@Override
public boolean onDown(MotionEvent event) {
scrolling = false;
synchronized (GlobalData.audioScene) {
// determine transformed coordinate of touch point
touchPoint[0] = event.getX();
touchPoint[1] = event.getY();
inverseViewportTransformation.mapPoints(touchPoint);
GlobalData.audioScene.inverseMapPoint(touchPoint);
// try to find nearest sound source
lastTouchSoundSource = GlobalData.audioScene.getNearestSoundSource(touchPoint);
if (lastTouchSoundSource != null) {
// get distance (touch point to source) in pixels
selectionOffset[0] = lastTouchSoundSource.getX();
selectionOffset[1] = lastTouchSoundSource.getY();
GlobalData.audioScene.mapPoint(selectionOffset);
viewportTransformation.mapPoints(selectionOffset);
selectionOffset[0] -= event.getX();
selectionOffset[1] -= event.getY();
float distance =
FloatMath.sqrt(
selectionOffset[0] * selectionOffset[0] + selectionOffset[1] * selectionOffset[1]);
// select source?
if (distance > SOURCE_SELECT_RADIUS) {
lastTouchSoundSource = null;
}
}
}
return true;
}
public float[][] getSceneBounds(Matrix viewportTransformation) {
float[] point = {0.0f, 0.0f};
// map reference point to screen coordinate system
viewportTransformation.mapPoints(point);
// set min/max to reference position
float[][] minMaxXY = {
{point[0], point[1]}, {point[0], point[1]}
}; // two points: minXY and maxXY
synchronized (GlobalData.audioScene) {
int numSources = GlobalData.audioScene.getNumSoundSources();
SoundSource s = null;
for (int i = 0; i < numSources; i++) {
s = GlobalData.audioScene.getSoundSource(i);
point[0] = s.getX();
point[1] = s.getY();
// map to reference coordinate system
GlobalData.audioScene.mapPoint(point);
viewportTransformation.mapPoints(point);
// check if point lies outwards current bounds
if (point[0] < minMaxXY[0][0]) minMaxXY[0][0] = point[0];
if (point[0] > minMaxXY[1][0]) minMaxXY[1][0] = point[0];
if (point[1] < minMaxXY[0][1]) minMaxXY[0][1] = point[1];
if (point[1] > minMaxXY[1][1]) minMaxXY[1][1] = point[1];
}
}
return minMaxXY;
}
