added play-sample tutorial and play-note-at (not working)

oregano/Tutorial.md

@@ -159,6 +159,32 @@ For example, if you want to control the cutoff frequency for a filter using the
 When the mouse is at the left of the screen, the frequency is 200, when the mouse is at the right, the frequency is 500.
 
 
+
+### Loading samples
+
+The syntax is
+
+* (load-sample file-name) ; returns a sample
+
+* (play-sample sample rate)
+
+`load-sample` returns a sample object which is passed to play-sample.
+
+The `rate`, an optional parameter, controls the frequency at which the sample is played. 1 means normal frequency. 2 is an octave above, and 0.5 is an octave below.
+
+Example:
+
+```scheme
+(define synth-hit1 (load-sample "/path/to/bass.wav"))
+
+(play-sample synth-hit1)
+
+(sleep 1)
+
+(play-sample synth-hit1 2)
+```
+
+
 ---
 ### Envelopes
 
@@ -194,12 +220,6 @@ These can be used in defining instruments.
 
 - comb
 
-### Loading samples
-
-* (load-sample file-name)
-
-* (play-sample sample)
-
 
 
 

oregano/instrument.rkt

@@ -1,7 +1,7 @@
 #lang racket
 
 
-(require rsc3 "system.rkt")
+(require rsc3 sosc/sosc "system.rkt")
 
 (provide
  (all-from-out rsc3))
@@ -90,10 +90,11 @@
 
 (struct note (id [freq #:mutable]) #:transparent)
 
-(define (create-synth name play-on-start)
+(define (create-synth name play-on-start [start -1])
   (define node-id (gen-node-id))
   (send-msg (s-new0 name node-id 1 1))
   ;; TODO - send in bundle. it run 0 may be sent after
+  
   ; don't make sound upon creation
   (if play-on-start
       empty
@@ -112,6 +113,14 @@
 (define (make-note inst-name freq)
   (make-note/option inst-name freq #f))
 
+(define (play-note-at start dur inst-name freq)
+  (define node-id (gen-node-id))
+  (send-msg (bundle start (mcons (s-new0 inst-name node-id 1 1)
+                                  (mcons (n-set1 node-id "freq" freq) '()))))
+  (send-msg (bundle (+ start dur) (mcons
+                                    (n-run1 node-id 0) '())))
+  (void))
+                                
 
 
 (define (note-on the-note)
@@ -125,7 +134,7 @@
   (void))
 
 (define (delete-note the-note)
-  (send-msg (n-free (note-id the-note)))
+  (send-msg (n-free1 (note-id the-note)))
   (void))
   
 
@@ -137,6 +146,7 @@
   (void))
 
 
+  
 (define (mouse/x start end)
   (mouse-x kr start end 0 0.1))