Merge pull request #257 from MaSzyna-EU07/fix/vehicle-removal-smoke

fix(gfx): a vehicle taken off the tracks stops smoking (#90)

vehicle/DynObj.cpp

@@ -4852,7 +4852,7 @@ void TDynamicObject::RenderSounds() {
 #endif
      && ( // compound test whether the vehicle belongs to user-driven consist (as these don't emit outer noise in cab view)
             FreeFlyModeFlag ? true : // in external view all vehicles emit outer noise
-            // Global.pWorld->train() == nullptr ? true : // (can skip this check, with no player train the external view is a given)
+            simulation::Train == nullptr ? true : // no player train, e.g. it went through a portal and the view isn't switched yet
             ctOwner == nullptr ? true : // standalone vehicle, can't be part of user-driven train
             ctOwner != simulation::Train->Dynamic()->ctOwner ? true : // confirmed isn't a part of the user-driven train
             Global.CabWindowOpen ? true : // sticking head out we get to hear outer noise

vehicle/smoke.cpp

@@ -0,0 +1,46 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#include "stdafx.h"
+#include "vehicle/smoke.h"
+
+#include "McZapkie/MOVER.h"
+
+namespace smoke {
+
+namespace {
+
+// how hard the engine works, scaling the spawn rate of the source
+double engine_load(TMoverParameters const &Mover) {
+	if (Mover.dizel_spinup) {
+		// starting up, it puffs harder the faster it turns
+		return ((Mover.enrot / 4) * 0.01);
+	}
+	auto const rpmrise{(Mover.DElist[Mover.MainCtrlPosNo].RPM - Mover.enrot) / 60};
+	if (Mover.DirAbsolute == 0 || Mover.Im == 0) {
+		// idling: speeding up to the revolutions of the master controller
+		return ((rpmrise * 0.02) * (Mover.EnginePower * 0.005));
+	}
+	// under load: the more current the traction motors draw, the more smoke
+	return ((rpmrise * (std::sqrt(Mover.Im) * 0.01) * 0.02) * (Mover.EnginePower * 0.005));
+}
+
+} // namespace
+
+float vehicle_spawn_count(TMoverParameters const &Mover, bool const Ontracks, spawn_rate const &Rate, double const Timedelta) {
+	if (false == Ontracks) {
+		return 0.f;
+	}
+	// the steady rate of the source, the way a source of the scenery spawns...
+	auto const steady{std::min<float>(static_cast<float>(Rate.pending + (Rate.rate * Timedelta * Rate.fidelity)), Rate.limit)};
+	// ...and on top of it the share of the engine
+	return std::min<float>(static_cast<float>(steady + (Rate.rate * Timedelta * Rate.fidelity * engine_load(Mover))), Rate.limit);
+}
+
+} // namespace smoke

vehicle/smoke.h

@@ -0,0 +1,30 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#pragma once
+
+class TMoverParameters;
+
+// the smoke of a vehicle's engine, let out by the smoke sources of its model (rendering/particles.h)
+namespace smoke {
+
+// what a smoke source spawns, before the engine of its vehicle is taken into account
+struct spawn_rate {
+	float pending{0.f}; // particles left to spawn from the previous updates
+	float rate{0.f}; // particles per second
+	float fidelity{1.f}; // multiplier of the smoke settings
+	float limit{0.f}; // most particles the source can have
+};
+
+// number of particles the smoke source of a vehicle has to spawn after Timedelta seconds: the steady rate of the
+// source, plus a share which grows with the work of its engine. a vehicle taken off the tracks (Ontracks false: gone through a portal, or waiting in the pool of the road
+// traffic) puffs no more, the particles it already let out fade away as usual
+float vehicle_spawn_count(TMoverParameters const &Mover, bool Ontracks, spawn_rate const &Rate, double Timedelta);
+
+} // namespace smoke