> I'm working on some illustrations, and am not entirely satisfied with the
> fact that they look very artificial and computer-generated. Does anyone
> have any suggestions on ways of working with the gimp to produce artwork
> that is more "natural" looking? I'm particularly thinking of things like
> adding paper texture, making the ink/paint look less perfect or precise,
> etc. I guess the look I'm thinking of is more of gouache and watercolour.
I'm a big fan of a rough hand-drawn look. One thing I did that I'm
halfway happy with is a crosshatch filter I made for GIMP with
gimp-perl. It doesn't always create a believable cross-hatch effect. It
depends on the subject and the settings.
If you're creating stuff from scratch, there's nothing like a graphics
tablet. I've got a 6x8 Intuos USB, and I've really enjoyed working with
it. The pressure sensitivity is good enough that many of the tools draw
much like the real thing, just with a perfect eraser and unlimited undo.
I keep a sketchpad online at
http://www.nightdrivers.com/~samjones/images/
It's not high art, but I think it shows how tools can behave like pen,
pencil or brush.
#!/usr/bin/perl -w
use Gimp ":auto";
use Gimp::Fu;
sub pencil_crosshatch {
# Grab the image this routine modifies
my ($image,$drawable,$darkness,$trace_threshold,$trace_brush) = @_;
# Grab tracable area for later use
gimp_by_color_select($drawable,[0,0,0],$trace_threshold,2,0,0,0,0);
plug_in_sel2path($image,$drawable);
gimp_selection_none($image);
# NE Stroke is a layer handling the crosshatch going NE-SW
my $ne_stroke = gimp_layer_new($image,$image->width,$image->height,
$drawable->type,"NE Stroke",100,0);
# Add a layer onto image
$image->add_layer($ne_stroke,-1);
gimp_palette_set_background([255,255,255]);
gimp_edit_fill($ne_stroke,BG_IMAGE_FILL);
plug_in_noisify($image,$ne_stroke,0,.5,.5,.5,0);
plug_in_mblur($image,$ne_stroke,0,5,135);
# NW Stroke is a layer handling the crosshatch going NW-SE
my $nw_stroke = gimp_layer_new($image,$image->width,$image->height,
$drawable->type,"NW Stroke",100,3);
# Add a layer onto image
$image->add_layer($nw_stroke,-1);
gimp_palette_set_background([255,255,255]);
gimp_edit_fill($nw_stroke,BG_IMAGE_FILL);
plug_in_noisify($image,$nw_stroke,0,.5,.5,.5,0);
plug_in_mblur($image,$nw_stroke,0,5,45);
my $cross_layer = $image->merge_down($nw_stroke,1);
$cross_layer->set_mode(4);
# Use Darkness Parameter
gimp_levels($cross_layer,0,32*($darkness-1),255,1,0,255);
# Add in traced outline
# Trace is a layer handling a traced outline of the image.
my $outline = gimp_layer_new($image,$image->width,$image->height,
$drawable->type,"traced outline",100,3);
# Add a layer onto image
$image->add_layer($outline,-1);
gimp_palette_set_background([255,255,255]);
gimp_edit_fill($outline,BG_IMAGE_FILL);
gimp_brushes_set_brush($trace_brush);
gimp_path_stroke_current($image);
}
register "crosshatch","Makes image appear to have been drawn in pencil with" .
" crosshatch","pencil crosshatch","Sam Jones","Sam Jones","2001-16-04",
"<Image>/Filters/Artistic/Crosshatch","RGB*,GRAY*",[
[PF_SLIDER, "darkness", "Sketch Darkness",1,[1,9,1]],
[PF_SLIDER, "trace_threshold", "Trace Threshold",40,[1,255,1]],
[PF_BRUSH, "trace_brush", "Trace Brush","9x9cross"]
],\&pencil_crosshatch;
exit main();
