In orthographic projection, projectors are lines that are perpendicular to the plane of projection (POP) and parallel to each other, used to represent an object's features onto the plane.
Understanding Orthographic Projection
Orthographic projection is a method of representing a three-dimensional object in two dimensions. It achieves this by projecting the object onto a plane using parallel lines that are perpendicular to that plane. These parallel, perpendicular lines are the projectors.
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Perpendicularity: The "ortho" in orthographic emphasizes that the projectors intersect the plane of projection at a 90-degree angle. This ensures that the resulting view accurately represents the object's dimensions along that direction.
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Parallelism: The projectors are parallel to each other. This ensures that there is no perspective distortion in the resulting view, meaning that parallel lines on the object remain parallel in the projection.
How Projectors Work
Imagine shining a light directly onto an object, where the light rays are perfectly parallel. The shadow cast on a wall behind the object is analogous to an orthographic projection. The light rays are the projectors, the object is the 3D form being represented, and the wall is the plane of projection.
Different Views
Orthographic projection is frequently used to create multiple views of an object (e.g., front, top, and side views). Each view is obtained by orienting the object differently relative to the plane of projection, but in all cases, the projectors remain perpendicular to the plane and parallel to one another.
Key Characteristics of Projectors in Orthographic Projection
- Parallel: All projectors are parallel to each other.
- Perpendicular: All projectors are perpendicular to the plane of projection.
- Dimensionally Accurate: Preserves the true size and shape of features projected onto the plane.
