UNIT 11

Question 1

The frame buffer is the area of memory where the screen is stored, while the back buffer is a backup buffer in case the frame buffer becomes corrupted.

Answer 1

False, frame buffer is the visible frame where the computer visibly draws to. Back buffer is where the hidden frame is rendered before being sent to the frame buffer.

Question 2

The back buffer is either copied to the frame buffer, or the buffers are switched. Switching buffers includes double copying; therefore, copying the back buffer to the frame buffer is faster.

Answer 2

False, the switch is done by telling the television or monitor to read data from the other buffer, rather than copying memory

Question 3

To increase rendering speed, a programmer can decide to only render visible objects. This is only problematic if some objects are partially visible.

Answer 3

True

Question 4

Rendering objects in a specific sequence, from far away to nearby, for the sake of showing only visible objects, is not an optimal method.

Answer 4

True

Question 5

The depth buffer solves the problems of visibility, except for the example of the ‘bird in the cage’.

Answer 5

False, it solves this problem because for each pixel on the back buffer, there is a corresponding pixel in the depth buffer which is never directly displayed on-screen. It just decides which pixels are visible and which are not.

Question 6

Stencil buffers are anything that requires pixels to be rejected on a pixel basis.

Answer 6

True

Question 7

Triangles are the most commonly rendered shape because they are the simplest primitives that can describe a surface in space.

Answer 7

True