ChevronProcess Component

The ChevronProcess component draws horizontal, sequential process pipelines consisting of interlocking arrowhead blocks (chevrons). It is the premier component for CI/CD delivery pipelines, phased development milestones, fulfillment lifecycles, and multi-step workflows.

from drawlib.canvas import save, setup
from drawlib.icons import phosphor
from drawlib.smartarts import ChevronProcess
from drawlib.styles import Styles
from drawlib.text import text

setup(width=128, height=56)

# 1. Top Row: Flat-Start Chevron Pipeline (flat_left_end=True, corner_angle=60.0)
text((5, 50.5), "1. Flat-Start Pipeline (flat_left_end=True, corner_angle=60.0)", style=Styles.DarkBold.patch(text_size=10.5, halign="left"))

# Stage icons above each chevron
phosphor.file_text(xy=(16.5, 42.8), width=3.8, style=Styles.DarkBold)
phosphor.gear(xy=(46.0, 42.8), width=3.8, style=Styles.PrimaryBold)
phosphor.shield_check(xy=(75.5, 42.8), width=3.8, style=Styles.PrimaryFlat)
phosphor.rocket_launch(xy=(105.0, 42.8), width=3.8, style=Styles.SecondaryBold)

flat_pipe = ChevronProcess(
    style=Styles.Neutral,
    text_style=Styles.DarkBold.patch(text_size=10.5),
    description_style=Styles.Dark.patch(text_size=10.0),
    corner_angle=60.0,
    spacing=2.0,
    flat_left_end=True,
)
flat_pipe.add("1. Plan", description="RFC & Design")
flat_pipe.add("2. Build", description="Compile & Test", style=Styles.PrimaryNeutral)
flat_pipe.add(
    "3. Verify",
    description="Canary Gate",
    style=Styles.PrimaryFlat,
    text_style=Styles.WhiteBold.patch(text_size=10.5),
    description_style=Styles.White.patch(text_size=10.0),
)
flat_pipe.add("4. Release", description="Global Rollout", style=Styles.SecondaryNeutral)
flat_pipe.draw(xy=(5, 27.5), width=118.0, height=13.5)

# 2. Bottom Row: Classic Indented Chevrons (flat_left_end=False, corner_angle=45.0)
text((5, 21.0), "2. Classic Indented Chevrons (flat_left_end=False, corner_angle=45.0)", style=Styles.DarkBold.patch(text_size=10.5, halign="left"))

indented_pipe = ChevronProcess(
    style=Styles.Neutral,
    text_style=Styles.DarkBold.patch(text_size=10.5),
    description_style=Styles.Dark.patch(text_size=10.0),
    corner_angle=45.0,
    spacing=2.0,
    flat_left_end=False,
)
indented_pipe.add("1. Ingest", description="Event Stream")
indented_pipe.add("2. Cleanse", description="Schema Check", style=Styles.SecondaryNeutral)
indented_pipe.add("3. Enrich", description="Feature Join", style=Styles.PrimaryNeutral)
indented_pipe.add("4. Serve", description="Data Mart")
indented_pipe.draw(xy=(5, 4.0), width=118.0, height=13.5)

save()

1. Quick Example: CI/CD Pipeline

from drawlib.canvas import setup
from drawlib.smartarts import ChevronProcess
from drawlib.styles import Styles

setup(width=128, height=34)

pipeline = ChevronProcess(
    style=Styles.Neutral,
    text_style=Styles.DarkBold.patch(text_size=10.5),
    description_style=Styles.Dark.patch(text_size=10.0),
    corner_angle=60.0,
    spacing=2.0,
    flat_left_end=True,
)
pipeline.add("1. Commit", description="Lint & Test")
pipeline.add("2. Build", description="Docker Image")
pipeline.add(
    "3. Security",
    description="Vuln Scan",
    style=Styles.PrimaryFlat,
    text_style=Styles.WhiteBold.patch(text_size=10.5),
    description_style=Styles.White.patch(text_size=10.0),
)
pipeline.add("4. Staging", description="E2E Checks")
pipeline.add("5. Release", description="Canary", style=Styles.SecondaryNeutral)

pipeline.draw(xy=(5, 8), width=118.0, height=18.0)

