Method applyTransformations

processor/vipsprocessor/process.go:591–793

applyTransformations applies all image transformations (crop, resize, flip, filters)

(
	ctx context.Context, img *vips.Image, p imagorpath.Params, load imagor.LoadFunc, thumbnail, stretch, upscale bool, focalRects []focal,
)

// applyTransformations applies all image transformations (crop, resize, flip, filters)
func (v *Processor) applyTransformations(
	ctx context.Context, img *vips.Image, p imagorpath.Params, load imagor.LoadFunc, thumbnail, stretch, upscale bool, focalRects []focal,
) error {
	var (
		origWidth  = float64(img.Width())
		origHeight = float64(img.PageHeight())
		cropLeft,
		cropTop,
		cropRight,
		cropBottom float64
	)
	if p.CropRight > 0 || p.CropLeft > 0 || p.CropBottom > 0 || p.CropTop > 0 {
		cropLeft = math.Max(p.CropLeft, 0)
		cropTop = math.Max(p.CropTop, 0)
		cropRight = p.CropRight
		cropBottom = p.CropBottom
		if p.CropLeft < 1 && p.CropTop < 1 && p.CropRight <= 1 && p.CropBottom <= 1 {
			cropLeft = math.Round(cropLeft * origWidth)
			cropTop = math.Round(cropTop * origHeight)
			cropRight = math.Round(cropRight * origWidth)
			cropBottom = math.Round(cropBottom * origHeight)
		}
		if cropRight == 0 {
			cropRight = origWidth - 1
		}
		if cropBottom == 0 {
			cropBottom = origHeight - 1
		}
		cropRight = math.Min(cropRight, origWidth-1)
		cropBottom = math.Min(cropBottom, origHeight-1)
	}
	if p.Trim {
		if l, t, w, h, err := findTrim(ctx, img, p.TrimBy, p.TrimTolerance); err == nil {
			cropLeft = math.Max(cropLeft, float64(l))
			cropTop = math.Max(cropTop, float64(t))
			if cropRight > 0 {
				cropRight = math.Min(cropRight, float64(l+w))
			} else {
				cropRight = float64(l + w)
			}
			if cropBottom > 0 {
				cropBottom = math.Min(cropBottom, float64(t+h))
			} else {
				cropBottom = float64(t + h)
			}
		}
	}
	if cropRight > cropLeft && cropBottom > cropTop {
		if err := img.ExtractAreaMultiPage(
			int(cropLeft), int(cropTop), int(cropRight-cropLeft), int(cropBottom-cropTop),
		); err != nil {
			return err
		}
	}
	var (
		w = p.Width
		h = p.Height
	)