3D Tables

Structures and functions related to 3D tables, such as VE, Spark Advance, AFR etc. More...

Files
file	table3d.h
	3D table data types and functions
file	table3d_axes.h
	3D table axis types and iterators
file	table3d_typedefs.h
	Typedefs for primitive 3D table elements.

Classes
struct	table3d_t

Typedefs
using	table3d_dim_t = uint8_t
	Encodes the length of the axes.
using	table3d_value_t = uint8_t
	The type of each table value.
using	table3d_axis_t = uint8_t
	The type of each axis value.

Enumerations
enum class	TableType : uint8_t { TableType::table_type_None }
	Table type identifiers. Limited compile time RTTI. More...
enum class	AxisDomain : uint8_t { AxisDomain::Rpm , AxisDomain::Load }
	Encodes the real world measurement that a table axis captures. More...

Functions
template<typename TTable >
struct TABLE3D_TYPENAME_BASE(6, Rpm, Load) struct TABLE3D_TYPENAME_BASE(4, Rpm, Load) struct TABLE3D_TYPENAME_BASE(8, Rpm, Load) struct static TABLE3D_TYPENAME_BASE(16, Rpm, Load) table3d_value_t	get3DTableValue (const TTable *pTable, const uint16_t y, const uint16_t x)
	A 3D table with 6 x 6 dimensions, Rpm x-axis and Load y-axis.
static constexpr uint16_t	getConversionFactor (AxisDomain domain)

Detailed Description

Structures and functions related to 3D tables, such as VE, Spark Advance, AFR etc.

Logical:

• each 3D table is a continuous height map spread over a cartesian (x, y) plane
  • Continuous: we expect to interpolate between any 4 points
• The axes are
  • Bounded. I.e. non-infinite
  • Non-linear. I.e. x[n]-x[n-1] != x[n+1]-x[n]
  • Increasing. I.e. x[n] >= x[n-1]
  • Do not have to start at [0,0]

E.g. for a 3x3 table, this is what the TS table editor would show:

     Y-Max    V6      V7      V8
     Y-Int    V3      V4      V5
     Y-Min    V0      V1      V2
             X-Min   X-Int   X-Max

In memory, we store rows in reverse:

• Both axes are inverted:
  • x[0] stores X-Max
  • x[2] stores X-Min
  • y[0] stores Y-Max
  • y[2] stores Y-Min
• The value locations match the axes.
  • value[0][0] stores V6.
  • value[2][0] stores V0.

I.e.

     Y-Min    V0      V1      V2
     Y-Int    V3      V4      V5
     Y-Max    V6      V7      V8
             X-Min   X-Int   X-Max

Typedef Documentation

table3d_axis_t

using table3d_axis_t = uint8_t

The type of each axis value.

table3d_dim_t

using table3d_dim_t = uint8_t

Encodes the length of the axes.

table3d_value_t

using table3d_value_t = uint8_t

The type of each table value.

Enumeration Type Documentation

AxisDomain

enum class AxisDomain : uint8_t

strong

Encodes the real world measurement that a table axis captures.

Enumerator
Rpm	RPM (engine speed)
Load	Load

TableType

enum class TableType : uint8_t

strong

Table type identifiers. Limited compile time RTTI.

With no virtual functions (they have quite a bit of overhead in both space & time), we have to pass void* around in certain cases. In order to cast that back to a concrete table type, we need to somehow identify the type.

Once approach is to register each type - but that requires a central registry which will use RAM.

Since we have a compile time fixed set of table types, we can map a unique identifier to the type via a cast - this enum is that unique identifier.

Typically used in conjunction with visitTable3d()

Enumerator
table_type_None

Function Documentation

get3DTableValue()

template<typename TTable >

struct TABLE3D_TYPENAME_BASE(6, Rpm, Load) struct TABLE3D_TYPENAME_BASE(4, Rpm, Load) struct TABLE3D_TYPENAME_BASE(8, Rpm, Load) struct static TABLE3D_TYPENAME_BASE(16, Rpm, Load) table3d_value_t get3DTableValue ( const TTable *  pTable, const uint16_t  y, const uint16_t  x  )

inlinestatic

A 3D table with 6 x 6 dimensions, Rpm x-axis and Load y-axis.

A 3D table with 4 x 4 dimensions, Rpm x-axis and Load y-axis

A 3D table with 8 x 8 dimensions, Rpm x-axis and Load y-axis

A 3D table with 16 x 16 dimensions, Rpm x-axis and Load y-axis

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getConversionFactor()

static constexpr uint16_t getConversionFactor ( AxisDomain  domain )

staticconstexpr

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