View Full Version : semi transparent object with opaque image map

10-08-2014, 10:05 PM
can someone clue me in on how to apply an opaque image map (w/alpha) to a semi-transparent object? i'd like the object to have transparency but the image map should be fully opaque.

thanks in advance for your help.

10-09-2014, 02:54 AM
Can you upload any type of example image of what you are trying to do? I'm finding it hard to visualize exactly what you are working on. From what you are saying, I gather you'd want like a sticker or label on a glass bottle or something?

10-09-2014, 04:30 AM
It's doable with one surface/object, but I usually just use two separate polygons and surfaces. Like adding a sticker to a window, I add a polygon in front of the window for the sticker and place the image and an alpha version on the transparency or a clip map.

10-09-2014, 07:05 AM
Here's an example. (http://forums.newtek.com/showthread.php?136307-Hans-Pieck-Lounge-Chair-modeling-and-renders&p=1330904&viewfull=1#post1330904)

It's as good as I could come up with, but there is a problem with the reverse side of the decal which appears dark and without color, perhaps someone could make it work so that the reverse side of the decal can also have a specific surface. I've also found adding geometry a more realistic solution, but sometimes the sticker might have a delicate intricate shape, or it might be paint splatter, the sort of thing you can't model easily.

10-09-2014, 03:16 PM
This thread (http://forums.newtek.com/showthread.php?140079-Urgent-help-need-with-weird-transparency-problem&highlight=juice+bottle) will probably help.

10-09-2014, 03:30 PM
Oops... working on it.

10-09-2014, 04:41 PM
I guess we should ask if you're in nodes or not. Same overall concept regardless. :hey:

Use a mixer node with an alpha input from the image map (the last part of the setup below).
As for DJ's secondary question.... Use the Polygon Side output of a Spot Info node to control the front and back sides of your "sticker" (double sided needs to be enabled. The front poly in this case).

Front 124875 Back 124876

Setup 124877

10-10-2014, 07:28 AM
thanks everyone for your responses. i was trying to accomplish it without nodes so it sounds like 2 models is the way to go. it is similar to a label on a bottle...it's an image sequence streaking down a glass tube.