From d4e928c4eecdcb12ebc96054c92cfc7b701c9a83 Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@thinkpad.(none)>
Date: Sat, 12 Feb 2011 16:02:01 +0100
Subject: Sawtooth and pulse-waves have now variable phases

for sawtooth, the ratio rising:falling phase is adjustable
for pulse, the ratio high:low is adjustable
---
 TODO                |  4 ---
 TODO.done           |  4 +++
 synth/defines.h     | 29 +++++++++++++++++++++-
 synth/main.cpp      | 71 ++++++++++++++++++++++++++++++++++++++++++++---------
 synth/waveforms.txt | 67 +++++++++++++++++++++++++++++++++++++++-----------
 5 files changed, 143 insertions(+), 32 deletions(-)

diff --git a/TODO b/TODO
index cb13c19..d81ad27 100644
--- a/TODO
+++ b/TODO
@@ -5,10 +5,6 @@
     wenn man danach die noten spielen will. nicht reproduzierbar
 
 TODO für den synth
-   o square- und sawtooth mit einstellbarer pulsweite
-      -> invers-saw (0,1) = saw(1,0)
-      -> dreieck = saw(0.5,0.5)
-   o invertierter pulse-sin
    o file-watcher ist unsauber: inotify_map_mutex und prog_load_mutex
      werden eigentlich zu spät erstellt; bei EXTREM schnellen events
      könnte ein noch nicht existenter mutex gelockt werden
diff --git a/TODO.done b/TODO.done
index 56f7ed0..edd8294 100644
--- a/TODO.done
+++ b/TODO.done
@@ -82,6 +82,10 @@ TODO für den synth
   (o)bei filter-envelopes: ksr/ksl? nää.
   (o)resonanz-tremolo bei tiefpass? nää.
    * RAM aufräumen? [keine leaks, und linux macht das schon]
+   x square- und sawtooth mit einstellbarer pulsweite
+      -> invers-saw (0,1) = saw(1,0)
+      -> dreieck = saw(0.5,0.5)
+   x invertierter pulse-sin
 	 
 
 TODO fürs CLI
diff --git a/synth/defines.h b/synth/defines.h
index fb1d63b..1ec5b18 100644
--- a/synth/defines.h
+++ b/synth/defines.h
@@ -56,7 +56,34 @@ extern float LFO_FREQ_HZ[];
 
 
 #define WAVE_RES 44100
-#define N_WAVEFORMS 8
+
+
+// saw_start must be >= n_normal
+// pulse_start must be > saw_end
+// holes are allowed
+
+// 0..6 different stuff
+// 10..19 saw
+// 20..29 square is allowed, for example
+
+//SAW_N and PULSE_N should be odd numbers, otherwise you won't
+//get equal ratios for falling/rising or high/low
+//in english: you won't get a "normal" triangle wave or a "normal"
+//            square wave then
+#define N_NORMAL_WAVEFORMS 6
+#define WAVE_SAW_START 100
+#define WAVE_SAW_N 201
+#define WAVE_PULSE_START 400
+#define WAVE_PULSE_N 201
+
+#if ( (WAVE_SAW_START < N_NORMAL_WAVEFORMS) || \
+      (WAVE_PULSE_START < WAVE_SAW_START+WAVE_SAW_N) )
+  #error NORMAL WAVEFORMS, SAW- AND PULSE-WAVES MAY NOT OVERLAP!
+#endif
+
+#define N_WAVEFORMS (WAVE_PULSE_START+WAVE_PULSE_N)
+
+
 
 #define NO_CONT 128
 
diff --git a/synth/main.cpp b/synth/main.cpp
index 32b2b84..f9f1e57 100644
--- a/synth/main.cpp
+++ b/synth/main.cpp
@@ -96,22 +96,69 @@ int main(int argc, char** argv)
 			load_program(programfile[i],program_settings[i]);
 		}
 		
+		fixed_t* temp=new fixed_t[WAVE_RES];
+		for (i=0;i<WAVE_RES;i++)
+			temp[i]=0;
+		
 		for (i=0;i<N_WAVEFORMS;++i)
+			wave[i]=temp;
+		
+		for (i=0;i<N_NORMAL_WAVEFORMS;i++)
+			wave[i]=new fixed_t[WAVE_RES];
+		
+		for (i=WAVE_SAW_START; i<WAVE_SAW_START+WAVE_SAW_N; i++)
 			wave[i]=new fixed_t[WAVE_RES];
+					
+		for (i=WAVE_PULSE_START; i<WAVE_PULSE_START+WAVE_PULSE_N; i++)
+			wave[i]=new fixed_t[WAVE_RES];
+					
+		for (i=0;i<WAVE_RES;++i) //init the "normal" waves
+		{
+			fixed_t temp1, temp2;
+			temp1=ONE*sin(i*2.0*3.141592654/WAVE_RES);
+			temp2=ONE*sin(i*3.141592654/WAVE_RES);
+			wave[0][i]=temp1;
+			wave[1][i]=temp2;
+			wave[2][i]= (i<=WAVE_RES/2) ? temp1 : 0;
+			wave[3][i]= (i<=WAVE_RES/2) ? temp2 : 0;
+			wave[4][i]= (i<=WAVE_RES/2) ? 0 : temp2;
+			wave[5][i]=float(rand() - RAND_MAX/2) / (RAND_MAX/2) *ONE;
+		}
+
+		for (int j=WAVE_SAW_START; j<WAVE_SAW_START+WAVE_SAW_N; j++) //init the saws
+		{
+			float rising, falling;
+			falling=(float) (j-WAVE_SAW_START)/(WAVE_SAW_N-1);
+			rising=1.0-falling;
+
+			int a,b,c;
+			a=WAVE_RES*(rising/2);
+			b=WAVE_RES*(rising/2 + falling);
+			c=WAVE_RES*falling;
+			
+			for (i=0;i<a;i++)
+				wave[j][i]=ONE * i/a;
 			
