diff options
Diffstat (limited to 'xorg-server/hw/xfree86/ramdac/CURSOR.NOTES')
-rw-r--r-- | xorg-server/hw/xfree86/ramdac/CURSOR.NOTES | 382 |
1 files changed, 191 insertions, 191 deletions
diff --git a/xorg-server/hw/xfree86/ramdac/CURSOR.NOTES b/xorg-server/hw/xfree86/ramdac/CURSOR.NOTES index a0ecd02ae..726e2edc1 100644 --- a/xorg-server/hw/xfree86/ramdac/CURSOR.NOTES +++ b/xorg-server/hw/xfree86/ramdac/CURSOR.NOTES @@ -1,191 +1,191 @@ - CURSOR.NOTES
-
- This file describes how to add hardware cursor support to a chipset
-driver. Though the cursor support itself is in the ramdac module,
-cursor management is separate from the rest of the module.
-
-
-1) CURSOR INITIALIZATION AND SHUTDOWN
-
- All relevant prototypes and defines are in xf86Cursor.h.
-
- To initialize the cursor, the driver should allocate an
-xf86CursorInfoRec via xf86CreateCursorInfoRec(), fill it out as described
-later in this document and pass it to xf86InitCursor(). xf86InitCursor()
-must be called _after_ the software cursor initialization (usually
-miDCInitialize).
-
- When shutting down, the driver should free the xf86CursorInfoRec
-structure in its CloseScreen function via xf86DestroyCursorInfoRec().
-
-
-2) FILLING OUT THE xf86CursorInfoRec
-
- The driver informs the ramdac module of it's hardware cursor capablities by
-filling out an xf86CursorInfoRec structure and passing it to xf86InitCursor().
-The xf86CursorInfoRec contains the following function pointers:
-
-
-/**** These functions are required ****/
-
-void ShowCursor(ScrnInfoPtr pScrn)
-
- ShowCursor should display the current cursor.
-
-void HideCursor(ScrnInfoPtr pScrn)
-
- HideCursor should hide the current cursor.
-
-void SetCursorPosition(ScrnInfoPtr pScrn, int x, int y)
-
- Set the cursor position to (x,y). X and/or y may be negative
- indicating that the cursor image is partially offscreen on
- the left and/or top edges of the screen. It is up to the
- driver to trap for this and deal with that situation.
-
-void SetCursorColors(ScrnInfoPtr pScrn, int bg, int fg)
-
- Set the cursor foreground and background colors. In 8bpp, fg and
- bg are indicies into the current colormap unless the
- HARDWARE_CURSOR_TRUECOLOR_AT_8BPP flag is set. In that case
- and in all other bpps the fg and bg are in 8-8-8 RGB format.
-
-void LoadCursorImage(ScrnInfoPtr pScrn, unsigned char *bits)
-
- LoadCursorImage is how the hardware cursor bits computed by the
- RealizeCursor function will be passed to the driver when the cursor
- shape needs to be changed.
-
-
-/**** These functions are optional ****/
-
-
-unsigned char* RealizeCursor(xf86CursorInfoPtr infoPtr, CursorPtr pCurs)
-
- If RealizeCursor is not provided by the driver, one will be provided
- for you based on the Flags field described below. The driver must
- provide this function if the hardware cursor format is not one of
- the common ones supported by this module.
-
-
-Bool UseHWCursor(ScreenPtr pScreen, CursorPtr pCurs)
-
- If the driver is unable to use a hardware cursor for reasons
- other than the cursor being larger than the maximum specified
- in the MaxWidth or MaxHeight field below, it can supply the
- UseHWCursor function. If UseHWCursor is provided by the driver,
- it will be called whenever the cursor shape changes or the video
- mode changes. This is useful for when the hardware cursor cannot
- be used in interlaced or doublescan modes.
-
-
-/**** The following fields are required ****/
-
-MaxWidth
-MaxHeight
-
- These indicate the largest sized cursor that can be a hardware
- cursor. It will fall back to a software cursor when a cursor
- exceeding this size needs to be used.
-
-
-Flags
-
- /* Color related flags */
-
- HARDWARE_CURSOR_TRUECOLOR_AT_8BPP
-
- This indicates that the colors passed to the SetCursorColors
- function should not be in 8-8-8 RGB format in 8bpp but rather,
- they should be the pixel values from the current colormap.
-
-
- /* Cursor data loading flags */
-
- HARDWARE_CURSOR_SHOW_TRANSPARENT
-
- The HideCursor entry will normally be called instead of displaying a
- completely transparent cursor, or when a switch to a software cursor
- needs to occur. This flag prevents this behaviour, thus causing the
- LoadCursorImage entry to be called with transparent cursor data.