2. Classic Indented Chevrons with Explicit item_width & corner_angle

Setting flat_left_end=False (the default) renders every stage—including the first—as a classic indented chevron, while passing an explicit item_width to draw(...) gives every stage an exact fixed body width instead of auto-dividing a bounding container width. You can also adjust corner_angle (valid range: 10.0 to 80.0 degrees) to control arrowhead sharpness, and mutate returned ChevronItem instances before drawing.

from drawlib.canvas import save, setup
from drawlib.smartarts import ChevronProcess
from drawlib.styles import Styles

setup(width=126, height=34)

etl = ChevronProcess(
    style=Styles.Neutral,
    text_style=Styles.DarkBold.patch(text_size=10.5),
    description_style=Styles.Dark.patch(text_size=10.0),
    corner_angle=45.0,
    spacing=2.5,
    flat_left_end=False,
)

etl.add("1. Ingest", description="Kafka Stream", style=Styles.PrimaryNeutral)
transform_stage = etl.add("2. Cleanse", description="Schema Check")
etl.add("3. Enrich", description="Feature Join", style=Styles.SecondaryNeutral)
etl.add("4. Serve", description="Parquet Lake")

# Mutate a ChevronItem (or access via etl.items[1]) before calling draw()
transform_stage.style = Styles.PrimaryFlat
transform_stage.text_style = Styles.WhiteBold.patch(text_size=10.5)
transform_stage.description_style = Styles.White.patch(text_size=10.0)

etl.draw(xy=(6.5, 8.0), height=18.0, item_width=24.0)
save()

3. Geometry & Coordinate Anchor

• Bottom-Left Anchor (x, y): The coordinate passed to draw(xy=...) represents the bottom-left corner of the entire process bounding box.
• flat_left_end:
  • False (default): All stages—including the first—have an indented left notch matching the arrowhead tip angle.
  • True: The first chevron is drawn as a flat-backed pentagon with a clean vertical left border.
• corner_angle: Angle of the arrowhead tip in degrees (valid range: 10.0 to 80.0, default 60.0). Lower angles (45.0) produce deeper, sharper arrowheads; higher angles (70.0) produce flatter tips.
• Automatic vs. Explicit Stage Width (width vs. item_width):
  • When item_width=None (default), draw() automatically calculates each stage's body width from the total width, spacing, and arrowhead indent ($x_{\text{indent}} = \frac{\text{height}/2}{\tan(\text{corner_angle})}$): $$\text{item_width} = \frac{\text{width} - (N - 1) \cdot \text{spacing} - x_{\text{indent}}}{N}$$
  • When item_width is explicitly provided, width is ignored and each stage uses item_width directly.

4. API Reference

Constructor (ChevronProcess)

ChevronProcess(
    *,
    style: Style,
    text_style: Style,
    description_style: Style,
    corner_angle: float = 60.0,
    spacing: float = 1.5,
    flat_left_end: bool = False,
)

Adding & Inspecting Stages (.add() & .items)

pipeline.add(
    text: str,
    *,
    description: str = "",
    style: Style | None = None,
    text_style: Style | None = None,
    description_style: Style | None = None,
    show: bool = True,
) -> ChevronItem

• pipeline.items -> list[ChevronItem]: Returns the list of registered ChevronItem instances in order.
• ChevronItem Model Fields: Each returned item exposes mutable attributes resolved at draw() time:
  • text: str
  • style: Style
  • text_style: Style
  • description_style: Style
  • description: str = ""
  • show: bool = True

Drawing (.draw())

pipeline.draw(
    xy: tuple[float, float],
    width: float = 90.0,
    height: float = 12.0,
    item_width: float | None = None,
    scale: float = 1.0,
) -> None