func crop(mw *imagick.MagickWand, geo btcdn.GeoBox) (err error) {
offsetX, offsetY, err := calculateGravityOffsets(int(mw.GetImageWidth()), int(mw.GetImageHeight()), geo)
if err != nil {
return
}
err = mw.CropImage(uint(geo.Width()), uint(geo.Height()), offsetX, offsetY)
if err != nil {
return
}
return
}
func calculateGravityOffsets(baseWidth int, baseHeight int, geo btcdn.GeoBox) (offsetX int, offsetY int, err error) {
cropWidth := geo.Width()
cropHeight := geo.Height()
if cropWidth > baseWidth {
cropWidth = baseWidth
}
if cropHeight > cropHeight {
cropHeight = baseHeight
}
switch geo.Gravity() {
case "":
offsetX = geo.Offset()[0]
offsetY = geo.Offset()[1]
case "c":
offsetX = (baseWidth - cropWidth) / 2
offsetY = (baseHeight - cropHeight) / 2
case "n":
offsetX = (baseWidth - cropWidth) / 2
offsetY = 0
case "nw":
offsetX = 0
offsetY = 0
case "ne":
offsetX = baseWidth - cropWidth
offsetY = 0
case "s":
offsetX = (baseWidth - cropWidth) / 2
offsetY = baseHeight - cropHeight
case "sw":
offsetX = 0
offsetY = baseHeight - cropHeight
case "se":
offsetX = baseWidth - cropWidth
offsetY = baseHeight - cropHeight
case "w":
offsetX = 0
offsetY = (baseHeight - cropHeight) / 2
case "e":
offsetX = baseWidth - cropWidth
offsetY = (baseHeight - cropHeight) / 2
}
return
}
func (pr *BimgProcessor) Process(buffer []byte, geo btcdn.GeoBox) (img btcdn.Image, err error) {
bimgImg := bimg.NewImage(buffer)
var newImage []byte
gravity := resolveGravity(geo.Gravity())
if geo.Cropped() && geo.Resized() {
newImage, err = resizeAndCrop(bimgImg, geo.Width(), geo.Height(), gravity)
} else if geo.Resized() {
if geo.Mode() == "!" {
newImage, err = forceResize(bimgImg, geo.Width(), geo.Height())
} else {
newImage, err = resize(bimgImg, geo.Width())
}
} else if geo.Cropped() {
newImage, err = crop(bimgImg, int(float64(geo.Offset()[1])), int(float64(geo.Offset()[0])), geo.Width(), geo.Height())
}
if geo.Greyscale() {
newImage, err = bimgImg.Colourspace(bimg.INTERPRETATION_B_W)
}
img = &Image{
body: newImage,
mime: Mimes[bimgImg.Type()],
}
return
}
func resize(mw *imagick.MagickWand, geo btcdn.GeoBox) (err error) {
var height uint
width := geo.Width()
baseWidth := int(mw.GetImageWidth())
if width > baseWidth {
width = baseWidth
}
if geo.Mode() == "!" {
height = uint(geo.Height())
} else {
ratio := heightToWidthRatio(mw)
height = uint((float64)(width) * ratio)
}
err = mw.ResizeImage(uint(width), height, imagick.FILTER_LANCZOS, 1)
if err != nil {
return
}
return
}