// NewFromImage uses the given image as the destination for all calls to Add.
// It is assumed to be empty at the beginning so all the available space will be
// used for sub-images.
func NewFromImage(atlas draw.Image) *Atlas {
packer := binpacker.New(atlas.Bounds().Dx(), atlas.Bounds().Dy())
return &Atlas{
Image: atlas,
packer: packer,
}
}
func pack(paths []string) error {
packer := binpacker.New(*binSize, *binSize)
bin := image.NewRGBA(image.Rect(0, 0, *binSize, *binSize))
boundsTable := make(map[string]binpacker.Rect)
for _, path := range paths {
file, err := os.Open(path)
if err != nil {
return err
}
defer file.Close()
img, _, err := image.Decode(file)
if err != nil {
return err
}
rect, err := packer.Insert(img.Bounds().Dx(), img.Bounds().Dy())
if err != nil {
return err
}
draw.Draw(bin, bounds(rect), img, img.Bounds().Min, draw.Src)
boundsTable[id(path)] = rect
}
if err := saveTable(boundsTable, *tableFile); err != nil {
return err
}
return saveImage(bin, *outputImageFile)
}
// New creates a new square image atlas of the given size. The bounds will have
// (0,0) as the minimum and the image is of type NRGBA.
func New(size int) *Atlas {
packer := binpacker.New(size, size)
return &Atlas{
Image: image.NewNRGBA(image.Rect(0, 0, size, size)),
packer: packer,
}
}