gimp/app/core/gimpdrawable-stroke.c

/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * gimpdrawable-stroke.c
 * Copyright (C) 2003 Simon Budig  <simon@gimp.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include "config.h"

#include <glib-object.h>

#include "libgimpcolor/gimpcolor.h"

#include "core-types.h"

#include "base/boundary.h"
#include "base/pixel-region.h"
#include "base/temp-buf.h"
#include "base/tile-manager.h"

#include "paint-funcs/paint-funcs.h"

#include "gimp.h"
#include "gimpchannel.h"
#include "gimpcontext.h"
#include "gimpdrawable-stroke.h"
#include "gimpimage.h"
#include "gimppattern.h"
#include "gimpscanconvert.h"
#include "gimpstrokeoptions.h"
#include "gimpunit.h"

#include "vectors/gimpstroke.h"
#include "vectors/gimpvectors.h"

#include "gimp-intl.h"


/*  local function prototypes  */

static void gimp_drawable_stroke_scan_convert (GimpDrawable      *drawable,
                                               GimpStrokeOptions *options,
                                               GimpScanConvert   *scan_convert);


/*  public functions  */

void
gimp_drawable_stroke_boundary (GimpDrawable      *drawable,
                               GimpStrokeOptions *options,
                               const BoundSeg    *bound_segs,
                               gint               n_bound_segs,
                               gint               offset_x,
                               gint               offset_y)
{
  GimpScanConvert *scan_convert;
  BoundSeg        *sorted_segs;
  BoundSeg        *stroke_segs;
  gint             n_stroke_segs;
  GimpVector2     *points;
  gint             n_points;
  gint             seg;
  gint             i;

  g_return_if_fail (GIMP_IS_DRAWABLE (drawable));
  g_return_if_fail (GIMP_IS_STROKE_OPTIONS (options));
  g_return_if_fail (bound_segs != NULL);
  g_return_if_fail (n_bound_segs > 0);

  sorted_segs = sort_boundary (bound_segs, n_bound_segs, &n_stroke_segs);
  stroke_segs = simplify_boundary (sorted_segs, n_stroke_segs, &n_bound_segs);

  g_free (sorted_segs);

  if (n_stroke_segs == 0)
    return;

  scan_convert = gimp_scan_convert_new ();

  points = g_new0 (GimpVector2, n_bound_segs + 4);

  seg = 0;
  n_points = 0;

  /* we offset all coordinates by 0.5 to align the brush with the path */

  points[n_points].x = (gdouble) (stroke_segs[0].x1 + offset_y + 0.5);
  points[n_points].y = (gdouble) (stroke_segs[0].y1 + offset_y + 0.5);

  n_points++;

  for (i = 0; i < n_stroke_segs; i++)
    {
      while (stroke_segs[seg].x1 != -1 ||
             stroke_segs[seg].x2 != -1 ||
             stroke_segs[seg].y1 != -1 ||
             stroke_segs[seg].y2 != -1)
        {
          points[n_points].x = (gdouble) (stroke_segs[seg].x1 + offset_x + 0.5);
          points[n_points].y = (gdouble) (stroke_segs[seg].y1 + offset_y + 0.5);

          n_points++;
          seg++;
        }

      /* Close the stroke points up */
      points[n_points] = points[0];

      n_points++;

      gimp_scan_convert_add_polyline (scan_convert, n_points, points, TRUE);

      n_points = 0;
      seg++;

      points[n_points].x = (gdouble) (stroke_segs[seg].x1 + offset_x + 0.5);
      points[n_points].y = (gdouble) (stroke_segs[seg].y1 + offset_y + 0.5);

      n_points++;
    }

  g_free (points);
  g_free (stroke_segs);

  gimp_drawable_stroke_scan_convert (drawable, options, scan_convert);

  gimp_scan_convert_free (scan_convert);
}

void
gimp_drawable_stroke_vectors (GimpDrawable      *drawable,
                              GimpStrokeOptions *options,
                              GimpVectors       *vectors)
{
  GimpScanConvert *scan_convert;
  GimpStroke      *stroke;
  gint             num_coords = 0;

  g_return_if_fail (GIMP_IS_DRAWABLE (drawable));
  g_return_if_fail (GIMP_IS_STROKE_OPTIONS (options));
  g_return_if_fail (GIMP_IS_VECTORS (vectors));

  scan_convert = gimp_scan_convert_new ();

  /* For each Stroke in the vector, interpolate it, and add it to the
   * ScanConvert
   */
  for (stroke = gimp_vectors_stroke_get_next (vectors, NULL);
       stroke;
       stroke = gimp_vectors_stroke_get_next (vectors, stroke))
    {
      GimpVector2 *points;
      gboolean     closed;
      GArray      *coords;
      gint i;

