up3

server/internal/nbtconv/colour.go

@@ -0,0 +1,24 @@
+package nbtconv
+
+import (
+	"encoding/binary"
+	"image/color"
+)
+
+// Int32FromRGBA converts a color.RGBA into an int32. These int32s are present in, for example, signs.
+func Int32FromRGBA(x color.RGBA) int32 {
+	if x.R == 0 && x.G == 0 && x.B == 0 {
+		// Default to black colour. The default (0x000000) is a transparent colour. Text with this colour will not show
+		// up on the sign.
+		return int32(-0x1000000)
+	}
+	return int32(binary.BigEndian.Uint32([]byte{x.A, x.R, x.G, x.B}))
+}
+
+// RGBAFromInt32 converts an int32 into a color.RGBA. These int32s are present in, for example, signs.
+func RGBAFromInt32(x int32) color.RGBA {
+	b := make([]byte, 4)
+	binary.BigEndian.PutUint32(b, uint32(x))
+
+	return color.RGBA{A: b[0], R: b[1], G: b[2], B: b[3]}
+}