On Tue, Jan 13, 2009 at 12:23 PM, Felipe Contreras <felipe.contre...@gmail.com> wrote: > On Tue, Jan 13, 2009 at 12:05 PM, Igor Stoppa <igor.sto...@nokia.com> wrote: >> Hi, >> On Tue, 2009-01-13 at 18:06 +0800, ext Huang Gao (Gmail) wrote: >>> Hi, Igor Stoppa: >>> Thank you for your reply! >>> So can I understand that this hardware FB is not contained in SDRAM >>> or SRAM, and LCD will refresh itself from this hardware FB by its controller >>> automatically, without the help of OMAP DMA channel? >> >> I'm in no way a display guy but iirc there are 2 modes for refresh: >> -auto: whatever is written to the framebuffer goes through straight to >> the LCD >> -manual: the image needs to be flushed to the LCD >> >> If you are interested, you can check it from the kernel source files. > > Would the manual mode help to avoid tearing?
Yes, and it does help to avoid tearing. At least this works fine for XV extension. But getting tearfree scrolling/panning in GTK applications for example is a bit more challenging. I can provide a more detailed explanation if anybody is interested. XV should make a perfect backend for SDL, because it maps fine on SDL API (SDL_SetVideoMode/SDL_Flip/...). In general, XV is a good backend for anything that uses double-buffered or triple-buffered fullscreen/fullwindow blits. It is possible to get ~27.5 frames per second in 800x480 resolution for 16bpp rgb color format without tearing. With a lower resolution it is possible to go up to ~55 frames per second. _______________________________________________ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
