Function

CGFunctionCreate

Creates a Core Graphics function.

Declaration

CGFunctionRef CGFunctionCreate(void *info, size_t domainDimension, const CGFloat *domain, size_t rangeDimension, const CGFloat *range, const CGFunctionCallbacks *callbacks);

Parameters

info

A pointer to user-defined storage for data that you want to pass to your callbacks. You need to make sure that the data persists for as long as it’s needed, which can be beyond the scope in which the Core Graphics function is used.

domainDimension

The number of inputs.

domain

An array of (2*domainDimension) floats used to specify the valid intervals of input values. For each k from 0 to (domainDimension - 1), domain[2*k] must be less than or equal to domain[2*k+1], and the kth input value will be clipped to lie in the interval domain[2*k] ≤ input[k] ≤ domain[2*k+1]. If this parameter is NULL, then the input values are not clipped.

rangeDimension

The number of outputs.

range

An array of (2*rangeDimension) floats that specifies the valid intervals of output values. For each k from 0 to (rangeDimension - 1), range[2*k] must be less than or equal to range[2*k+1], and the kth output value will be clipped to lie in the interval range[2*k] ≤ output[k] ≤ range[2*k+1]. If this parameter is NULL, then the output values are not clipped.

callbacks

A pointer to a callback function table. This table should contain pointers to the callbacks you provide to implement the semantics of this Core Graphics function. Core Graphics makes a copy of your table, so, for example, you could safely pass in a pointer to a structure on the stack.

Return Value

The new Core Graphics function. You are responsible for releasing this object using CGFunctionRelease.