From 98dcc095be7a24e02b704f47cdcfd1b8ac34a38e Mon Sep 17 00:00:00 2001
From: Louis Dalibard <ontake@ontake.dev>
Date: Fri, 17 Jan 2025 14:45:54 +0100
Subject: [PATCH] yes

---
 config/config.go |  6 ++++++
 main.go          | 23 ++++++++++++++++++-----
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/config/config.go b/config/config.go
index 8d5ef99..0839506 100644
--- a/config/config.go
+++ b/config/config.go
@@ -39,6 +39,9 @@ type ConfigS struct {
 	DefaultToSingleChannel           bool
 	PeakDetectSeparator              int
 	SingleChannelWindow              uint32
+	PeriodCrop                       bool
+	PeriodCropCount                  int
+	PeriodCropLoopOverCount          uint32
 }
 
 var DefaultConfig = ConfigS{
@@ -67,6 +70,9 @@ var DefaultConfig = ConfigS{
 	DefaultToSingleChannel:           false,
 	PeakDetectSeparator:              100,
 	SingleChannelWindow:              1200,
+	PeriodCrop:                       true,
+	PeriodCropCount:                  2,
+	PeriodCropLoopOverCount:          1,
 }
 
 var Config ConfigS
diff --git a/main.go b/main.go
index 3022d34..aa8a600 100644
--- a/main.go
+++ b/main.go
@@ -101,11 +101,24 @@ func (g *Game) Draw(screen *ebiten.Image) {
 
 		indices := peaks.Get(FFTBuffer, config.Config.PeakDetectSeparator)
 		sort.Ints(indices)
-		offset := uint32(indices[0])
-		for i := uint32(0); i < numSamples-1; i++ {
-			fAX := float32(FFTBuffer[(i+offset)%numSamples]) * config.Config.Gain * float32(scale)
-			fBX := float32(FFTBuffer[(i+1+offset)%numSamples]) * config.Config.Gain * float32(scale)
-			vector.StrokeLine(screen, float32(config.Config.WindowWidth)*float32(i%config.Config.SingleChannelWindow)/float32(config.Config.SingleChannelWindow), float32(config.Config.WindowHeight/2)+fAX, float32(config.Config.WindowWidth)*float32(i%config.Config.SingleChannelWindow+1)/float32(config.Config.SingleChannelWindow), float32(config.Config.WindowHeight/2)+fBX, config.Config.LineThickness, config.ThirdColorAdj, true)
+		offset := uint32(0)
+		if len(indices) != 0 {
+			offset = uint32(indices[0])
+		}
+		if config.Config.PeriodCrop && len(indices) > 1 {
+			lastPeriodOffset := uint32(indices[min(len(indices)-1, config.Config.PeriodCropCount)])
+			samplesPerCrop := lastPeriodOffset - offset
+			for i := uint32(0); i < min(numSamples, samplesPerCrop*config.Config.PeriodCropLoopOverCount)-1; i++ {
+				fAX := float32(FFTBuffer[(i+offset)%samplesPerCrop]) * config.Config.Gain * float32(scale)
+				fBX := float32(FFTBuffer[(i+1+offset)%samplesPerCrop]) * config.Config.Gain * float32(scale)
+				vector.StrokeLine(screen, float32(config.Config.WindowWidth)*float32(i%samplesPerCrop)/float32(samplesPerCrop), float32(config.Config.WindowHeight/2)+fAX, float32(config.Config.WindowWidth)*float32(i%samplesPerCrop+1)/float32(samplesPerCrop), float32(config.Config.WindowHeight/2)+fBX, config.Config.LineThickness, config.ThirdColorAdj, true)
+			}
+		} else {
+			for i := uint32(0); i < numSamples-1; i++ {
+				fAX := float32(FFTBuffer[(i+offset)%numSamples]) * config.Config.Gain * float32(scale)
+				fBX := float32(FFTBuffer[(i+1+offset)%numSamples]) * config.Config.Gain * float32(scale)
+				vector.StrokeLine(screen, float32(config.Config.WindowWidth)*float32(i%config.Config.SingleChannelWindow)/float32(config.Config.SingleChannelWindow), float32(config.Config.WindowHeight/2)+fAX, float32(config.Config.WindowWidth)*float32(i%config.Config.SingleChannelWindow+1)/float32(config.Config.SingleChannelWindow), float32(config.Config.WindowHeight/2)+fBX, config.Config.LineThickness, config.ThirdColorAdj, true)
+			}
 		}
 	}