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mirror of https://github.com/exyte/Macaw.git synced 2024-11-11 01:42:35 +03:00
Macaw/Source/svg/SVGSerializer.swift
2018-04-19 16:37:25 +07:00

389 lines
14 KiB
Swift

//
// SVGSerializer.swift
// Macaw
//
// Created by Yuriy Kashnikov on 8/17/17.
// Copyright © 2017 Exyte. All rights reserved.
//
import Foundation
///
/// This class serializes Macaw Scene into an SVG String
///
open class SVGSerializer {
fileprivate let width: Int?
fileprivate let height: Int?
fileprivate let id: String?
fileprivate let indent: Int
fileprivate init(width: Int?, height: Int?, id: String?) {
self.width = width
self.height = height
self.id = id
self.indent = 0
}
// header and footer
fileprivate let SVGDefaultHeader = "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" version=\"1.1\""
fileprivate static let SVGDefaultId = ""
fileprivate static let SVGUndefinedSize = -1
fileprivate let SVGFooter = "</svg>"
// groups
fileprivate let SVGGroupOpenTag = "<g"
fileprivate let SVGGroupCloseTag = "</g>"
// shapes
fileprivate let SVGRectOpenTag = "<rect "
fileprivate let SVGCircleOpenTag = "<circle "
fileprivate let SVGEllipseOpenTag = "<ellipse "
fileprivate let SVGLineOpenTag = "<line "
fileprivate let SVGPolylineOpenTag = "<polyline "
fileprivate let SVGPolygonOpenTag = "<polygon "
fileprivate let SVGPathOpenTag = "<path "
fileprivate let SVGImageOpenTag = "<image "
fileprivate let SVGTextOpenTag = "<text "
fileprivate let SVGGenericEndTag = ">"
fileprivate let SVGGenericCloseTag = "/>"
fileprivate let SVGUndefinedTag = "<UNDEFINED "
fileprivate let indentPrefixSymbol = " "
fileprivate let SVGClipPathName = "clipPath"
fileprivate let SVGEpsilon: Double = 0.00001
fileprivate let SVGDefaultOpacityValueAsAlpha = 1 * 255
fileprivate func indentTextWithOffset(_ text: String, _ offset: Int) -> String {
if self.indent != 0 {
let prefix = String(repeating: indentPrefixSymbol, count: self.indent)
return "\n\(String(repeating: prefix, count: offset))\(text)"
}
return text
}
fileprivate func att(_ a: Double) -> String {
return String(Int(a))
}
fileprivate func tag(_ tag: String, _ args: [String: String]=[:], close: Bool = false) -> String {
let attrs = args.map { "\($0)=\"\($1)\"" }.joined(separator: " ")
let closeTag = close ? " />" : ""
return "\(tag) \(attrs) \(closeTag)"
}
fileprivate func arcToSVG(_ arc: Arc) -> String {
if arc.shift == 0.0 && abs(arc.extent - .pi * 2.0) < SVGEpsilon {
return tag(SVGEllipseOpenTag, ["cx": att(arc.ellipse.cx), "cy": att(arc.ellipse.cy), "rx": att(arc.ellipse.rx), "ry": att(arc.ellipse.ry)])
} else {
let rx = arc.ellipse.rx
let ry = arc.ellipse.ry
let cx = arc.ellipse.cx
let cy = arc.ellipse.cy
let theta1 = arc.shift
let delta = arc.extent
let theta2 = theta1 + delta
let x1 = cx + rx * cos(theta1)
let y1 = cy + ry * sin(theta1)
let x2 = cx + rx * cos(theta2)
let y2 = cy + ry * sin(theta2)
let largeArcFlag = abs(delta) > .pi ? 1 : 0
let sweepFlag = delta > 0.0 ? 1 : 0
var d = "M\(x1),\(y1) "
d += "A \(rx),\(ry) 0.0 \(largeArcFlag), \(sweepFlag) \(x2),\(y2)"
return tag(SVGPathOpenTag, ["d": d])
}
}
fileprivate func polygonToSVG(_ polygon: Polygon) -> String {
let points = polygon.points.flatMap { String($0) }.joined(separator: ",")
return tag(SVGPolygonOpenTag, ["points": points])
}
fileprivate func polylineToSVG(_ polyline: Polyline) -> String {
let points = polyline.points.flatMap { String($0) }.joined(separator: ",")
return tag(SVGPolylineOpenTag, ["points": points])
}
fileprivate func pathToSVG(_ path: Path) -> String {
var d = ""
for segment in path.segments {
d += "\(segment.type) \(segment.data.flatMap { String(Int($0)) }.joined(separator: " "))"
}
return tag(SVGPathOpenTag, ["d": d])
}
fileprivate func lineToSVG(_ line: Line) -> String {
