Merge lp:~mixxxdevelopers/mixxx/fixes_scratch into lp:~mixxxdevelopers/mixxx/trunk

[Albert Santoni]

[Albert Santoni (gamegod)]

Needs testing with SCS.3d and vinyl control.

[lp:~mixxxdevelopers/mixxx/fixes_scratch]

2363. By Sean M. Pappalardo on 2010-04-29

- Added new behavior flag to common scripts so old behavior can still work seamlessly, SCS.3d script uses new (This flag will be removed after the deprecation period)
- Fixed variable naming errors in common scripts!
- Added line breaks to long print lines

[Albert Santoni (gamegod)]

Changes to the engine are minimal. Approving...

review: Approve

=== modified file 'mixxx/res/midi/Stanton-SCS3d-scripts.js'
--- mixxx/res/midi/Stanton-SCS3d-scripts.js	2010-03-06 21:46:14 +0000
+++ mixxx/res/midi/Stanton-SCS3d-scripts.js	2010-04-29 07:06:29 +0000
@@ -23,9 +23,8 @@
 StantonSCS3d.deckChangeWait = 1000;     // Time in milliseconds to hold the DECK button down to avoid changing decks (multi deck mode)
 
 // These values are heavily latency-dependent. They're preset for 10ms and will need tuning for other latencies. (For 2ms, try 0.885, 0.15, and 1.5.)
-StantonSCS3d.scratching = {     "slippage":0.8,             // Slipperiness of the virtual slipmat when scratching with the circle (higher=slower response, 0<n<1)
-                                "sensitivity":0.2,          // How much the audio moves for a given circle arc (higher=faster response, 0<n<1)
-                                "stoppedMultiplier":1.7 };  // Correction for when the deck is stopped (set higher for higher latencies)
+StantonSCS3d.scratching = {     "slippage":0.7,             // Slipperiness of the virtual slipmat when scratching with the circle (higher=slower response, 0<n<1)
+                                "sensitivity":0.2 };        // How much the audio moves for a given circle arc (higher=faster response, 0<n<1)
 
 // ----------   Other global variables    ----------
 StantonSCS3d.debug = false;  // Enable/disable debugging messages to the console
@@ -47,7 +46,7 @@
 StantonSCS3d.surface = { "C1":0x00, "S5":0x01, "S3":0x02, "S3+S5":0x03, "Buttons":0x04 };
 StantonSCS3d.sysex = [0xF0, 0x00, 0x01, 0x60];  // Preamble for all SysEx messages for this device
 // Variables used in the scratching alpha-beta filter: (revtime = 1.8 to start)
-StantonSCS3d.scratch = { "revtime":1.8, "alpha":0.1, "beta":1.0, "touching":false };
+StantonSCS3d.scratch = { "revtime":4.0, "alpha":0.1, "beta":1.0, "touching":false };
 StantonSCS3d.trackDuration = [0,0]; // Duration of the song on each deck (used for vinyl LEDs)
 StantonSCS3d.lastLight = [-1,-1]; // Last circle LED values
 StantonSCS3d.lastLoop = 0;  // Last-used loop LED
@@ -667,11 +666,8 @@
         case "vinyl":
         case "vinyl2":
             // So we don't get stuck at some strange speed when switching from a scratching mode
-            engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", 0);
-            if (StantonSCS3d.scratch["wasPlaying"]) {   // to avoid getting stuck stopped
-                engine.setValue("[Channel"+StantonSCS3d.deck+"]","play",1);
-                StantonSCS3d.scratch["wasPlaying"] = false;
-            }
+            engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2_enable", 0);
+            engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", 0);
             break;
         case "loop2":
         case "loop3":
@@ -855,11 +851,9 @@
     StantonSCS3d.modifier["deck"]=0;   // Clear button modifier flag
     StantonSCS3d.connectSurfaceSignals(channel,true);   // Disconnect surface signals & turn off surface LEDs
     StantonSCS3d.mode_store["[Channel"+StantonSCS3d.deck+"]"] = StantonSCS3d.state["deckPrev"];
-    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", 0); // To avoid getting stuck at a weird speed
-    if (StantonSCS3d.scratch["wasPlaying"]) {   // to avoid the deck stopping
-        engine.setValue("[Channel"+StantonSCS3d.deck+"]","play",1);
-        StantonSCS3d.scratch["wasPlaying"] = false;
-    }
+    // To avoid getting stuck at a weird speed
+    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2_enable", 0);
+    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", 0);
     var newMode;
     // In default multiple-deck mode, 
     //      If the button's been held down for longer than the specified time, stay on the current deck.
@@ -960,12 +954,12 @@
     if (currentMode=="vinyl2" && StantonSCS3d.vinyl2ScratchMethod=="pp") {
         var group = "[Channel"+StantonSCS3d.deck+"]";
         var jogValue = (value-64);
-        if (engine.getValue(group,"play")==1 && engine.getValue(group,"reverse")==1) jogValue= -(jogValue);
+        if (engine.getValue(group,"reverse")==1) jogValue= -(jogValue);
 
