36 lines
826 B
Go
36 lines
826 B
Go
|
// Copyright 2011 The Graphics-Go Authors. All rights reserved.
|
||
|
|
// Use of this source code is governed by a BSD-style
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
package graphics
|
||
|
|
|
||
|
|
import (
|
||
|
|
"code.google.com/p/graphics-go/graphics/interp"
|
||
|
|
"errors"
|
||
|
|
"image"
|
||
|
|
"image/draw"
|
||
|
|
)
|
||
|
|
|
||
|
|
// RotateOptions are the rotation parameters.
|
||
|
|
// Angle is the angle, in radians, to rotate the image clockwise.
|
||
|
|
type RotateOptions struct {
|
||
|
|
Angle float64
|
||
|
|
}
|
||
|
|
|
||
|
|
// Rotate produces a rotated version of src, drawn onto dst.
|
||
|
|
func Rotate(dst draw.Image, src image.Image, opt *RotateOptions) error {
|
||
|
|
if dst == nil {
|
||
|
|
return errors.New("graphics: dst is nil")
|
||
|
|
}
|
||
|
|
if src == nil {
|
||
|
|
return errors.New("graphics: src is nil")
|
||
|
|
}
|
||
|
|
|
||
|
|
angle := 0.0
|
||
|
|
if opt != nil {
|
||
|
|
angle = opt.Angle
|
||
|
|
}
|
||
|
|
|
||
|
|
return I.Rotate(angle).TransformCenter(dst, src, interp.Bilinear)
|
||
|
|
}
|