- NOTE: If you use this flag and provide your own RealizeCursor() entry,
- ensure this entry returns transparent cursor data when called
- with a NULL pCurs parameter.
-
- HARDWARE_CURSOR_UPDATE_UNHIDDEN
-
- This flag prevents the HideCursor call that would normally occur just before
- the LoadCursorImage entry is to be called to load a new hardware cursor
- image.
-
-
- /* Cursor data packing flags */
-
- Hardware cursor data consists of two pieces, a source and a mask.
- The mask is a bitmap indicating which parts of the cursor are
- transparent and which parts are drawn. The source is a bitmap
- indicating which parts of the non-transparent portion of the the
- cursor should be painted in the foreground color and which should
- be painted in the background color.
-
- HARDWARE_CURSOR_INVERT_MASK
-
- By default, set bits indicate the opaque part of the mask bitmap
- and clear bits indicate the transparent part. If your hardware
- wants this the opposite way, this flag will invert the mask.
-
- HARDWARE_CURSOR_SWAP_SOURCE_AND_MASK
-
- By default, RealizeCursor will store the source first and then
- the mask. If the hardware needs this order reversed then this
- flag should be set.
-
- HARDWARE_CURSOR_AND_SOURCE_WITH_MASK
-
- This flag will have the module logical AND the source with the mask to make
- sure there are no source bits set if the corresponding mask bits
- aren't set. Some hardware will not care if source bits are set where
- there are supposed to be transparent areas, but some hardware will
- interpret this as a third cursor color or similar. That type of
- hardware will need this flag set.
-
- HARDWARE_CURSOR_BIT_ORDER_MSBFIRST
-
- By default, it is assumed that the least significant bit in each byte
- corresponds to the leftmost pixel on the screen. If your hardware
- has this reversed you should set this flag.
-
- HARDWARE_CURSOR_NIBBLE_SWAPPED
-
- If your hardware requires byte swapping of the hardware cursor, enable
- this option.
-
-
- /* Source-Mask interleaving flags */
-
- By default the source and mask data are inlined (source first unless
- the HARDWARE_CURSOR_SWAP_SOURCE_AND_MASK flag is set). Some hardware
- will require the source and mask to be interleaved, that is, X number
- of source bits should packed and then X number of mask bits repeating
- until the entire pattern is stored. The following flags describe the
- bit interleave.
-
- HARDWARE_CURSOR_SOURCE_MASK_NOT_INTERLEAVED
-
- This one is the default.
-
- The following are for interleaved cursors.
-
- HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_1
- HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_8
- HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_16
- HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_32
- HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_64
-
- And once again, if your hardware requires something different than
- these packing styles, your driver can supply its own RealizeCursor
- function.
-
-
-
-$XFree86: xc/programs/Xserver/hw/xfree86/ramdac/CURSOR.NOTES,v 1.4tsi Exp $
+ CURSOR.NOTES + + This file describes how to add hardware cursor support to a chipset +driver. Though the cursor support itself is in the ramdac module, +cursor management is separate from the rest of the module. + + +1) CURSOR INITIALIZATION AND SHUTDOWN + + All relevant prototypes and defines are in xf86Cursor.h. + + To initialize the cursor, the driver should allocate an +xf86CursorInfoRec via xf86CreateCursorInfoRec(), fill it out as described +later in this document and pass it to xf86InitCursor(). xf86InitCursor() +must be called _after_ the software cursor initialization (usually +miDCInitialize). + + When shutting down, the driver should free the xf86CursorInfoRec +structure in its CloseScreen function via xf86DestroyCursorInfoRec(). + + +2) FILLING OUT THE xf86CursorInfoRec + + The driver informs the ramdac module of it's hardware cursor capablities by +filling out an xf86CursorInfoRec structure and passing it to xf86InitCursor(). +The xf86CursorInfoRec contains the following function pointers: + + +/**** These functions are required ****/ + +void ShowCursor(ScrnInfoPtr pScrn) + + ShowCursor should display the current cursor. + +void HideCursor(ScrnInfoPtr pScrn) + + HideCursor should hide the current cursor. + +void SetCursorPosition(ScrnInfoPtr pScrn, int x, int y) + + Set the cursor position to (x,y). X and/or y may be negative + indicating that the cursor image is partially offscreen on + the left and/or top edges of the screen. It is up to the + driver to trap for this and deal with that situation. + +void SetCursorColors(ScrnInfoPtr pScrn, int bg, int fg) + + Set the cursor foreground and background colors. In 8bpp, fg and + bg are indicies into the current colormap unless the + HARDWARE_CURSOR_TRUECOLOR_AT_8BPP flag is set. In that case + and in all other bpps the fg and bg are in 8-8-8 RGB format. + +void LoadCursorImage(ScrnInfoPtr pScrn, unsigned char *bits) + + LoadCursorImage is how the hardware cursor bits computed by the + RealizeCursor function will be passed to the driver when the cursor + shape needs to be changed. + + +/**** These functions are optional ****/ + + +unsigned char* RealizeCursor(xf86CursorInfoPtr infoPtr, CursorPtr pCurs) + + If RealizeCursor is not provided by the driver, one will be provided + for you based on the Flags field described below. The driver must + provide this function if the hardware cursor format is not one of + the common ones supported by this module. + + +Bool UseHWCursor(ScreenPtr pScreen, CursorPtr pCurs) + + If the driver is unable to use a hardware cursor for reasons + other than the cursor being larger than the maximum specified + in the MaxWidth or MaxHeight field below, it can supply the + UseHWCursor function. If UseHWCursor is provided by the driver, + it will be called whenever the cursor shape changes or the video + mode changes. This is useful for when the hardware cursor cannot + be used in interlaced or doublescan modes. + + +/**** The following fields are required ****/ + +MaxWidth +MaxHeight + + These indicate the largest sized cursor that can be a hardware + cursor. It will fall back to a software cursor when a cursor + exceeding this size needs to be used. + + +Flags + + /* Color related flags */ + + HARDWARE_CURSOR_TRUECOLOR_AT_8BPP + + This indicates that the colors passed to the SetCursorColors + function should not be in 8-8-8 RGB format in 8bpp but rather, + they should be the pixel values from the current colormap. + + + /* Cursor data loading flags */ + + HARDWARE_CURSOR_SHOW_TRANSPARENT + + The HideCursor entry will normally be called instead of displaying a + completely transparent cursor, or when a switch to a software cursor + needs to occur. This flag prevents this behaviour, thus causing the + LoadCursorImage entry to be called with transparent cursor data. + NOTE: If you use this flag and provide your own RealizeCursor() entry, + ensure this entry returns transparent cursor data when called + with a NULL pCurs parameter. + + HARDWARE_CURSOR_UPDATE_UNHIDDEN + + This flag prevents the HideCursor call that would normally occur just before + the LoadCursorImage entry is to be called to load a new hardware cursor + image. + + + /* Cursor data packing flags */ + + Hardware cursor data consists of two pieces, a source and a mask. + The mask is a bitmap indicating which parts of the cursor are + transparent and which parts are drawn. The source is a bitmap + indicating which parts of the non-transparent portion of the the + cursor should be painted in the foreground color and which should + be painted in the background color. + + HARDWARE_CURSOR_INVERT_MASK + + By default, set bits indicate the opaque part of the mask bitmap + and clear bits indicate the transparent part. If your hardware + wants this the opposite way, this flag will invert the mask. + + HARDWARE_CURSOR_SWAP_SOURCE_AND_MASK + + By default, RealizeCursor will store the source first and then + the mask. If the hardware needs this order reversed then this + flag should be set. + + HARDWARE_CURSOR_AND_SOURCE_WITH_MASK + + This flag will have the module logical AND the source with the mask to make + sure there are no source bits set if the corresponding mask bits + aren't set. Some hardware will not care if source bits are set where + there are supposed to be transparent areas, but some hardware will + interpret this as a third cursor color or similar. That type of + hardware will need this flag set. + + HARDWARE_CURSOR_BIT_ORDER_MSBFIRST + + By default, it is assumed that the least significant bit in each byte + corresponds to the leftmost pixel on the screen. If your hardware + has this reversed you should set this flag. + + HARDWARE_CURSOR_NIBBLE_SWAPPED + + If your hardware requires byte swapping of the hardware cursor, enable + this option. + + + /* Source-Mask interleaving flags */ + + By default the source and mask data are inlined (source first unless + the HARDWARE_CURSOR_SWAP_SOURCE_AND_MASK flag is set). Some hardware + will require the source and mask to be interleaved, that is, X number + of source bits should packed and then X number of mask bits repeating + until the entire pattern is stored. The following flags describe the + bit interleave. + + HARDWARE_CURSOR_SOURCE_MASK_NOT_INTERLEAVED + + This one is the default. + + The following are for interleaved cursors. + + HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_1 + HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_8 + HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_16 + HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_32 + HARDWARE_CURSOR_SOURCE_MASK_INTERLEAVE_64 + + And once again, if your hardware requires something different than + these packing styles, your driver can supply its own RealizeCursor + function. + + + +$XFree86: xc/programs/Xserver/hw/xfree86/ramdac/CURSOR.NOTES,v 1.4tsi Exp $ |