gimptransformtool.c

/* The GIMP -- an image manipulation program
 * Copyright (C) 1995-2001 Spencer Kimball, Peter Mattis, and others
 *
 * 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 <stdlib.h>

#include <gtk/gtk.h>

#include "libgimpmath/gimpmath.h"
#include "libgimpwidgets/gimpwidgets.h"

#include "tools-types.h"

#include "base/tile-manager.h"

#include "core/gimp.h"
#include "core/gimpchannel.h"
#include "core/gimpcontext.h"
#include "core/gimpdrawable-transform.h"
#include "core/gimpimage.h"
#include "core/gimpimage-mask.h"
#include "core/gimpimage-undo.h"
#include "core/gimpimage-undo-push.h"
#include "core/gimpitem-linked.h"
#include "core/gimplayer.h"
#include "core/gimptoolinfo.h"

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

#include "widgets/gimpdialogfactory.h"
#include "widgets/gimpviewabledialog.h"

#include "display/gimpdisplay.h"
#include "display/gimpprogress.h"

#ifdef __GNUC__
#warning FIXME #include "gui/gui-types.h"
#endif
#include "gui/gui-types.h"
#include "gui/info-dialog.h"

#include "gimptoolcontrol.h"
#include "gimptransformoptions.h"
#include "gimptransformtool.h"
#include "gimptransformtool-undo.h"

#include "gimp-intl.h"


#define HANDLE_SIZE 10


/*  local function prototypes  */

static void   gimp_transform_tool_init        (GimpTransformTool      *tool);
static void   gimp_transform_tool_class_init  (GimpTransformToolClass *tool);

static void   gimp_transform_tool_finalize         (GObject           *object);

static void   gimp_transform_tool_initialize       (GimpTool          *tool,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_control          (GimpTool          *tool,
                                                    GimpToolAction     action,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_button_press     (GimpTool          *tool,
                                                    GimpCoords        *coords,
                                                    guint32            time,
                                                    GdkModifierType    state,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_button_release   (GimpTool          *tool,
                                                    GimpCoords        *coords,
                                                    guint32            time,
                                                    GdkModifierType    state,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_motion           (GimpTool          *tool,
                                                    GimpCoords        *coords,
                                                    guint32            time,
                                                    GdkModifierType    state,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_modifier_key     (GimpTool          *tool,
                                                    GdkModifierType    key,
                                                    gboolean           press,
                                                    GdkModifierType    state,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_oper_update      (GimpTool          *tool,
                                                    GimpCoords        *coords,
                                                    GdkModifierType    state,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_cursor_update    (GimpTool          *tool,
                                                    GimpCoords        *coords,
                                                    GdkModifierType    state,
                                                    GimpDisplay       *gdisp);

static void   gimp_transform_tool_draw             (GimpDrawTool      *draw_tool);

static TileManager *
              gimp_transform_tool_real_transform   (GimpTransformTool *tr_tool,
                                                    GimpItem          *item,
                                                    GimpDisplay       *gdisp);

static void   gimp_transform_tool_halt             (GimpTransformTool *tr_tool);
static void   gimp_transform_tool_bounds           (GimpTransformTool *tr_tool,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_dialog           (GimpTransformTool *tr_tool);
static void   gimp_transform_tool_prepare          (GimpTransformTool *tr_tool,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_recalc           (GimpTransformTool *tr_tool,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_doit             (GimpTransformTool *tr_tool,
                                                    GimpDisplay       *gdisp);
static void   gimp_transform_tool_grid_recalc      (GimpTransformTool *tr_tool);

static void   transform_reset_callback             (GtkWidget         *widget,
                                                    GimpTransformTool *tr_tool);
static void   transform_cancel_callback            (GtkWidget         *widget,
                                                    GimpTransformTool *tr_tool);
static void   transform_ok_callback                (GtkWidget         *widget,
                                                    GimpTransformTool *tr_tool);

static void   gimp_transform_tool_notify_type   (GimpTransformOptions *options,
                                                 GParamSpec           *pspec,
                                                 GimpTransformTool    *tr_tool);
static void   gimp_transform_tool_notify_grid   (GimpTransformOptions *options,
                                                 GParamSpec           *pspec,
                                                 GimpTransformTool    *tr_tool);


static GimpDrawToolClass *parent_class = NULL;


