Sometimes it's good to return to the fundamentals. Or the real reason I'm posting test clipmarks.

Much of the creation of spaces in linear perspective relies on the establishment of a basic unit-the square. A square can be the basis for the construction of a grid, circular forms, and the establishment of inclines. This diagram illustrates a reliable method for approximating a view of a square drawn in linear perspective.

drawing grids in perspective
creating a circle using perspective
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