example-vector.md

Vector Drawing

PDFBlocks has a built-in Line component and shapes for Rectangle, Ellipse, Circle, Square, RoundedRectangle, and Capsule. Custom vector drawing can be accomplished by creating a struct that conforms to the Shape protocol as with the Arc shape in this example. Code for SwiftUI custom shapes found on GitHub or blogs can usually be copied straight into PDFBlocks.

PDF

example-vector.pdf

Code

struct ExampleVectorDrawing: Block {
    var body: some Block {
        Page(size: .letter, margins: .in(1)) {
            HStack(spacing: 32) {
                Arc(startAngle: .degrees(35), endAngle: .degrees(325), clockwise: false)
                    .fill(.yellow)
                    .stroke(.black, lineWidth: 3)
                    .frame(height: 150)
                Line(start: .leading, end: .trailing)
                    .stroke(.white, style: StrokeStyle(lineWidth: .pt(15), lineCap: .round, dash: [0, 80]))
                
            }
        }
        .background(.black)
        .border(.blue, width: 10)
    }
}

struct Arc: Shape {
    var startAngle: Angle
    var endAngle: Angle
    var clockwise: Bool

    func path(in rect: CGRect) -> Path {
        Path { path in
            let radius = min(rect.width, rect.height) / 2
            path.addLines([CGPoint(x: rect.midX, y: rect.midY)])
            path.addArc(center: CGPoint(x: rect.midX, y: rect.midY), radius: radius, startAngle: startAngle, endAngle: endAngle, clockwise: clockwise)
            path.closeSubpath()
        }
    }

    public func sizeThatFits(_ proposal: CGSize) -> CGSize {
        let minLength = min(proposal.width, proposal.height)
        return .init(width: minLength, height: minLength)
    }
}