GType
gimp_transform_tool_get_type (void)
{
  static GType tool_type = 0;

  if (! tool_type)
    {
      static const GTypeInfo tool_info =
      {
        sizeof (GimpTransformToolClass),
	(GBaseInitFunc) NULL,
	(GBaseFinalizeFunc) NULL,
	(GClassInitFunc) gimp_transform_tool_class_init,
	NULL,           /* class_finalize */
	NULL,           /* class_data     */
	sizeof (GimpTransformTool),
	0,              /* n_preallocs    */
	(GInstanceInitFunc) gimp_transform_tool_init,
      };

      tool_type = g_type_register_static (GIMP_TYPE_DRAW_TOOL,
					  "GimpTransformTool",
                                          &tool_info, 0);
    }

  return tool_type;
}

static void
gimp_transform_tool_class_init (GimpTransformToolClass *klass)
{
  GObjectClass      *object_class;
  GimpToolClass     *tool_class;
  GimpDrawToolClass *draw_class;

  object_class = G_OBJECT_CLASS (klass);
  tool_class   = GIMP_TOOL_CLASS (klass);
  draw_class   = GIMP_DRAW_TOOL_CLASS (klass);

  parent_class = g_type_class_peek_parent (klass);

  object_class->finalize     = gimp_transform_tool_finalize;

  tool_class->initialize     = gimp_transform_tool_initialize;
  tool_class->control        = gimp_transform_tool_control;
  tool_class->button_press   = gimp_transform_tool_button_press;
  tool_class->button_release = gimp_transform_tool_button_release;
  tool_class->motion         = gimp_transform_tool_motion;
  tool_class->modifier_key   = gimp_transform_tool_modifier_key;
  tool_class->oper_update    = gimp_transform_tool_oper_update;
  tool_class->cursor_update  = gimp_transform_tool_cursor_update;

  draw_class->draw           = gimp_transform_tool_draw;

  klass->dialog              = NULL;
  klass->prepare             = NULL;
  klass->motion              = NULL;
  klass->recalc              = NULL;
  klass->transform           = gimp_transform_tool_real_transform;
}

static void
gimp_transform_tool_init (GimpTransformTool *tr_tool)
{
  GimpTool *tool;
  gint      i;

  tool = GIMP_TOOL (tr_tool);

  gimp_tool_control_set_scroll_lock (tool->control, TRUE);
  gimp_tool_control_set_preserve    (tool->control, FALSE);

  tr_tool->function = TRANSFORM_CREATING;
  tr_tool->original = NULL;

  for (i = 0; i < TRAN_INFO_SIZE; i++)
    {
      tr_tool->trans_info[i]     = 0.0;
      tr_tool->old_trans_info[i] = 0.0;
    }

  gimp_matrix3_identity (&tr_tool->transform);

  tr_tool->use_grid         = TRUE;
  tr_tool->use_center       = TRUE;
  tr_tool->ngx              = 0;
  tr_tool->ngy              = 0;
  tr_tool->grid_coords      = NULL;
  tr_tool->tgrid_coords     = NULL;

  tr_tool->notify_connected = FALSE;
  tr_tool->type             = GIMP_TRANSFORM_TYPE_LAYER;
  tr_tool->direction        = GIMP_TRANSFORM_FORWARD;

  tr_tool->shell_desc       = NULL;
  tr_tool->progress_text    = _("Transforming...");
  tr_tool->info_dialog      = NULL;
}

static void
gimp_transform_tool_finalize (GObject *object)
{
  GimpTransformTool *tr_tool;

  tr_tool = GIMP_TRANSFORM_TOOL (object);

  if (tr_tool->original)
    {
      tile_manager_unref (tr_tool->original);
      tr_tool->original = NULL;
    }

  if (tr_tool->info_dialog)
    {
      info_dialog_free (tr_tool->info_dialog);
      tr_tool->info_dialog = NULL;
    }

  if (tr_tool->grid_coords)
    {
      g_free (tr_tool->grid_coords);
      tr_tool->grid_coords = NULL;
    }

  if (tr_tool->tgrid_coords)
    {
      g_free (tr_tool->tgrid_coords);
      tr_tool->tgrid_coords = NULL;
    }

