procyberian/emacs
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

(defined_color): If colormap is full, find closest match.

Browse source
This commit is contained in:
Richard M. Stallman 1995-03-06 04:33:56 +00:00
parent a992f9d90e
commit 829782956e
1 changed files with 61 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

69
src/xfns.c
View file

@ -963,6 +963,7 @@ x_report_frame_params (f, alistptr)
: FRAME_ICONIFIED_P (f) ? Qicon : Qnil));
}
/* Decide if color named COLOR is valid for the display associated with
the selected frame; if so, return the rgb values in COLOR_DEF.
If ALLOC is nonzero, allocate a new colormap cell. */
@ -974,20 +975,72 @@ defined_color (f, color, color_def, alloc)
XColor *color_def;
int alloc;
{
register int foo;
register int status;
Colormap screen_colormap;
Display *display = FRAME_X_DISPLAY (f);
BLOCK_INPUT;
screen_colormap
= DefaultColormap (FRAME_X_DISPLAY (f),
XDefaultScreen (FRAME_X_DISPLAY (f)));
screen_colormap = DefaultColormap (display, XDefaultScreen (display));
foo = XParseColor (FRAME_X_DISPLAY (f), screen_colormap, color, color_def);
if (foo && alloc)
foo = XAllocColor (FRAME_X_DISPLAY (f), screen_colormap, color_def);
status = XParseColor (display, screen_colormap, color, color_def);
if (status && alloc)
{
status = XAllocColor (display, screen_colormap, color_def);
if (!status)
{
/* If we got to this point, the colormap is full, so we're
going to try and get the next closest color.
The algorithm used is a least-squares matching, which is
what X uses for closest color matching with StaticColor visuals. */
XColor *cells;
int no_cells;
int nearest;
long nearest_delta, trial_delta;
int x;
no_cells = XDisplayCells (display, XDefaultScreen (display));
cells = (XColor *) alloca (sizeof (XColor) * no_cells);
for (x = 0; x < no_cells; x++)
cells[x].pixel = x;
XQueryColors (display, screen_colormap, cells, no_cells);
nearest = 0;
/* I'm assuming CSE so I'm not going to condense this. */
nearest_delta = ((((color_def->red >> 8) - (cells[0].red >> 8))
* ((color_def->red >> 8) - (cells[0].red >> 8)))
+
(((color_def->green >> 8) - (cells[0].green >> 8))
* ((color_def->green >> 8) - (cells[0].green >> 8)))
+
(((color_def->blue >> 8) - (cells[0].blue >> 8))
* ((color_def->blue >> 8) - (cells[0].blue >> 8))));
for (x = 1; x < no_cells; x++)
{
trial_delta = ((((color_def->red >> 8) - (cells[x].red >> 8))
* ((color_def->red >> 8) - (cells[x].red >> 8)))
+
(((color_def->green >> 8) - (cells[x].green >> 8))
* ((color_def->green >> 8) - (cells[x].green >> 8))) +
+
(((color_def->blue >> 8) - (cells[x].blue >> 8))
* ((color_def->blue >> 8) - (cells[x].blue >> 8))));
if (trial_delta < nearest_delta)
{
nearest = x;
nearest_delta = trial_delta;
}
}
color_def->red = cells[nearest].red;
color_def->green = cells[nearest].green;
color_def->blue = cells[nearest].blue;
status = XAllocColor (display, screen_colormap, color_def);
}
}
UNBLOCK_INPUT;
if (foo)
if (status)
return 1;
else
return 0;