1. When basing on the engineering technical drawing, isometric image presents objects without taking perspective into consideration. The objects are based on the diamond-shaped grate, as the picture below shows:
2. The traditional isometric image is based on the angle of 30 degrees, however due to the peculiarities of computer monitors, when presenting a picture on the monitor, angle of 30 degrees gives confused and rough line. They use angle of 25.565 degrees approximately at pixel graphics. Don't be afraid of mathematics appearance, there is no need in memorizing all those numbers.
3. In order to draw a line with the angle of 26.565 degrees, all you have to remember is one step upward and two steps lengthwise, this technology looks like an extended scale stairs. Look at the below picture. The lines were created in the following way: draw two pixels, then go one pixel up and draw the next two pixels at the end of the previous one.
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