Difficulty: Medium
Correct Answer: flicker and slow update
Explanation:
Introduction / Context:Display technologies historically evolved from random-scan (vector) to raster-scan systems. The question probes understanding of how rasterization and periodic refresh alter perceived flicker and drawing latency compared with stroke-by-stroke vector refresh.
Given Data / Assumptions:
Concept / Approach:Flicker arises when refresh of a given element is too infrequent. Slow updates occur when the system must retrace many vectors to redraw a frame. Raster scanning uses a frame buffer and constant-rate scan-out, which stabilizes brightness and reduces flicker while also avoiding per-vector redrawing delays.
Step-by-Step Solution:
1) Identify vector refresh cost: more primitives mean longer refresh cycles and visible flicker.2) Recognize raster approach: store pixels in a frame buffer and scan out at a fixed frequency.3) Evaluate effects: constant refresh reduces flicker, and pixel-based updates avoid the stroke-by-stroke slow update bottleneck.4) Conclude: raster scanning eliminates both flicker and slow update that limited early vector displays.Verification / Alternative check:Contemporary displays use fixed refresh rates and double buffering to keep luminance steady and updates smooth, confirming reduction in flicker and delay.
Why Other Options Are Wrong:
Common Pitfalls:Confusing raster refresh with low refresh rate scenarios, overlooking double buffering, and assuming vector systems scale linearly with scene complexity without visual penalties.
Final Answer:flicker and slow update
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