SOFT_LIGHT

{@usesMathJax} Makes destination lighter or darker, depending on source.

Where \begin{equation} m = \begin{cases} C_{dst} / \alpha_{dst} &\alpha_{dst} \gt 0 \\ 0 &otherwise \end{cases} \end{equation}

\begin{equation} g = \begin{cases} (16 * m * m + 4 * m) * (m - 1) + 7 * m &4 * C_{dst} \leq \alpha_{dst} \\ \sqrt m - m &otherwise \end{cases} \end{equation}

\begin{equation} f = \begin{cases} C_{dst} * (\alpha_{src} + (2 * C_{src} - \alpha_{src}) * (1 - m)) &2 * C_{src} \leq \alpha_{src} \\ C_{dst} * \alpha_{src} + \alpha_{dst} * (2 * C_{src} - \alpha_{src}) * g &otherwise \end{cases} \end{equation}

\begin{equation} \alpha_{out} = \alpha_{src} + \alpha_{dst} - \alpha_{src} * \alpha_{dst} \end{equation} \begin{equation} C_{out} = C_{src} / \alpha_{dst} + C_{dst} / \alpha_{src} + f \end{equation}