feat: move func to calc package

pkg/util/map_test.go

@@ -5,6 +5,7 @@ import (
 	"math"
 	"testing"
 
+	"galaxy/calc"
 	"galaxy/util"
 
 	"github.com/stretchr/testify/assert"
@@ -22,7 +23,7 @@ func TestShortDistance(t *testing.T) {
 		{10, 10, 8, 7, 1, 7, 3.},
 	} {
 		t.Run(fmt.Sprint(i), func(t *testing.T) {
-			d := util.ShortDistance(tc.w, tc.h, tc.x1, tc.y1, tc.x2, tc.y2)
+			d := calc.ShortDistance(tc.w, tc.h, tc.x1, tc.y1, tc.x2, tc.y2)
 			assert.Equal(t, tc.d, util.Fixed3(d))
 		})
 	}