Polygon function and demonstration

1 files changed, 48 insertions, 0 deletions

diff --git a/fpdf_test.go b/fpdf_test.go
index c727087..262e482 100644
--- a/fpdf_test.go
+++ b/fpdf_test.go
@@ -21,6 +21,7 @@ import (
 	"code.google.com/p/gofpdf"
 	"fmt"
 	"io/ioutil"
+	"math"
 	"os"
 	"path/filepath"
 	"strings"
@@ -1197,3 +1198,50 @@ func ExampleFpdf_tutorial24() {
 	// Output:
 	// Successfully generated pdf/tutorial24.pdf
 }
+
+// This example displays equilateral polygons in a demonstration of the Polygon
+// function.
+func ExampleFpdf_tutorial25() {
+	const rowCount = 5
+	const colCount = 4
+	const ptSize = 36
+	var x, y, radius, gap, advance float64
+	var rgVal int
+	var pts []gofpdf.PointType
+	vertices := func(count int) (res []gofpdf.PointType) {
+		var pt gofpdf.PointType
+		res = make([]gofpdf.PointType, 0, count)
+		mlt := 2.0 * math.Pi / float64(count)
+		for j := 0; j < count; j++ {
+			pt.Y, pt.X = math.Sincos(float64(j) * mlt)
+			res = append(res, gofpdf.PointType{x + radius*pt.X, y + radius*pt.Y})
+		}
+		return
+	}
+	pdf := gofpdf.New("P", "mm", "A4", cnFontDir) // A4 210.0 x 297.0
+	pdf.AddPage()
+	pdf.SetFont("Helvetica", "", ptSize)
+	pdf.SetDrawColor(0, 80, 180)
+	gap = 12.0
+	pdf.SetY(gap)
+	pdf.CellFormat(190.0, gap, "Equilateral polygons", "", 1, "C", false, 0, "")
+	radius = (210.0 - float64(colCount+1)*gap) / (2.0 * float64(colCount))
+	advance = gap + 2.0*radius
+	y = 2*gap + pdf.PointConvert(ptSize) + radius
+	rgVal = 230
+	for row := 0; row < rowCount; row++ {
+		pdf.SetFillColor(rgVal, rgVal, 0)
+		rgVal -= 12
+		x = gap + radius
+		for col := 0; col < colCount; col++ {
+			pts = vertices(row*colCount + col + 3)
+			// pdf.Circle(x, y, radius, "FD")
+			pdf.Polygon(pts, "FD")
+			x += advance
+		}
+		y += advance
+	}
+	pdf.OutputAndClose(docWriter(pdf, 25))
+	// Output:
+	// Successfully generated pdf/tutorial25.pdf
+}