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
gimp_transform_tool_initialize (GimpTool    *tool,
				GimpDisplay *gdisp)
{
  GimpTransformTool *tr_tool = GIMP_TRANSFORM_TOOL (tool);

  if (gdisp != tool->gdisp)
    {
      GimpDrawable *drawable = gimp_image_active_drawable (gdisp->gimage);
      gint          i;

      if (GIMP_IS_LAYER (drawable) &&
          gimp_layer_get_mask (GIMP_LAYER (drawable)))
        {
          g_message (_("Transformations do not work on\n"
                       "layers that contain layer masks."));
          return;
        }

      /*  Set the pointer to the active display  */
      tool->gdisp    = gdisp;
      tool->drawable = drawable;

      /*  Initialize the transform tool dialog */
      if (! tr_tool->info_dialog)
        gimp_transform_tool_dialog (tr_tool);

      /*  Find the transform bounds for some tools (like scale,
       *  perspective) that actually need the bounds for
       *  initializing
       */
      gimp_transform_tool_bounds (tr_tool, gdisp);

      gimp_transform_tool_prepare (tr_tool, gdisp);

      /*  Recalculate the transform tool  */
      gimp_transform_tool_recalc (tr_tool, gdisp);

      if (tr_tool->use_grid && ! tr_tool->notify_connected)
        {
          tr_tool->type =
            GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options)->type;
          tr_tool->direction =
            GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options)->direction;

          g_signal_connect_object (tool->tool_info->tool_options,
                                   "notify::type",
                                   G_CALLBACK (gimp_transform_tool_notify_type),
                                   tr_tool, 0);
          g_signal_connect_object (tool->tool_info->tool_options,
                                   "notify::direction",
                                   G_CALLBACK (gimp_transform_tool_notify_type),
                                   tr_tool, 0);
          g_signal_connect_object (tool->tool_info->tool_options,
                                   "notify::grid-type",
                                   G_CALLBACK (gimp_transform_tool_notify_grid),
                                   tr_tool, 0);
          g_signal_connect_object (tool->tool_info->tool_options,
                                   "notify::grid-size",
                                   G_CALLBACK (gimp_transform_tool_notify_grid),
                                   tr_tool, 0);

          tr_tool->notify_connected = TRUE;
        }

      /*  start drawing the bounding box and handles...  */
      gimp_draw_tool_start (GIMP_DRAW_TOOL (tool), gdisp);

      tr_tool->function = TRANSFORM_CREATING;

      /*  Save the current transformation info  */
      for (i = 0; i < TRAN_INFO_SIZE; i++)
	tr_tool->old_trans_info[i] = tr_tool->trans_info[i];
    }
}

static void
gimp_transform_tool_control (GimpTool       *tool,
			     GimpToolAction  action,
			     GimpDisplay    *gdisp)
{
  GimpTransformTool *tr_tool;

  tr_tool = GIMP_TRANSFORM_TOOL (tool);

  switch (action)
    {
    case PAUSE:
      break;

    case RESUME:
      gimp_transform_tool_recalc (tr_tool, gdisp);
      break;

    case HALT:
      gimp_transform_tool_halt (tr_tool);
      return; /* don't upchain */
      break;

    default:
      break;
    }

  GIMP_TOOL_CLASS (parent_class)->control (tool, action, gdisp);
}

static void
gimp_transform_tool_button_press (GimpTool        *tool,
                                  GimpCoords      *coords,
                                  guint32          time,
                                  GdkModifierType  state,
			          GimpDisplay     *gdisp)
{
  GimpTransformTool *tr_tool;

