From 77b2e273461b2b29f31eeed1e8a86505b3437883 Mon Sep 17 00:00:00 2001
From: Dennis Ranke <dennis.ranke@gmail.com>
Date: Wed, 23 Aug 2023 00:20:35 +0200
Subject: [PATCH] clamp snd samples into valid -1.0..1.0 range

---
 platform/src/ges.cwa |  3 +--
 src/run_native.rs    | 20 +++++++++++++++-----
 todo.txt             |  1 +
 3 files changed, 17 insertions(+), 7 deletions(-)
 create mode 100644 todo.txt

diff --git a/platform/src/ges.cwa b/platform/src/ges.cwa
index 9ea6c73..ca67c5f 100644
--- a/platform/src/ges.cwa
+++ b/platform/src/ges.cwa
@@ -62,7 +62,6 @@ export fn sndGes(t: i32) -> f32 {
             let phase = channelState!GesChannelState.Phase;
 
             let inline pulseWidth = channelReg?1;
-            let phaseShift = (pulseWidth - 128) * 255;
             let invPhaseInc = 1 as f32 / phaseInc as f32;
 
             i = 0;
@@ -131,7 +130,7 @@ export fn sndGes(t: i32) -> f32 {
                 let phaseInc = (freq * (65536.0 / 44100.0)) as i32;
 
                 let phase = channelState!GesChannelState.Phase;
-                if modSrc > ch {
+                if modSrc < ch {
                     phase = phase - (phaseInc << 6);
                 }
 
diff --git a/src/run_native.rs b/src/run_native.rs
index a9a982d..b011cdb 100644
--- a/src/run_native.rs
+++ b/src/run_native.rs
@@ -423,6 +423,14 @@ fn init_sound(
                     mem[64..68].copy_from_slice(&current_time.to_le_bytes());
                 }
 
+                fn clamp_sample(s: f32) -> f32 {
+                    if s.is_nan() {
+                        0.0
+                    } else {
+                        s.max(-1.0).min(1.0)
+                    }
+                }
+
                 if let Some(ref mut resampler) = resampler {
                     while !buffer.is_empty() {
                         let copy_size = resampler.output_buffers[0]
@@ -433,10 +441,12 @@ fn init_sound(
                             resampler.input_buffers[0].clear();
                             resampler.input_buffers[1].clear();
                             for _ in 0..resampler.resampler.input_frames_next() {
-                                resampler.input_buffers[0]
-                                    .push(snd.call(&mut store, (sample_index,)).unwrap_or(0.0));
-                                resampler.input_buffers[1]
-                                    .push(snd.call(&mut store, (sample_index + 1,)).unwrap_or(0.0));
+                                resampler.input_buffers[0].push(clamp_sample(
+                                    snd.call(&mut store, (sample_index,)).unwrap_or(0.0),
+                                ));
+                                resampler.input_buffers[1].push(clamp_sample(
+                                    snd.call(&mut store, (sample_index + 1,)).unwrap_or(0.0),
+                                ));
                                 sample_index = sample_index.wrapping_add(2);
                             }
 
@@ -462,7 +472,7 @@ fn init_sound(
                     }
                 } else {
                     for v in buffer {
-                        *v = snd.call(&mut store, (sample_index,)).unwrap_or(0.0);
+                        *v = clamp_sample(snd.call(&mut store, (sample_index,)).unwrap_or(0.0));
                         sample_index = sample_index.wrapping_add(1);
                     }
                 }
diff --git a/todo.txt b/todo.txt
new file mode 100644
index 0000000..44aff37
--- /dev/null
+++ b/todo.txt
@@ -0,0 +1 @@
+* add support for 16bit sound (not just float)