Creating Seamless Tiles and Textures
So, you've created the ultimate texture. With blood, sweat, and tears, the texture of your dreams has been born. You save the image to the preferred format of your game engine, fire it up, and when you see your texture in action, you begin to cry. Not because of the beauty of all your hard work coming to fruition; no, not at all. Rather, because you're frustrated because of the ugly seams in your texture.
Well, dry those tears and fret no more - I'm here to help you ensure that all your textures come out smooth and seamless from now on!
Making a tile or texture seamless - that is, without a visible "border" where the images meet - is quite simple. In fact, you can remove tile and texture seams with a few painless steps.
Here's a snow/ice tile I created. Looks fine by itself:
However, this view of a texture is never enough to tell whether it will tile. We must test it in our graphics app to see how horribly seamed it is. The easiest way to do this is to create a new image, twice the size of our original. Then we copy the image into the blank canvas four times, like so:
In one word: Eww. The seams are horribly obvious now. However, you should not fear - it is the seams themselves that should be quaking in their boots - we're going to wipe those seams right off the map!
To start, create another blank canvas, this time the same dimensions as your original tile/texture. Instead of pasting the image centered, though, paste it 50% off into the left side, and 50% off into the top side of the image. Then, paste the image three more times to fill in the canvas, like so:
Two tools are needed to remove the seams in a tile or texture - the dropper, and the airbrush. First, we should use the dropper to blot a color near the seams. We'll use this color to "erase" the smooth the seams over. Bust out your airbrush, and then start to blend the colors on the seams together. Be sure to use a soft, low-density, and small-sized brush.
Be sure to match the colors as best as you can. Don't be afraid to use different colors for different areas of the seams. As long as everything looks smooth, you're all right. When you're finished, your image should look like this:
One important note - be sure to only smooth areas in conjunction with the seams. If you change any other areas, you run the risk of making new seams! In general, avoid the areas near the corners of the image. I've highlighted the "bad" areas of the image for you. Avoid these areas at all costs:
Once everything looks evened out, try tiling your image to see the results. Make a new canvas, twice the size of your tile or texture, and paste four copies of the image into it. If everything went all right, we should now have a perfectly seamless texture:
Excellent! Our seams are completely gone now.
As you can see, it's not very hard to create a seamless texture or tile. It takes a little extra effort, but it's absolutely worth it.
As always, have fun!