Merge pull request #60 from JacobSeto/ben-programming

Create SoundController.java

core/src/edu/cornell/gdiac/rabbeat/SoundController.java

@@ -0,0 +1,116 @@
+package edu.cornell.gdiac.rabbeat;
+
+import com.badlogic.gdx.audio.Music;
+
+public class SoundController {
+
+    private Music synthTrack;
+    private Music jazzTrack;
+
+    private Genre currentGenre;
+
+    /**
+     * Set this to true to make genre switches instantaneous / in one frame.
+     * Set this to false to make genre switches gradual / over several frames.
+     */
+    private static final boolean USE_INSTANT_SWITCH = true;
+
+    /**
+     * The length of time in milliseconds that a gradual genre switch takes.
+     * If instant switch is enabled, this value doesn't matter.
+     */
+    private static final float GRADUAL_SWITCH_DURATION = 1000f;
+    private boolean currentlyUpdating;
+    private int currentUpdateFrame = 0;
+
+    public SoundController() {
+        currentGenre = Genre.SYNTH;
+        currentlyUpdating = false;
+    }
+
+    public void setSynthTrack(Music track) { synthTrack = track;}
+
+    public void setJazzTrack(Music track) { jazzTrack = track;}
+
+    /**
+     * This method sets the genre AND sets the currentlyUpdating flag to true.
+     * update() then uses that flag to gradually or instantly change the music.
+     * It also resets any ongoing gradual shifts, which is why it might look backwards.
+     * If instant shifts are enabled, the volumes set here will be immediately overridden.
+     * @param genre
+     */
+    /*
+    TODO: Maybe change behavior of quick genre switches when each switch is gradual.
+     * Currently, if a switch happens twice in quick succession,
+     * the first gradual switch will be replaced with an instantaneous switch to allow
+     * the second one to happen gradually.
+     */
+
+    public void setGenre(Genre genre) {
+        currentGenre = genre;
+        currentlyUpdating = true;
+        currentUpdateFrame = 0;
+
+        if (USE_INSTANT_SWITCH) return;
+
+        // Otherwise, skip to the end of the previous genre switch
+
+        // The genre just changed from synth to jazz
+        if (genre == Genre.JAZZ) {
+            jazzTrack.setVolume(0);
+            synthTrack.setVolume(1);
+        }
+        // The genre just changed from jazz to synth
+        else {
+            synthTrack.setVolume(0);
+            jazzTrack.setVolume(1);
+        }
+    }
+
+    public void update() {
+        if (!currentlyUpdating) return;
+        if (USE_INSTANT_SWITCH) {
+            switchMusicGenreInstant();
+        }
+        else {
+
+            // Convert from milliseconds to frames
+            switchMusicGenreGradual(GRADUAL_SWITCH_DURATION * 60f / 1000f);
+        }
+    }
+
+    /**
+     * Immediately switches from synth to jazz, or vice versa.
+     * The switch has no delay.
+     */
+    public void switchMusicGenreInstant() {
+        synthTrack.setVolume(1 - synthTrack.getVolume());
+        jazzTrack.setVolume(1 - jazzTrack.getVolume());
+        currentlyUpdating = false;
+    }
+
+    /**
+     * Switches from synth to jazz in a given number of frames.
+     * Each method call makes a small adjustment to the volume of both tracks.
+     * @param frameCount The number of frames between the start of the transition and the end.
+     */
+
+    public void switchMusicGenreGradual(float frameCount) {
+        currentUpdateFrame++;
+        // The genre just switched from synth to jazz
+        if (currentGenre == Genre.JAZZ) {
+            jazzTrack.setVolume(jazzTrack.getVolume() + 1/frameCount);
+            synthTrack.setVolume(synthTrack.getVolume() - 1/frameCount);
+        }
+
+        // The genre just switched from jazz to synth
+        else {
+            synthTrack.setVolume(synthTrack.getVolume() + 1/frameCount);
+            jazzTrack.setVolume(jazzTrack.getVolume() - 1/frameCount);
+        }
+        if (currentUpdateFrame > frameCount) {
+            currentUpdateFrame = 0;
+            currentlyUpdating = false;
+        }
+    }
+}