-        var multiplier = StantonSCS3d.scratching["sensitivity"] * (engine.getValue(group,"play") ? 1 : StantonSCS3d.scratching["stoppedMultiplier"] );
+        var multiplier = StantonSCS3d.scratching["sensitivity"]/2;
 //              if (StantonSCS3d.debug) print("do scratching VALUE:" + value + " jogValue: " + jogValue );
         multiplier = multiplier * 0.5;  // Reduce sensitivity of the slider since it's lower res
-        engine.setValue(group,"scratch", (engine.getValue(group,"scratch") + (jogValue * multiplier)).toFixed(2));
+        engine.setValue(group,"scratch2", (engine.getValue(group,"scratch2") + (jogValue * multiplier)).toFixed(2));
     }
 }
 
@@ -996,12 +990,12 @@
             var byte1 = 0xB0 + channel;
             midi.sendShortMsg(byte1,0x01,add); //S4 LEDs
             if (!StantonSCS3d.VUMeters || StantonSCS3d.deck!=1) midi.sendShortMsg(byte1,0x0C,add); //S3 LEDs
-            if (!StantonSCS3d.VUMeters || StantonSCS3d.deck!=2)midi.sendShortMsg(byte1,0x0E,add); //S5 LEDs
+            if (!StantonSCS3d.VUMeters || StantonSCS3d.deck!=2) midi.sendShortMsg(byte1,0x0E,add); //S5 LEDs
             
