OFF: This thing is available in polish servers since 2012, their idea was: "Let's say that we're in Devil's Catacomb and i want my client to be optimized, i enabled this option and all bosses/mobs become a dog, now everything is perfect, no lag anymore, WTF, we did metin2 great again, we're genius."
ON: Instead of this non-logic thing, you can enable/disable effects from mobs with game option, that's all what you need.
Inside of Area.cpp -> RenderEffect you could do a simple check for ignore specific type of effects for being rendered, also this change will be in real time, you don't need to close/open client.
I don't think is so hard, inside of loop function related about rendering effects you could do a check if your client is minimized to stop rendering them.
You could add this before __UpdateEffectList(), inside of void CArea::RenderEffect(). (i didn't test it)
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// Stop rendering effects while window is minimized.
const HWND hWnd = CPythonApplication::Instance().GetWindowHandle();
const bool isMinimized = static_cast<bool>(IsIconic(hWnd));
if (isMinimized)
return;
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