On Wed, 9 Apr 2025 14:42:05 GMT, Maxim Kartashev <mkartas...@openjdk.org> wrote:
> The pixels that cairo produces for GTK LaF to draw on a Swing component have > their alpha components pre-multiplied as per [the > documentation](https://www.cairographics.org/manual/cairo-Image-Surfaces.html?spm=a2ty_o01.29997173.0.0.540ac921z2EebT#cairo-format-t): >> Pre-multiplied alpha is used. (That is, 50% transparent red is 0x80800000, >> not 0x80ff0000.) > > The BufferedImage created from those pixels, however, has its constructor's > argument for `isRasterPremultiplied` set to `false` in > `GTKEngine.finishPainting()`. This commit corrects that. > > In addition, since at least some "native" graphics color models also use > pre-multiplied alpha (ex.: `GLXGraphicsConfig.getColorModel()`), > `COLOR_MODELS` were modified to take advantage of that and avoid unnecessary > re-calculations of image's pixels. src/java.desktop/share/classes/com/sun/java/swing/plaf/gtk/GTKEngine.java line 618: > 616: int index = transparency - 1; > 617: if (COLOR_MODELS[index] == null) { > 618: COLOR_MODELS[index] = > GraphicsEnvironment.getLocalGraphicsEnvironment() How will it work if the configuration changes at runtime? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/24551#discussion_r2038750301
