pixie/README.md
2022-07-26 00:19:43 -05:00

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<img src="docs/banner.png">
👏 👏 👏 Check out video about the library: [A full-featured 2D graphics library for Nim (NimConf 2021)](https://www.youtube.com/watch?v=8acDfUIwLnk) 👏 👏 👏
# Pixie - A full-featured 2D graphics library for Nim
Pixie is a 2D graphics library similar to [Cairo](https://www.cairographics.org/) and [Skia](https://skia.org) written (almost) entirely in Nim.
This library is being actively developed and we'd be happy for you to use it.
`nimble install pixie`
![Github Actions](https://github.com/treeform/pixie/workflows/Github%20Actions/badge.svg)
[API reference](https://nimdocs.com/treeform/pixie)
Features:
* Typesetting and rasterizing text, including styled rich text via spans.
* Drawing paths, shapes and curves with even-odd and non-zero windings.
* Pixel-perfect AA quality.
* Supported file formats are 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.
* Many operations are SIMD accelerated.
### Image file formats
Format | Read | Write |
------------- | ------------- | ------------- |
PNG | ✅ | ✅ |
JPEG | ✅ | |
BMP | ✅ | ✅ |
QOI | ✅ | ✅ |
GIF | ✅ | |
SVG | ✅ | |
PPM | ✅ | ✅ |
### Font file formats
Format | Read
------------- | -------------
TTF | ✅
OTF | ✅
SVG | ✅
### Joins and caps
Supported Caps:
* Butt
* Round
* Square
Supported Joins:
* Miter (with miter angle limit)
* 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 | ✅ | cubic curve to |
Q q T t | ✅ | quadratic curve to |
A a | ✅ | arc to |
z | ✅ | close path |
### Pixie + GPU
To learn how to use Pixie for realtime graphics with GPU, check out [Boxy](https://github.com/treeform/boxy).
## Testing
`nimble test`
## Examples
`git clone https://github.com/treeform/pixie` to run examples.
### Text
nim c -r [examples/text.nim](examples/text.nim)
```nim
var font = readFont("examples/data/Roboto-Regular_1.ttf")
font.size = 20
let text = "Typesetting is the arrangement and composition of text in graphic design and publishing in both digital and traditional medias."
image.fillText(font.typeset(text, vec2(180, 180)), translate(vec2(10, 10)))
```
![example output](examples/text.png)
### Text spans
nim c -r [examples/text_spans.nim](examples/text_spans.nim)
```nim
let typeface = readTypeface("examples/data/Ubuntu-Regular_1.ttf")
proc newFont(typeface: Typeface, size: float32, color: Color): Font =
result = newFont(typeface)
result.size = size
result.paint.color = color
let spans = @[
newSpan("verb [with object] ",
newFont(typeface, 12, color(0.78125, 0.78125, 0.78125, 1))),
newSpan("strallow\n", newFont(typeface, 36, color(0, 0, 0, 1))),
newSpan("\nstral·low\n", newFont(typeface, 13, color(0, 0.5, 0.953125, 1))),
newSpan("\n1. free (something) from restrictive restrictions \"the regulations are intended to strallow changes in public policy\" ",
newFont(typeface, 14, color(0.3125, 0.3125, 0.3125, 1)))
]
image.fillText(typeset(spans, vec2(180, 180)), translate(vec2(10, 10)))
```
![example output](examples/text_spans.png)
### Square
nim c -r [examples/square.nim](examples/square.nim)
```nim
let ctx = newContext(image)
ctx.fillStyle = rgba(255, 0, 0, 255)
let
pos = vec2(50, 50)
wh = vec2(100, 100)
ctx.fillRect(rect(pos, wh))
```
![example output](examples/square.png)
### Line
nim c -r [examples/line.nim](examples/line.nim)
```nim
let ctx = newContext(image)
ctx.strokeStyle = "#FF5C00"
ctx.lineWidth = 10
let
start = vec2(25, 25)
stop = vec2(175, 175)
ctx.strokeSegment(segment(start, stop))
```
![example output](examples/line.png)
### Rounded rectangle
nim c -r [examples/rounded_rectangle.nim](examples/rounded_rectangle.nim)
```nim
let ctx = newContext(image)
ctx.fillStyle = rgba(0, 255, 0, 255)
let
pos = vec2(50, 50)
wh = vec2(100, 100)
r = 25.0
ctx.fillRoundedRect(rect(pos, wh), r)
```
![example output](examples/rounded_rectangle.png)
### Heart
nim c -r [examples/heart.nim](examples/heart.nim)
```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](examples/heart.png)
### Masking
nim c -r [examples/masking.nim](examples/masking.nim)
```nim
let ctx = newContext(lines)
ctx.strokeStyle = "#F8D1DD"
ctx.lineWidth = 30
ctx.strokeSegment(segment(vec2(25, 25), vec2(175, 175)))
ctx.strokeSegment(segment(vec2(25, 175), vec2(175, 25)))
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
""",
color(1, 1, 1, 1)
)
lines.draw(mask, blendMode = MaskBlend)
image.draw(lines)
```
![example output](examples/masking.png)
### Gradient
nim c -r [examples/gradient.nim](examples/gradient.nim)
```nim
let paint = newPaint(RadialGradientPaint)
paint.gradientHandlePositions = @[
vec2(100, 100),
vec2(200, 100),
vec2(100, 200)
]
paint.gradientStops = @[
ColorStop(color: color(1, 0, 0, 1), position: 0),
ColorStop(color: color(1, 0, 0, 0.15625), position: 1.0),
]
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
""",
paint
)
```
![example output](examples/gradient.png)
### Image tiled
nim c -r [examples/image_tiled.nim](examples/image_tiled.nim)
```nim
let path = newPath()
path.polygon(
vec2(100, 100),
70,
sides = 8
)
let paint = newPaint(TiledImagePaint)
paint.image = readImage("examples/data/mandrill.png")
paint.imageMat = scale(vec2(0.08, 0.08))
image.fillPath(path, paint)
```
![example output](examples/image_tiled.png)
### Shadow
nim c -r [examples/shadow.nim](examples/shadow.nim)
```nim
let path = newPath()
path.polygon(vec2(100, 100), 70, sides = 8)
let polygonImage = newImage(200, 200)
polygonImage.fillPath(path, 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](examples/shadow.png)
### Blur
nim c -r [examples/blur.nim](examples/blur.nim)
```nim
let path = newPath()
path.polygon(vec2(100, 100), 70, sides = 6)
let mask = newImage(200, 200)
mask.fillPath(path, color(1, 1, 1, 1))
blur.blur(20)
blur.draw(mask, blendMode = MaskBlend)
image.draw(trees)
image.draw(blur)
```
![example output](examples/blur.png)
### Tiger
nim c -r [examples/tiger.nim](examples/tiger.nim)
```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](examples/tiger.png)