Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
374 views
in Technique[技术] by (71.8m points)

java - Android: How to get the area size of a drawn path?

My problem is to measure the surface area of a path.
I generate a random Path and draw it on a canvas. After touching on this closen path, i want to get the area size of this drawn path.

How can i get the real area size of this path?

The pathes (shapes) looks like this here:
link to the image

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

I found a solution. I generate a Region from the path and use a RegionIterator to get Rects inside the Region. With this Rects i can calculate the whole area of the path.

private void calculateArea(Region region) {

        RegionIterator regionIterator = new RegionIterator(region);

        int size = 0; // amount of Rects
        float area = 0; // units of area

        Rect tmpRect= new Rect(); 

        while (regionIterator.next(tmpRect)) {
            size++;
            area += tmpRect.width() * tmpRect.height();
        }

        log.d("Rect amount=" + size);
        log.d("Area Size / units of area=" + area);
}

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...