Until 4.2 the hardware accelerated rendering pipeline would render circles as a texture using the radius you specify in the drawCircle() call. It would then scale the texture based on the Canvas transform. In this case you are stretching a picture of a circule that's 1px large, which is why you are getting a rectangle. Instead of using Canvas.scale(), set the radius you want directly. Note that we lifted this limitation in 4.2.
On Fri, Jun 21, 2013 at 9:32 AM, Leith Bade <[email protected]>wrote: > I have been banging my head for a while trying to figure out why my custom > view was not drawing properly until I tried turning off hardware > acceleration. > > It is to do with canvas.drawCircle. It is drawn in solid blue at about > 300px radius. > > I also use canvas.drawText and that works fine under hardware acceleration. > > The only thing I can think of is that I a using an unsymmetrical > canvas.scale... > > Here is my code: > // Called to redraw the map > @Override > protected void onDraw(Canvas canvas) { > // Check if we are in Eclipse UI editor > if (isInEditMode()) { > return; > } > // Save the canvas' transforms for unscaled UI elements > canvas.save(); > // Place the map offset in centre of screen > canvas.translate(getWidth() / 2, getHeight() / 2); > // Zoom the map > canvas.scale((float) (-1.0 / mMapController.getMapMetresPerPixelX()), > (float) (-1.0 / mMapController.getMapMetresPerPixelY())); > // Pan the map > canvas.translate((float) mMapController.getMapCentreX(), (float) > mMapController.getMapCentreY()); > // Draw a circle > canvas.drawCircle(0.0f, 0.0f, 0.01f, mCirclePaint); > // Restore the canvas' transforms for unscaled UI elements > canvas.restore(); > // Draw the map centre coordinated and scale in top left > canvas.drawText("Centre Coord: (" + String.format("%.4f", > mMapController.getMapCentreX()) + ", " + String.format("%.4f", > mMapController.getMapCentreY()) + ")", 16.0f * mDisplayMetrics.density, > 36.0f * mDisplayMetrics.scaledDensity, mCoordPaint); > canvas.drawText("Scale:" + String.format("%.4f", > mMapController.getMapScale()), 16.0f * mDisplayMetrics.density, 54.0f * > mDisplayMetrics.scaledDensity, mCoordPaint); > } > > The values of the various variables from the debugger: > isInEditMode() = false > getWidth() = 1080 > getHeight() = 1701 > getMapMetresPerPixelX() = 5.37037039426811E-5 > getMapMetresPerPixelY() = -5.364583215838397E-5 > getMapCentreX() = 0.0 > getMapCentreY() = 0.0 > getMapScale() = 1.0 > mCirclePaint = new Paint(Paint.ANTI_ALIAS_FLAG); > mCirclePaint.setColor(Color.BLUE); > mCoordPaint = new Paint(Paint.ANTI_ALIAS_FLAG); > mCoordPaint.setColor(Color.BLACK); > mCoordPaint.setTextSize(18.0f * mDisplayMetrics.scaledDensity); > mDisplayMetrics.density = 3.0 > mDisplayMettrics.scaledDensity = 3.0 > > I hope that helps figure it out. > > I am going to try on the emulator with 4.2 too see what happens. > > Leith > > -- > -- > 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 > --- > You received this message because you are subscribed to the Google Groups > "Android Developers" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- 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 --- You received this message because you are subscribed to the Google Groups "Android Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
