On Fri, Sep 20, 2019 at 9:20 AM Maxime Ripard <mripard@xxxxxxxxxx> wrote: > > On Thu, Sep 19, 2019 at 08:53:10PM +0200, Jernej Škrabec wrote: > > Dne sreda, 18. september 2019 ob 13:05:41 CEST je > > roman.stratiienko@xxxxxxxxxxxxxxx napisal(a): > > > From: Roman Stratiienko <roman.stratiienko@xxxxxxxxxxxxxxx> > > > > > > According to Allwinner DE2.0 Specification REV 1.0, vi layer supports the > > > following pixel formats: ABGR_8888, ARGB_8888, BGRA_8888, RGBA_8888 > > > > It's true that DE2 VI layers support those formats, but it wouldn't change > > anything because alpha blending is not supported by those planes. These > > formats were deliberately left out because their counterparts without alpha > > exist, for example ABGR8888 <-> XBGR8888. It would also confuse user, which > > would expect that alpha blending works if format with alpha channel is > > selected. > > I'm not too familiar with the DE2 code, but why is alpha not working > if the VI planes support formats with alpha? Good question. It mentioned in the datasheet https://linux-sunxi.org/images/7/7b/Allwinner_DE2.0_Spec_V1.0.pdf on page 95: "All ui layers' alpha is useless" And my experiments proves it. My assumption that vi uses post-processing that cuts out alpha values. > > Thanks! > Maxime -- Best regards, Roman Stratiienko Global Logic Inc. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
