3D Modeling 3D Modeling 5

Question 1

What is 'photogrammetry' in the context of 3D modeling?

Accepted Answer

A technique that uses photographs from multiple angles to reconstruct a 3D model

Answer

Photogrammetry uses overlapping photos of a real object or environment to compute a detailed 3D mesh and texture through software algorithms.

Question 2

Which type of 3D projection is commonly used in game engines because it preserves parallel lines and has no perspective distortion?

Accepted Answer

Orthographic projection

Answer

Orthographic projection displays objects at true scale regardless of depth, making it useful for isometric games and technical modeling views.

Question 3

In 3D modeling, what is a 'manifold mesh'?

Accepted Answer

A watertight mesh where every edge is shared by exactly two faces with no holes or non-manifold geometry

Answer

A manifold (watertight) mesh has no open edges, holes, or geometry errors, which is required for 3D printing and many simulation workflows.

Question 4

What does 'instancing' mean in a 3D scene?

Accepted Answer

Placing multiple references to a single mesh in the scene without duplicating its geometry data

Answer

Instancing references one mesh multiple times in memory, dramatically reducing RAM usage and improving performance for repeated objects like trees or rocks.

Question 5

What is 'UV seam placement' best practice when texturing a character's head?

Accepted Answer

Place seams along hairlines, ears, and the back of the head where they will be least visible

Answer

Seams placed in hidden or less-visible areas minimize visible texture distortion or seam lines in the final rendered result.

3D Modeling Practice Test

3D Modeling Practice Test

3D Modeling 3D Modeling 5