Davidjcobb

Given

${\begin{aligned}t&={\text{time since the shader was applied}}\\a_{\text{full}}&={\text{Full Alpha Ratio}}\\a_{\text{persistent}}&={\text{Persistent Alpha Ratio}}\\a_{\text{offset}}&=a_{\text{full}}-a_{\text{persistent}}\\t_{\text{fade-in}}&={\text{Alpha Fade In Time}}\\t_{\text{full}}&={\text{Alpha Fade In Time}}+{\text{Full Alpha Time}}\\t_{\text{fade-out}}&={\text{Alpha Fade Out Time}}\\t_{\text{end}}&={\text{time at which the shader was removed}}\\t_{\text{freq}}&={\text{Alpha Pulse Frequency}}\end{aligned}}$

the base alpha is defined as

$a_{\text{base}}={\begin{cases}a_{\text{full}}\times {\dfrac {t}{t_{\text{fade-in}}}},&{\text{if }}t_{\text{fade-in}}>0{\text{ and }}t\leq t_{\text{fade-in}}\\a_{\text{full}},&{\text{if }}t_{\text{fade-in}}=0{\text{ and }}t=0\\a_{\text{full}},&{\text{if }}t_{\text{full}}\geq t>t_{\text{fade-in}}\\a_{\text{persistent}}+(a_{\text{offset}}\times {\dfrac {t-t_{\text{full}}}{t_{\text{fade-out}}}}),&{\text{if }}t_{\text{full}}+t_{\text{fade-out}}>t>t_{\text{full}}\\a_{\text{persistent}}\times {\dfrac {t-t_{\text{end}}}{t_{\text{fade-out}}}},&{\text{if }}t_{\text{fade-out}}>0{\text{ and }}t>t_{\text{end}}\\0,&{\text{if }}t_{\text{fade-out}}=0{\text{ and }}t\geq t_{\text{end}}\end{cases}}$

and assuming that the alpha pulse uses a sine wave, the current alpha is

$a_{\text{current}}=a_{\text{base}}+sin()*t_{\text{freq}}$