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https://github.com/ekeeke/Genesis-Plus-GX.git
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52 lines
1.9 KiB
C
52 lines
1.9 KiB
C
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/* Fast sound synthesis buffer for use in real-time emulators of electronic
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sound generator chips like those in early video game consoles. Uses linear
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interpolation. Higher-quality versions are available that use sinc-based
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band-limited synthesis. */
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#ifndef BLIP_H
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#define BLIP_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* Creates a new blip_buffer with specified input clock rate, output
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sample rate, and size (in samples), or returns NULL if out of memory. */
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typedef struct blip_buffer_t blip_buffer_t;
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blip_buffer_t* blip_alloc( double clock_rate, double sample_rate, int size );
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/* Frees memory used by a blip_buffer. No effect if NULL is passed. */
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void blip_free( blip_buffer_t* );
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/* Removes all samples and clears buffer. */
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void blip_clear( blip_buffer_t* );
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/* Adds an amplitude transition of delta at specified time in source clocks.
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Delta can be negative. */
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void blip_add( blip_buffer_t*, int time, int delta );
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/* Number of additional clocks needed until n samples will be available.
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If buffer cannot even hold n samples, returns number of clocks until buffer
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becomes full. */
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int blip_clocks_needed( const blip_buffer_t*, int samples_needed );
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/* Ends current time frame of specified duration and make its samples available
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(along with any still-unread samples) for reading with read_samples(), then
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begins a new time frame at the end of the current frame. */
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void blip_end_frame( blip_buffer_t*, int duration );
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/* Number of samples available for reading with read(). */
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int blip_samples_avail( const blip_buffer_t* );
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/* Reads at most n samples out of buffer into out, removing them from from
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the buffer. Returns number of samples actually read and removed. If stereo is
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true, increments 'out' one extra time after writing each sample, to allow
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easy interleving of two channels into a stereo output buffer. */
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int blip_read_samples( blip_buffer_t*, short out [], int n, int stereo );
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#ifdef __cplusplus
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}
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#endif
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#endif
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