return tag(SVGLineOpenTag, ["x1": String(Int(line.x1)), "y1": att(line.y1), "x2": att(line.x2), "y2": att(line.y2)])
}
fileprivate func ellipseToSVG(_ ellipse: Ellipse) -> String {
return tag(SVGEllipseOpenTag, ["cx": att(ellipse.cx), "cy": att(ellipse.cy), "rx": att(ellipse.rx), "ry": att(ellipse.ry)])
}
fileprivate func circleToSVG(_ circle: Circle) -> String {
return tag(SVGCircleOpenTag, ["cx": att(circle.cx), "cy": att(circle.cy), "r": att(circle.r)])
}
fileprivate func roundRectToSVG(_ roundRect: RoundRect) -> String {
return tag(SVGRectOpenTag, ["rx": att(roundRect.rx), "ry": att(roundRect.ry), "width": att(roundRect.rect.w), "height": att(roundRect.rect.h)])
}
fileprivate func rectToSVG(_ rect: Rect) -> String {
return tag(SVGRectOpenTag, ["x": att(rect.x), "y": att(rect.y), "width": att(rect.w), "height": att(rect.h)])
}
fileprivate func imageToSVG(_ image: Image) -> String {
var result = tag(SVGImageOpenTag, close: false)
result += clipToSVG(image.clip)
result += transformToSVG(image)
if image.src.contains("memory://") {
if let data = image.base64encoded(type: Image.ImageRepresentationType.PNG) {
result += " xlink:href=\"data:image/png;base64,\(data)\""
}
} else {
result += " xlink:href=\"\(image.src)\" "
}
if let bounds = image.bounds() {
result += " width=\"\(String(bounds.w))\" height=\"\(String(bounds.h))\" "
}
result += SVGGenericCloseTag
return result
}
fileprivate func alignToSVG(_ align: Align) -> String {
if align === Align.mid {
return " text-anchor=\"middle\" "
}
if align === Align.max {
return " text-anchor=\"end "
}
return ""
}
fileprivate func baselineToSVG(_ baseline: Baseline) -> String {
if baseline == .top {
return " dominant-baseline=\"text-before-edge\" "
}
return ""
}
fileprivate func textToSVG(_ text: Text) -> String {
var result = tag(SVGTextOpenTag)
if let font = text.font {
result += " font-family=\"\(font.name)\" font-size=\"\(font.size)\" "
// TODO: check with enums
if font.name != "normal" {
result += " font-weight=\"\(font.weight)\" "
}
}
result += alignToSVG(text.align)
result += baselineToSVG(text.baseline)
result += clipToSVG(text.clip)
result += fillToSVG(text.fillVar.value)
result += strokeToSVG(text.strokeVar.value)
result += transformToSVG(text)
result += SVGGenericEndTag
result += text.text
result += "</text>"
return result
}
fileprivate func colorToSVG(_ color: Color) -> String {
if let c = SVGConstants.valueToColor(color.val) {
return "\(c)"
} else {
let r = color.r()
let g = color.g()
let b = color.b()
return "#\(String(format: "%02X%02X%02X", r, g, b))"
}
}
fileprivate func fillToSVG(_ fill: Fill?) -> String {
if let fillColor = fill as? Color {
var result = " fill=\"\(colorToSVG(fillColor))\""
if let opacity = alphaToSVGOpacity(fillColor.a()) {
result += " fill-opacity=\"\(opacity)\""
}
return result
}
return " fill=\"none\""
}
fileprivate func alphaToSVGOpacity(_ alpha: Int) -> String? {
if alpha == SVGDefaultOpacityValueAsAlpha {
return .none
}
return String(Double(alpha) / Double(SVGDefaultOpacityValueAsAlpha))
}
fileprivate func strokeToSVG(_ stroke: Stroke?) -> String {
var result = ""
if let strokeColor = stroke?.fill as? Color {
result += " stroke=\"\(colorToSVG(strokeColor))\""
if let opacity = alphaToSVGOpacity(strokeColor.a()) {
result += " stroke-opacity=\"\(opacity)\""
}
}
if let strokeWidth = stroke?.width {
result += " stroke-width=\"\(strokeWidth)\""
}
if let strokeCap = stroke?.cap {
if strokeCap != SVGConstants.defaultStrokeLineCap {
result += " stroke-linecap=\"\(strokeCap)\""
}
}
if let strokeJoin = stroke?.join {
if strokeJoin != SVGConstants.defaultStrokeLineJoin {
result += " stroke-linejoin=\"\(strokeJoin)\""
}
}
if let strokeDashes = stroke?.dashes, strokeDashes.count > 0 {
