2017-07-24 13:02 GMT+02:00 Nicolas George <geo...@nsup.org>: > Le sextidi 6 thermidor, an CCXXV, Carl Eugen Hoyos a écrit : >> > Oh, you mean a gradient on the alpha channel. It is not really possible >> > without making the code more complex and I think significantly slower. >> >> > A coarse gradient between the different vertical bands is easy, but the >> > alpha must be constant in each band, just like the color. >> >> (Why?) > > Because memset() is faster and simpler than anything else that could do > the work.
I thought that one of my suggestions (alpha_value = y * 255 / height) would play nice with memset(). > testsrc2 is based on the drawutils functions, which provide a > few drawing primitives, especially rectangles. They are limited in > features but are fast and support many pixel formats with little code. > >> Any change that provides different transparency values on one frame is >> a useful fix for a long-standing bug / missing feature imo. > > Note that with the current patch, while most of the drawing has constant > alpha, the beating cross and bouncing square ball are fully opaque, so > there are already two alpha values. It is better than nothing. Definitely. > I suggest we apply the patch as is, since it allows the overlay test to > move forward. And then we can consider how to add an interesting alpha > channel for better testing. > Is it ok with you? I am ok with everything that improves the current situation, I just wanted to point out a long-standing issue when I saw your patch. I cannot comment on the Plasma generator. Carl Eugen _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