-		for (i=0;i<WAVE_RES;++i)
+			for (i=a;i<b;i++)
+				wave[j][i]=ONE  -  2*ONE * (i-a)/c;
+				
+			for (i=b;i<WAVE_RES;i++)
+				wave[j][i]=ONE * (i-b)/a   -  ONE;
+		}
+		
+		for (int j=WAVE_PULSE_START; j<WAVE_PULSE_START+WAVE_PULSE_N; j++) //init the pulses
 		{
-			float temp1, temp2;
-			temp1=sin(i*2.0*3.141592654/WAVE_RES);
-			temp2=sin(i*3.141592654/WAVE_RES);
-			wave[0][i]=temp1*ONE;
-			wave[1][i]=temp2*ONE;
-			wave[2][i]=(i<=WAVE_RES/2) ? wave[0][i] : 0;
-			wave[3][i]= (i<=WAVE_RES/2) ? wave[1][i] : 0;
-			wave[4][i]=(i<WAVE_RES/2) ? ONE : -ONE;
-			wave[5][i]=(i<=WAVE_RES/2) ? (ONE*2*i/WAVE_RES) : (ONE*2*i/WAVE_RES - 2*ONE);
-			wave[6][i]=(i<=WAVE_RES/2) ? (ONE*2*i/WAVE_RES) : (ONE*2*(WAVE_RES-i)/WAVE_RES);
-			wave[7][i]=float(rand() - RAND_MAX/2) / (RAND_MAX/2) *ONE;
+			float high, low;
+			high=(float) (j-WAVE_PULSE_START)/(WAVE_PULSE_N-1);
+			low=1.0-high;
+			
+			int a=WAVE_RES*high;
+			
+			for (i=0;i<a;i++)
+				wave[j][i]=ONE;
+			
+			for (i=a;i<WAVE_RES;i++)
+				wave[j][i]=-ONE;
 		}
 		
 		for (int i=0;i<N_CHANNELS;++i)
diff --git a/synth/waveforms.txt b/synth/waveforms.txt
index efaa703..6439af4 100644
--- a/synth/waveforms.txt
+++ b/synth/waveforms.txt
@@ -13,18 +13,55 @@
 3 pulse-sine    /   |     /   |
                /    |____/    |____
                     
-                    _____     _____
-4 square            
-               _____     _____
-                       
-                       . |        . |
-5 sawtooth         . '   |    . '   |
-               . '       |. '       |
-                 
-                / \       / \
-6 triangle     /   \     /   \
-                    \   /     \   /
-                     \ /       \ /
-               
-7 noise        
-               
+                   ---.      ---.
+4 inverted         |   \     |   \
+  pulse-sine   ____|    \____|    \
+                    
+
+5 noise        
+
+
+100 to 300: sawtooth with variable rising/falling phases
+
+                                . |        . |
+100: normal sawtooth        . '   |    . '   |
+                        . '       |. '       |
+                                .          .
+in between                  . '  \     . '  \
+                        . '       \. '       \
+
+                         / \       / \
+200: triangle           /   \     /   \
+                             \   /     \   /
+                              \ /       \ /
+                          .          .
+in between               /  ' .     /  ' .
+                        /       ' ./       ' .
+
+                        | .        | .
+300: inverted sawtooth  |   ' .    |   ' .
+                        |       ' .|       ' .
+
+
+
+400 to 600: pulse with variable high/low ratio
+
+             1      
+400 DC       0 _   _   _   _   _   _  
+            -1 ____________________
+
+             1        ___       ___
+in between   0 _   _   _   _   _   _  
+            -1 _______   _______
+
+             1      _____     _____
+500 square   0 _   _   _   _   _   _  
+            -1 _____     _____
+
+             1    _______   _______
+in between   0 _   _   _   _   _   _  
+            -1 ___       ___  
+
+             1 ____________________
+600 DC       0 _   _   _   _   _   _  
+            -1 
-- 
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