Let's suppose that you have your oh-so-tweaked XFree86 mode and you want to evaluate Xinside in the same conditions: follow the steps described below and you should be able to do it; we will use my default video mode as a real-life example and I will explain what you will have to do to convert it.
An Xfree86 entry looks like this:
Modeline "blahblah" DOTCLK A B C D a b c d
Every one of the A-D and a-d numbers has a meaning: if you want you can search for it in the 'The Hitchhiker's Guide to X386/XFree86 Video Timing' ( /usr/lib/X11/doc/VideoModes.doc ) but you don't need to know the theory behind all this to perform a succesful conversion...
My modeline in /usr/lib/X11/XF86Config is:
Modeline "1168x876" 105 1168 1256 1544 1640 876 877 891 900
| | | | | | | | |
DOT_CLK A B C D a b c d
In Xinside, you have to add an entry in the Xtimings file, which should be located in etc/ ( from now on we suppose you are in the top Xaccel directory that should be something like /usr/X11/lib/X11/AcceleratedX )
! Somewhere in the file, put here the name you want
[PREADJUSTED_TIMING]
PreadjustedTimingName = "1168x876 @ 72Hz";
!
! These four are obvious
!
HorPixel = 1168; // pixels
VerPixel = 876; // lines
PixelWidthRatio = 4;
PixelHeightRatio = 3;
!
! hsync: DOT_CLK / D * 1000 [KHz]
!
! hsync = 105 / 1640 * 1000 = 64.024 KHz
!
! vsync: ( 1 / (( D / DOT_CLK ) * d) ) * 1,000,000 [Hz]
!
! vsync: ( 1 / (( 1640 / 105 ) * 900) ) * 1,000,000
! ( 1 / 14057.1428571 ) * 1,000,000 = 71.138 Hz
!
HorFrequency = 64.180; // kHz
VerFrequency = 71.138; // Hz
! Obvious
ScanType = NONINTERLACED;
!
! Put here the +/-hsync +/-vsync XFree86 options
!
HorSyncPolarity = POSITIVE;
VerSyncPolarity = POSITIVE;
! Shouldn't change
CharacterWidth = 8; // pixels
! DOT_CLK here
PixelClock = 105.000; // MHz
!
!
! horizontal timings section: [usec]
!
HorTotalTime = D / DOT_CLK = 15.619;
HorAddrTime = A / DOT_CLK = 11.124;
HorBlankStart = A / DOT_CLK = 11.124;
HorBlankTime = HorTotalTime - HorBlankStart = 4.495;
HorSyncStart = B / DOT_CLK = 11.962;
HorSyncTime = C / DOT_CLK - HorSyncStart = 2.743;
!
! vertical timings section: [msec]
!
VerTotalTime = ( HorTotalTime * d ) / 1000 = 14.057;
VerAddrTime = ( HorTotalTime * a ) / 1000 = 13.682;
VerBlankStart = ( HorTotalTime * a ) / 1000 = 13.682;
VerBlankTime = VerTotalTime - VerBlankStart = 0.375;
VerSyncStart = ( HorTotalTime * b ) / 1000 = 13.698;
VerSyncTime = ( HorTotalTime * ( c - b ) ) / 1000
= 0.219
! Finished !
Now you have to put this newly created mode in the files shown below in the appropriate place.