      /* Get the interpolated version of this stroke, and add it to our
       * scanconvert.
       */
      coords = gimp_stroke_interpolate (stroke, 0.2, &closed);

      if (coords && coords->len)
        {
          points = g_new0 (GimpVector2, coords->len);

          for (i = 0; i < coords->len; i++)
            {
              points[i].x = g_array_index (coords, GimpCoords, i).x;
              points[i].y = g_array_index (coords, GimpCoords, i).y;
              num_coords++;
            }

          gimp_scan_convert_add_polyline (scan_convert, coords->len,
                                          points, closed);

          g_free (points);
        }

      if (coords)
        g_array_free (coords, TRUE);
    }

  if (num_coords > 0)
    gimp_drawable_stroke_scan_convert (drawable, options, scan_convert);

  gimp_scan_convert_free (scan_convert);
}


/*  private functions  */

static void
gimp_drawable_stroke_scan_convert (GimpDrawable      *drawable,
                                   GimpStrokeOptions *options,
                                   GimpScanConvert   *scan_convert)
{
  /* Stroke options */
  gdouble      width;
  GArray      *dash_array = NULL;
  TileManager *base;
  TileManager *mask;
  gint         x1, x2, y1, y2, bytes, w, h;
  guchar       bg[1] = { 0, };
  PixelRegion  maskPR, basePR;
  GimpContext *context;
  GimpImage   *gimage;

  context = GIMP_CONTEXT (options);

  gimage = gimp_item_get_image (GIMP_ITEM (drawable));

  /* what area do we operate on? */
  if (! gimp_channel_is_empty (gimp_image_get_mask (gimage)))
    {
      gimp_drawable_mask_bounds (drawable, &x1, &y1, &x2, &y2);

      w = x2 - x1;
      h = y2 - y1;
    }
  else
    {
      x1 = y1 = 0;
      w = gimp_item_width (GIMP_ITEM (drawable));
      h = gimp_item_height (GIMP_ITEM (drawable));
    }

  gimp_item_offsets (GIMP_ITEM (drawable), &x2, &y2);

  width = options->width;

  if (options->unit != GIMP_UNIT_PIXEL)
    {
      gimp_scan_convert_set_pixel_ratio (scan_convert,
                                         gimage->yresolution /
                                         gimage->xresolution);

      width *= (gimage->yresolution /
                _gimp_unit_get_factor (gimage->gimp, options->unit));
    }

  gimp_scan_convert_stroke (scan_convert, width,
                            options->join_style,
                            options->cap_style,
                            options->miter,
                            0.0, dash_array);

  /* fill a 1-bpp Tilemanager with black, this will describe the shape
   * of the stroke.
   */
  mask = tile_manager_new (w, h, 1);
  pixel_region_init (&maskPR, mask, 0, 0, w, h, TRUE);
  color_region (&maskPR, bg);

  /* render the stroke into it */
  gimp_scan_convert_render (scan_convert, mask,
                            x1 + x2, y1 + y2,
                            options->antialias);

  bytes = drawable->bytes;
  if (!gimp_drawable_has_alpha (drawable))
    bytes++;

  base = tile_manager_new (w, h, bytes);
  tile_manager_set_offsets (base, x1 + x2, y1 + y2);
  pixel_region_init (&basePR, base, 0, 0, w, h, TRUE);
  pixel_region_init (&maskPR, mask, 0, 0, w, h, FALSE);

  switch (options->style)
    {
    case GIMP_STROKE_STYLE_SOLID:
      {
        guchar  tmp_col[MAX_CHANNELS] = { 0, };
        guchar  col[MAX_CHANNELS]     = { 0, };

        gimp_rgb_get_uchar (&(context->foreground),
                            &tmp_col[RED_PIX],
                            &tmp_col[GREEN_PIX],
                            &tmp_col[BLUE_PIX]);

        gimp_image_transform_color (gimage, drawable,
                                    col, GIMP_RGB, tmp_col);
        col[bytes - 1] = OPAQUE_OPACITY;

        color_region_mask (&basePR, &maskPR, col);
      }
      break;

    case GIMP_STROKE_STYLE_PATTERN:
      {
        GimpPattern *pattern;
        TempBuf     *pat_buf;
        gboolean     new_buf;

        g_object_get (options, "pattern", &pattern, NULL);
        pat_buf = gimp_image_transform_temp_buf (gimage, drawable,
                                                 pattern->mask, &new_buf);
        g_object_unref (pattern);

        pattern_region (&basePR, &maskPR, pat_buf, x1, y1);

        if (new_buf)
          temp_buf_free (pat_buf);
      }
      break;
    }

  /* Apply to drawable */
  pixel_region_init (&basePR, base, 0, 0, w, h, FALSE);
  gimp_drawable_apply_region (drawable, &basePR,
                              TRUE, _("Render Stroke"),
                              gimp_context_get_opacity (context),
                              gimp_context_get_paint_mode (context),
                              NULL, x1, y1);

  tile_manager_unref (mask);
  tile_manager_unref (base);

  gimp_drawable_update (drawable, x1, y1, w, h);
}