feat(ggplot2): implement polar-bar

[github-actions]

Implementation: polar-bar - r/ggplot2

Implements the r/ggplot2 version of polar-bar.

File: plots/polar-bar/implementations/r/ggplot2.R

Parent Issue: #2693

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

Light render (plot-light.png): Warm off-white background (#FAF8F1-consistent). Title "polar-bar · r · ggplot2 · anyplot.ai" is dark and centered, clearly legible. All 16 compass-direction labels (N, NNE, NE, ... NNW) render in medium-grey ink around a large implied circle and are readable. The "0%/5%/10%" radial labels appear as a small stacked column at upper-left, disconnected from any visible grid ring (gridlines are turned off). The "Wind speed" legend at the bottom is correct with 5 labeled swatches. The colored wedges themselves (green/lavender/blue/ochre/red stacked per direction) occupy only roughly a third of the available radius, clearly showing prevailing-westerly weighting (large SW/WSW/W wedges, small N/NE), but the innermost ochre/red segments are nearly invisible at this scale. All text is readable against the light background.

Dark render (plot-dark.png): Same layout on a warm near-black background (#1A1A17-consistent). Title, compass labels, and legend all flip to light ink and remain fully readable — no dark-on-dark failures. Data wedge colors are identical to the light render (only chrome flipped), confirming palette consistency. The same small, off-scale rose and near-invisible top-speed-bin segments persist.

Both renders are theme-correct text-wise, but both share the same structural weakness: the data occupies a small fraction of the canvas while its own axis labels are spread across a much larger implied circle, leaving a large disconnected band of empty space.

Score: 75/100

Category	Score	Max
Visual Quality	22	30
Design Excellence	8	20
Spec Compliance	15	15
Data Quality	13	15
Code Quality	10	10
Library Mastery	7	10
Total	75	100

Visual Quality (22/30)

• VQ-01: Text Legibility (6/8)
• VQ-02: No Overlap (6/6)
• VQ-03: Element Visibility (4/6)
• VQ-04: Color Accessibility (2/2)
• VQ-05: Layout & Canvas (0/4) - Wind-rose wedges fill well under 30% of the canvas; a large disconnected empty band sits between the bars and the outer compass-label ring
• VQ-06: Axis Labels & Title (2/2)
• VQ-07: Palette Compliance (2/2)

Design Excellence (8/20)

• DE-01: Aesthetic Sophistication (2/8) - Correct palette/technique choice undermined by the severe layout problem
• DE-02: Visual Refinement (2/6) - No radial grid rings to anchor the % labels; default-level refinement
• DE-03: Data Storytelling (4/6) - Clear prevailing-wind hierarchy visible despite the layout issue

Spec Compliance (15/15)

• SC-01: Plot Type (5/5)
• SC-02: Required Features (4/4)
• SC-03: Data Mapping (3/3)
• SC-04: Title & Legend (3/3)

Data Quality (13/15)

• DQ-01: Feature Coverage (4/6) - Top two speed bins barely register visually
• DQ-02: Realistic Context (5/5)
• DQ-03: Appropriate Scale (4/4)

Code Quality (10/10)

• CQ-01: KISS Structure (3/3)
• CQ-02: Reproducibility (2/2)
• CQ-03: Clean Imports (2/2)
• CQ-04: Code Elegance (2/2)
• CQ-05: Output & API (1/1)

Library Mastery (7/10)

• LM-01: Idiomatic Usage (4/5)
• LM-02: Distinctive Features (3/5) - coord_polar(theta = "x") with custom start angle

Score Caps Applied

• DE-01 ≤ 2 AND DE-02 ≤ 2 ("correct but boring" cap) → max 75

Strengths

• Correct plot type: a true polar stacked bar / wind rose using coord_polar(theta = "x") with geom_col, covering all 16 compass directions and 5 stacked wind-speed bins per the spec notes.
• Palette compliance: first (and largest) series is exactly #009E73, remaining series follow canonical Imprint order, identical across both renders.
• Theme-adaptive chrome works correctly in both renders — no dark-on-dark or light-on-light failures.
• Title format matches exactly; legend is accurate and well-labeled.
• Realistic, neutral, factually plausible meteorological scenario (prevailing westerlies).
• Clean, reproducible, idiomatic KISS-structured R script.

