1. ::One Point Perspective::
One point perspective is one of the easiest
perspective drawing styles available.
The reason for this is that all lines lead to a single
point, and regardless of how complex your object is,
it's easy to realize when you've made a mistake, and
just as easy to correct it.

2. What is One Point Perspective?
Dictionary.com define one point perspective as:
...a mathematical system for representing three-dimensional
objects and space on a two-dimensional surface by means of
intersecting lines that are drawn vertically and horizontally and that
radiate from one point on a horizon line...
Although this definition sounds complicated, the concept is relatively simple. One point perspective is a drawing method that shows how things appear to get smaller as they get further away, converging towards a single ‘vanishing point’ on the horizon line. It is a way of drawing objects upon a flat piece of paper (or other drawing surface) so that they look three-dimensional and realistic

3. Key Terms to Know
The horizon line is the eye level of the viewer.  This line
sets up the orientation of the scene and gives the viewer
some bearing as to how the visually relate to the image. 

4. Key Terms to Know The vanishing point is on the horizon line where
perceptually all things converge.  In one point perspective, the objects appear to diminish they follow a path back from the
front of the scene to a single point.    

5. Key Terms to Know
The orthogonal lines, are the lines that move from the
object to the vanishing point.  The purpose of these lines is to set up the visual path to the vanishing point, directing the
shape of the object in perspective. 

6. Two Important Rules: Before we jump in, there are some important
rules to keep in mind when drawing in one
point perspective.
All vertical construction lines are parallel to
one another;
All horizontal construction lines are parallel to

7. Choosing Your Vanishing Point
Keep in mind that the position of your vanishing point is critical. The further away you move from the center of the canvas, the more biased your
perspective will be to one side of the object.
Basically, your image is affected similarly to how your object's position, in relation to the horizon
line, affects if you see the bottom or top side.
If you go very far to your left side, and your
object is located on the same side, you risk only being able to view two sides of your object
instead of three.

8. Less Than Ideal Placement of the Vanishing Point
As you can see, choosing a vanishing point on the same side as
your object limits the sides you're able to render.
Imagine if you'd have decided to also lift the box by a few centimeters! That would basically leave you seeing a single face and no possible hint towards the volume of your object. 

9. Good Placement of the Vanishing Point
In contrast, the image above displays a more appropriate vanishing point placement.

10. Can you find the vanishing point, orthogonal lines, and eye level in this artwork?
'Bedroom in Arles' by Vincent van Gogh

11. TA＼( ˚ ▽ ˚ ) /DA
'Bedroom in Arles' by Vincent van Gogh