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some oscillator optimization with fixed point phase to avoid casting ints

--- a/leaf/Src/leaf-oscillators.c

+++ b/leaf/Src/leaf-oscillators.c

@@ -47,25 +47,22 @@

 float   tCycle_tick(tCycle* const cy)

 {

     _tCycle* c = *cy;

-    float temp;

-    int idx;

-    float frac;

+    uint32_t tempFrac;

+    uint32_t idx;

     float samp0;

     float samp1;

     // Phasor increment

     c->phase += c->inc;

-

     // Wavetable synthesis

-

-    temp = ((float)c->phase * 0.000000476837158f);

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

+    idx = c->phase >> 21;

+    tempFrac = (c->phase & 2097151);

+    

     samp0 = __leaf_table_sinewave[idx];

     idx = (idx + 1) & c->mask;

     samp1 = __leaf_table_sinewave[idx];

-

-    return (samp0 + (samp1 - samp0) * frac);

+    

+    return (samp0 + (samp1 - samp0) * ((float)tempFrac * 0.000000476837386f)); // 1/2097151 (2097151 is the 21 bits after the 11 bits that represent the main index)

 }

 void     tCycle_setFreq(tCycle* const cy, float freq)

@@ -130,8 +127,7 @@

 {

     _tTriangle* c = *cy;

-    float temp;

-    int idx;

+    uint32_t idx;

     float frac;

     float samp0;

     float samp1;

@@ -138,24 +134,18 @@

     // Phasor increment

     c->phase += c->inc;

-    

     // Wavetable synthesis

-    temp = ((float)c->phase * 0.000000476837158f);

+    idx = c->phase >> 21;

+    uint32_t idx2 = (idx + 1) & c->mask;

+    uint32_t tempFrac = (c->phase & 2097151);

+    frac = (float)tempFrac * 0.000000476837386f;// 1/2097151 (2097151 is the 21 bits after the 11 bits that represent the main index)

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

     samp0 = __leaf_table_triangle[c->oct][idx];

-    idx = (idx + 1) & c->mask;

-    samp1 = __leaf_table_triangle[c->oct][idx];

-    

+    samp1 = __leaf_table_triangle[c->oct][idx2];

     float oct0 = (samp0 + (samp1 - samp0) * frac);

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

     samp0 = __leaf_table_triangle[c->oct+1][idx];

-    idx = (idx + 1) & c->mask;

-    samp1 = __leaf_table_triangle[c->oct+1][idx];

-    

+    samp1 = __leaf_table_triangle[c->oct+1][idx2];

     float oct1 = (samp0 + (samp1 - samp0) * frac);

     return oct0 + (oct1 - oct0) * c->w;

@@ -231,8 +221,7 @@

 {

     _tSquare* c = *cy;

-    float temp;

-    int idx;

+    uint32_t idx;

     float frac;

     float samp0;

     float samp1;

@@ -239,24 +228,18 @@

     // Phasor increment

     c->phase += c->inc;

-    

     // Wavetable synthesis

-    temp = ((float)c->phase * 0.000000476837158f);

+    idx = c->phase >> 21;

+    uint32_t idx2 = (idx + 1) & c->mask;

+    uint32_t tempFrac = (c->phase & 2097151);

+    frac = (float)tempFrac * 0.000000476837386f;// 1/2097151 (2097151 is the 21 bits after the 11 bits that represent the main index)

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

     samp0 = __leaf_table_squarewave[c->oct][idx];

-    idx = (idx + 1) & c->mask;

-    samp1 = __leaf_table_squarewave[c->oct][idx];

-    

+    samp1 = __leaf_table_squarewave[c->oct][idx2];

     float oct0 = (samp0 + (samp1 - samp0) * frac);

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

     samp0 = __leaf_table_squarewave[c->oct+1][idx];

-    idx = (idx + 1) & c->mask;

-    samp1 = __leaf_table_squarewave[c->oct+1][idx];

-    

+    samp1 = __leaf_table_squarewave[c->oct+1][idx2];

     float oct1 = (samp0 + (samp1 - samp0) * frac);

     return oct0 + (oct1 - oct0) * c->w;

@@ -332,8 +315,7 @@

 {

     _tSawtooth* c = *cy;

-    float temp;

-    int idx;

+    uint32_t idx;

     float frac;

     float samp0;

     float samp1;

@@ -340,26 +322,21 @@

     // Phasor increment

     c->phase += c->inc;

-    

     // Wavetable synthesis

-    temp = ((float)c->phase * 0.000000476837158f);

+    idx = c->phase >> 21;

+    uint32_t idx2 = (idx + 1) & c->mask;

+    uint32_t tempFrac = (c->phase & 2097151);

+    frac = (float)tempFrac * 0.000000476837386f; // 1/2097151 (2097151 is the 21 bits after the 11 bits that represent the main index)

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

     samp0 = __leaf_table_sawtooth[c->oct][idx];

-    idx = (idx + 1) & c->mask;

-    samp1 = __leaf_table_sawtooth[c->oct][idx];

-    

+    samp1 = __leaf_table_sawtooth[c->oct][idx2];

     float oct0 = (samp0 + (samp1 - samp0) * frac);

-    idx = ((int)temp) & c->mask;

-    frac = temp - (float)idx;

     samp0 = __leaf_table_sawtooth[c->oct+1][idx];

-    idx = (idx + 1) & c->mask;

-    samp1 = __leaf_table_sawtooth[c->oct+1][idx];

-    

+    samp1 = __leaf_table_sawtooth[c->oct+1][idx2];

     float oct1 = (samp0 + (samp1 - samp0) * frac);

+    

     return oct0 + (oct1 - oct0) * c->w;

 }

@@ -397,6 +374,7 @@

     c->invSampleRateTimesTwoTo32 = c->invSampleRate * TWO_TO_32;

     tSawtooth_setFreq(cy, c->freq);

 }

+

 #endif // LEAF_INCLUDE_SAWTOOTH_TABLE

 //==============================================================================