Scale a from input range (il to ih) to output range (ol to oh)
Syntaxscl(a,il,ih,ol,oh)
Original Machine Code (in OPER resource) of Filter Factory 3.0 and 3.0.4 for Photoshop/Win32
| 8B 6C 24 08 | mov ebp,[esp+$08] (param_ih) | . |
| 8B 4C 24 0C | mov ecx,[esp+$0c] (param_il) | . |
| 2B E9 | sub ebp,ecx | param_ih -= param_il; |
| 8B C5 | mov eax,ebp | eax = param_ih; |
| 74 15 | jz +$15 (@@1) | if (param_ih == 0) goto @@1; // return 0 |
| 8B 04 24 | mov eax,[esp] (param_oh) | eax = param_oh; |
| 8B 74 24 04 | mov esi,[esp+$04] (param_ol) | . |
| 2B C6 | sub eax,esi | eax -= param_ol; |
| 8B 54 24 10 | mov edx,[esp+$10] (param_a) | . |
| 2B D1 | sub edx,ecx | . |
| F7 EA | imul edx | eax *= param_a - param_il; |
| F7 FD | idiv ebp | eax /= param_ih; |
| 03 C6 | add eax,esi | eax += param_ol; // eax = (param_oh - param_ol) * (param_a - param_il) / param_ih + param_ol |
| @@1: | @@1: | |
| 83 C4 14 | add esp,$14 (= 5x pop) | . |
| 50 | push eax | return eax; |