Smarter handling of NULL buffers

.gitignore

@@ -1,5 +1,5 @@
 # ES-5-Pipewire
-es-5
+es-5-pipewire
 
 # ---> C
 # Prerequisites

Makefile

@@ -1,11 +1,11 @@
 CXX = gcc
 CXXFLAGS = -Wall
 LDLIBS =
-NAME = es-5
+NAME = es-5-pipewire
 LDLIBS += `pkg-config --cflags --libs libpipewire-0.3`
 
 es-5: es-5.c
-	$(CXX) $(CXXFLAGS) es-5.c -o $(NAME) $(LDLIBS)
+	$(CXX) $(CXXFLAGS) es-5.c -o $(NAME) $(LDLIBS) -lm
 
 all: es-5
 
@@ -13,4 +13,11 @@ clean:
 	rm ./$(NAME)
 
 run: all
-	./es-5
+	./$(NAME)
+
+debug: all
+	PIPEWIRE_DEBUG=5 ./$(NAME) 
+
+install: all
+	sudo mkdir -p /opt/$(NAME)
+	sudo cp ./$(NAME) /opt/$(NAME)/

README.md

@@ -1,2 +1,29 @@
 # ES-5-Pipewire
 
+A Pipewire client for the Expert Sleepers ES-5 eurorack module. Based upon [ES-5 Linx](https://github.com/CarlColglazier/ES-5Linx). This module takes eight gate inputs and converts them to a single output.
+
+## Setup
+
+### Requirements
+ - GCC
+ - Pipewire Development
+ 
+#### Fedora & RHEL
+```sh
+ sudo dnf install gcc pipewire-devel
+ ```
+#### Debian & Ubuntu
+ ```sh
+ sudo apt install gcc pipewire-dev
+ ```
+
+## Build
+ ```sh
+ make
+ ```
+## Install
+ ```sh
+ make install
+ ```
+ 
+ This will build the binary and copy it over to the `/opt/es-5-pipewire` directory.

es-5.c

@@ -1,7 +1,10 @@
+#include <math.h>
 #include <spa/param/latency-utils.h>
-
 #include <pipewire/pipewire.h>
 
+#define ES_5_RANGE 128
+#define GATE_LOW_EDGE 0.1
+
 struct data;
 
 struct port {
@@ -11,18 +14,40 @@ struct port {
 struct data {
   struct pw_main_loop *loop;
   struct pw_filter *filter;
-  struct port *in_port_one;
-  struct port *in_port_two;
-  struct port *in_port_three;
-  struct port *in_port_four;
-  struct port *in_port_five;
-  struct port *in_port_six;
-  struct port *in_port_seven;
-  struct port *in_port_eight;
+  struct port *in_ports[8];
   struct port *out_port;
 };
 
-static void on_process(void *userdata, struct spa_io_position *position) {}
+static void on_process(void *userdata, struct spa_io_position *position) {
+  struct data *data = userdata;
+  float *in, *out;
+  uint32_t i, n_samples = position->clock.duration;
+  float signal = 0.5f;
+  
+  // Read Inputs 1-7
+  out = pw_filter_get_dsp_buffer(data->out_port, n_samples);
+  if (out == NULL) return;
+  for (int input = 0; input < 7; input++) {
+    in = pw_filter_get_dsp_buffer(data->in_ports[input], n_samples);
+    if(in != NULL && *in > GATE_LOW_EDGE) {
+      signal += powf(2, input);
+    }
+  }
+
+  // Read Input 8
+  in = pw_filter_get_dsp_buffer(data->in_ports[7], n_samples);
+  if(in != NULL && *in > GATE_LOW_EDGE) {
+    signal = -ES_5_RANGE+signal;
+  }
+
+  // Convert signal to expect output scale
+  signal = signal / ES_5_RANGE;
+
+  // Send to output
+  for (i = 0; i < n_samples; i++) {
+    *out++ = signal;
+  }
+}
 
 static void do_quit(void *userdata, int signal_number) {
   struct data *data = userdata;
@@ -70,14 +95,14 @@ int main(int argc, char *argv[]) {
 				     &filter_events,
 				     &data);
 
-  data.in_port_one = add_port("input_1", data);
-  data.in_port_two = add_port("input_2", data);
-  data.in_port_three = add_port("input_3", data);
-  data.in_port_four = add_port("input_4", data);
-  data.in_port_five = add_port("input_5", data);
-  data.in_port_six = add_port("input_6", data);
-  data.in_port_seven = add_port("input_7", data);
-  data.in_port_eight = add_port("input_8", data);
+  data.in_ports[0] = add_port("input_1", data);
+  data.in_ports[1] = add_port("input_2", data);
+  data.in_ports[2] = add_port("input_3", data);
+  data.in_ports[3] = add_port("input_4", data);
+  data.in_ports[4] = add_port("input_5", data);
+  data.in_ports[5] = add_port("input_6", data);
+  data.in_ports[6] = add_port("input_7", data);
+  data.in_ports[7] = add_port("input_8", data);
 
   data.out_port = pw_filter_add_port(data.filter,
 				     PW_DIRECTION_OUTPUT,