clap

commit c3b21b3dc67ba0c4907d7c747c44abb7c99f57a3
parent 73ca1b6144ccb1628ed8573fe8041e3adda5f519
Author: Alexandre BIQUE <bique.alexandre@gmail.com>
Date:   Tue, 29 Jun 2021 13:17:30 +0200

Better DcOffset process loop

Diffstat:
M
examples/plugins/dc-offset/dc-offset.cc
 | 
35
++++++++++++++++++++++++-----------
M
examples/plugins/dc-offset/dc-offset.hh
 | 
9
+++------
M
include/clap/clap.h
 | 
10
+++++-----

3 files changed, 32 insertions(+), 22 deletions(-)
diff --git a/examples/plugins/dc-offset/dc-offset.cc b/examples/plugins/dc-offset/dc-offset.cc
@@ -68,22 +68,32 @@ namespace clap {
       audioOutputs_.push_back(info);
    }
 
-   bool DcOffset::activate(int sample_rate) noexcept { return true; }
-
-   void DcOffset::deactivate() noexcept { channelCount_ = 0; }
-
    clap_process_status DcOffset::process(const clap_process *process) noexcept {
       float **in = process->audio_inputs[0].data32;
       float **out = process->audio_outputs[0].data32;
       uint32_t evCount = process->in_events->size(process->in_events);
       uint32_t nextEvIndex = 0;
       const clap_event *ev = nullptr;
+      uint32_t N = process->frames_count;
 
-      for (int i = 0; i < process->frames_count; ++i) {
-         if (nextEvIndex < evCount) {
+      /* foreach frames */
+      for (uint32_t i = 0; i < process->frames_count; ++i) {
+
+         /* check if there are events to process */
+         for (; nextEvIndex < evCount; ++nextEvIndex) {
             ev = process->in_events->get(process->in_events, nextEvIndex);
-            if (ev->time != i)
+
+            if (ev->time < i) {
+               hostMisbehaving("Events must be ordered by time");
+               std::terminate();
+            }
+
+            if (ev->time > i)
+            {
+               // This event is in the future
+               N = std::min(ev->time, process->frames_count);
                break;
+            }
 
             switch (ev->type) {
             case CLAP_EVENT_PARAM_SET:
@@ -98,10 +108,13 @@ namespace clap {
             }
          }
 
-         float offset = offsetParam_->value();
-         for (int c = 0; c < channelCount_; ++c)
-            out[c][i] = in[c][i] + offset;
-         offsetParam_->step(1);
+         /* Process as many samples as possible until the next event */
+         for (; i < N; ++i) {
+            float offset = offsetParam_->value();
+            for (int c = 0; c < channelCount_; ++c)
+               out[c][i] = in[c][i] + offset;
+            offsetParam_->step(1);
+         }
       }
 
       return CLAP_PROCESS_CONTINUE_IF_NOT_QUIET;
diff --git a/examples/plugins/dc-offset/dc-offset.hh b/examples/plugins/dc-offset/dc-offset.hh
@@ -13,15 +13,12 @@ namespace clap {
       static const clap_plugin_descriptor *descriptor();
 
    protected:
-      // clap_plugin
-      bool                init() noexcept override;
-      void                defineAudioPorts() noexcept;
-      bool                activate(int sample_rate) noexcept override;
-      void                deactivate() noexcept override;
+      bool init() noexcept override;
+      void defineAudioPorts() noexcept;
       clap_process_status process(const clap_process *process) noexcept override;
 
    private:
-      int channelCount_ = 1;
+      int channelCount_ = 2;
       Parameter *offsetParam_ = nullptr;
    };
 } // namespace clap
 \ No newline at end of file
diff --git a/include/clap/clap.h b/include/clap/clap.h
@@ -63,14 +63,14 @@ typedef struct clap_audio_buffer {
    // Either data32 or data64 pointer will be set.
    float ** data32;
    double **data64;
-   int32_t  channel_count;
+   uint32_t channel_count;
    uint32_t latency;       // latency from/to the audio interface
    uint64_t constant_mask; // mask & (1 << N) to test if channel N is constant
 } clap_audio_buffer;
 
 typedef struct clap_process {
-   int64_t steady_time;  // a steady sample time counter, requiered
-   int32_t frames_count; // number of frame to process
+   uint64_t steady_time;  // a steady sample time counter, requiered
+   uint32_t frames_count; // number of frame to process
 
    // time info at sample 0
    // If null, then this is a free running host, no transport events will be provided
@@ -84,8 +84,8 @@ typedef struct clap_process {
    // then it gets a default stereo input and output.
    const clap_audio_buffer *audio_inputs;
    const clap_audio_buffer *audio_outputs;
-   int32_t                  audio_inputs_count;
-   int32_t                  audio_outputs_count;
+   uint32_t                 audio_inputs_count;
+   uint32_t                 audio_outputs_count;
 
    /* events */
    const clap_event_list *in_events;