canvas

Documentation

Overview

Package canvas represents a rectangular grid of Pixels.

Index

• Constants
• type Canvas
  • func NewCanvas(width, height int) *Canvas
  • func (c *Canvas) PixelAt(x, y int) (color.Color, error)
  • func (c *Canvas) ToPPM(writer io.Writer, goTemplate string) error
  • func (c *Canvas) ValidateInCanvasBounds(x, y int) error
  • func (c *Canvas) WritePixel(x, y int, color color.Color) error

Constants

const PixelMapTemplate = `{{ .PPMIdentifier }}
{{ .Width }} {{ .Height }}
{{ .MaxColorValue }}
{{ pixels .Pixels }}`

PixelMapTemplate is a template used for rendering a Canvas to a portable pixmap (PPM) file.

Types

type Canvas

type Canvas struct {
	Width         int
	Height        int
	Pixels        [][]color.Color
	PPMIdentifier string
	MaxColorValue uint8
	MinColorValue uint8
}

Canvas represents a rectangular grid of Pixels.

func NewCanvas

func NewCanvas(width, height int) *Canvas

NewCanvas returns a new Canvas with the passed Width and Height.

func (*Canvas) PixelAt

func (c *Canvas) PixelAt(x, y int) (color.Color, error)

PixelAt returns the Color at the pixel located at the passed x and y values.

func (*Canvas) ToPPM

func (c *Canvas) ToPPM(writer io.Writer, goTemplate string) error

ToPPM writes the current canvas to a file in the portable pixmap (PPM) format.

func (*Canvas) ValidateInCanvasBounds

func (c *Canvas) ValidateInCanvasBounds(x, y int) error

ValidateInCanvasBounds validates that the passed x and y values fit into the pixel bounds of the canvas.

func (*Canvas) WritePixel

func (c *Canvas) WritePixel(x, y int, color color.Color) error

WritePixel writes the passed Color to the Canvas at the pixel located at the passed x and y values.