Weaknesses

• Severe canvas under-utilization: the colored wedges only span ~30-35% of the plot's diameter (~8-10% of canvas area) while the compass-direction labels sit on a much larger implied ring far outside the bars, leaving a large disconnected empty band between the data and its own axis labels. Reduce scale_y_continuous's expansion / axis.text.x margin so direction labels sit closer to the bars, and/or increase geom_col extent / figure scale so the rose fills 50-80% of the canvas.
• No radial grid rings are drawn (panel.grid.major/minor are element_blank()), so the "0%/5%/10%" labels float without a visual reference circle. Add faint theme-adaptive panel.grid.major lines so the percentage rings are visible in both themes.
• The two highest wind-speed categories (15-20 kt, 20+ kt) are reduced to near-invisible slivers near the center in both renders.
• Design excellence is capped by the layout problem: the plot reads as a well-configured default rather than a polished, publication-ready wind rose.

Issues Found

1. VQ-05 SEVERE: Wind-rose wedges fill well under 30% of canvas area, disconnected from the outer compass-label ring
   • Fix: Tighten scale_y_continuous(expand=...) and axis.text.x margins, and/or enlarge the rose so it fills 50-80% of the canvas per the style guide's Canvas Utilization Rules.
2. DE-02 LOW: No radial grid rings for the percentage scale
   • Fix: Add subtle panel.grid.major = element_line(color = INK, linewidth = 0.2) (or similar theme-adaptive faint line) so readers can gauge bar length against the 0%/5%/10% labels.
3. VQ-03 / DQ-01 LOW: 15-20kt and 20+kt segments are nearly invisible
   • Fix: Consider a minimum visible arc thickness or accept as a known limitation of the chosen data distribution, but note it in the weaknesses.

AI Feedback for Next Attempt

The core technique (coord_polar wind rose) and palette are correct — the main fix is proportion: make the wind rose itself fill most of the canvas (50-80%) instead of floating as a small disconnected shape inside a much larger ring of compass labels. Restore a faint theme-adaptive radial grid so the 0%/5%/10% labels have a visual reference, and tighten the axis-label margins so direction labels sit close to the bar tips rather than far outside them.

Verdict: REJECTED

[github-actions]

🔧 Repair Attempt 1/4

Applied fixes based on AI review feedback.

Status: Repair completed, re-triggering review...

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🤖 impl-repair

[claude]

AI Review - Attempt 2/3

Image Description

Light render (plot-light.png): Warm off-white background (#FAF8F1-consistent). Title "polar-bar · r · ggplot2 · anyplot.ai" is dark ink, centered, fully legible. All 16 compass-direction labels (N, NNE, NE, ... NNW) render in medium-grey ink and are readable. A faint radial grid (0%/5%/10% rings) is now visible, anchoring the axis labels which sit along the W spoke. The "Wind speed" legend at the bottom is correct with 5 labeled swatches. Stacked wedges (green/lavender/blue/ochre/red, in Imprint order) radiate from the center and now extend most of the way to the outer ring — a clear improvement over attempt 1's under-filled rose. The prevailing-westerly weighting (large SW/WSW/W wedges, small N/NE/ENE) is obvious, and thanks to reverse stacking the higher-speed bins (ochre, red) sit on the outside and stay visible even for small directions. All text is readable against the light background, and nothing is clipped at any canvas edge.

Dark render (plot-dark.png): Same layout on a warm near-black background (#1A1A17-consistent). Title, compass labels, radial grid, tick labels, and legend all flip to light ink/grey and remain fully readable — no dark-on-dark failures anywhere, including the small-direction wedge outlines. Data wedge colors are identical to the light render (only chrome flipped), confirming palette consistency. Brand green remains clearly visible on both surfaces.

