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🥽 VR research: use computation where people need it

Keep the details users need, and reuse work shared by several users. My thesis connects eye-task recognition, rendering control, shared caches and client–edge communication into an evaluable system.

Research work Approach Results reported in the thesis
Task-aware rendering Task-aware detail and resolution Mean segment frame time: 10.14 → 5.40 ms
Shared cache reuse Shared blocks and learned scheduling Mean relative hit-rate gain: 22.08% across six system conditions
Integration Unity client + Python edge service + TCP Real-headset integration; 30-minute, 60-user simulated load

Results come from separate thesis experiments, with conditions explained below. Figures are public; code repositories remain private.

The system at a glance: task-aware clients, reusable content at the edge

Original thesis Figure 5-1: client–edge architecture
Original thesis Figure 5-1: client–edge architecture

Read the diagram: observe head/eye behavior → recognize the task and adjust rendering → send state and object-block requests to the edge → return cache decisions and results.

① Tasks and quality · ② Sharing and caches · ③ System results · ④ Implementation and figures

Part Plain-language question Work
Client Which details matter for the current task? Head/eye observations, task classification, foveation control
Edge Has another user just needed the same content? Shared object blocks, grouping, retention, admission, prefetch and eviction
Connection What information must the two sides exchange? State reports, object requests, decisions and cache feedback

These are the three stages in thesis Chapters 3–5: evaluate the methods, then integrate them. This page summarizes reported experiments; they were not rerun for this showcase. Original figure labels remain in Chinese.

① The same gaze point can require different rendering settings

Reading text, tracking a moving object and searching a scene require different detail and coverage. Foveated rendering divides the image into three regions; the task-aware method adjusts their size and resolution using the current task.

Original thesis Figure 3-6: fixation, pursuit, reading, search and browsing
Original thesis Figure 3-6: fixation, pursuit, reading, search and browsing
Step Input and output Purpose
Observe behavior A head/eye sequence A single gaze point does not describe the whole task
Recognize the task Probabilities for five task types Distinguish fixation, pursuit, reading, search and browsing
Allocate detail Center/transition size and peripheral resolution Keep resources where the current task needs them
Smooth changes Continuously adjusted parameters Reduce abrupt parameter changes
Original thesis Figure 3-5: center, transition and peripheral regions
Original thesis Figure 3-5: center, transition and peripheral regions

Evaluate quality and rendering cost together

Strategy Mean segment frame time Mean segment over-budget ratio Speed-up vs full resolution
Full resolution 10.14 ± 2.99 ms 33.42% 1.00×
SCFR baseline 5.58 ± 2.95 ms 6.09% 1.82×
TAFR task-aware strategy 5.40 ± 2.97 ms 4.81% 1.88×

Source: final thesis Table 3.7, printed page 48. Compute statistics within scene–route segments, then average across segments. The rendering speed-up does not describe the complete VR system’s end-to-end speed-up.

Original thesis Figure 3-14: image quality and local detail in the Fireplace scene
Original thesis Figure 3-14: image quality and local detail in the Fireplace scene

Quality is evaluated with PSNR, SSIM, LPIPS and FovVideoVDP. TAFR performs well on aggregate SSIM and LPIPS, but does not win every metric in every scene. The task classifier reports 93.85 ± 0.26% accuracy in sample-level five-fold cross-validation; this does not establish equivalent accuracy on entirely unseen users.

② What can users with overlapping views share?

Different positions and orientations can still expose the same object to several users. Object-block representations make overlap measurable, so shared value can inform cache scheduling.

Original thesis Figure 4-3: overlapping views and shared object blocks
Original thesis Figure 4-3: overlapping views and shared object blocks
Cache question Action
Is new content worth storing? Admission
What is likely to be reused by several users? Retention or prefetch
What should leave when capacity is exhausted? Eviction

SCOPE-DDQN learns these choices from state and feedback. Compare its benefit against rule-based methods such as LRU, and account for decision overhead and load. Additional algorithm complexity needs measured justification.