             if (currentMode=="vinyl" || StantonSCS3d.vinyl2ScratchMethod == "a-b") {    // this is only for the alpha-beta filter implementation
                 // Call global scratch slider function
                 var newScratchValue = scratch.slider(StantonSCS3d.deck, value, StantonSCS3d.scratch["revtime"], StantonSCS3d.scratch["alpha"], StantonSCS3d.scratch["beta"]);
-                engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch",newScratchValue);
+                engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2",newScratchValue);
             }
             break;
         case "loop2":
@@ -1081,13 +1075,12 @@
         switch (currentMode) {
 //             case "vinyl":
             case "vinyl2":
-                if (StantonSCS3d.vinyl2ScratchMethod == "a-b") scratch.enable(StantonSCS3d.deck);
+                if (StantonSCS3d.vinyl2ScratchMethod == "a-b") scratch.enable(StantonSCS3d.deck, true);
                 else {
                     StantonSCS3d.scratch["touching"] = true;
+                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2_enable", 1);
                     if (engine.getValue("[Channel"+StantonSCS3d.deck+"]","play")==1) {
-                        engine.setValue("[Channel"+StantonSCS3d.deck+"]","play",0);
-                        engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch",(1+engine.getValue("[Channel"+StantonSCS3d.deck+"]","scratch")));  // So it ramps down when you touch
-                        StantonSCS3d.scratch["wasPlaying"] = true;
+                        engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2",(1+engine.getValue("[Channel"+StantonSCS3d.deck+"]","scratch2")));  // So it ramps down when you touch
                     }
                 }
                 break;
@@ -1098,7 +1091,9 @@
             case "vinyl": break;
             case "vinyl2":
                 if (StantonSCS3d.vinyl2ScratchMethod == "a-b") scratch.disable(StantonSCS3d.deck);
-                else StantonSCS3d.scratch["touching"] = false;
+                else {
+                    StantonSCS3d.scratch["touching"] = false;
+                }
                 break;
             default: midi.sendShortMsg(byte1,0x62,0x00); // Turn off C1 lights
                 break;
@@ -1143,13 +1138,14 @@
         switch (currentMode) {
             case "vinyl":   // Store scratch info the point it was touched
             case "vinyl2":
-                if (currentMode=="vinyl" || StantonSCS3d.vinyl2ScratchMethod == "a-b") scratch.enable(StantonSCS3d.deck);
+                if (currentMode=="vinyl" || StantonSCS3d.vinyl2ScratchMethod == "a-b") scratch.enable(StantonSCS3d.deck, true);
                 else {
                     StantonSCS3d.scratch["touching"] = true;
+                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2_enable", 1);
                     if (engine.getValue("[Channel"+StantonSCS3d.deck+"]","play")==1) {
-                        engine.setValue("[Channel"+StantonSCS3d.deck+"]","play",0);
-                        engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch",(1+engine.getValue("[Channel"+StantonSCS3d.deck+"]","scratch")));  // So it ramps down when you touch
-                        StantonSCS3d.scratch["wasPlaying"] = true;
+                        // So it ramps down when you touch
+                        engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2",
+                                        (1+engine.getValue("[Channel"+StantonSCS3d.deck+"]","scratch2")));
                     }
                 }
                 break;
@@ -1179,7 +1175,9 @@
         case "vinyl":   // Reset the triggers
         case "vinyl2":
             if (currentMode=="vinyl" || StantonSCS3d.vinyl2ScratchMethod == "a-b") scratch.disable(StantonSCS3d.deck);
-            else StantonSCS3d.scratch["touching"] = false;
+            else {
+                StantonSCS3d.scratch["touching"] = false;
+            }
             var byte1a = 0xB0 + channel;
             midi.sendShortMsg(byte1a,0x01,0x00); //S4 LEDs off
             if (!StantonSCS3d.VUMeters || StantonSCS3d.deck!=1) midi.sendShortMsg(byte1a,0x0C,0x00); //S3 LEDs off
@@ -1305,7 +1303,6 @@
     var currentMode = StantonSCS3d.mode_store["[Channel"+StantonSCS3d.deck+"]"];
     switch (currentMode) {
         case "vinyl":
-//             if (currentMode=="deck") return;   // ignore if the cross-fader is being adjusted
             var newValue=(value-64);
 //             print("C1="+value+", jog="+newValue);
             engine.setValue("[Channel"+StantonSCS3d.deck+"]","jog",newValue);
@@ -1316,12 +1313,11 @@
             var jogValue = (value-64);
             if (engine.getValue(group,"play")==1 && engine.getValue(group,"reverse")==1) jogValue= -(jogValue);
             
