JezUK]

Quick question.

I often need to put decals onto glass, usually it's a piece of frosting.

Whenever I've tried to make such a material, I've ended up having to make my bitmap and mask as big as the sheet of glass itself. If I keep the mask and bitmap just as big as the decal itself I can never remove the mask completely, it is always visible......

I use a VRayBlendMaterial.

Can anyone suggest where I'm going wrong because for sure, there has to be a way of putting things like stickers onto glass with just the sticker bitmap being only the size of the sticker (and not the entire size of a sheet of glass).

Many thanks.

[Alex_M]

Can you explain what you mean by "remove the mask completely" and why you need to do this?

Here's what I do to put decals with VrayBlendMtl. I've also attached a sample scene below.

1. In the coat slots put your decal materials and in the blend amount slots put your masks. Remember to set the swatches by the blend slots to black otherwise the coat material will show beyond your mask boundaries.
2. Go in the blend amount slots and remove both checkmarks that say "tile" if you don't want your decals to tile in any direction.
3. Assign a unique map channel ID for each of your decal mask if you want to control their UV placement with UVW Map modifier.

I hope this helps!

[JezUK]

Can you explain what you mean by "remove the mask completely" and why you need to do this?

Here's what I do to put decals with VrayBlendMtl. I've also attached a sample scene below.

1. In the coat slots put your decal materials and in the blend amount slots put your masks. Remember to set the swatches by the blend slots to black otherwise the coat material will show beyond your mask boundaries.
2. Go in the blend amount slots and remove both checkmarks that say "tile" if you don't want your decals to tile in any direction.
3. Assign a unique map channel ID for each of your decal mask if you want to control their UV placement with UVW Map modifier.

I hope this helps!

Thanks Alex - but your example is for a material that isn't a piece of glass, and that is my particular problem - I'm talking about glass.

Please could you try solving this - create a sheet of glass, 3000mm high, 2500mm wide, and 10mm thick.

Now for that sheet of glass, I'd like 2 bands of frosted glass - 300mm wide and 500mm apart with the bottom band of frosting being 1200mm off the ground.

Please create a material for that, for the two frosted bands. I've found that when I've done this, unless I make a bitmap that is 3000mm high, then I'll see where the mask is happening.

Make sense ?

Thanks for your help.

[White Wizard]

I've done this recently. Needed a decal of a logo on frosted glass which then gets fractured by a bullet.

Create a vrayblendmtl and put your glass as the base material. Create a vraymtl in the first slot (for your deca)l. Make a composite material in the decals mask slot. Put your alpha bitmap in the composite slot if needed and put an rgb tint map under it set to full black. Make sure you have a uvw modifier set to a separate channel for the object and the decal/mask bitmaps. You can move the uvw around in the viewport to position the decal although I don't believe it shows up until render time. Make sure for the decal you uncheck tile and mirror in bitmap settings otherwise the decal will repeat.

EDIT: Nvm. It seems you might be asking for something different.

[JezUK]

Hi Alex and thanks White Wizard,

Alex, I found that when I tried to make your plane into a 10mm thick sheet (Edit Poly, extrude faces), I'd get strange results (that simply didn't work) - so I deleted that and created my own plane and applied an Edit Poly Modifier, did a 10mm extrude, applied copies of your material to my 'glass pane' and it worked.

I'm not sure why I was getting issues with masked areas showing, I'm well aware of unchecking tiling, etc etc, so can't really explain it - but it all seems to be working as expected.

Many thanks.

[Garryclarke]

Hi Jez

I think I know the issue you're having, took me a while to figure out when I made the transition to Vray.

In the blend material there is a colour chip between the 'Coat Material' and the 'Blend Amount', by default this is grey. If your mask graphic is, say, white text on a black background then you need to set this chip to black.

Hope this helps

[fiddypea]

Thanks Garry Clarke! This has been bugging me for years!

[JezUK]

Hi Jez

I think I know the issue you're having, took me a while to figure out when I made the transition to Vray.

In the blend material there is a colour chip between the 'Coat Material' and the 'Blend Amount', by default this is grey. If your mask graphic is, say, white text on a black background then you need to set this chip to black.

Hope this helps

Sorry Garry, I forgot to thank you also - many thanks. It's little tidbits like that which help fill the gaps in our knowledge

[Raph4]

Can anyone suggest where I'm going wrong because for sure, there has to be a way of putting things like stickers onto glass with just the sticker bitmap being only the size of the sticker (and not the entire size of a sheet of glass).

Finally, your question is solved ?
If need, here is screenshot how I use sticker on Mat.



sticker settings
(here I use default scale (1) instead of realistic sticker scale size because it's easier for this object for me, but you can use his real size if you prefer)



sticker color
If your sticker is textured, use your image file with Diffuse Map on your sticker Mat.(here Material #14)



sticker size



sticker repeat


I hope this helps you and others also.



Edit: I add one scene "decal on glass" (if need)

[AC5L4T3R]

Is this what you're after?

https://www.youtube.com/watch?v=O_FZs1jaRzI

It's in Spanish but the auto-translated closed captions don't do a bad job.