Drawings have a one-point perspective when a single vanishing point (VP) seats on the horizon line. The position of the vanishing point can vary in its horizontal location, but it always stays on the horizon line. Therefore, draw the horizon line first, then determine the VP position on it.
In the image below you see how the road lines converge in a single VP. The right position of converging lines helps you draw with accuracy the exact size of objects receding in space. For instance, the trees’ size on the right changes in accordance with the linear perspective.
We observe such perspective by looking at highway roads, railway tracks, hotel hallways, or even buildings that we see facing us directly. The image of a hallway above shows the position of one VP on a horizon line, and all lines converge in it far in the distance. This helps us draw the exact size and the slant of the hotel’s doors and lights.
Images have a two-point perspective when they have two vanishing points (VPs) present on the horizon line. Seen from the corner, one wall of a barn or a building would recede towards one vanishing point on the left, while the other wall recedes towards the opposite vanishing point on the right, like shown here.
In the picture, two vanishing points are often placed at varied, uneven distances on the horizon line. This explains a different slant of one side of the building in comparison to the other. The closer the VP, the sharper the roof’s and wall’s slant. (In this picture, the right side of the barn has a steeper slant, with converging lines going to a much closer vanishing point in comparison to the left side).
Because of the linear perspective, objects often appear foreshortened, and if you don’t draw them as such, you lose your sense of perspective. Here, horses in the distance become smaller and foreshortened.
Assignment 1: On a new page in your sketchbook draw a simple example of one point and two point perspective.
Assignment 2: On a large sheet of paper provided create a house and outbuilding/garage using two pt perspective.
The main building: 4+ windows along two walls, 1+ door, porch roof, house roof, fenced in front porch with railings along side of two steps down, sidewalk in to house and to garage/out building.
Outbuilding/garage: door opening, roof, driveway in
Simple landscape (trees, hedges, gardens, fences), sky (clouds – no visible sun. Sun will be implied through shading) and driveways/walkways.
Demonstration in class.
http://www.craftsy.com/blog/2015/11/perspective-in-art/
