* app/image_render.c:
* app/tile.h: Removed the JIT calculation of the tile_shift
value and replaced it by a constant called TILE_SHIFT in tile.h.
This gives the compiler a better chance to optimize the code.
Also added a few consts all over the place to give the compiler
some hints.
* app/tile.c
* app/tile.h
* app/tile_manager.c
* app/tile_swap.c:
Allocate Tile's array of TileRowHints dynamically. Make type
of TileRowHint explicit since it's fairly space-critical.
Can save several hundred K of memory with this and struct
changes.
Added warnings for old basically-untested-or-insane
paths through the tile referencing code.
* app/tile_pvt.h: Shrink down and rearrange fields of Tile
struct to save some space with gcc's padding for most people.
* app/paint_funcs.c: Use tile_sanitize_rowhints() to ensure
that rowhints have been allocated before use.
* app/channel_ops.c
* app/gdisplay.c
* app/pixel_region.c: Cosmetic, sanity or unfinished debug
changes (the latter commented out) for fun and reference.
Sun May 9 16:23:47 BST 1999 Adam D. Moss <adam@gimp.org>
* app/tile.c
* app/tile.h
* app/tile_manager.c
* app/tile_pvt.h
* app/paint_funcs.c:
Added Tile Row Hinting to the GIMP tile structure. Tiles
now have cheap per-row hints indicating whether each row is
all-transparent, all-opaque, a mixture, or other properties.
These hints are automatically invalidated when the tile is checked
in as dirty, and are re-evaluated on demand.
Currently only the layer compositing routines take advantage
of these hints, though there is opportunity to use them to
advantage in numerous other places.
The whole layer compositing process is typically 2x-4x faster
now, especially on subsequent renders of data which has already
had its hints calculated.
See tile.h for the explicit TileRowHint query/set interface.
The procedure to re-evaluate tile hints currently resides in
paint_funcs.c but may be exposed to other parts of the core
if necessary.
This is experimental. Please report mis-rendering problems.
Modified tile swapping to preswap dirty tiles, using a thread if
threads are enabled in configure or a gtk_timeout if they're not. The
code appears stable but could use improvement. Be careful when
working in here; there are four sets of semaphores and getting the
locking wrong will cause deadlocks or tile corruption. I'll try to
write up a document describing what's going on in here sometime soon.
--sg
