Add 'Slice' effect.

src/js/HuesCanvas.js

@@ -57,6 +57,13 @@ class HuesCanvas {
         this.xBlur = false;
         this.yBlur = false;
         
+        this.sliceAvgSegments = 15;
+        this.sliceCount = 0;
+        this.sliceSegments = [];
+        this.sliceDistances = [];
+        this.sliceDistance = 0;
+        this.sliceStart = 0;
+        
         // trippy mode
         this.trippyStart = [0, 0]; // x, y
         this.trippyRadii = [0, 0]; // x, y
@@ -166,6 +173,13 @@ class HuesCanvas {
             } else {
                 offset = width/2 - drawWidth/2;
             }
+            
+            if(this.sliceStart) {
+                bitmap = this.drawSlice(bitmap, drawWidth, drawHeight, width, height);
+                drawWidth = width;
+                drawHeight = height;
+            }
+            
             if(this.xBlur || this.yBlur) {
                 this.drawBlur(bitmap, offset, drawWidth, drawHeight);
             }else {
@@ -203,6 +217,27 @@ class HuesCanvas {
         }
     }
 
+    drawSlice(bitmap, drawWidth, drawHeight, width, height) {
+        this.offContext.clearRect(0,0,width,height);
+        
+        let bitmapoffset = 0;
+        let drawOffset = 0;
+        for(let i = 0; i < this.sliceCount; i++) {
+            let segment = this.sliceSegments[i];
+            let segmentBitmapHeight = Math.round(segment * bitmap.height);
+            let segmentDrawHeight = Math.round(segment * drawHeight);
+            this.offContext.drawImage(bitmap,
+                                      0 , bitmapoffset, // subsection x, y
+                                      bitmap.width, segmentBitmapHeight, // sub w/h
+                                      this.sliceDistances[i] * this.sliceDistance, drawOffset, // drawn section x, y
+                                      drawWidth, segmentDrawHeight); // drawn w/h
+            bitmapoffset += segmentBitmapHeight;
+            drawOffset += segmentDrawHeight;
+        }
+        
+        return this.offCanvas;
+    }
+    
     drawBlur(bitmap, offset, drawWidth, drawHeight) {
         this.context.globalAlpha = this.blurAlpha;
         if(this.xBlur) {
@@ -310,6 +345,29 @@ class HuesCanvas {
             else
                 this.core.blurUpdated(0, dist);
         }
+        if(this.sliceStart) {
+            let transitionPercent = 0.8;
+            let delta;
+            let now = this.audio.currentTime;
+            if(now < this.sliceRampUp) {
+                delta = this.sliceRampUp - now;
+                this.sliceDistance = (1-(delta / this.sliceTransitionTime)) * transitionPercent;
+            } else if(now < this.sliceRampDown) {
+                delta = this.sliceRampDown - now;
+                let longTransition = this.sliceRampDown - this.sliceRampUp;
+                this.sliceDistance = transitionPercent + ((1-(delta / longTransition)) * (1-transitionPercent));
+            } else {
+                let endEffect = this.sliceRampDown + this.sliceTransitionTime;
+                if(now > endEffect) {
+                    this.sliceStart = 0;
+                    this.sliceDistance = 0;
+                } else {
+                    delta = endEffect - now;
+                    this.sliceDistance = delta / this.sliceTransitionTime;
+                }
+            }
+            this.needsRedraw = true;
+        }
         if(this.trippyStart[0] || this.trippyStart[1]) {
             for(let i = 0; i < 2; i++) {
                 this.trippyRadii[i] = Math.floor((this.audio.currentTime - this.trippyStart[i]) * this.trippyRadius) * 2;
@@ -498,6 +556,40 @@ class HuesCanvas {
         this.trippyOn = saveTrippy;
     }
     
