1
$\begingroup$

The top view looks at the top of the objet from the top of the object, the front view looks at the front of the objet from the front of the object. All seems logical.

So why does the left-side view looks at the right of the object from the right of the object?

EDIT:

I'm talking about first angle projection. I'm not entirely sure but I think I doesn't change anyway with third angle projection.

For those who say it doesn't. It's in the words: yes, for the left-side view, the observer looks towards the left. But the side that he sees if he looks towards the left is the right-side of the object.

If we were following the same logic, front view would be the back-side of the object because the observer would be looking towards the front. But it isn't: for the front view, the observer looks towards the back.

The naming isn't consistent. Either we name the view after the direction we are looking towards, or after the side of the object that we see.

The position of the plane of projection doesn't change anything, it just changes were we draw it on the paper when we unfold the view.

Improve this question
$\endgroup$
11
  • 2
    $\begingroup$ Welcome to Engineering! I'd say it... doesn't? The left-side view... views from the left side, usually. Could you please edit your question with an image of the exercise you're looking at? $\endgroup$ – Wasabi♦ Nov 21 '19 at 0:24
  • 2
    $\begingroup$ I think you might be asking about views from either first or third angle projections. $\endgroup$ – Fred Nov 21 '19 at 4:03
  • $\begingroup$ I'm with @Wasabi - the left looks at the left. $\endgroup$ – Jonathan R Swift Nov 21 '19 at 6:49
  • $\begingroup$ I’m with Fred - either the view is progected past the ibject or brought between the viewpoint and the object... ie first or third angle. $\endgroup$ – Solar Mike Nov 21 '19 at 8:56
  • 1
    $\begingroup$ Ok, I've just added an image. $\endgroup$ – Jonas Daverio Nov 21 '19 at 13:22
3
$\begingroup$

This is a question of "my left or your left".

Imagine standing and facing somebody, as if looking in a mirror.

Now imagine the person in front of you saying "look left". Which way should you turn your head? it is their left, or your left? The choice you make affects what "left" means.

Unlike a human, an object does not have it's own point of view, therefore your left is always the correct answer.

Take a look at the image below. The views on the middle row here are (from left to right): Left, Front, Right, Back. (The remainders are Top and Bottom).

3D Views

Imagine that the box is a human being, standing, and facing towards you. The front of the human is their face, "their" left would be on the right hand side, as you look at their front.

3D views are named from the perspective of the viewer The Left view, is on the left of the object when you look at the front, from the outside of the object.

Likewise, the back view is on the back of the object, as you look at the front of the object, from outside the object.

The simple fact is, that physical objects are looked at from the outside in, not the inside out, and the views are named accordingly

Improve this answer
$\endgroup$
3
  • $\begingroup$ Oh, that indeed makes sense. But for front and back, what would it mean? What is your front and your back, for the object? But for all four other view, I now understand. $\endgroup$ – Jonas Daverio Nov 21 '19 at 14:08
  • $\begingroup$ You are standing looking at a person. Looking at their front. If you were to turn to your left, and walk around them, you would be able to see the left view. If you keep walking, you'll get to the back. It's all from the perspective of an external observer moving around the object. $\endgroup$ – Jonathan R Swift Nov 21 '19 at 19:01
  • $\begingroup$ I've edited my answer to include an explanation for the back view $\endgroup$ – Jonathan R Swift Nov 21 '19 at 19:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.