Original thesis Figure 4-9: cache hit rates in method experiments
Original thesis Figure 4-9: cache hit rates in method experiments

This is a Chapter 4 method experiment. The next section is a Chapter 5 integrated-system experiment. Request workflows and aggregation differ, so the numbers should not be combined into one performance curve.

③ How much benefit remains after integration?

Original thesis Figure 5-10: integrated-system comparison of LRU and SCOPE-DDQN
Original thesis Figure 5-10: integrated-system comparison of LRU and SCOPE-DDQN
Users and duration LRU hit rate SCOPE-DDQN hit rate LRU shared hit rate SCOPE-DDQN shared hit rate
10 · short 55.72% 64.22% 12.80% 18.51%
10 · long 53.30% 63.49% 12.32% 16.92%
20 · short 44.37% 58.47% 11.86% 18.47%
20 · long 45.79% 57.34% 11.94% 17.37%
60 · short 47.47% 57.55% 14.87% 21.63%
60 · long 47.12% 56.48% 15.10% 19.34%

Source: final thesis Table 5.4, printed page 84. Six paired conditions, two methods, 12 experiment groups. Multi-user requests are generated by a controlled simulation; real-headset integration verifies collection, rendering and communication.

A concrete example: in the 20-user short condition, 44.37% → 58.47% is 14.10 percentage points, or approximately 31.78% relative gain.

Summary across six paired conditions Mean relative gain Bootstrap 95% confidence interval
Cache hit rate 22.08% [18.31%, 26.51%]
Shared hit rate 42.78% [35.46%, 49.23%]

Source: final thesis Table 5.5, printed page 85. These are means of condition-wise relative gains, not mean percentage-point differences.

Observe a longer run

Original thesis Figure 5-12: window-level results for 60 simulated users over 30 minutes
Original thesis Figure 5-12: window-level results for 60 simulated users over 30 minutes

The window-level mean hit rate is 57.16%, with approximately 153.44 ms mean edge-processing proxy latency. This proxy measures server-side handling from request receipt to response creation. It is not network round-trip latency or headset end-to-end Motion-to-Photon latency. Window-level and whole-run hit-rate aggregation can differ.

④ Implementation and more original figures

Part Technologies and work
Client and scenes Unity 2022.3 LTS, C#, Pico 4 Enterprise integration, task-driven rendering parameters
Edge cache Python 3.10, PyTorch 2.1, dynamic grouping, shared object blocks, cache decisions
Communication TCP sockets, structured JSON, state reports and feedback
Evaluation Baselines, ablations, integrated-system comparisons, 30-minute runs
Expand communication, runtime examples and additional results

Exchanging state between client and edge

Original Figure 5-2: communication sequence and latency components
Original Figure 5-2: communication sequence and latency components

Rendering settings during execution

Original Figure 5-6: task-driven rendering
Original Figure 5-6: task-driven rendering

Shared opportunities as user groups change

Original Figure 5-7: dynamic grouping and shared-block heatmaps
Original Figure 5-7: dynamic grouping and shared-block heatmaps

Organizing cache decisions

Original Figure 4-4: SCOPE-DDQN decision model
Original Figure 4-4: SCOPE-DDQN decision model

Inspecting rendering cost and quality together

Original Figure 3-17: segment mean frame-time distributions
Original Figure 3-17: segment mean frame-time distributions
Original Figure 3-19: joint quality–efficiency evaluation
Original Figure 3-19: joint quality–efficiency evaluation

Relative gains across six system conditions

Original Figure 5-11: condition-wise relative gains
Original Figure 5-11: condition-wise relative gains

What the evidence supports, and what remains to evaluate

Supported by current experiments Further evaluation needed
Task recognition, rendering control and shared caching form a working chain Different devices, scenes and real users
Method and system experiments report quality, cost and cache benefits Cross-user generalization and decision overhead
Controlled multi-user loads permit cache and long-run comparisons Large real-user deployments, wireless variability and end-to-end experience

The work connects measurable modules and evaluates the resulting system, with separate definitions for each benefit and cost.

Original figure provenance and page numbers · Discuss via GitHub Issues