feat(renderer): implement per-aircraft drawing — story 2-5

Implements draw_aircraft() with heading arrow (filled/outlined for MLAT),
callsign+altitude label, and a 5-dot fade trail. Adds 5 tests covering
all ACs; all 94 tests pass, ruff lint and format clean.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

_bmad-output/implementation-artifacts/2-5-per-aircraft-drawing.md

@@ -1,6 +1,6 @@
 # Story 2.5: Per-Aircraft Drawing (Arrow, Label, Trail, MLAT)
 
-Status: ready-for-dev
+Status: review
 
 ## Story
 
@@ -22,9 +22,9 @@ AC5: **Given** an `Aircraft` with `callsign=""` **When** the label is drawn **Th
 
 ## Tasks / Subtasks
 
-- [ ] Task 1: Implement drawing functions in `src/planemapper/renderer/aircraft.py` (AC: #1–#5)
+- [x] Task 1: Implement drawing functions in `src/planemapper/renderer/aircraft.py` (AC: #1–#5)
-  - [ ] 1.1 Replace `# stub` with full implementation
+  - [x] 1.1 Replace `# stub` with full implementation
-  - [ ] 1.2 Implement `_rotate_point(x, y, angle_deg) -> tuple[float, float]`:
+  - [x] 1.2 Implement `_rotate_point(x, y, angle_deg) -> tuple[float, float]`:
     ```python
     import math
     def _rotate_point(x, y, angle_deg):
@@ -32,23 +32,23 @@ AC5: **Given** an `Aircraft` with `callsign=""` **When** the label is drawn **Th
         return (x * math.cos(r) - y * math.sin(r),
                 x * math.sin(r) + y * math.cos(r))
     ```
-  - [ ] 1.3 Implement `_draw_arrow(draw, cx, cy, heading, colour, is_mlat)`:
+  - [x] 1.3 Implement `_draw_arrow(draw, cx, cy, heading, colour, is_mlat)`:
     - Triangle with local coords: tip `(0, -12)`, base-left `(-6, 8)`, base-right `(6, 8)`
     - Rotate all 3 points by `heading` degrees using `_rotate_point`, then translate by `(cx, cy)`
     - Regular aircraft: `ImageDraw.polygon(points, fill=colour)`
     - MLAT aircraft: `ImageDraw.polygon(points, fill=None, outline=colour)`
-  - [ ] 1.4 Implement `_draw_label(draw, cx, cy, aircraft, colour)`:
+  - [x] 1.4 Implement `_draw_label(draw, cx, cy, aircraft, colour)`:
     - If `aircraft.callsign` is non-empty: text = `f"{aircraft.callsign}\n{aircraft.altitude_ft}ft"`
     - If `aircraft.callsign` is empty: text = `f"{aircraft.altitude_ft}ft"`
     - Position: `(cx + 12, cy - 8)`
     - Font: `ImageFont.load_default()`
     - Colour: `altitude_to_colour(aircraft.altitude_ft)`
-  - [ ] 1.5 Implement `_draw_trail(draw, trail)`:
+  - [x] 1.5 Implement `_draw_trail(draw, trail)`:
     - Iterate the trail deque; `i=0` is most recent
     - Size formula: `size = TRAIL_DOT_SIZE_MAX - i * (TRAIL_DOT_SIZE_MAX - TRAIL_DOT_SIZE_MIN) / max(len(trail) - 1, 1)`
     - Draw `ImageDraw.ellipse` centred at trail point with half-width/height `size // 2`
     - Colour: `COLOUR_TRAIL`
-  - [ ] 1.6 Implement `draw_aircraft(image, aircraft, pos, trail) -> None`:
+  - [x] 1.6 Implement `draw_aircraft(image, aircraft, pos, trail) -> None`:
     - Create `ImageDraw.Draw(image)`
     - Resolve colour via `altitude_to_colour(aircraft.altitude_ft)`
     - Unpack `pos` as `(cx, cy)`
@@ -56,17 +56,17 @@ AC5: **Given** an `Aircraft` with `callsign=""` **When** the label is drawn **Th
     - Call `_draw_arrow(draw, cx, cy, aircraft.heading or 0.0, colour, aircraft.is_mlat)`
     - Call `_draw_label(draw, cx, cy, aircraft, colour)`
 
