// Requires "go mod init main" and "go get github.com/holizz/terrapin" after
// You may need to install git first: https://git-scm.com/
package main
import (
"fmt"
"github.com/holizz/terrapin"
"image"
"image/png"
"math"
"net/http"
)
func kochCurve(t *terrapin.Terrapin, lung float64, liv int) {
if liv == 0 {
t.Forward(lung)
} else {
kochCurve(t, lung / 3, liv - 1)
t.Left(math.Pi / 3.0)
kochCurve(t, lung / 3, liv - 1)
t.Right(2.0 * math.Pi / 3.0)
kochCurve(t, lung/ 3, liv - 1)
t.Left(math.Pi / 3.0)
kochCurve(t, lung / 3, liv - 1)
}
}
func kochSnowflake(t *terrapin.Terrapin, lung float64, liv int) {
kochCurve(t, lung, liv)
t.Right(2.0 * math.Pi / 3.0)
kochCurve(t, lung, liv)
t.Right(2.0 * math.Pi / 3.0)
kochCurve(t, lung, liv)
t.Right(2.0 * math.Pi / 3.0)
}
func pageMain(w http.ResponseWriter, r *http.Request) {
w.Write([]byte(`
Koch
Koch
`))
}
func pageImage(w http.ResponseWriter, r *http.Request) {
i := image.NewRGBA(image.Rect(0, 0, 1000, 1000))
t := terrapin.NewTerrapin(i, terrapin.Position{200.0, 800.0})
kochSnowflake(t, 500.0, 5)
png.Encode(w, i)
}
func main() {
http.HandleFunc("/", pageMain)
http.HandleFunc("/koch.png", pageImage)
fmt.Println("Listening on http://localhost:3000/")
http.ListenAndServe("localhost:3000", nil)
}