On Tuesday, 5 Dec 2000, David Bonnell wrote:
> On Wed, 6 Dec 2000, Austin Donnelly wrote:
>
> > ...
> > Probably the easiest way would be to use select by colour, but that
> > would catch other stuff that was a similar colour.
> >
> Could change "Select by Colour" to only select pixels within the current
> selection if there is one, or the entire image (or layer) if there
> isn't an active selection.
>
> > With this, you could lasso the general area the text is in, then go
> > <Image>/Selection/Tighten to get just your text.
> >
> That would certainly be a very useful tool.
Oops. I accidentally implemented it.
Patch against 1.1.29 attached below.
It needs some work:
o The algorithm to find the start point for the seed fill is pretty
dumb: it picks the topmost image pixel in the selection, and flood
fills from there. Plus its a really inefficient implementation of
this brain dead algorithm.
o No PDB access functions.
o No help file.
o No way to tweak edge detection threshold
o No way to set sample merged, so it only works on the current layer
(These last two are because it has no UI. I don't think it should
have a UI since it's supposed to be quick and just do the right
thing. Mostly it does.)
If anyone feels like playing with it, let me know how you get on.
I think it's pretty cool (but then I'm biased).
Austin
--- commands.c~ Mon Oct 30 01:33:11 2000
+++ commands.c Wed Dec 6 17:05:24 2000
@@ -390,6 +390,19 @@
gtk_widget_show (shrink_dialog);
}
+
+void
+select_tighten_cmd_callback (GtkWidget *widget,
+ gpointer client_data)
+{
+ GDisplay *gdisp;
+ return_if_no_display (gdisp);
+
+ gimage_mask_tighten (gdisp->gimage);
+ gdisplays_flush ();
+}
+
+
void
select_grow_cmd_callback (GtkWidget *widget,
gpointer client_data)
--- commands.h~ Mon Oct 30 01:33:11 2000
+++ commands.h Wed Dec 6 17:25:14 2000
@@ -52,6 +52,7 @@
void select_feather_cmd_callback (GtkWidget *, gpointer);
void select_sharpen_cmd_callback (GtkWidget *, gpointer);
void select_shrink_cmd_callback (GtkWidget *, gpointer);
+void select_tighten_cmd_callback (GtkWidget *, gpointer);
void select_border_cmd_callback (GtkWidget *, gpointer);
void select_grow_cmd_callback (GtkWidget *, gpointer);
void select_save_cmd_callback (GtkWidget *, gpointer);
--- gimage_mask.c~ Mon Oct 30 01:33:14 2000
+++ gimage_mask.c Wed Dec 6 18:06:40 2000
@@ -22,6 +22,7 @@
#include "floating_sel.h"
#include "gdisplay.h"
#include "gimage_mask.h"
+#include "fuzzy_select.h"
#include "gimprc.h"
#include "layer.h"
#include "paint_core.h"
@@ -478,6 +479,55 @@
edge_lock);
}
+
+void
+gimage_mask_tighten (GImage *gimage)
+{
+ Channel *mask;
+ Channel *shrinkage;
+ GimpDrawable *drawable;
+ gint x1, y1, x2, y2;
+ gint x;
+
+ g_return_if_fail (gimage != NULL);
+ drawable = gimage_active_drawable (gimage);
+ g_return_if_fail (drawable != NULL);
+
+ mask = gimage_get_mask (gimage);
+ g_return_if_fail (mask != NULL);
+
+ undo_push_group_start (gimage, MASK_UNDO);
+
+ channel_push_undo (mask);
+
+ /* if there was no selection, then assume the entire image was selected */
+ if (channel_is_empty (mask))
+ channel_all (mask);
+
+ /* Pick a point within the selection from which to start the seed
+ * fill. */
+ channel_bounds (mask, &x1, &y1, &x2, &y2);
+ x = x1;
+ /* XXX FIXME: seriously costly loop: should do pixel iteration
+ * ourselves */
+ while (x < x2 && channel_value (mask, x, y1) < 128)
+ x++;
+
+ /* XXX Need to find some way of presenting the threshold and sample
+ * merged options to the user, without getting in their way. */
+ shrinkage = find_contiguous_region (gimage, drawable,
+ /* antialias */ TRUE,
+ /* threshold */ 15,
+ x, y1,
+ /* sample merged */ 0);
+ channel_combine_mask (mask, shrinkage, SUB, 0, 0);
+ channel_delete (shrinkage);
+
+ gimage_mask_invalidate (gimage);
+
+ undo_push_group_end (gimage);
+}
+
void
gimage_mask_layer_alpha (GImage *gimage,
--- gimage_mask.h~ Mon Oct 30 01:33:14 2000
+++ gimage_mask.h Wed Dec 6 17:29:56 2000
@@ -81,6 +81,8 @@
gint shrink_pixels_y,
gboolean edge_lock);
+void gimage_mask_tighten (GImage *gimage);
+
void gimage_mask_layer_alpha (GImage *gimage,
Layer *layer);
--- menus.c~ Mon Oct 30 01:33:22 2000
+++ menus.c Wed Dec 6 17:24:42 2000
@@ -285,6 +285,8 @@
"select/sharpen.html", NULL },
{ { N_("/Select/Shrink..."), NULL, select_shrink_cmd_callback, 0 },
"select/dialogs/shrink_selection.html", NULL },
+ { { N_("/Select/Tighten"), NULL, select_tighten_cmd_callback, 0 } ,
+ "select/dialogs/tighten_selection.html", NULL },
{ { N_("/Select/Grow..."), NULL, select_grow_cmd_callback, 0 },
"select/dialogs/grow_selection.html", NULL },
{ { N_("/Select/Border..."), "<control><shift>B", select_border_cmd_callback, 0 },
