How to fill with color the area between lines in android?

Question

Android

There is code that creates two curved lines that extend from the left to the top. How can you fill with the right color the area that has formed between them, taking into account the fact that the lines can move?

public class DrawView extends View {

Paint paint;
Path path1 = new Path();
Path path2 = new Path();

public DrawView(Context context) {
    super(context);
    init();
}

public DrawView(Context context, AttributeSet attrs) {
    super(context, attrs);
    init();
}

public DrawView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    init();
}

private void init() {
    paint = new Paint();
    paint.setStyle(Paint.Style.STROKE);
}

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    path1.reset();
    path2.reset();

    paint.setColor(Color.RED);
    paint.setStrokeWidth(3);

    path1.moveTo(0, 750);
    path2.moveTo(0, 900);

    path1.cubicTo(185, 250, 599, 177, 585, 0);
    path2.cubicTo(350, 250, 750, 177, 900, 0);

    canvas.drawPath(path1, paint);
    canvas.drawPath(path2, paint);

 }
}

Answer 1

search for two points horizontally, paint with horizontal lines
to speed up - own implementation of a cubic spline, point caching