-            var multiplier = StantonSCS3d.scratching["sensitivity"] * (engine.getValue(group,"play") ? 1 : StantonSCS3d.scratching["stoppedMultiplier"] );
+            var multiplier = StantonSCS3d.scratching["sensitivity"];
 //              if (StantonSCS3d.debug) print("do scratching VALUE:" + value + " jogValue: " + jogValue );
-            engine.setValue(group,"scratch", (engine.getValue(group,"scratch") + (jogValue * multiplier)).toFixed(2));
+            engine.setValue(group,"scratch2", (engine.getValue(group,"scratch2") + (jogValue * multiplier)).toFixed(2));
             break;
         case "vinyl3":
-//             if (currentMode=="deck") return;   // ignore if the cross-fader is being adjusted
             if ((value-64)>0) {
                 engine.setValue("[Playlist]","SelectNextTrack",1);
             }
@@ -1339,7 +1335,7 @@
 //             // Slower response for jog wheel
 //             var newValue = scratch.wheel(StantonSCS3d.deck, value, 1.8, StantonSCS3d.scratch["alpha"], 1.0);
 //             print("StantonSCS3d: newValue="+newValue);
-//             engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch",newValue);
+//             engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2",newValue);
             break;
         case "vinyl2": 
             if (StantonSCS3d.vinyl2ScratchMethod != "a-b") break;   // this is only for the alpha-beta filter implementation
@@ -1349,7 +1345,7 @@
             // Call global scratch wheel function
             var newScratchValue = scratch.wheel(StantonSCS3d.deck, value, StantonSCS3d.scratch["revtime"], StantonSCS3d.scratch["alpha"], StantonSCS3d.scratch["beta"]);
                 
-            engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch",newScratchValue);
+            engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2",newScratchValue);
             break;
         default:
             // Light the LEDs
@@ -1688,7 +1684,8 @@
     }
     
     // Revolution time of the imaginary record in seconds
-    var revtime = StantonSCS3d.scratch["revtime"];
+    var revtime = 1.8;  // 1.8s at 33 1/3 RPM
+//     var revtime = StantonSCS3d.scratch["revtime"];
     if (StantonSCS3d.spinningLights==2) revtime = StantonSCS3d.scratch["revtime"]/2;    // Use this for two lights
     var currentTrackPos = value * StantonSCS3d.trackDuration[StantonSCS3d.deck];
     
@@ -1710,34 +1707,38 @@
 StantonSCS3d.wheelDecay = function (value) {
 
     if (StantonSCS3d.mode_store["[Channel"+StantonSCS3d.deck+"]"]=="vinyl2") {    // Only in Vinyl2 mode
-        var scratch = engine.getValue("[Channel"+StantonSCS3d.deck+"]","scratch");
-        var jogDecayRate = StantonSCS3d.scratching["slippage"] * (engine.getValue("[Channel"+StantonSCS3d.deck+"]","play") ? 1 : 1.1 );
+        var scratch = engine.getValue("[Channel"+StantonSCS3d.deck+"]","scratch2");
+        var jogDecayRate = StantonSCS3d.scratching["slippage"] * 1.1;   // 0.2
         
-        if (StantonSCS3d.debug) print("Scratch deck"+StantonSCS3d.deck+": " + scratch + ", Jog decay rate="+jogDecayRate);
+//         if (StantonSCS3d.debug) print("Scratch deck"+StantonSCS3d.deck+": " + scratch + ", Jog decay rate="+jogDecayRate);
         
