I see the 'bug' is still there in the final HC SDK. It is not by design is it?
On Jan 31, 5:39 pm, webmonkey <[email protected]> wrote: > Just as I suspected there is a bug in Honeycomb that allows me to work > around not having a setHasAlpha function. > > Using the new inMutable option in BitmapFactory.Options I can decode a > dummy JPG and because it is a JPG the opaque hint is set. Now whatever > set function you call on the bitmap, the opaque flag is never cleared > and so it optimizes the drawing. It is rather silly though that I have > to do it this way. > > I also wonder how the Android team is going to fix the actual "bug" in > Honeycomb. There are four ways as I see it: > > 1) When inMutable is set it always clears the opaque hint. This would > be dumb because it assumes the worst case scenario. > 2) For every set function check if it has transparent values so it can > clear the opaque flag. Lots of work and not very fast > 3) Add a XRGB_8888 Config. Not sure what kind of work is involved > here. > 4) Make the setHasAlpha public. This would be the easiest > solution :-) > > On Jan 25, 10:57 pm,webmonkey<[email protected]> wrote: > > > Hi Romain > > > Looking further into the Android source code when you create a 32-bit > > color bitmap the system always assumes you have alpha and there is no > > way to turn it off. Only when you load a JPEG or something does the > > system set the flag to ignore it. > > > That is an unnecessary performance penalty that can easily be avoided. > > For Honeycomb could you please make the setHasAlpha public or provide > > an XRGB_8888 config. For the upcoming tablets we are going to draw > > even more and bigger bitmaps. > > > On Jan 24, 10:01 pm,webmonkey<[email protected]> wrote: > > > > But that seems to be the only way to tell the system that it can > > > ignore the alpha channel. Bitmap.hasAlpha() just returns the flag. > > > > I am updating the bitmap a lot with copyPixelsFromBuffer so how do I > > > tell the system that it can ignore the alpha channel? > > > > On Jan 24, 9:49 pm, Romain Guy <[email protected]> wrote: > > > > > No you cannot. Methods marked @hide are not part of the public API. > > > > They are > > > > not present in ADT's android.jar so you cannot compile against it. We > > > > also > > > > might rename or remove such APIs at any point in the future. > > > > > On Mon, Jan 24, 2011 at 12:42 PM,webmonkey<[email protected]> wrote: > > > > > Ah thanks, I just checked the Android source and there is the > > > > > following function > > > > > > public void setHasAlpha(boolean hasAlpha) { > > > > > nativeSetHasAlpha(mNativeBitmap, hasAlpha); > > > > > } > > > > > > But it is set to @hide so it is not in the docs, can we use this > > > > > function? > > > > > > On Jan 24, 6:14 pm, Romain Guy <[email protected]> wrote: > > > > > > The system can detect when a ARGB_8888 bitmap is opaque (see > > > > > > Bitmap.hasAlpha()). > > > > > > > On Mon, Jan 24, 2011 at 8:26 AM,webmonkey<[email protected]> > > > > > wrote: > > > > > > > Now that Gingerbread has moved to 32-bit windows is there a way to > > > > > > > create a 32-bit bitmap without alpha to improve drawing > > > > > > > performance of > > > > > > > opaque bitmaps? > > > > > > > > Something like Bitmap.createBitmap( 512, 512, > > > > > > > Bitmap.Config.XRGB_8888 ) > > > > > > > > Or does the system somehow detect that the bitmap is opaque? > > > > > > > > -- > > > > > > > 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]<android-developers%2Bunsubs > > > > > > > [email protected]><android-developers%2Bunsubs > > > > > [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] > > > > > > > Note: please don't send private questions to me, as I don't have > > > > > > time to > > > > > > provide private support. All such questions should be posted on > > > > > > public > > > > > > forums, where I and others can see and answer them > > > > > > -- > > > > > 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]<android-developers%2Bunsubs > > > > > [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] > > > > > Note: please don't send private questions to me, as I don't have time to > > > > provide private support. All such questions should be posted on public > > > > forums, where I and others can see and answer them > > -- 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
