# Orthogonal Projection – Orthographic Representations – Step by Step 2

Orthogonal projection – Orthographic representations (page to continue: Projeções Ortogonais – Representações Ortográficas – passo a passo 1)

## Continued Walkthrough of Educational Animation: Orthogonal Projections – Orthographic Representations

### Page 2

#### Continued from: Orthogonal Projections – Orthographic Representations. – Step-by-step 1

### First diedro

The perspective object is positioned in the first dihedral, parallel to the three projection planes and the same distance from them (orthographic projection). The observer is also positioned in the first dihedral, looking directly at the p.v.s. (Vertical Plane Superior).

Approach the camera and conceal the dihedral II, III and IV for clarity

## Conic Projection

We add a spotlight in the first quadrant so that their projectors are directed to the Vertical Plane Superior. Note that projectors delimited what we call, in this work, ‘the shadow of the object’. Also note that this ‘shadow’ is quite distorted. See the light point is the summit and the projectors the generatrices of a cone, this is the conical projection.

Answer this question: What would happen if we moved the object away from this spotlight?

### Front Cylindrical Projection – Representation Spell

Answer: the ‘shadow’ would become less and less distorted, more and more congruent to the object. In fact, when the focus of light reached infinity (the so-called ‘improper spot’), the projector’s rays would travel parallel to each other and the ‘shadow’ would be the projection of the geometry of the object without distortion. The orthogonal cylindrical projection – Orthographic representation – of the object in the Upper Upright Superior projection plane is called the ‘Frontal Projection’.

Tip: It is good practice to position the object so that the frontal projection is the one that best characterizes your geometry.

### Top Projection – Representation Spell

We have added a new focus to the first quadrant, so that its projecting is directed to the Horizontal Previous Plan. When the focus of light is on the infinity (infinity) and projectors pass to be cylindrical and orthogonal, we have the so-called projection or top view. ‘ Know that this projection has been called ‘plant’.

### Profile Projection – Representation Spell

To be continued: Orthogonal Projections – Orthographic Representations – Step by step 3