         // If it was playing, ramp back to playback speed
-        if (StantonSCS3d.scratch["wasPlaying"] && !StantonSCS3d.scratch["touching"]) {
+        if (engine.getValue("[Channel"+StantonSCS3d.deck+"]","play")==1 && !StantonSCS3d.scratch["touching"]) {
             var rate = engine.getValue("[Channel"+StantonSCS3d.deck+"]","rate") * engine.getValue("[Channel"+StantonSCS3d.deck+"]","rateRange");
             var convergeTo = 1+rate;
-            //jogDecayRate = StantonSCS3d.scratching["slippage"] * 0.2;
             if (scratch != convergeTo) { // Thanks to jusics on IRC for help with this part
-                if (Math.abs(scratch-convergeTo) > jogDecayRate*0.001) {  
-                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", (convergeTo + (scratch-convergeTo) * jogDecayRate).toFixed(5));
-                    //engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", (scratch + (convergeTo - scratch) / jogDecayRate).toFixed(5));
+                if (Math.abs(scratch-convergeTo) > jogDecayRate*0.001) {
+                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", 
+                                    (convergeTo + (scratch-convergeTo) * jogDecayRate).toFixed(5));
+                    //engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", (scratch + (convergeTo - scratch) / jogDecayRate).toFixed(5));
                 } else {
-                    // Once "scratch" has gotten close enough to the play speed, just resume normal playback
-                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", 0);
-                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","play",1);
-                    StantonSCS3d.scratch["wasPlaying"] = false;
+                    // Once "scratch2" has gotten close enough to the play speed, just resume normal playback
+                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", 0);
+                    engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2_enable", 0);
                 }
             }
-        } else
-        if (scratch != 0) { // For regular scratching when stopped or if playing (and ramp down...touch functions set scratch=1 and play=0)
-            if (Math.abs(scratch) > jogDecayRate*0.001) {  
-                  engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", (scratch * jogDecayRate).toFixed(4));
-               } else {
-                  engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch", 0);
-               }
+        }
+        else if (scratch != 0) {
+            // For regular scratching when stopped or if playing and ramp down
+            if (Math.abs(scratch) > jogDecayRate*0.001) {
+                var value=(scratch * jogDecayRate).toFixed(5);
+                engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", value);
+                if (StantonSCS3d.debug) print("Scratch deck"+StantonSCS3d.deck+": " + value + ", Jog decay rate="+jogDecayRate);
+            } else {
+                engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2", 0);
+                if (!StantonSCS3d.scratch["touching"]) engine.setValue("[Channel"+StantonSCS3d.deck+"]","scratch2_enable", 0);
+                if (StantonSCS3d.debug) print("Scratch deck"+StantonSCS3d.deck+": 0, Jog decay rate="+jogDecayRate);
+            }
         }
     }
 }

=== modified file 'mixxx/res/midi/midi-mappings-scripts.js'
--- mixxx/res/midi/midi-mappings-scripts.js	2010-03-20 02:33:20 +0000
+++ mixxx/res/midi/midi-mappings-scripts.js	2010-04-29 07:06:29 +0000
@@ -33,7 +33,7 @@
     msecs = Math.round(msecs * 100 / 1000);
     if (msecs==100) msecs=99;
     
-    print("secs="+secs+", msecs="+msecs);
+//     print("secs="+secs+", msecs="+msecs);
 
     return (m < 10 ? "0" + m : m) 
         + ":"
@@ -43,8 +43,10 @@
 }
 
 function script() {}
-script.debug = function (channel, control, value, status) {
-    print("Script.Debug --- channel: " + channel.toString(16) + " control: " + control.toString(16) + " value: " + value.toString(16) + " status: " + status.toString(16));
+script.debug = function (channel, control, value, status, group) {
+    print("Script.Debug --- channel: " + channel.toString(16) + 
+          " control: " + control.toString(16) + " value: " + value.toString(16) + 
+          " status: " + status.toString(16) + " group: " + group);
 }
 
 // Used to control a generic Mixxx control setting (low..high) from an absolute control (0..127)
@@ -64,7 +66,9 @@
 script.absoluteEQ = function (group, key, value) {
     if (value<=64) engine.setValue(group, key, value/64);
     else engine.setValue(group, key, 1+(value-63)/(21+1/3));
-    print ("MIDI Script: script.absoluteEQ is deprecated. Use script.absoluteNonLin(value,0,1,4) instead and set the MixxxControl to its return value.");
+    print ("MIDI Script: script.absoluteEQ is deprecated. " + 
+           "Use script.absoluteNonLin(value,0,1,4) instead and set the " + 
+           "MixxxControl to its return value.");
 }
 
 /* -------- ------------------------------------------------------
@@ -134,7 +138,9 @@
 // See full details here: http://mixxx.org/wiki/doku.php/midi_scripting#available_common_functions
 
 // ----------   Variables    ----------
-scratch.variables = { "time":0.0, "trackPos":0.0, "initialTrackPos":-1.0, "initialControlValue":0, "scratch":0.0, "prevControlValue":0, "wrapCount":0 };
+scratch.variables = { "time":0.0, "trackPos":0.0, "initialTrackPos":-1.0,
+                      "initialControlValue":0, "scratch":0.0,
+                      "prevControlValue":0, "wrapCount":0 };
 
