Fabric Calculation Engine

Industry-standard algorithms for precise fabric calculations.

Calculation Philosophy:
All calculations originate from a centralized engine (calculationFormulas.ts) ensuring 100% consistency across quotes, work orders, and invoices.

Single Source of Truth:

• Calculate once in the engine
• Pass results to all display components
• Never recalculate in display logic
• Prevents '2+2=5' errors

Fabric Orientation:

Vertical (Standard):
Fabric runs top-to-bottom (normal orientation)

• Widths calculated from rail width × fullness
• Pieces needed = widths ÷ fabric width
• Total meterage = pieces × drop length

Horizontal (Railroaded):
Fabric runs side-to-side (rotated 90°)

• Pieces calculated from drop ÷ fabric width
• Each piece spans full width
• Total meterage = pieces × total width

Included in Calculations:

• Window dimensions
• Fullness ratios (from heading/template)
• Header and bottom hems
• Side hem allowances
• Return dimensions (left/right)
• Seam allowances (critical!)
• Pattern repeat matching
• Wastage percentage

Display Format:

• Vertical: 'X.XXm × $XX.XX/m'
• Horizontal: 'X.XXm × Y pieces = Z.ZZm × $XX.XX/m'