Merge pull request #4 from lincollincol/develop

Fix amplitudes chunked function
lincollincol · Oct 7, 2022 · 60be437 · 60be437
2 parents 7fd46df + b4e438e
commit 60be437
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Showing 3 changed files with 39 additions and 37 deletions.
diff --git a/app/src/main/java/com/linc/audiowaveform/sample/ui/screen/waveform/AudioWaveformScreen.kt b/app/src/main/java/com/linc/audiowaveform/sample/ui/screen/waveform/AudioWaveformScreen.kt
@@ -103,28 +103,6 @@ fun AudioWaveformScreen(
                         scrollEnabled = true
                     }
                 )
-
-                AudioWaveform(
-                    modifier = Modifier.fillMaxWidth(),
-                    style = Fill,
-                    waveformAlignment = WaveformAlignment.Center,
-                    amplitudeType = AmplitudeType.Avg,
-                    progressBrush = SolidColor(Color.Magenta),
-                    waveformBrush = SolidColor(Color.LightGray),
-                    spikeWidth = 4.dp,
-                    spikePadding = 2.dp,
-                    spikeRadius = 4.dp,
-                    progress = uiState.progress,
-                    amplitudes = uiState.amplitudes,
-                    onProgressChange = {
-                        scrollEnabled = false
-                        onProgressChange(it)
-                    },
-                    onProgressChangeFinished = {
-                        scrollEnabled = true
-                    }
-                )
-
                 Divider(modifier = Modifier.padding(vertical = 8.dp))
                 LabelSlider(
                     text = stringResource(id = R.string.spike_width),

diff --git a/audiowaveform/src/main/java/com/linc/audiowaveform/AudioWaveform.kt b/audiowaveform/src/main/java/com/linc/audiowaveform/AudioWaveform.kt
@@ -35,6 +35,7 @@ private const val MaxProgress: Float = 1F
 
 private const val MinSpikeHeight: Float = 1F
 private const val DefaultGraphicsLayerAlpha: Float = 0.99F
+private const val AmplitudeMultiplier: Float = 2F
 
 @OptIn(ExperimentalComposeUiApi::class)
 @Composable
@@ -61,8 +62,8 @@ fun AudioWaveform(
     val _spikeTotalWidth = remember(spikeWidth, spikePadding) { _spikeWidth + _spikePadding }
     var canvasSize by remember { mutableStateOf(Size(0f, 0f)) }
     var spikes by remember { mutableStateOf(0F) }
-    val pixelAmplitudes = remember(amplitudes, spikes, amplitudeType) {
-        getPixelAmplitudes(
+    val spikesAmplitudes = remember(amplitudes, spikes, amplitudeType) {
+        getSpikesAmplitudes(
             amplitudeType = amplitudeType,
             amplitudes = amplitudes,
             spikes = spikes.toInt(),
@@ -95,7 +96,7 @@ fun AudioWaveform(
     ) {
         canvasSize = size
         spikes = size.width / _spikeTotalWidth.toPx()
-        pixelAmplitudes.forEachIndexed { index, amplitude ->
+        spikesAmplitudes.forEachIndexed { index, amplitude ->
             drawRoundRect(
                 brush = waveformBrush,
                 topLeft = Offset(
@@ -125,23 +126,25 @@ fun AudioWaveform(
     }
 }
 
-private fun getPixelAmplitudes(
+private fun getSpikesAmplitudes(
     amplitudeType: AmplitudeType,
     amplitudes: List<Int>,
     spikes: Int,
     minHeight: Float,
     maxHeight: Float
 ): List<Float> {
-    return when {
-        amplitudes.isEmpty() || spikes == 0 -> List(spikes) { minHeight }
-        amplitudes.count() < spikes -> amplitudes.map(Int::toFloat)
-        else -> amplitudes.chunked(amplitudes.count() / spikes)
-            .map {
-                when(amplitudeType) {
-                    AmplitudeType.Avg -> it.average()
-                    AmplitudeType.Max -> it.max()
-                    AmplitudeType.Min -> it.min()
-                }.toFloat().times(2).coerceIn(minHeight, maxHeight)
-            }
+    if(amplitudes.isEmpty() || spikes == 0) {
+        return List(spikes) { minHeight }
+    }
+    if(amplitudes.count() < spikes) {
+        return amplitudes.map(Int::toFloat)
     }
+    return amplitudes.map(Int::toFloat)
+        .chunkedToSize(spikes) {
+            when(amplitudeType) {
+                AmplitudeType.Avg -> it.average()
+                AmplitudeType.Max -> it.max()
+                AmplitudeType.Min -> it.min()
+            }.toFloat().times(AmplitudeMultiplier).coerceIn(minHeight, maxHeight)
+        }
 }
diff --git a/audiowaveform/src/main/java/com/linc/audiowaveform/Utils.kt b/audiowaveform/src/main/java/com/linc/audiowaveform/Utils.kt
@@ -0,0 +1,21 @@
+package com.linc.audiowaveform
+
+import kotlin.math.ceil
+import kotlin.math.roundToInt
+
+internal fun <T> Iterable<T>.chunkedToSize(size: Int, transform: (List<T>) -> T): List<T> {
+    val chunkSize = count() / size
+    val remainder = count() % size
+    val remainderIndex = ceil(count().safeDiv(remainder)).roundToInt()
+    val chunkIteration = filterIndexed { index, _ ->
+        remainderIndex == 0 || index % remainderIndex != 0
+    }.chunked(chunkSize, transform)
+    return when (size) {
+        chunkIteration.count() -> chunkIteration
+        else -> chunkIteration.chunkedToSize(size, transform)
+    }
+}
+
+internal fun Int.safeDiv(value: Int): Float {
+    return if(value == 0) return 0F else this / value.toFloat()
+}