init

common/colors/hex.go

@@ -0,0 +1,14 @@
+package colors
+
+import (
+	"image/color"
+)
+
+func FromInt(in int32) color.Color {
+	return color.RGBA{
+		uint8(in >> 16),
+		uint8(in >> 8),
+		uint8(in),
+		0xff,
+	}
+}

common/colors/hex_test.go

@@ -0,0 +1,62 @@
+package colors
+
+import (
+	"image/color"
+	"reflect"
+	"testing"
+)
+
+func TestFromInt(t *testing.T) {
+	type args struct {
+		in int32
+	}
+	tests := []struct {
+		name string
+		args args
+		want color.Color
+	}{
+		{
+			name: "black",
+			args: args{
+				in: 0x000000,
+			},
+			want: color.RGBA{
+				0, 0, 0, 0xff,
+			},
+		},
+		{
+			name: "red",
+			args: args{
+				in: 0xff0000,
+			},
+			want: color.RGBA{
+				0xff, 0, 0, 0xff,
+			},
+		},
+		{
+			name: "green",
+			args: args{
+				in: 0x00ff00,
+			},
+			want: color.RGBA{
+				0, 0xff, 0, 0xff,
+			},
+		},
+		{
+			name: "blue",
+			args: args{
+				in: 0x0000ff,
+			},
+			want: color.RGBA{
+				0, 0, 0xff, 0xff,
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := FromInt(tt.args.in); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("FromInt() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}