How to create a decal correctly..

[Bikerdude]

Evening

 

This is beginning to annoy me, I cant seem to understand how to create a decal with an transparent alpha channel correctly.

 

I quite like using Gimp, so could someone point me to a simple guide or howto so I can learn howto do this the RIGHT way...

 

ta.

[jaxa]

I can help you with this. Maybe PM me the file?

[jaxa]

I'm not exactly sure what you want to do so I'll just lay out these steps.

 

1. You have an image with a color or regions you want to make transparent.

2. Use the fuzzy select tool or whatever selection tool you need to select what you want to be transparent. You can hold shift and click to combine a new selection with the existing selection.

3. Layer -> Transparency -> Add Alpha Channel

4. You could press delete right now and you would have transparency, but with a jagged edge along the non-transparent parts.

5. Instead, go to Select -> Grow. 2 pixels should be fine. That expands the selection along the edges.

6. Then go to Select -> Feather. That applies a transparent fadeout to the edge. Again, 2 pixels should be fine.

7. Press delete. Look at the results. Try copying and pasting the decal onto a new image with a different background color to look for defects. You'll want to use Edit -> Paste Into.

8. If there are any defects you should be able to select them individually, feather them, delete, as needed.

 

Edited June 22, 2013 by jaxa

[Springheel]

Depends what kind of decal you want to make as well; dirt decals are easier to make.

[jaxa]

You could also just start out with a transparent image and draw on a decal I guess.

[Bikerdude]

1. You have an image with a color or regions you want to make transparent.

2. Use the fuzzy select tool or whatever selection tool you need to select what you want to be transparent. You can hold shift and click to combine a new selection with the existing selection.

3. Layer -> Transparency -> Add Alpha Channel

4. You could press delete right now and you would have transparency, but with a jagged edge along the non-transparent parts.

5. Instead, go to Select -> Grow. 2 pixels should be fine. That expands the selection along the edges.

6. Then go to Select -> Feather. That applies a transparent fadeout to the edge. Again, 2 pixels should be fine.

7. Press delete. Look at the results. Try copying and pasting the decal onto a new image with a different background color to look for defects. You'll want to use Edit -> Paste Into.

8. If there are any defects you should be able to select them individually, feather them, delete, as needed.

Sweet I will try this.

Depends what kind of decal you want to make as well; dirt decals are easier to make.

I'm trying to make 2 snowflake decals for TDM 2.0

[Springheel]

Snowflake decals could probably be done with an additive blend, rather than transparency. You make an image where everything you want transparent is pure black, and the snowflakes are varying shades of white/grey. The more pure white they are, the more opaque. Grey is partially transparent.

[Bikerdude]

well I found two free images via an image search and did jaxa's steps on it. I found the issus that was causing them to appear with the black square around them was I had been using the wrong compression (DXT1) instead of DXT3/5.

[Mr Lemony Fresh]

Also I'll just leave this very cool tutorial here which helps in getting the best transparent texture. Recommended from the polycount forums.

 

http://www.cgtextures.com/content.php?action=tutorial&name=alphabg

 

That tutorial tells you about a trick where you duplicate the images, put it behind the other and blur it and copy it till it spills colour from the general areas around the transparent image. Then you mask it. And that way when you're in game you don't get white/black/weird edges due to anti-aliasing.

[Bikerdude]

ta.

[Mr Lemony Fresh]

Also sometimes no matter how well you get rid of the fringe, the png format will take out chunks of the solid channels of your image to save room where the opacity is 0. To fix this, make the whole image have at least 1% opacity.

[Artsupplies]

Be sure that your blank ware is slightly whetted so that the decal may be moved easily and positioned correctly.

 

Paint Color Palettes | Oil Paint | Acrylic Paint

[Bikerdude]

Spammer..?

[Mr Lemony Fresh]

Lol def! who you gonna call?