Originally Posted by
TheHoarseWhisperer
2. this is a bit more specific. What's the PS filter you use? Is it Render Clouds? I sometimes use render clouds, and it's good because it looks natural and it is random, which is fun. So, I'm going to assume you have a randomly generated set of landmasses/continents. Here's something to try:
- look for places on your map which might mark tectonic boundaries. For example, if you have a long narrow sea (such as the Red Sea or the Mediterranean) that might mean the continents are tearing away from each
other, so put a divergent boundary through there.
- look for areas of coastline that are not too jagged (don't have too many inlets, peninsulas, bays, etc.). The west coast of South America is a bit like this. That is where a mountain range has been thrown up over a
convergent boundary, so put one of those along that area.
- look at the oceans. Are they large and roundish (like the Pacific) or long and rectangular (like the Atlantic). If the former, they might be sitting on their own plate, so you draw a line that goes around the ocean, not
necessarily keeping close to the edges (again, keep an eye on an Earth map); if the latter, they might be the result of a rift that got too big, in which case put a divergent boundary running most of the way down the
middle.
- if you have islands in the middle of nowhere, they might be sitting on either a convergent or divergent boundary. Islands which are long-ish (eg. Papua New Guinea, Japan, Cuba) are on convergent boundaries (if you
have one side which has a jagged coastline and the other side of the island is smooth, you know which side to put the tectonic boundary (see above); islands which are round (like Iceland) are rarer and often sit on
top of divergent boundaries (the same place as the mid-oceanic ridge from the previous point). Add the lines as necessary.
If you do those things, hopefully you will now have a handful of tectonic boundaries placed. Now start joining them together, and adding more as necessary. Remember, tectonic plates will usually not cut straight through a continent.
If you're still having difficulty, you can just draw a line around each of your continents so that they all sit on their own plates, and then divide up the ocean afterwards. This won't give you a perfect tectonic map, but it might help you get started. After that, you can edit as much as you want until you think it looks right.
And lastly - I can't stress this enough - remember that planets are round. If you have a border going off the east of the map, make sure to continue it on the western side; if you have one going into the north or south, that is slightly more complicated, but I explained all that in the previous post.
Does that help? Let me know if it doesn't, or if you're still having problems.