From 4e770c258b9ad9f0239e2a7a91201b29b4b3e5f8 Mon Sep 17 00:00:00 2001
From: Alexis Murzeau <amubtdx@gmail.com>
Date: Mon, 8 Aug 2022 21:54:06 +0200
Subject: [PATCH] Fix flipper animation and angle calculation

Checked with a slowed down flipper (reduced retractTime and extendTime)
to ensure the flipper position is correct even when not finished while
pressing the flipper control.
---
 SpaceCadetPinball/TFlipper.cpp     |  4 ++--
 SpaceCadetPinball/TFlipperEdge.cpp | 21 +++++++++------------
 2 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/SpaceCadetPinball/TFlipper.cpp b/SpaceCadetPinball/TFlipper.cpp
index 4fece3b..bd40e5a 100644
--- a/SpaceCadetPinball/TFlipper.cpp
+++ b/SpaceCadetPinball/TFlipper.cpp
@@ -137,7 +137,7 @@ void TFlipper::TimerExpired(int timerId, void* caller)
 	auto flip = static_cast<TFlipper*>(caller);
 	int bmpCountSub1 = flip->ListBitmap->size() - 1;
 
-	auto newBmpIndex = static_cast<int>(floor((pb::time_now - flip->InputTime) / flip->TimerTime));
+	auto newBmpIndex = static_cast<int>(floor(flip->FlipperEdge->flipper_angle(pb::time_now) / flip->FlipperEdge->AngleMax * bmpCountSub1 + 0.5));
 	if (newBmpIndex > bmpCountSub1)
 		newBmpIndex = bmpCountSub1;
 	if (newBmpIndex < 0)
@@ -155,7 +155,7 @@ void TFlipper::TimerExpired(int timerId, void* caller)
 	}
 	if (flip->MessageField == 2)
 	{
-		flip->BmpIndex = bmpCountSub1 - newBmpIndex;
+		flip->BmpIndex = newBmpIndex;
 		if (flip->BmpIndex <= 0)
 		{
 			flip->BmpIndex = 0;
diff --git a/SpaceCadetPinball/TFlipperEdge.cpp b/SpaceCadetPinball/TFlipperEdge.cpp
index aa8c63b..7d17567 100644
--- a/SpaceCadetPinball/TFlipperEdge.cpp
+++ b/SpaceCadetPinball/TFlipperEdge.cpp
@@ -418,19 +418,17 @@ float TFlipperEdge::flipper_angle(float timeNow)
 {
 	if (!FlipperFlag)
 		return Angle1;
-	float angle = (Angle1 - Angle2) / AngleMax * AngleMult;
-	if (angle < 0.0f)
-		angle = -angle;
 
-	if (angle >= 0.0000001f)
-		angle = (timeNow - InputTime) / angle;
+	float currentAngleDuration = fabsf((Angle1 - Angle2) / AngleMax * AngleMult);
+	float currentAngleRatio;
+
+	if (currentAngleDuration >= 0.0000001f)
+		currentAngleRatio = (timeNow - InputTime) / currentAngleDuration;
 	else
-		angle = 1.0;
+		currentAngleRatio = 1.0;
 
-	angle = std::min(1.0f, std::max(angle, 0.0f));
-	if (FlipperFlag == 2)
-		angle = 1.0f - angle;
-	return angle * AngleMax;
+	currentAngleRatio = std::min(1.0f, std::max(currentAngleRatio, 0.0f));
+	return currentAngleRatio * (Angle1 - Angle2) + Angle2;
 }
 
 int TFlipperEdge::is_ball_inside(float x, float y)
@@ -482,8 +480,7 @@ void TFlipperEdge::SetMotion(int code, float value)
 	default: break;
 	}
 
-	if (!FlipperFlag)
-		InputTime = value;
+	InputTime = value;
 	FlipperFlag = code;
 	AngleStopTime = AngleMult + InputTime;
 }