hdrimage

Documentation

Overview

Package hdrimage provides a float32 image implementation with a built-in divisor (for easy averaging of images), which conforms to Go's image.Image interface (by conversion to sRGB)

Index

• type Image
  • func Add(a *Image, b *Image) *Image
  • func Decode(reader io.Reader) (*Image, error)
  • func FromSRGB(im image.Image) *Image
  • func New(width, height int) *Image
  • func (im *Image) Add(other *Image)
  • func (im *Image) At(x, y int) color.Color
  • func (im *Image) AtHDR(x, y int) *hdrcolour.Colour
  • func (im *Image) Bounds() image.Rectangle
  • func (im *Image) ColorModel() color.Model
  • func (im *Image) Encode(writer io.Writer) error
  • func (im *Image) String() string

Examples

• Image.Add
• Image.At
• Image.Bounds
• Image.ColorModel
• Image.String

Types

type Image

type Image struct {
	Pixels        [][]hdrcolour.Colour
	Width, Height int
	Divisor       int
}

Image is a stuct which will display images via its 2D colour array, wich represents the screen

func Add

func Add(a *Image, b *Image) *Image

Add returns a new image which is the sum of the given ones

func Decode

func Decode(reader io.Reader) (*Image, error)

Decode reads data in the simple traytor_hdr format and produces an image.

func FromSRGB

func FromSRGB(im image.Image) *Image

FromSRGB constructs an Image from an sRGB image

func New

func New(width, height int) *Image

New will set the screen to the given width and height

func (*Image) Add

func (im *Image) Add(other *Image)

Add adds another image to this one

Example

im1 := New(2, 2)
for j := 0; j < im1.Height; j++ {
	for i := 0; i < im1.Width; i++ {
		im1.Pixels[i][j].SetColour(4, 5, 6)
	}
}
im2 := New(2, 2)
for j := 0; j < im2.Height; j++ {
	for i := 0; i < im2.Width; i++ {
		im2.Pixels[i][j].SetColour(1, 2, 3)
	}
}
im1.Add(im2)
fmt.Printf("%s\n", im1)

Output:

{5, 7, 9}, {5, 7, 9}
{5, 7, 9}, {5, 7, 9}

func (*Image) At

func (im *Image) At(x, y int) color.Color

At returns the sRGB Colour of the pixel at [x][y (scaled by the divisor)]

Example

im := New(2, 2)
for j := 0; j < im.Height; j++ {
	for i := 0; i < im.Width; i++ {
		im.Pixels[i][j].SetColour(float32(i), float32(j), 0)
	}
}
fmt.Printf("%s\n", im.At(0, 0))
fmt.Printf("%s\n", im.At(1, 0))
fmt.Printf("%s\n", im.At(0, 1))
fmt.Printf("%s\n", im.At(1, 1))

Output:

[0, 0, 0]
[65535, 0, 0]
[0, 65535, 0]
[65535, 65535, 0]

func (*Image) AtHDR

func (im *Image) AtHDR(x, y int) *hdrcolour.Colour

AtHDR returns the Colour of the pixel at [x][y] (scaled by the divisor)

func (*Image) Bounds

func (im *Image) Bounds() image.Rectangle

Bounds returns a rectangle as big as the image

Example

im := New(640, 480)

bounds := im.Bounds()
fmt.Printf("%s\n", bounds)

Output:

(0,0)-(640,480)

func (*Image) ColorModel

func (im *Image) ColorModel() color.Model

ColorModel returns the image's color model (as used by Go's image interface)

Example

im := New(640, 480)
if im.ColorModel() == color.RGBAModel {
	fmt.Printf("Model is RGBA\n")
}

Output:

Model is RGBA

func (*Image) Encode

func (im *Image) Encode(writer io.Writer) error

Encode writes data in the simple traytor_hdr format into a writer

func (*Image) String

func (im *Image) String() string

String returns a string which is the representaton of image: {r, g, b}, ... {r, g, b}\n ...\n {r, g, b},...{r, g, b}

Example

i := New(2, 2)
fmt.Printf("%s\n", i)

Output:

{0, 0, 0}, {0, 0, 0}
{0, 0, 0}, {0, 0, 0}