In Graphics, which of the following statements is/are true? Back-face
2018
In 3𝐷 Graphics, which of the following statements is/are true?
P: Back-face culling is an example of image-precision visible-surface determination procedure.
Q: Z- buffer is a 16-bit, 32-bit, or 64 bit field associated with each pixel in a frame buffer that can be used to determine the visible surfaces at each pixel
Choose the correct answer from the code given below :
\(𝐶𝑜𝑑𝑒:\)
- A.
P only
- B.
Q only
- C.
P and Q
- D.
Neither P nor Q
Attempted by 76 students.
Show answer & explanation
Correct answer: B
Answer: Only the statement about the Z-buffer is true.
Reasoning:
Back-face culling is an object-space (polygon-level) visibility test. It checks polygon orientation or face normals relative to the view direction and discards faces that face away from the camera before rasterization. Because it operates at the polygon/object level rather than per pixel, the back-face culling statement is false.
A Z-buffer is a depth buffer stored per pixel in the frame buffer and is used during rasterization to determine which surface is visible at each pixel. Common precisions include 16, 24, or 32 bits; higher precision variants such as 64-bit can be used in special cases. Therefore the Z-buffer statement is true.
Conclusion: Only the description of the Z-buffer is correct; the back-face culling description is incorrect.