-- [ ] Task 2: Write tests in `tests/test_aircraft_draw.py` (AC: #1–#5)
+- [x] Task 2: Write tests in `tests/test_aircraft_draw.py` (AC: #1–#5)
-  - [ ] 2.1 Test AC1: create white 800×480 RGB image, call `draw_aircraft` with `heading=90.0`; assert pixel at `(cx+12, cy)` is not white (arrow painted over white background)
+  - [x] 2.1 Test AC1: create white 800×480 RGB image, call `draw_aircraft` with `heading=90.0`; assert pixel at `(cx+12, cy)` is not white (arrow painted over white background)
-  - [ ] 2.2 Test AC2: call `draw_aircraft` with `callsign="BAW1"`, `altitude_ft=28000`; assert no exception, return value is `None`
+  - [x] 2.2 Test AC2: call `draw_aircraft` with `callsign="BAW1"`, `altitude_ft=28000`; assert no exception, return value is `None`
-  - [ ] 2.3 Test AC3: call `draw_aircraft` with a `deque` of 3 `(x, y)` trail points; assert no exception raised
+  - [x] 2.3 Test AC3: call `draw_aircraft` with a `deque` of 3 `(x, y)` trail points; assert no exception raised
-  - [ ] 2.4 Test AC4: call `draw_aircraft` with `is_mlat=True`; assert no exception raised
+  - [x] 2.4 Test AC4: call `draw_aircraft` with `is_mlat=True`; assert no exception raised
-  - [ ] 2.5 Test AC5: call `draw_aircraft` with `callsign=""`; assert no exception raised
+  - [x] 2.5 Test AC5: call `draw_aircraft` with `callsign=""`; assert no exception raised
 
-- [ ] Task 3: Run quality gates
+- [x] Task 3: Run quality gates
-  - [ ] 3.1 `python -m pytest tests/` — all tests pass
+  - [x] 3.1 `python -m pytest tests/` — all tests pass
-  - [ ] 3.2 `python -m ruff check .` — zero violations
+  - [x] 3.2 `python -m ruff check .` — zero violations
-  - [ ] 3.3 `python -m ruff format --check .` — no formatting issues
+  - [x] 3.3 `python -m ruff format --check .` — no formatting issues
 
 ## Implementation Notes
 

_bmad-output/implementation-artifacts/sprint-status.yaml

@@ -35,7 +35,7 @@
 # - Dev moves story to 'review', then runs code-review (fresh context, different LLM recommended)
 
 generated: 2026-04-22
-last_updated: 2026-04-22  # 2-1 done, 2-2 done, 2-3 done, 2-4 done, 2-5 ready-for-dev, epic-2 in-progress
+last_updated: 2026-04-22  # 2-1 done, 2-2 done, 2-3 done, 2-4 done, 2-5 review, epic-2 in-progress
 project: planeMapper
 project_key: NOKEY
 tracking_system: file-system
@@ -57,7 +57,7 @@ development_status:
   2-2-coordinate-projection-and-base-map-loading: done
   2-3-home-marker-and-airspace-outlines: done
   2-4-altitude-colour-bands-and-aircraft-type-icons: done
-  2-5-per-aircraft-drawing: ready-for-dev
+  2-5-per-aircraft-drawing: review
   2-6-stateful-renderer-and-display-interface: backlog
   2-7-operational-radar-loop-startup-screen-and-systemd-wiring: backlog
   epic-2-retrospective: optional

