Documentation
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Index ¶
- Constants
- func FromBitmap(bitmap Bitmap, palette color.Palette) image.PalettedImage
- func LoadPalette(reader io.Reader) (pal color.Palette, err error)
- func SavePalette(writer io.Writer, pal color.Palette) (err error)
- func Write(writer io.Writer, bmp Bitmap, bmpType BitmapType, forceTransparency bool, ...)
- type Bitmap
- type BitmapHeader
- type BitmapType
- type MemoryBitmap
Constants ¶
const ColorsPerPixel = 256
ColorsPerPixel is the constant 256, specifying how many colors are available for one pixel.
Variables ¶
This section is empty.
Functions ¶
func FromBitmap ¶
func FromBitmap(bitmap Bitmap, palette color.Palette) image.PalettedImage
FromBitmap returns a paletted image instance based on the provided bitmap. If the bitmap does not contain a private palette, the provided one is used.
func LoadPalette ¶
LoadPalette reads the raw serialized palette from the given reader and returns the extracted palette. The first color has an alpha value of 0x00.
func SavePalette ¶
SavePalette encodes the provided palette into the given writer. Alpha information is lost, the colors are converted to NRGBA and only their Red, Green and Blue values are used.
func Write ¶
func Write(writer io.Writer, bmp Bitmap, bmpType BitmapType, forceTransparency bool, startOffset int)
Write serializes given bitmap. The provided type specifies whether the pixel data shall be compressed. The start offset is used for images with a private palette. The start offset specifies the byte length of the blocks before the current one. Force transparency indicates that palette index 0x00 is meant to be treated as transparent. Some usages of bitmaps imply transparency and don't require this flag to be set.
Types ¶
type Bitmap ¶
type Bitmap interface {
// ImageWidth returns the width of the bitmap in pixel.
ImageWidth() uint16
// ImageHeight returns the height of the bitmap in pixel.
ImageHeight() uint16
// Row returns a slice of the pixel data for given row index.
Row(index int) []byte
// Palette returns the private palette of the bitmap. If none is set, this method returns nil.
Palette() color.Palette
// Hotspot returns a rectangle within the image bounds. May be 0,0,0,0.
Hotspot() image.Rectangle
}
Bitmap wraps the access to a bitmap into abstract functions.
func NullBitmap ¶ added in v1.0.0
func NullBitmap() Bitmap
NullBitmap returns a bitmap of zero size without a palette.
type BitmapHeader ¶
type BitmapHeader struct {
Unknown0000 [4]byte
Type BitmapType
TransparencyFlag int16
Width uint16
Height uint16
Stride uint16
WidthFactor byte
HeightFactor byte
HotspotBox [4]uint16
PaletteOffset int32
}
BitmapHeader describes the header of an encoded bitmap
func (*BitmapHeader) String ¶
func (header *BitmapHeader) String() (result string)
type BitmapType ¶
type BitmapType int16
const ( UncompressedBitmap BitmapType = 0x0002 CompressedBitmap BitmapType = 0x0004 )
func (BitmapType) String ¶
func (bmpType BitmapType) String() (result string)
type MemoryBitmap ¶
type MemoryBitmap struct {
// contains filtered or unexported fields
}
MemoryBitmap is a bitmap held in memory.
func NewMemoryBitmap ¶
func NewMemoryBitmap(header *BitmapHeader, data []byte, palette color.Palette) *MemoryBitmap
NewMemoryBitmap returns a MemoryBitmap instance based on the provided data.
func ToBitmap ¶
func ToBitmap(img image.PalettedImage, palette color.Palette) *MemoryBitmap
ToBitmap creates a MemoryBitmap out of a paletted image. If a palette is provided, this will be used as the private palette of the resulting bitmap.
func (*MemoryBitmap) Compressed ¶
func (bmp *MemoryBitmap) Compressed() bool
Compressed returns whether the bitmap data is stored in compressed form
func (*MemoryBitmap) Hotspot ¶
func (bmp *MemoryBitmap) Hotspot() image.Rectangle
Hotspot returns a rectangle within the image bounds. May be 0,0,0,0.
func (*MemoryBitmap) ImageHeight ¶
func (bmp *MemoryBitmap) ImageHeight() uint16
ImageHeight returns the height of the bitmap in pixel.
func (*MemoryBitmap) ImageWidth ¶
func (bmp *MemoryBitmap) ImageWidth() uint16
ImageWidth returns the width of the bitmap in pixel.
func (*MemoryBitmap) Palette ¶
func (bmp *MemoryBitmap) Palette() color.Palette
Palette returns the private palette of the bitmap. If none is set, this method returns nil.
func (*MemoryBitmap) Row ¶
func (bmp *MemoryBitmap) Row(index int) []byte
Row returns a slice of the pixel data for given row index.
Source Files