mirror/sointu
1
0
Fork 0
mirror of https://github.com/vsariola/sointu.git synced 2025-07-19 05:24:48 -04:00
Code Issues Packages Projects Releases Wiki Activity

Change the sointu.h api to return -1, 0 or n>0 depending if buffer is full and/or row ended.

Browse Source 
test_render_samples_api.c was added to test the api. bridge.go was modified to reflect that there is no need to check for row manually; su_render_samples already returns the information if a row has ended.
This commit is contained in:
Veikko Sariola
2020-10-24 13:00:08 +03:00
parent c9e8000c5f
commit 6e85ff674a
7 changed files with 158 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files

54
include/sointu.h
View File

@ -38,9 +38,9 @@ typedef struct SynthState {
unsigned int Polyphony;
unsigned int NumVoices;
unsigned int RandSeed;
unsigned int Globaltime;
unsigned int GlobalTick;
unsigned int RowTick;
unsigned int RowLen;
unsigned int SamplesPerRow; // nominal value, actual rows could be more or less due to speed modulation
} SynthState;
#pragma pack(pop)
@ -58,22 +58,49 @@ typedef struct SynthState {
extern void CALLCONV su_load_gmdls(void);
#endif
// Returns the number of samples remaining in the buffer i.e. 0 if the buffer was
// filled completely.
// su_render_samples(SynthState* synthState, int maxSamples, float* buffer):
// Renders at most maxsamples to the buffer, using and modifying the
// synthesizer state in synthState.
//
// NOTE: The buffer should have a length of 2 * maxsamples, as the audio
// is stereo.
// Parameters:
// synthState pointer to current synthState. RandSeed should be > 0 e.g. 1
// Also synthState->SamplesPerRow cannot be 0 or nothing will be
// rendered; either set it to INT32_MAX to always render full
// buffer, or something like SAMPLE_RATE * 60 / (BPM * 4) for
// having 4 rows per beat.
// maxSamples maximum number of samples to be rendered. buffer should
// have a length of 2 * maxsamples as the audio is stereo.
// buffer audio sample buffer, L R L R ...
//
// You should always check if rowtick >= rowlen after calling this. If so, most
// likely you didn't get full buffer filled but the end of row was hit before
// filling the buffer. In that case, trigger/release new voices, set rowtick to 0.
// Returns:
// -1 end of row was not reached & buffer full
// 0 end of row was reached & buffer full (there is space for zero
// samples in the buffer)
// n>0 end of row was reached & there is space for n samples in the buffer
//
// Beware of infinite loops: with a rowlen of 0; or without resetting rowtick
// between rows; or with a problematic synth patch e.g. if the speed is
// modulated to be become infinite, this function might return maxsamples i.e. not
// render any samples. If you try to call this with your buffer until the whole
// buffer is filled, you will be stuck in an infinite loop.
extern int CALLCONV su_render_samples(SynthState* synthState, int maxsamples, float* buffer);
// modulated to be become infinite, this function might return maxsamples i.e.
// not render any samples. If you try to call this with your buffer until the
// whole buffer is filled, you will be stuck in an infinite loop.
//
// So a reasonable track player would be something like:
//
// function render_buffer(maxsamples,buffer) {
// remaining = maxsamples
// for i = 0..MAX_TRIES // limit retries to prevent infinite loop
// remaining = su_render_samples(synthState,
// remaining,
// &buffer[(maxsamples-remaining)*2])
// if remaining >= 0 // end of row reached
// song_row++ // advance row
// retrigger/release voices based on the new row
// if remaining <= 0 // buffer full
// return
// return // could not fill buffer despite MAX_TRIES, something is wrong
// // audio will come to sudden end
// }
extern int CALLCONV su_render_samples(SynthState* synthState, int maxSamples, float* buffer);
// Arithmetic opcode ids
extern const int su_add_id;
@ -110,7 +137,6 @@ extern const int su_send_id;
// Source opcode ids
extern const int su_envelope_id;
extern const int su_noise_id;
extern const int su_aux_id;
extern const int su_oscillat_id;
extern const int su_loadval_id;
extern const int su_receive_id;