translate and expand

Author: swhitty

SwiftDraw/CommandLine+Process.swift

@@ -95,14 +95,17 @@ public extension CommandLine {
         #if canImport(CoreGraphics)
         switch config.format {
         case .jpeg:
-            let insets = try makeImageInsets(for: config.insets)
-            return try image.jpegData(size: config.size.cgValue, scale: config.scale.cgValue, insets: insets)
+            return try image
+                .inset(makeImageInsets(for: config.insets))
+                .jpegData(size: config.size.cgValue, scale: config.scale.cgValue)
         case .pdf:
-            let insets = try makeImageInsets(for: config.insets)
-            return try image.pdfData(size: config.size.cgValue, insets: insets)
+            return try image
+                .inset(makeImageInsets(for: config.insets))
+                .pdfData(size: config.size.cgValue)
         case .png:
-            let insets = try makeImageInsets(for: config.insets)
-            return try image.pngData(size: config.size.cgValue, scale: config.scale.cgValue, insets: insets)
+            return try image
+                .inset(makeImageInsets(for: config.insets))
+                .pngData(size: config.size.cgValue, scale: config.scale.cgValue)
         case .swift, .sfsymbol:
             throw Error.unsupported
         }
@@ -129,6 +132,12 @@ public extension CommandLine {
     }
 }
 
+private extension SVG {
+    func inset(_ insets: Insets) -> SVG {
+        expand(top: -insets.top, left: -insets.left, bottom: -insets.bottom, right: -insets.right)
+    }
+}
+
 #if canImport(CoreGraphics)
 private extension CommandLine.Scale {
     var cgValue: CGFloat {

SwiftDraw/SVG+CoreGraphics.swift

@@ -38,23 +38,17 @@ public extension CGContext {
     func draw(_ image: SVG, in rect: CGRect? = nil)  {
         let defaultRect = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)
         let renderer = CGRenderer(context: self)
+        saveGState()
 
-        guard let rect = rect, rect != defaultRect else {
-            renderer.perform(image.commands)
-            return
+        if let rect = rect, rect != defaultRect {
+            translateBy(x: rect.origin.x, y: rect.origin.y)
+            scaleBy(
+                x: rect.width / image.size.width,
+                y: rect.height / image.size.height
+            )
         }
+        renderer.perform(image.commands)
 
-        let scale = CGSize(width: rect.width / image.size.width,
-                           height: rect.height / image.size.height)
-        draw(image.commands, in: rect, scale: scale)
-    }
-
-    fileprivate func draw(_ commands: [RendererCommand<CGTypes>], in rect: CGRect, scale: CGSize = CGSize(width: 1.0, height: 1.0)) {
-        let renderer = CGRenderer(context: self)
-        saveGState()
-        translateBy(x: rect.origin.x, y: rect.origin.y)
-        scaleBy(x: scale.width, y: scale.height)
-        renderer.perform(commands)
         restoreGState()
     }
 }

SwiftDraw/SVG.swift

@@ -94,6 +94,23 @@ extension SVG {
         )
         return copy
     }
+
+    public func translate(tx: CGFloat, ty: CGFloat) -> SVG {
+        var copy = self
+        copy.commands.insert(.translate(tx: tx, ty: ty), at: 0)
+        return copy
+    }
+
+    public func expand(top: CGFloat = 0,
+                       left: CGFloat = 0,
+                       bottom: CGFloat = 0,
+                       right: CGFloat = 0) -> SVG {
+        var copy = self
+        copy.commands.insert(.translate(tx: left, ty: top), at: 0)
+        copy.size.width += left + right
+        copy.size.height += top + bottom
+        return copy
+    }
 }
 
 extension SVG {
@@ -105,6 +122,17 @@ extension SVG {
     public mutating func scaled(x: CGFloat, y: CGFloat) {
         self = scale(x: x, y: y)
     }
+
+    public mutating func translated(tx: CGFloat, ty: CGFloat) {
+        self = translate(tx: tx, ty: ty)
+    }
+
+    public mutating func expanded(top: CGFloat = 0,
+                                  left: CGFloat = 0,
+                                  bottom: CGFloat = 0,
+                                  right: CGFloat = 0) {
+        self = expand(top: top, left: left, bottom: bottom, right: right)
+    }
 }
 
 extension SVG {

SwiftDrawTests/SVGTests.swift

@@ -98,6 +98,28 @@ final class SVGTests: XCTestCase {
         copy.scaled(5)
         XCTAssertEqual(copy.size, CGSize(width: 500, height: 500))
     }
+
+    func testTranslate() {
+        let image = SVG.makeLines()
+
+        XCTAssertEqual(image.size, CGSize(width: 100, height: 100))
+        XCTAssertEqual(image.translate(tx: 10, ty: 10).size, CGSize(width: 100, height: 100))
+
+        var copy = image
+        copy.translated(tx: 50, ty: 50)
+        XCTAssertEqual(copy.size, CGSize(width: 100, height: 100))
+    }
+
+    func testExpand() {
+        let image = SVG.makeLines()
+
+        XCTAssertEqual(image.size, CGSize(width: 100, height: 100))
+        XCTAssertEqual(image.expand(top: 50, right: 30).size, CGSize(width: 130, height: 150))
+
+        var copy = image
+        copy.expanded(left: -50, bottom: 30)
+        XCTAssertEqual(copy.size, CGSize(width: 50, height: 130))
+    }
 }
 
 private extension SVG {