One-point perspective: principles.

🎯 One-Point Perspective: Principles

One-point perspective is a method of graphical projection that creates the illusion of depth by making parallel lines converge toward a single vanishing point on the horizon line. It mimics how the human eye perceives objects that are directly in front of us.

1️⃣ Key Principles

  1. Horizon Line (HL)
    • Represents the viewer’s eye level.
    • All vanishing points lie on this line.
  2. Vanishing Point (VP)
    • A single point on the horizon line where all parallel lines (receding in depth) appear to converge.
    • In one-point perspective, only one vanishing point is used.
  3. Parallel vs. Perpendicular Lines
    • Lines parallel to the picture plane (front faces) are drawn in their true shape and size.
    • Lines perpendicular to the picture plane recede toward the one vanishing point.
  4. Foreshortening
    • Objects appear smaller as they recede into the distance.
    • Equal distances in reality look progressively shorter in the drawing.
  5. Station Point (SP)
    • The eye position of the observer.
    • Determines how close or far objects appear.

2️⃣ Steps to Construct a One-Point Perspective

  1. Draw a horizon line at eye level.
  2. Mark a single vanishing point (VP) on the horizon line.
  3. Draw the front face of the object (true shape).
  4. From each corner of the object, draw lines receding to the vanishing point.
  5. Add the back edges by cutting off receding lines at desired depth.
  6. Darken the visible outlines → realistic perspective view.

3️⃣ Examples

  • Corridor or Railway Tracks → parallel sides converge at one point on the horizon.
  • Buildings Viewed Front-On → front façade true shape; sides recede to vanishing point.
  • Roads, Tunnels, Bridges → straight paths narrow into the distance.

4️⃣ Applications

  • Architectural drawings (interiors, streetscapes).
  • Urban design visualizations.
  • Fine arts and photography (framing depth).
  • Teaching perspective basics.

✅ In summary:
One-point perspective is based on the principle that all receding lines converge at a single vanishing point on the horizon line, making it the simplest and most widely used perspective technique for depicting depth and distance.