1 files changed, 72 insertions, 0 deletions
diff --git a/src/osc.h b/src/osc.h
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--- /dev/null
+++ b/src/osc.h
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+#ifndef OSC_H
+#define OSC_H
+
+#include <math.h>
+  
+/**
+ * The main idea of the osc is the following:
+ * The root of the sound is a periodic wave function.
+ * This can be a stored period of a wave in a wavetable
+ * or a function like sin(). In order to play a sound with
+ * the wave an external float offset is kept that points to the
+ * next sample, a function is provided to advance this offset
+ * a calucalted step amount, depending on the desired frequency.
+ * Linear interpolation is used so that a float offset can work
+ * and provide autosmoothing.
+ */
+
+enum osc_type {
+  WAVE,
+  SAMPLE
+};
+
+typedef struct osc_t {
+  char name[16];
+  float * data;
+  long len;
+  long start;
+  long end;
+  enum osc_type type;
+} osc_t;
+
+/* Initializes the wavetables and functions for the oscilators */
+void init_osc();
+
+float osc_interpolate(float offset, float start, float end);
+float osc_next_offset(osc_t * osc, float f, float offset);
+int osc_next_index(osc_t * osc, float offset);
+
+int osc_load_wav(osc_t * osc, const char * path);
+
+/***************/
+/* OSCILATORS  */
+/***************/
+
+#define OSC_COMMON(osc)         \
+  void                          \
+  set_##osc##_start(long start) \
+  { OSC_##osc.start = start; }  \
+  void                          \
+  set_##osc##_end(long end)     \
+  { OSC_##osc.end = end; }
+
+#define OSC_COMMON_H(osc)        \
+  void                           \
+  set_##osc##_start(long start); \
+  void                           \
+  set_##osc##_end(long end);     \
+  float                          \
+  osc_##osc(float offset);       \
+  float                          \
+  osc_##osc##_next(float f, float offset);
+
+/*****************/
+/* osc functions */
+/*****************/
+
+OSC_COMMON_H(tri)
+OSC_COMMON_H(sin)
+OSC_COMMON_H(weird)
+OSC_COMMON_H(sound)
+
+#endif /* OSC_H */