Читать книгу SketchUp For Dummies - Mark Harrison - Страница 40

For computer programmers, drawing 3D objects on your screen is a difficult problem. You wouldn’t think it’d be such a big deal; after all, people have been drawing in perspective for a very long time. If Fillipo Brunelleschi could figure it out 500 years ago, why should your computer have problems?

The thing is, human perception of depth on paper is a trick of the eye. It isn’t really an optical illusion; it just looks like one. And of course, your computer doesn’t have eyes that enable it to interpret depth without thinking about it. You need to give your computer explicit instructions. In SketchUp, this means using drawing axes and inferences, as we explain in the sections that follow.