Package: cairo

Function cairo:pattern-create-linear

Lambda List

cairo:pattern-create-linear (x0 y0 x1 y1)

Arguments

x0 -- a number for the x coordinate of the start point
y0 -- a number for the y coordinate of the start point
x1 -- a number for the x coordinate of the end point
y1 -- a number for the y coordinate of the end point

Return Value

The newly created cairo:pattern-t instance if successful, or an error pattern in case of no memory. The caller owns the returned instance and should call the cairo:pattern-destroy function when finished with it.

Details

Create a new linear gradient cairo:pattern-t instance along the line defined by (x0,y0) and (x1,y1). This function will always return a valid patttern, but if an error occurred the pattern status will be set to an error. To inspect the status of a pattern use the cairo:pattern-status function.

Before using the gradient pattern, a number of color stops should be defined using the cairo:pattern-add-color-stop-rgb or cairo:pattern-add-color-stop-rgba functions.

Notes

The coordinates here are in pattern space. For a new pattern, pattern space is identical to user space, but the relationship between the spaces can be changed with the cairo:pattern-matrix function.

Lisp implementation

The arguments are coerced to double floats before being passed to the foreign C function.
 

See also

2025-1-19