add example tutorial 32 to demonstrate fillstyles

1 files changed, 76 insertions, 0 deletions

diff --git a/fpdf_test.go b/fpdf_test.go
index 9ac1e18..1f500fc 100644
--- a/fpdf_test.go
+++ b/fpdf_test.go
@@ -26,6 +26,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/jung-kurt/gofpdf"
@@ -1516,3 +1517,78 @@ func ExampleFpdf_tutorial31() {
 	// Output:
 	// Successfully generated pdf/tutorial31.pdf
 }
+
+// This example demonstrates the Path Drawing functions, such as: MoveTo,
+// LineTo, CurveTo, ..., ClosePath and DrawPath.
+func ExampleFpdf_tutorial32() {
+	pdf := gofpdf.New("P", "mm", "A4", "")
+	pdf.SetDrawColor(0xff, 0x00, 0x00)
+	pdf.SetFillColor(0x99, 0x99, 0x99)
+	pdf.SetFont("Helvetica", "", 15)
+	pdf.AddPage()
+	pdf.SetAlpha(1, "Multiply")
+	var (
+		polygon = func(cx, cy, r, n, dir float64) {
+			da := 2 * math.Pi / n
+			pdf.MoveTo(cx+r, cy)
+			pdf.Text(cx+r, cy, "0")
+			i := 1
+			for a := da; a < 2*math.Pi; a += da {
+				x, y := cx+r*math.Cos(dir*a), cy+r*math.Sin(dir*a)
+				pdf.LineTo(x, y)
+				pdf.Text(x, y, strconv.Itoa(i))
+				i += 1
+			}
+			pdf.ClosePath()
+		}
+		polygons = func(cx, cy, r, n, dir float64) {
+			d := 1.0
+			for rf := r; rf > 0; rf -= 10 {
+				polygon(cx, cy, rf, n, d)
+				d *= dir
+			}
+		}
+		star = func(cx, cy, r, n float64) {
+			da := 4 * math.Pi / n
+			pdf.MoveTo(cx+r, cy)
+			for a := da; a < 4*math.Pi+da; a += da {
+				x, y := cx+r*math.Cos(a), cy+r*math.Sin(a)
+				pdf.LineTo(x, y)
+			}
+			pdf.ClosePath()
+		}
+	)
+	// triangle
+	polygons(55, 45, 40, 3, 1)
+	pdf.DrawPath("B")
+	pdf.Text(15, 95, "B (same direction, non zero winding)")
+
+	// square
+	polygons(155, 45, 40, 4, 1)
+	pdf.DrawPath("B*")
+	pdf.Text(115, 95, "B* (same direction, even odd)")
+
+	// pentagon
+	polygons(55, 145, 40, 5, -1)
+	pdf.DrawPath("B")
+	pdf.Text(15, 195, "B (different direction, non zero winding)")
+
+	// hexagon
+	polygons(155, 145, 40, 6, -1)
+	pdf.DrawPath("B*")
+	pdf.Text(115, 195, "B* (different direction, even odd)")
+
+	// star
+	star(55, 245, 40, 5)
+	pdf.DrawPath("B")
+	pdf.Text(15, 290, "B (non zero winding)")
+
+	// star
+	star(155, 245, 40, 5)
+	pdf.DrawPath("B*")
+	pdf.Text(115, 290, "B* (even odd)")
+
+	pdf.OutputAndClose(docWriter(pdf, 32))
+	// Output:
+	// Successfully generated pdf/tutorial32.pdf
+}