Pixel Art Tutorial Series is currently the most popular thing on my page. The idea behind this is to take suggestions from the community and try to make a tutorial out of these things, helping out fellow deviants along the way. You can also find my pixel art tutorials in groups like #TutorialsForYou, #TutorialsClub and #PixelCommunity. Here is a list of tutorials in my Pixel Art Tutorial Series, tutorials which are underlined and bold are already ready tutorials that you can read, other tutorials without the underline are tutorials that will be posted in deviantART in near future. You can also suggest new pixel art tutorial series by commenting on my profile page, on these tutorials or by sending me a note. Enjoy!
Hehe, you are very welcome! As a newbie I was having so much trouble managing to make it and I couldn't find a single tutorial that explained it! Since your tutorials are so great I thought it made sense xP I'm glad it could also help more people!
you can use some simple math to make sure the measurements are right. For example, in steps one and two, the vertical lines are 29 pixels but the diagonal lines are eyeballed. Using the pythagorean theorum we find that the horizontal and vertical distance of the diagonal lines should be twice the square root of the vertical lines. So in this case, if the vertical lines are 29, the square root of 29 is 5.38... and twice that is 10.77... this proves that the 11 pixel distance you picked is the closest to a perfect circle you can do within the limited pixel range selected.
You can also use a variation on steps 1 through 4 to find the isometric circle directly. in a true isometric projection (very little pixel art claiming to be isometric is actually true isometric) the x, y, and z axis should be drawn a perfect 120 degrees from each other (hence the name isometric, meaning equal measure.) this means that any flat symmetrical object (like a round table top) will have a vertical distance 58% of its horizontal distance (the actual ratio is 1 to 1 over the square root of 3.) So if we take your diagram in the first part of the tutorial and "squish" it vertically to 58% we will get an isometric circle.
So: the horizontal distances stay the same. the vertical line squishes from 29 to 17, and the diagonal lines will squish vertically from 11 to 6 (remember, the diagonal lines are still 11 horiontally) this will give you an isometric guide from which to draw your circle.
Yeah, it's a good way to measure things and never go wrong with it. It's actually quite simple if you think about it as it's just a circle and it is easy to find values for a circle. However, I think that most people don't think about it like this as it might be too complicated. In this tutorial I calculated the first lines to be 29 pixels and 11 pixels but everything else I just draw as I thought would be good. But I do feel that it's good enough for general pixel art because it's important that it would look somewhat right to the eye. It doesn't have to be pixel perfect. But you have a good way to calculate circles.