 // ----------   Functions   ----------
 
@@ -146,19 +152,18 @@
    Input:   Currently-controlled Mixxx deck
    Output:  -
    -------- ------------------------------------------------------ */
-scratch.enable = function (currentDeck) {
+scratch.enable = function (currentDeck,newBehavior) {
     // Store scratch info at the point it was touched
     // Current position in seconds:
-    scratch.variables["initialTrackPos"] = scratch.variables["trackPos"] = engine.getValue("[Channel"+currentDeck+"]","playposition") * engine.getValue("[Channel"+currentDeck+"]","duration");
+    scratch.variables["initialTrackPos"] = scratch.variables["trackPos"] = engine.getValue("[Channel"+currentDeck+"]","visual_playposition") * engine.getValue("[Channel"+currentDeck+"]","duration");
     
     scratch.variables["time"] = new Date()/1000;   // Current time in seconds
+    if (newBehavior) engine.setValue("[Channel"+currentDeck+"]","scratch2_enable", 1);
     
-    // Stop the deck motion. This means we have to pause it if playing
+    // If the deck is playing, slow it to a stop
     if (engine.getValue("[Channel"+currentDeck+"]","play") > 0) {
-        scratch.variables["play"]=true;
-//         engine.setValue("[Channel"+currentDeck+"]","play",0);   // pause playback
+        // TODO: ramp down
     }
-    else scratch.variables["play"]=false;
     
 //     print("MIDI Script: Scratch initial: time=" + scratch.variables["time"] + "s, track=" + scratch.variables["trackPos"] + "s");
     return;
@@ -172,6 +177,10 @@
    Output:  -
    -------- ------------------------------------------------------ */
 scratch.disable = function (currentDeck) {
+    // If the deck is playing, ramp it up to the play speed
+    if (engine.getValue("[Channel"+currentDeck+"]","play") > 0) {
+        //TODO: ramp up
+    }
     // Reset the triggers
     scratch.variables["trackPos"] = 0.0;
     scratch.variables["initialTrackPos"] = -1.0;
@@ -181,8 +190,9 @@
     scratch.variables["time"] = 0.0;
     scratch.variables["scratch"] = 0.0;
 //     print("MIDI Script: Scratch values CLEARED");
-    engine.setValue("[Channel"+currentDeck+"]","scratch",0.0); // disable scratching
-    if (scratch.variables["play"]) engine.setValue("[Channel"+currentDeck+"]","play",1); // resume playback
+    engine.setValue("[Channel"+currentDeck+"]","scratch2_enable", 0);  // disable scratching
+    engine.setValue("[Channel"+currentDeck+"]","scratch2",0);
+    engine.setValue("[Channel"+currentDeck+"]","scratch",0);    // Deprecated
 }
 
 /* -------- ------------------------------------------------------
@@ -201,8 +211,13 @@
     // If the slider start value hasn't been set yet, set it
     if (scratch.variables["initialControlValue"] == 0) {
         scratch.variables["initialControlValue"] = sliderValue;
+        if (engine.getValue("[Channel"+currentDeck+"]","play") > 0) {
+            scratch.variables["scratch"] = 1;
+            engine.setValue("[Channel"+currentDeck+"]","scratch2", 1);
+        }
+//         engine.setValue("[Channel"+currentDeck+"]","scratch2_enable", 1);
 //         print("Initial slider="+scratch.variables["initialControlValue"]);
-        }
+    }
     return scratch.filter(currentDeck, sliderValue, revtime, alpha, beta);
 }
 
