A very simple practice for myself to render a half-circle using the pen function of Scratch. The point of the program though is to indicate which time of day it is and which ones are behind and upcoming.. however it only works for my local latitude(Vilnius, Lithuania) and different time zones will probably have an effect as well...
TURBO MODE REQUIRED! As for computer graphics, computer software is typically WAY faster than this flash thing Scratch runs on. The way I render is the circle is simple. (Math terms I kind of tried to translate are incoming... I speak Russian since birth and study in Russian/Lithuanian, so I am not sure I'll name mathy stuff correctly) I put a drawing sprite at the center of the circumference(x=0,y=-120) and calculate its x and y using derivative formulas from the circumference function(x^2+y^2=R^2, only works for circles whose center is at the center of the xy plane), it is pretty much very similar to the pythagorean theorem, if you treated the destination points as one point of a right triangle and then cathetuses/legs of the right triangles would make up for x and y offsets. So I repeat this process for all of the 180 degrees starting from that center. The only problem is that it takes a long time to draw. Each single step only increases the degrees by 0.01. This is because if I drew just all of the lines for 180 attempts using the function, there would be a lot of empty space on the edges, because of how quadratic stuff works. The more precision there is in angles, the less of that empty space there is. I eventually found the sweet spot to be 0.01.
