2D Bilinear Interpolation

Module defined in lua/common/interpolatedMap.lua. Provides 2D bilinear interpolation on structured data maps. Useful for looking up values in 2D tables like torque curves, gear ratio maps, etc.

Exports

Functions

interpolatedMap.new(interpolationMethod)

Creates a new 2D interpolated map instance.

• Parameters:
  • interpolationMethod - any - Currently unused (only bilinear is implemented)
• Returns: table - An interpolated map object

Instance Methods

map:loadData(inputData)

Loads a 2D data table in jbeam-style format. First row is X axis headers; subsequent rows have Y axis value as first element, then data values.

• Parameters:
  • inputData - table - 2D array in jbeam format (see example below)

Example input format:

{
  {0, 0.5, 1},           -- X axis: [0, 0.5, 1]
  {0, 0.5, 1, 1},        -- Y=0:  values at each X
  {7, 0.4, 0.9, 1},      -- Y=7:  values at each X
  {14, 0.3, 0.8, 1},     -- Y=14: values at each X
}

map:get(x, y)

Returns the bilinearly interpolated value at coordinates (x, y).

• Parameters:
  • x - number - X coordinate
  • y - number - Y coordinate
• Returns: number|nil - Interpolated value, or nil if out of range and clamping is disabled

map:reset()

Placeholder for future reset functionality (currently a no-op).

Instance Fields

map.clampToDataRange

• Type: boolean (default: false)
• Description: When true, out-of-range coordinates are clamped to the data bounds instead of returning nil

Internal Notes

• If the first row has the same length as the second row, the first element of row 1 is treated as a label and stripped
• Bilinear interpolation uses the standard formula from x-engineer.org
• Cache and precision options are planned but not yet implemented (TODO)

See Also

• cdefDebugDraw Reference - Related reference
• cdefGpuMesh Reference - Related reference
• cdefImgui Reference - Related reference
• Common Libraries Overview - Guide