@@ -222,8 +237,13 @@
     // If the wheel start value hasn't been set yet, set it
     if (scratch.variables["initialControlValue"] == 0) {
         scratch.variables["initialControlValue"] = scratch.variables["prevControlValue"] = wheelValue;
+        if (engine.getValue("[Channel"+currentDeck+"]","play") > 0) {
+            scratch.variables["scratch"] = 1;
+            engine.setValue("[Channel"+currentDeck+"]","scratch2", 1);
+        }
+//         engine.setValue("[Channel"+currentDeck+"]","scratch2_enable", 1);
 //         print("Initial wheel="+scratch.variables["initialControlValue"]);
-        }
+    }
         
     // Take wrap around into account
     if (wheelValue>=0 && wheelValue<10 && scratch.variables["prevControlValue"]>117 && scratch.variables["prevControlValue"]<=127) scratch.variables["wrapCount"]+=1;
@@ -244,7 +264,7 @@
     // ideal position = (initial_p + (y - x) / 128 * 1.8)
     var ideal_p = scratch.variables["initialTrackPos"] + (controlValue - scratch.variables["initialControlValue"]) / 128 * revtime;
     
-    var currentTrackPos = engine.getValue("[Channel"+currentDeck+"]","playposition") * engine.getValue("[Channel"+currentDeck+"]","duration");
+    var currentTrackPos = engine.getValue("[Channel"+currentDeck+"]","visual_playposition") * engine.getValue("[Channel"+currentDeck+"]","duration");
     var newTime = new Date()/1000;
     var dt = newTime - scratch.variables["time"];
     scratch.variables["time"] = newTime;
@@ -259,13 +279,13 @@
     // scratch.variables["trackPos"] += rx * alpha;   // Don't need this result so why waste the CPU time?
     
     // v += rx * BETA / dt;
-    // scratch.variables["scratch"] += rx * (beta / dt);   // This doesn't work
+//     scratch.variables["scratch"] += rx * beta / dt;   // This doesn't work
     scratch.variables["scratch"] = rx * beta;
     
 //     print("MIDI Script: Ideal position="+ideal_p+", Predicted position="+predicted_p + ", New scratch val=" + scratch.variables["scratch"]);
     
 //     var newPos = scratch.variables["trackPos"]/engine.getValue("[Channel"+currentDeck+"]","duration");
-//     engine.setValue("[Channel"+currentDeck+"]","playposition",newPos);
+//     engine.setValue("[Channel"+currentDeck+"]","visual_playposition",newPos);
 //     engine.setValue("[Channel"+currentDeck+"]","scratch",scratch.variables["scratch"]);
 
     return scratch.variables["scratch"];

=== modified file 'mixxx/src/controlvaluedelegate.cpp'
--- mixxx/src/controlvaluedelegate.cpp	2009-09-01 15:33:21 +0000
+++ mixxx/src/controlvaluedelegate.cpp	2010-04-29 07:06:29 +0000
@@ -47,6 +47,7 @@
         m_channelControlValues.append("rate_perm_up_small");
         m_channelControlValues.append("rateRange");
         m_channelControlValues.append("scratch");
+        m_channelControlValues.append("scratch_enable");
         m_channelControlValues.append("transform");
         m_channelControlValues.append("volume");
         m_channelControlValues.append("wheel");

=== modified file 'mixxx/src/engine/ratecontrol.cpp'
--- mixxx/src/engine/ratecontrol.cpp	2010-03-20 21:14:06 +0000
+++ mixxx/src/engine/ratecontrol.cpp	2010-04-29 07:06:29 +0000
@@ -116,7 +116,13 @@
     // Scratch controller, this is an accumulator which is useful for
     // controllers that return individiual +1 or -1s, these get added up and
     // cleared when we read
-    m_pScratch = new ControlTTRotary(ConfigKey(_group, "scratch"));
+    m_pScratch = new ControlTTRotary(ConfigKey(_group, "scratch2"));
+    m_pOldScratch = new ControlTTRotary(ConfigKey(_group, "scratch"));  // Deprecated
+    
+    // Scratch enable toggle
+    m_pScratchToggle = new ControlPushButton(ConfigKey(_group, "scratch2_enable"));
+    m_pScratchToggle->set(0);
+    m_pScratchToggle->setToggleButton(true);
 
     m_pJog = new ControlObject(ConfigKey(_group, "jog"));
     m_pJogFilter = new Rotary();
@@ -156,6 +162,7 @@
 
     delete m_pWheel;
     delete m_pScratch;
+    delete m_pOldScratch;
     delete m_pJog;
     delete m_pJogFilter;
 }
@@ -309,20 +316,6 @@
         m_pRateDir->get();
 }
 
