From a61043e5703893636124eaa920f8e3f179ee15db Mon Sep 17 00:00:00 2001
From: Andrey <rusefillc@gmail.com>
Date: Tue, 16 Nov 2021 13:15:12 -0500
Subject: [PATCH] proportional spark cut #3427

---
 firmware/controllers/algo/engine.h           |  1 +
 firmware/controllers/algo/launch_control.cpp | 15 +++++++++++++++
 firmware/controllers/algo/launch_control.h   | 14 ++++++++++++++
 firmware/controllers/lua/lua_hooks.cpp       |  6 ++++++
 4 files changed, 36 insertions(+)

diff --git a/firmware/controllers/algo/engine.h b/firmware/controllers/algo/engine.h
index ac3bda259c..463e4a1d6a 100644
--- a/firmware/controllers/algo/engine.h
+++ b/firmware/controllers/algo/engine.h
@@ -115,6 +115,7 @@ public:
 
 	GearControllerBase *gearController;
 	LaunchControlBase launchController;
+	SoftSparkLimiter softSparkLimiter;
 
 	efitick_t mostRecentSparkEvent;
 	efitick_t mostRecentTimeBetweenSparkEvents;
diff --git a/firmware/controllers/algo/launch_control.cpp b/firmware/controllers/algo/launch_control.cpp
index 53cc6d6697..768c793842 100644
--- a/firmware/controllers/algo/launch_control.cpp
+++ b/firmware/controllers/algo/launch_control.cpp
@@ -137,6 +137,21 @@ bool LaunchControlBase::isLaunchFuelRpmRetardCondition() const {
 	return isLaunchRpmRetardCondition() && engineConfiguration->launchFuelCutEnable;
 }
 
+void SoftSparkLimiter::setTargetSkipRatio(float targetSkipRatio) {
+	this->targetSkipRatio = targetSkipRatio;
+}
+
+bool SoftSparkLimiter::shouldSkip()  {
+	if (targetSkipRatio == 0 || wasJustSkipped) {
+		wasJustSkipped = false;
+		return false;
+	}
+
+	float r = static_cast <float> (rand()) / static_cast <float> (RAND_MAX);
+	wasJustSkipped = r < 2 * targetSkipRatio;
+	return wasJustSkipped;
+}
+
 void initLaunchControl() {
 	engine->launchController.inject();
 }
diff --git a/firmware/controllers/algo/launch_control.h b/firmware/controllers/algo/launch_control.h
index dc70fba076..b42b569cdc 100644
--- a/firmware/controllers/algo/launch_control.h
+++ b/firmware/controllers/algo/launch_control.h
@@ -35,3 +35,17 @@ private:
 
 	Timer m_launchTimer;
 };
+
+
+class SoftSparkLimiter {
+public:
+	/**
+	 * targetSkipRatio of '0' means 'do not skip', would always return false
+	 */
+	void setTargetSkipRatio(float targetSkipRatio);
+
+	bool shouldSkip();
+private:
+	bool wasJustSkipped = false;
+	float targetSkipRatio = 0;
+};
diff --git a/firmware/controllers/lua/lua_hooks.cpp b/firmware/controllers/lua/lua_hooks.cpp
index 018006a927..06ad1adc09 100644
--- a/firmware/controllers/lua/lua_hooks.cpp
+++ b/firmware/controllers/lua/lua_hooks.cpp
@@ -486,6 +486,12 @@ void configureRusefiLuaHooks(lua_State* l) {
 			return 1;
 	});
 
+	lua_register(l, "setSparkSkipRatio", [](lua_State* l) {
+		auto targetSkipRatio = luaL_checknumber(l, 1);
+		engine->softSparkLimiter.setTargetSkipRatio(targetSkipRatio);
+		return 1;
+	});
+
 #if !EFI_UNIT_TEST
 	lua_register(l, "startPwm", lua_startPwm);
 	lua_register(l, "setPwmDuty", lua_setPwmDuty);