Both renders are theme-correct and, unlike attempt 1, the data itself now occupies a large, well-proportioned share of the canvas with a visible reference grid.

Score: 90/100

Category	Score	Max
Visual Quality	27	30
Design Excellence	15	20
Spec Compliance	15	15
Data Quality	14	15
Code Quality	10	10
Library Mastery	9	10
Total	90	100

Visual Quality (27/30)

• VQ-01: Text Legibility (7/8)
• VQ-02: No Overlap (6/6)
• VQ-03: Element Visibility (5/6)
• VQ-04: Color Accessibility (2/2)
• VQ-05: Layout & Canvas (3/4) - Canvas utilization fixed from attempt 1; minor crowding where 0%/5%/10% labels sit next to the W compass label
• VQ-06: Axis Labels & Title (2/2)
• VQ-07: Palette Compliance (2/2)

Design Excellence (15/20)

• DE-01: Aesthetic Sophistication (6/8) - Custom Imprint palette plus a deliberate reverse-stacking technique to solve a real visibility problem
• DE-02: Visual Refinement (4/6) - Radial grid restored, clean legend, still fairly close to theme_minimal defaults
• DE-03: Data Storytelling (5/6) - Clear focal point on SW/W prevailing wind with strong visual hierarchy

Spec Compliance (15/15)

• SC-01: Plot Type (5/5)
• SC-02: Required Features (4/4)
• SC-03: Data Mapping (3/3)
• SC-04: Title & Legend (3/3)

Data Quality (14/15)

• DQ-01: Feature Coverage (5/6) - All 5 speed bins now visible at every direction; extreme low-frequency directions still thin
• DQ-02: Realistic Context (5/5)
• DQ-03: Appropriate Scale (4/4)

Code Quality (10/10)

• CQ-01: KISS Structure (3/3)
• CQ-02: Reproducibility (2/2)
• CQ-03: Clean Imports (2/2)
• CQ-04: Code Elegance (2/2)
• CQ-05: Output & API (1/1)

Library Mastery (9/10)

• LM-01: Idiomatic Usage (5/5)
• LM-02: Distinctive Features (4/5) - position_stack(reverse = TRUE) combined with clip = "off" is a genuinely distinctive, well-reasoned technique

Score Caps Applied

• None

Strengths

• Canvas utilization is fixed from attempt 1: the wind-rose wedges now extend most of the way to the outer gridline, filling the square canvas convincingly.
• position_stack(reverse = TRUE) is a smart, well-commented fix that keeps the thin high-speed bins visible at every direction instead of collapsing near the center.
• Faint theme-adaptive radial grid now gives the 0%/5%/10% labels a visual reference circle in both renders.
• Correct plot type, all required features (16 directions, 5 stacked speed bins, color encoding), theme-adaptive chrome flawless in both renders.
• Realistic, neutral meteorological scenario (prevailing westerlies); clean, reproducible, idiomatic KISS-structured R script.

Weaknesses

• The 0%/5%/10% radial axis labels cluster together right along the W spoke (a ggplot2 coord_polar quirk), sitting close to the "W" compass label — slightly crowds that corner even though no text actually overlaps.
• The lightest-frequency directions (NE, ENE, E) still render very thin wedges where individual speed-bin segments are only a few pixels tall.
• Design excellence is solid but not yet distinctive beyond the reverse-stack trick.

Issues Found

1. VQ-05 MINOR: 0%/5%/10% axis labels crowd the W compass label
   • Fix: Consider nudging axis.text.y margin or accepting as a known ggplot2 coord_polar limitation — not severe enough to require another repair pass.
2. DQ-01 MINOR: NE/ENE/E wedges are very thin
   • Fix: Acceptable as a realistic consequence of the prevailing-westerlies data story; no action required.

AI Feedback for Next Attempt

No further repair needed — attempt 2 resolved all attempt-1 blockers (canvas utilization, missing radial grid, invisible high-speed bins). Future polish ideas if revisited: reduce crowding between the radial % labels and the W compass label, and consider a minimum visible arc thickness for the calmest directions.

Verdict: APPROVED