lib/android: demultiply pixel data from alpha value on request only

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/lib/android/load_image.nit b/lib/android/load_image.nit
index bc3cb02..cea5502 100644 (file)
--- a/lib/android/load_image.nit
+++ b/lib/android/load_image.nit
@@ -31,8 +31,11 @@ redef extern class NativeBitmap
        # Copy the pixel data into a new `CByteArray`
        #
        # If `pad_to_pow2` the new buffer contains artificial pixels used to make
-       # the width and the height powers of 2 for compatibility with OpenGL.
-       fun copy_pixels(pad_to_pow2: nullable Bool): CByteArray
+       # the width and the height powers of 2 for compatibility with older OpenGL.
+       #
+       # If `unmultiply`, extra work is done to revert the multiplication of color
+       # values per the alpha channel applied by the Android system.
+       fun copy_pixels(pad_to_pow2, unmultiply: nullable Bool): CByteArray
        do
                var height = height
                var row_bytes = row_bytes
@@ -49,7 +52,7 @@ redef extern class NativeBitmap
                var java_buf = buf.to_java_nio_buffer
                copy_pixels_to_buffer java_buf
 
-               if has_alpha then buf.native_array.unmultiply(width, height)
+               if has_alpha and unmultiply == true then buf.native_array.unmultiply(width, height)
 
                if pad_to_pow2 == true then
                        for r in [height-1..0[.step(-1) do

diff --git a/lib/mnit/android/android_assets.nit b/lib/mnit/android/android_assets.nit
index 06af952..e30db6d 100644 (file)
--- a/lib/mnit/android/android_assets.nit
+++ b/lib/mnit/android/android_assets.nit
@@ -67,7 +67,7 @@ redef class App
                        jni_env.push_local_frame 4
 
                        var bmp = asset_manager.bitmap(path)
-                       var buf = bmp.copy_pixels(true)
+                       var buf = bmp.copy_pixels(true, true)
                        var w2 = bmp.width.next_pow(2)
                        var h2 = bmp.height.next_pow(2)
                        var png = new Opengles1Image.from_data(buf.native_array, bmp.width, bmp.height, w2, h2, true)