pixie/README.md
2021-02-25 08:51:09 -08:00

4.6 KiB

Pixie - A full-featured 2D graphics library for Nim

⚠️ WARNING: This library is still in heavy development. ⚠️

Pixie is a 2D graphics library similar to Cairo and Skia written (almost) entirely in Nim.

This library is being actively developed and is not yet ready for use. Since you've managed to stumble onto it, give it a star and check back soon!

nimble install pixie

Features:

  • Drawing paths, shapes and curves, with even-odd and non-zero windings.
  • Pixel perfect AA quality.
  • Supported file formats: PNG, BMP, JPG, SVG + more in development.
  • Strokes with joins and caps.
  • Shadows, glows and blurs.
  • Complex masking: Subtract, Intersect, Exclude.
  • Complex blends: Darken, Multiply, Color Dodge, Hue, Luminosity... etc.

API reference: https://treeform.github.io/pixie/pixie.html

File formats

Format Read Write
PNG
JPEG
BMP
SVG

Joins and caps:

Supported Saps:

  • Butt
  • Round
  • Square

Supported Joints:

  • Miter (with miter limit angle)
  • Bevel
  • Round

Blending & Masking.

Supported Blend Modes:

  • Normal
  • Darken
  • Multiply
  • ColorBurn
  • Lighten
  • Screen
  • Color Dodge
  • Overlay
  • Soft Light
  • Hard Light
  • Difference
  • Exclusion
  • Hue
  • Saturation
  • Color
  • Luminosity

Supported Mask Modes:

  • Mask
  • Overwrite
  • Subtract Mask
  • Intersect Mask
  • Exclude Mask

SVG style paths:

Format Supported Description
M,m move to
L,l line to
h,h horizontal line to
V,v vertical line to
C,c,S,s cublic to
Q,q,T,t quadratic to
A,a arc to
z close path

Testing

nimble test

Examples

Square

examples/square.nim

let
  pos = vec2(50, 50)
  wh = vec2(100, 100)

image.fillRect(rect(pos, wh), rgba(255, 0, 0, 255))

example output

Line

examples/line.nim

let
  start = vec2(25, 25)
  stop = vec2(175, 175)
  color = parseHtmlColor("#FF5C00").rgba

image.strokeSegment(segment(start, stop), color, strokeWidth = 10)

example output

Rounded rectangle

examples/rounded_rectangle.nim

let
  pos = vec2(50, 50)
  wh = vec2(100, 100)
  r = 25.0

image.fillRoundedRect(rect(pos, wh), r, rgba(0, 255, 0, 255))

example output

Heart

examples/heart.nim

image.fillPath(
  """
    M 20 60
    A 40 40 90 0 1 100 60
    A 40 40 90 0 1 180 60
    Q 180 120 100 180
    Q 20 120 20 60
    z
  """,
  parseHtmlColor("#FC427B").rgba
)

example output

Masking

examples/masking.nim

lines.strokeSegment(
  segment(vec2(25, 25), vec2(175, 175)), color, strokeWidth = 30)
lines.strokeSegment(
  segment(vec2(25, 175), vec2(175, 25)), color, strokeWidth = 30)

mask.fillPath(
  """
    M 20 60
    A 40 40 90 0 1 100 60
    A 40 40 90 0 1 180 60
    Q 180 120 100 180
    Q 20 120 20 60
    z
  """
)
lines.draw(mask)
image.draw(lines)

example output

Shadow

examples/shadow.nim

let polygonImage = newImage(200, 200)
polygonImage.fillPolygon(
  vec2(100, 100),
  70,
  sides = 8,
  rgba(255, 255, 255, 255)
)

let shadow = polygonImage.shadow(
  offset = vec2(2, 2),
  spread = 2,
  blur = 10,
  color = rgba(0, 0, 0, 200)
)

image.draw(shadow)
image.draw(polygonImage)

example output

Blur

examples/blur.nim

let mask = newMask(200, 200)
mask.fillPolygon(vec2(100, 100), 70, sides = 6)

blur.blur(20)
blur.draw(mask, blendMode = bmMask)

image.draw(trees)
image.draw(blur)

example output

Tiger

examples/tiger.nim

let tiger = readImage("examples/data/tiger.svg")

image.draw(
  tiger,
  translate(vec2(100, 100)) *
  scale(vec2(0.2, 0.2)) *
  translate(vec2(-450, -450))
)

example output