img2gif

pkg/rotate/push.go

@@ -0,0 +1,23 @@
+package rotate
+
+import (
+	"image"
+	"math"
+)
+
+func Rotate(img image.Image, angle float64) image.Image {
+	newImg := image.NewRGBA(img.Bounds())
+	w, h := img.Bounds().Dx(), img.Bounds().Dy()
+	hh, hw := float64(h/2), float64(w/2)
+
+	for y := 0; y < w; y++ {
+		for x := 0; x < h; x++ {
+			newImg.Set(
+				int(hh-math.Cos(angle)),
+				int(hw-math.Sin(angle)),
+				img.At(x, y),
+			)
+		}
+	}
+	return newImg
+}