On Fri, Feb 11, 2011 at 7:53 PM, Keith Packard <kei...@keithp.com> wrote: > On Fri, 11 Feb 2011 13:16:38 +0100, Maarten Maathuis <madman2...@gmail.com> > wrote: >> 2011/2/11 Keith Packard <kei...@keithp.com>: > >> I'll admit i wasn't thinking about "odd" visuals when i did this and >> at the time the review process of patches certainly wasn't what it is >> today. > > I think the main issue is that the 'RandR' code lives in parallel with > the 'classic' code and so we end up supporting essentially two driver > stacks at this point. At some point, it would be lovely to figure out a > plan to clean all of this up. > > The basic problem is that the driver now exposes two parallel colormap > setting APIs -- the per-CRTC 'gamma_set' function and the per-screen > 'LoadPalette' function. Neither of these is the right API -- gamma_set > loads the whole colormap instead of just a piece (which would make > StoreColors really slow). The DRM kernel interface also deals only with > the whole colormap though. > > Go check out I830LoadPalette though -- as far as I can tell, it only > works when called to write the whole colormap, so it should only work > for StaticGray, StaticColor and TrueColor. Any other visual type will > cause uninitialized values to get loaded into the LUT.
There are dynamic colormaps? > > To recap, it looks like fixing this requires: > > 1) Fixing the gamma_set driver API to deal with partial updates. I'd > suggest that we add a new driver API (set_lut) that provides for > partial LUT writes and emulating that with gamma_set for existing > drivers. We can consider renaming 'get_gamma' at some point, but > I don't see any reason to change its signature. > > 2) Emulate the new 'set_lut' function on drivers that don't support it > by calling the existing LoadPalette function when asked to write > values to the 'compat_output' crtc. > > 3) Rewrite the existing colormap code to do per-crtc LUT computations > and use the 'set_lut' function to write those to the hardware. > > Drivers can be migrated to the 'set_lut' API once we fix the kernel API > to support partial LUT updates. > > I'd love to hear a simpler plan... > > -- > keith.pack...@intel.com > -- Far away from the primal instinct, the song seems to fade away, the river get wider between your thoughts and the things we do and say. _______________________________________________ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