let dashes = strokeDashes.map{ String($0) }.joined(separator: ",")
result += " stroke-dasharray=\"\(dashes)\""
}
if let strokeOffset = stroke?.offset {
if strokeOffset != 0 {
result += " stroke-dashoffset=\"\(strokeOffset)\""
}
}
return result
}
fileprivate func isSignificantMatrixTransform(_ t: Transform) -> Bool {
for k in [t.m11, t.m12, t.m21, t.m22, t.dx, t.dy] {
if abs(k) > SVGEpsilon {
return true
}
}
return false
}
fileprivate func transformToSVG(_ shape: Node) -> String {
if [shape.place.m11, shape.place.m12, shape.place.m21, shape.place.m22] == [1.0, 0.0, 0.0, 1.0] {
if ([shape.place.dx, shape.place.dy] == [0.0, 0.0]) {
return ""
}
return " transform=\"translate(\(Int(shape.place.dx)),\(Int(shape.place.dy)))\" "
}
let matrixArgs = [shape.place.m11, shape.place.m12, shape.place.m21, shape.place.m22, shape.place.dx, shape.place.dy].map { String($0) }.joined(separator: ",")
return " transform=\"matrix(\(matrixArgs))\" "
}
fileprivate func locusToSVG(_ locus: Locus) -> String {
switch locus {
case let arc as Arc:
return arcToSVG(arc)
case let polygon as Polygon:
return polygonToSVG(polygon)
case let polyline as Polyline:
return polylineToSVG(polyline)
case let path as Path:
return pathToSVG(path)
case let line as Line:
return lineToSVG(line)
case let ellipse as Ellipse:
return ellipseToSVG(ellipse)
case let circle as Circle:
return circleToSVG(circle)
case let roundRect as RoundRect:
return roundRectToSVG(roundRect)
case let rect as Rect:
return rectToSVG(rect)
default:
return "\(SVGUndefinedTag) locus:\(locus)"
}
}
fileprivate var defs: String = ""
fileprivate func getDefs() -> String {
if defs.isEmpty {
return ""
}
return "<defs>" + defs + "</defs>"
}
fileprivate var clipPathCount: Int = 0
fileprivate func addClipToDefs(_ clip: Locus) {
clipPathCount += 1
defs += "<clipPath id=\"\(SVGClipPathName)\(clipPathCount)\">" + locusToSVG(clip) + SVGGenericCloseTag + "</clipPath>"
}
fileprivate func clipToSVG(_ clipLocus: Locus?) -> String {
guard let clip = clipLocus else {
return ""
}
addClipToDefs(clip)
return " clip-path=\"url(#\(SVGClipPathName)\(clipPathCount))\" "
}
fileprivate func macawShapeToSvgShape (macawShape: Shape) -> String {
let locus = macawShape.formVar.value
var result = locusToSVG(locus)
result += clipToSVG(macawShape.clip)
result += fillToSVG(macawShape.fillVar.value)
result += strokeToSVG(macawShape.strokeVar.value)
result += transformToSVG(macawShape)
result += SVGGenericCloseTag
return result
}
fileprivate func serialize(node: Node, offset: Int) -> String {
if let shape = node as? Shape {
return indentTextWithOffset(macawShapeToSvgShape(macawShape: shape), offset)
}
if let group = node as? Group {
var result = indentTextWithOffset(SVGGroupOpenTag, offset)
result += clipToSVG(group.clip)
result += transformToSVG(group)
result += SVGGenericEndTag
for child in group.contentsVar.value {
result += serialize(node: child, offset: offset + 1)
}
result += indentTextWithOffset(SVGGroupCloseTag, offset)
return result
}
if let image = node as? Image {
return imageToSVG(image)
}
if let text = node as? Text {
return textToSVG(text)
}
return "SVGUndefinedTag \(node)"
}
fileprivate func serialize(node: Node) -> String {
var optionalSection = ""
if let w = width {
optionalSection += "width=\"\(w)\""
}
if let h = height {
optionalSection += " height=\"\(h)\""
}
if let i = id {
optionalSection += " id=\"\(i)\""
}
var result = [SVGDefaultHeader, optionalSection, SVGGenericEndTag].joined(separator: " ")
let body = serialize(node: node, offset: 1)
result += getDefs() + body
result += indentTextWithOffset(SVGFooter, 0)
return result
}
open class func serialize(node: Node, width: Int? = nil, height: Int? = nil, id: String? = nil) -> String {
return SVGSerializer(width: width, height: height, id: id).serialize(node: node)
}
}