-double RateControl::getScratchFactor() {
-    double scratchFactor = m_pScratch->get();
-    if(!isnan(scratchFactor) && scratchFactor != 0.0f) {
-        if (scratchFactor < 0.) {
-            scratchFactor = scratchFactor - 1.0f;
-        } else if (scratchFactor > 0.) {
-            scratchFactor = scratchFactor + 1.0f;
-        }
-    } else {
-        scratchFactor = 1.0f;
-    }
-    return scratchFactor;
-}
-
 double RateControl::getWheelFactor() {
     // Calculate wheel (experimental formula)
     return 40 * m_pWheel->get();
@@ -350,17 +343,27 @@
 double RateControl::calculateRate(double baserate, bool paused) {
     double rate = 0.0;
     double wheelFactor = getWheelFactor();
-    double scratchFactor = getScratchFactor();
     double jogFactor = getJogFactor();
     bool searching = m_pRateSearch->get() != 0.;
+    bool scratchEnable = m_pScratchToggle->get() != 0;
+    double scratchFactor = m_pScratch->get();
+    double oldScratchFactor = m_pOldScratch->get(); // Deprecated
+    // Don't trust values from m_pScratch
+    if(isnan(scratchFactor)) {
+        scratchFactor = 0.0;
+    }
+    if(isnan(oldScratchFactor)) {
+        oldScratchFactor = 0.0;
+    }
 
     if (searching) {
         // If searching is in progress, it overrides the playback rate.
         rate = m_pRateSearch->get();
     } else if (paused) {
         // Stopped. Wheel, jog and scratch controller all scrub through audio.
-        // Scratch is centered around 1.0, so subtract 1.0
-        rate = scratchFactor - 1.0f + jogFactor + wheelFactor/10.;
+        // New scratch behavior overrides old
+        if (scratchEnable) rate = scratchFactor + jogFactor + wheelFactor/10.;
+        else rate = oldScratchFactor + jogFactor + wheelFactor/10.; // Just remove oldScratchFactor in future
     } else {
         // The buffer is playing, so calculate the buffer rate.
 
@@ -372,7 +375,18 @@
 
         rate = 1. + getRawRate() + getTempRate();
         rate += wheelFactor/10.;
-        rate *= scratchFactor;
+
+        // New scratch behavior - overrides playback speed (and old behavior)
+        if (scratchEnable) rate *= scratchFactor;
+        // Deprecated old scratch behavior
+        else {
+            if (oldScratchFactor < 0.) {
+                rate *= (oldScratchFactor-1.);                
+            } else if (oldScratchFactor > 0.) {
+                rate *= (oldScratchFactor+1.);
+            }
+        }
+        
         rate += jogFactor;
 
         // If we are reversing, flip the rate.

=== modified file 'mixxx/src/engine/ratecontrol.h'
--- mixxx/src/engine/ratecontrol.h	2010-01-05 03:57:34 +0000
+++ mixxx/src/engine/ratecontrol.h	2010-04-29 07:06:29 +0000
@@ -66,7 +66,6 @@
 private:
     double getJogFactor();
     double getWheelFactor();
-    double getScratchFactor();
     
     /** Set rate change of the temporary pitch rate */
     void setRateTemp(double v);
@@ -95,6 +94,8 @@
 
     ControlTTRotary* m_pWheel;
     ControlTTRotary* m_pScratch;
+    ControlTTRotary* m_pOldScratch;
+    ControlPushButton* m_pScratchToggle;
     ControlObject* m_pJog;
     Rotary* m_pJogFilter;