Question

Background: Using Canvas, Paint and Path objects I draw several geometries on the canvas, mostly polygons and circles. They fill most of the Android screen.

Question: With Mathematica I can ‘fast-copy’ Graphics using Translate ( in x and y direction ), after which the resulting image is automatically zoomed out such that all copies are visible. ( For example. Draw a square that fills the entire screen, copy it using (2,2) and four squares appear. ) The premise is that copying is a faster operation. – Is a similar operation possible on Android?

Answer 1

There’s nothing as convenient as that, but to achieve the effect you can draw directly to a Bitmap and re-use it – scaling and translating it yourself.

public void onDraw(Canvas canvas) {
    Bitmap bmp = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas bmpCanvas = new Canvas(bmp);

    // draw into bmpCanvas
    // ...

    // draw bitmap using
    // public void drawBitmap (Bitmap bitmap, Rect src, RectF dst, Paint paint)
    canvas.drawBitmap(bmp, ...);