Learning perspective is generally taken as a big deal. Here we are going to change that prejudice. How? First you have to get the basics, and fully understand how perspective works geometrically.

To be comfortable with perspective drawing you always have to keep in mind that there is a person watching a scene which consists of geometrical, or near to geometrical objects, with a specific angle. Now to get familiar with the language of perspective, let’s put it in a more technical way. Suppose you are taking a snapshot of a scene. What do we need? A camera (the eye – point of view), the object(s) (scene), and light (guide lines). And as a result we get a photograph (picture plane) in the end.

Perspective Basics

The most important parts in understanding perspective are the “point of view” (POV), rays of light that carry the vision to our eyes (guide lines), vanishing points, the ground level together with the axis of origin, and the picture plane.

Point of View: This is where we stand and look at the scene. This point is also where all the light rays gather, since these rays are received by the observer’s eye.

Axis of Origin: Remember maths class when we drew x,y graphs. We had an axis of origin, where x and y both had values of zero. It’s primarily the same thing. We construct our perspective on these axi just like the graphics in math. Actually it’s 3 dimensional and we place the center on the picture plane, so that the picture plane and ground are sliced in two. A third axis can be imagined parallel to the bottom line of the picture plane.

Perspective view

Picture Plane: This is a totally imaginary plane representing our drawing canvas. We use it to project our guide lines that come from the scene, as if we are taking a photograph. The picture plane actually catches a vision of the scene

Guide Lines: These lines represent light rays carrying information of colour and geometry to our eyes. We use these lines by intersecting with the picture plane. This way we get the projection of objects from the scene onto our canvas. They are also called ghost lines. We don’t see these lines in the final picture.

Eye Level: Imagine you’re xray man. Rays come out of your eyes, focused on your scene. The level of the rays would give you your eye level. If you look up or down, the rays coming out of your eyes would have an angle. In 1 and 2 point perspective the vanishing points are on this line.

Perspective from top view

Horizon Line: It’s the contour of the landscape at the depth of your scene. Although it is different than eye level it can be taken the same if we are looking straight ahead, parallel to the ground level. The horizon line is generally a little below the eye level.

Ground Level: This is the level our picture plane touches the ground. For this we have to assume the ground is horizontal, and even. If we have uneven ground, we either imagine a straight level, lets say that intersects the corner of an object on the picture plane, or, if there are steps we accept one of these levels as ground level.

Scene: The composition of objects that we intend to represent in our perspective drawing, which could be of organic or man made objects, it doesn’t matter. Keep in mind that we are going to abstractify the scene into geometrical shapes in order to easily depict on our canvas.

Perspective from side view

Vanishing Points: I was just about to forget these. Oops! Shame on me! These are the points that our geometry in the scene tend to be drawn towards. The truth is every set of parallel lines vanish towards a differnt vanising point. Because we generally have orthographic (box shaped geometry) scenes we get up to 2 vanishing points horizontally. If we had a geometry of well, let’s say a more complex scene of 4 sets of parallel lines, we would have had 4 vanishing points. Generally we abstractify the lines that don’t fit in our normal orthographic set of lines to our existing vanishing points, instead of complicating the scene with more vanishing points.

Now we know the main terms, before we start, a thing to always remember when dealing with perspective is to visualize the scene before depicting on paper.
Imagine in your mind’s eye what the scene would look like before you pick up your pencil. It will make things a lot easier. When imagining, don’t forget to think as if you were taking a snapshop of the scene, as I mentioned before.
When imagining the scene we have to visualize it from more than one viewpoint to be more accurate. I mentioned before that we project guidelines onto the picture plane.
We can see our scene from top and side views to visualize the projection of the guideline coming from each object. I will not go into detail here. What I have already explained is enough for this post. For now I can say that the point where the guideline intersects the picture plane gives us the location on our canvas, of the specific corner the guideline comes from.

We need to visualize the scene, I repeat, to make the scene conceivable. This is why we abstract what we see into geometrical objects, points and lines. Don’t forget that all these lines and points are imaginary, we do not really see the guide lines, horizon line, ground line, etc… . We need them to construct the perspective. These lines and points help us imagine and convey onto paper. If you are successful in visualising and drawing what you see, you might not even need to use these points and lines when depicting your scene on paper. However, it is always beneficial to know the basics of perspective, if you intend to draw.

On my next post on perspective I will be explaining “1 point perspective technique“. We will get more familiar with how to use the basics I have explained in this post.