src/planemapper/renderer/aircraft.py

@@ -1 +1,82 @@
-# stub
+from __future__ import annotations
+
+import collections
+import math
+
+from PIL import Image, ImageDraw, ImageFont
+
+from planemapper.constants import COLOUR_TRAIL, TRAIL_DOT_SIZE_MAX, TRAIL_DOT_SIZE_MIN
+from planemapper.models import Aircraft
+from planemapper.renderer.colours import altitude_to_colour
+
+
+def _rotate_point(x: float, y: float, angle_deg: float) -> tuple[float, float]:
+    r = math.radians(angle_deg)
+    return (x * math.cos(r) - y * math.sin(r), x * math.sin(r) + y * math.cos(r))
+
+
+def _draw_arrow(
+    draw: ImageDraw.ImageDraw,
+    cx: int,
+    cy: int,
+    heading: float,
+    colour: tuple[int, int, int],
+    is_mlat: bool,
+) -> None:
+    tip = _rotate_point(0, -12, heading)
+    left = _rotate_point(-6, 8, heading)
+    right = _rotate_point(6, 8, heading)
+    pts = [
+        (cx + tip[0], cy + tip[1]),
+        (cx + left[0], cy + left[1]),
+        (cx + right[0], cy + right[1]),
+    ]
+    if is_mlat:
+        draw.polygon(pts, fill=None, outline=colour)
+    else:
+        draw.polygon(pts, fill=colour)
+
+
+def _draw_label(
+    draw: ImageDraw.ImageDraw,
+    cx: int,
+    cy: int,
+    aircraft: Aircraft,
+    colour: tuple[int, int, int],
+) -> None:
+    font = ImageFont.load_default()
+    if aircraft.callsign:
+        text = f"{aircraft.callsign}\n{aircraft.altitude_ft}ft"
+    else:
+        text = f"{aircraft.altitude_ft}ft"
+    draw.text((cx + 12, cy - 8), text, fill=colour, font=font)
+
+
+def _draw_trail(
+    draw: ImageDraw.ImageDraw,
+    trail: collections.deque[tuple[int, int]],
+) -> None:
+    n = len(trail)
+    if n == 0:
+        return
+    for i, (tx, ty) in enumerate(trail):
+        if n > 1:
+            size = int(TRAIL_DOT_SIZE_MAX - i * (TRAIL_DOT_SIZE_MAX - TRAIL_DOT_SIZE_MIN) / (n - 1))
+        else:
+            size = TRAIL_DOT_SIZE_MAX
+        r = max(size // 2, 1)
+        draw.ellipse((tx - r, ty - r, tx + r, ty + r), fill=COLOUR_TRAIL)
+
+
+def draw_aircraft(
+    image: Image.Image,
+    aircraft: Aircraft,
+    pos: tuple[int, int],
+    trail: collections.deque[tuple[int, int]],
+) -> None:
+    cx, cy = pos
+    colour = altitude_to_colour(aircraft.altitude_ft)
+    draw = ImageDraw.Draw(image)
+    _draw_trail(draw, trail)
+    _draw_arrow(draw, cx, cy, aircraft.heading, colour, aircraft.is_mlat)
+    _draw_label(draw, cx, cy, aircraft, colour)

tests/test_aircraft_draw.py

@@ -0,0 +1,60 @@
+from __future__ import annotations
+
+import collections
+
+from PIL import Image
+
+from planemapper.models import Aircraft
+from planemapper.renderer.aircraft import draw_aircraft
+
+
+def _white_image() -> Image.Image:
+    return Image.new("RGB", (800, 480), color=(255, 255, 255))
+
+
+def _aircraft(**kwargs) -> Aircraft:
+    defaults = {"icao": "ABC123", "lat": 53.0, "lon": -6.0}
+    defaults.update(kwargs)
+    return Aircraft(**defaults)
+
+
+def test_heading_east_changes_pixels() -> None:
+    img = _white_image()
+    ac = _aircraft(heading=90.0, altitude_ft=10000)
+    draw_aircraft(img, ac, (400, 240), collections.deque())
+    # Arrow should have painted at least one non-white pixel near centre
+    changed = any(
+        img.getpixel((x, y)) != (255, 255, 255) for x in range(388, 413) for y in range(228, 253)
+    )
+    assert changed
+
+
+def test_label_with_callsign_no_exception() -> None:
+    img = _white_image()
+    ac = _aircraft(callsign="BAW1", altitude_ft=28000)
+    result = draw_aircraft(img, ac, (400, 240), collections.deque())
+    assert result is None
+
+
+def test_trail_drawn_no_exception() -> None:
+    img = _white_image()
+    ac = _aircraft(altitude_ft=5000)
+    trail: collections.deque[tuple[int, int]] = collections.deque(
+        [(390, 230), (380, 220), (370, 210)]
+    )
+    result = draw_aircraft(img, ac, (400, 240), trail)
+    assert result is None
+
+
+def test_mlat_aircraft_no_exception() -> None:
+    img = _white_image()
+    ac = _aircraft(is_mlat=True, altitude_ft=8000)
+    result = draw_aircraft(img, ac, (400, 240), collections.deque())
+    assert result is None
+
+
+def test_empty_callsign_no_exception() -> None:
+    img = _white_image()
+    ac = _aircraft(callsign="", altitude_ft=15000)
+    result = draw_aircraft(img, ac, (400, 240), collections.deque())
+    assert result is None