+    doSlice(beatLength, beatCount) {
+        let transitionTime = Math.min(0.06, beatLength);
+        
+        this.sliceStart = this.audio.currentTime;
+        this.sliceRampUp = this.sliceStart + transitionTime;
+        this.sliceRampDown = this.sliceStart + (beatLength * beatCount) - transitionTime;
+        this.sliceTransitionTime = transitionTime;
+        
+        this.generateSliceSegments();
+        this.needsRedraw = true;
+    }
+    
+    generateSliceSegments() {
+        let even = 1.0 / this.sliceAvgSegments;
+        let spread = even / 2;
+        let total = 0;
+        let i;
+        for(i = 0; ; i++) {
+            let deviation = Math.random() * spread*2 - spread;
+            let rando = even + deviation;
+            this.sliceSegments[i] = rando;
+            total += this.sliceSegments[i];
+            
+            this.sliceDistances[i] = Math.random() * this.blurAmount - this.blurAmount/2;
+            
+            if(total > 1.0) {
+                this.sliceSegments[i] -= total - 1.0;
+                break;
+            }
+        }
+        this.sliceCount = i+1;
+        
+    }
+
     setBlurDecay(decay) {
         this.blurDecay = {"slow" : 7.8, "medium" : 14.1, "fast" : 20.8, "faster!" : 28.7}[decay];
     }

src/js/HuesCore.js

@@ -766,20 +766,13 @@ class HuesCore {
                 }
                 /* falls through */
             case '~':
-                // case: fade in build, not in rhythm. Must max out fade timer.
+                this.renderer.doColourFade(this.timeToNextBeat());
-                let maxSearch = this.currentSong.rhythm.length;
-                if(this.beatIndex < 0) {
-                    maxSearch -= this.beatIndex;
-                }
-                let fadeLen;
-                for (fadeLen = 1; fadeLen <= maxSearch; fadeLen++) {
-                    if (this.getBeat(fadeLen + this.beatIndex) != ".") {
-                        break;
-                    }
-                }
-                this.renderer.doColourFade((fadeLen * this.getBeatLength()) / this.soundManager.playbackRate);
                 this.randomColour(true);
                 break;
+            case 'S':
+            case 's':
+                this.renderer.doSlice(this.getBeatLength(), this.charsToNextBeat());
+                break;
             case 'I':
                 if (this.isFullAuto) {
                     this.randomImage();
@@ -792,7 +785,7 @@ class HuesCore {
             if ([".", "+", "|", "¤"].indexOf(beat) == -1) {
                 this.renderer.clearBlackout();
             }
-            if([".", "+", "¤", ":", "*", "X", "O", "~", "=", "i", "I"].indexOf(beat) == -1) {
+            if([".", "+", "¤", ":", "*", "X", "O", "~", "=", "i", "I", "s"].indexOf(beat) == -1) {
                 this.randomColour();
                 if (this.isFullAuto) {
                     this.randomImage();
@@ -800,6 +793,26 @@ class HuesCore {
         }
     }
     
+    
+    charsToNextBeat() {
+        // case: fade in build, not in rhythm. Must max out fade timer.
+        let maxSearch = this.currentSong.rhythm.length;
+        if(this.beatIndex < 0) {
+            maxSearch -= this.beatIndex;
+        }
+        let nextBeat;
+        for (nextBeat = 1; nextBeat <= maxSearch; nextBeat++) {
+            if (this.getBeat(nextBeat + this.beatIndex) != ".") {
+                break;
+            }
+        }
+        return nextBeat;
+    }
+    
+    timeToNextBeat() {
+        return (this.charsToNextBeat() * this.getBeatLength()) / this.soundManager.playbackRate;
+    }
+
     getBeatString(length) {
         length = length ? length : 256;
 

src/js/HuesInfo.js

@@ -41,7 +41,9 @@ const beatGlossary = [
     "~ Fade color",
     "= Fade and change image",
     "i Invert all colours",
-    "I Invert & change image"
+    "I Invert & change image",
+    "s Slice",
+    "S Slice and change image"
 ];
 
 const shortcuts = [