Circles are currently drawn as texture, so every time you create acircle with a different radius, the OpenGL pipeline generates a newtexture. It should however not run out of memory since the circlestextures are kept in a fixed size cache. You should callsetLayerType(View.LAYER_TYPE_SOFTWARE, null) on your View to workaround this problem.
Update: I checked and this out of memory error is a bug in 3.2 that we fixed in 4.0. On Thu, Dec 15, 2011 at 4:31 PM, Christopher Van Kirk <[email protected]> wrote: > How many times is 'a few'? > > On 12/15/2011 12:45 AM, Christopher Golden wrote: >> >> In the course of developing an Android application, I'm finding a need >> to draw several unfilled concentric circles centered on an arbitrary >> point, enough that some of them are only partly visible on the >> display. However, this does not appear to work with hardware >> acceleration. My test rig is a stock Samsung Galaxy Tab 10.1 running >> Android 3.2. >> >> The following code comes from a test subclass of View I wrote to >> isolate the issue: >> >> private Paint paint = new Paint(); >> >> private int count = 0; >> >> private static final int[] COLORS = { 0xffff0000, 0xff00ff00, >> 0xff0000ff, 0xffff00ff }; >> >> public TestCircles(Context context) { >> super(context); >> paint.setStrokeWidth(1.0f); >> paint.setStyle(Paint.Style.STROKE); >> } >> >> public TestCircles(Context context, AttributeSet attributes) { >> super(context, attributes); >> paint.setStrokeWidth(1.0f); >> paint.setStyle(Paint.Style.STROKE); >> } >> >> public boolean onTouchEvent(MotionEvent e) { >> if (e.getAction() == MotionEvent.ACTION_DOWN) >> invalidate(); >> return true; >> } >> >> protected void onDraw(Canvas canvas) { >> >> // Pick the color to use, cycling through the colors list >> repeatedly, so that we can >> // see the different redraws. >> paint.setColor(COLORS[count++]); >> count %= COLORS.length; >> >> // Set up the parameters for the circles; they will be centered at >> the center of the >> // canvas and have a maximum radius equal to the distance between >> a canvas corner >> // point and its center. >> final float x = canvas.getWidth() / 2f; >> final float y = canvas.getHeight() / 2f; >> final float maxRadius = (float) Math.sqrt((x * x) + (y * y)); >> >> // Paint the rings until the rings are too large to see. >> for (float radius = 20; radius< maxRadius; >> radius += 20) >> canvas.drawCircle(x, y, radius, paint); >> } >> >> I am running TestCircles as the only View in an Activity, laying it >> out to fill the available width and height (i.e. it is nearly full- >> screen). I can tap on the display (triggering redraws) only a few >> times before the redraws no longer occur (i.e. the circles' color >> doesn't change). Actually, the onDraw() code is still running in >> response to each tap -- as proven with diagnostic messages -- but >> nothing changes onscreen. >> >> When onDraw() first starts to fail to redraw, the debug log includes >> the following entry, once for every call to onDraw(): >> >> E/OpenGLRenderer(21867): OpenGLRenderer is out of memory! >> >> If I turn off hardware acceleration in the manifest, these problems go >> away -- not surprising since clearly OpenGL is having problems -- and >> actually it is a good deal faster than the few times it actually works >> under hardware acceleration. >> >> My questions are: >> >> First, am I misusing Canvas, or is this a bug, or both? Is Android >> allocating large bitmaps under the hood to draw these circles? It >> doesn't seem like this should be this challenging to OpenGL, but I'm >> new to hardware accelerated app development. >> >> Second, what's a good alternative way to draw large unfilled circles >> that have portions extending out of the clipping region of the Canvas? >> Losing hardware acceleration is not an option. >> >> Thanks in advance... >> > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en -- Romain Guy Android framework engineer [email protected] -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
