Gives the contrast ratio between two colors.
| red |
The red component of the background color. |
| green |
The green component of the background color. |
| blue |
The blue component of the background color. |
| red2 |
The red component of the foreground color. |
| green2 |
The green component of the foreground color. |
| blue2 |
The blue component of the foreground color. |
1.0