  tr_tool = GIMP_TRANSFORM_TOOL (tool);

  if (tr_tool->function == TRANSFORM_CREATING && tr_tool->use_grid)
    gimp_transform_tool_oper_update (tool, coords, state, gdisp);

  tr_tool->lastx = tr_tool->startx = coords->x;
  tr_tool->lasty = tr_tool->starty = coords->y;

  gimp_tool_control_activate (tool->control);
}

static void
gimp_transform_tool_button_release (GimpTool        *tool,
                                    GimpCoords      *coords,
                                    guint32          time,
			            GdkModifierType  state,
			            GimpDisplay     *gdisp)
{
  GimpTransformTool *tr_tool;
  gint               i;

  tr_tool = GIMP_TRANSFORM_TOOL (tool);

  /*  if we are creating, there is nothing to be done...exit  */
  if (tr_tool->function == TRANSFORM_CREATING && tr_tool->use_grid)
    return;

  /*  if the 3rd button isn't pressed, transform the selected mask  */
  if (! (state & GDK_BUTTON3_MASK))
    {
      /* Shift-clicking is another way to approve the transform  */
      if ((state & GDK_SHIFT_MASK) || ! tr_tool->use_grid)
	{
	  gimp_transform_tool_doit (tr_tool, gdisp);
	}
    }
  else
    {
      gimp_draw_tool_pause (GIMP_DRAW_TOOL (tool));

      /*  Restore the previous transformation info  */
      for (i = 0; i < TRAN_INFO_SIZE; i++)
	tr_tool->trans_info[i] = tr_tool->old_trans_info[i];

      /*  recalculate the tool's transformation matrix  */
      gimp_transform_tool_recalc (tr_tool, gdisp);

      gimp_draw_tool_resume (GIMP_DRAW_TOOL (tool));
    }

  gimp_tool_control_halt (tool->control);
}

static void
gimp_transform_tool_motion (GimpTool        *tool,
                            GimpCoords      *coords,
                            guint32          time,
		            GdkModifierType  state,
		            GimpDisplay     *gdisp)
{
  GimpTransformToolClass *tr_tool_class;
  GimpTransformTool      *tr_tool;

  tr_tool = GIMP_TRANSFORM_TOOL (tool);

  /*  if we are creating, there is nothing to be done so exit.  */
  if (tr_tool->function == TRANSFORM_CREATING || ! tr_tool->use_grid)
    return;

  gimp_draw_tool_pause (GIMP_DRAW_TOOL (tool));

  tr_tool->curx  = coords->x;
  tr_tool->cury  = coords->y;
  tr_tool->state = state;

  /*  recalculate the tool's transformation matrix  */
  tr_tool_class = GIMP_TRANSFORM_TOOL_GET_CLASS (tr_tool);

  if (tr_tool_class->motion)
    {
      tr_tool_class->motion (tr_tool, gdisp);

      if (tr_tool_class->recalc)
        tr_tool_class->recalc (tr_tool, gdisp);
    }

  tr_tool->lastx = tr_tool->curx;
  tr_tool->lasty = tr_tool->cury;

  gimp_draw_tool_resume (GIMP_DRAW_TOOL (tool));
}

static void
gimp_transform_tool_modifier_key (GimpTool        *tool,
                                  GdkModifierType  key,
                                  gboolean         press,
                                  GdkModifierType  state,
                                  GimpDisplay     *gdisp)
{
  GimpTransformOptions *options;

  options = GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options);

  if (key == GDK_CONTROL_MASK)
    {
      g_object_set (options,
                    "constrain-1", ! options->constrain_1,
                    NULL);
    }
  else if (key == GDK_MOD1_MASK)
    {
      g_object_set (options,
                    "constrain-2", ! options->constrain_2,
                    NULL);
    }
}

static void
gimp_transform_tool_oper_update (GimpTool        *tool,
                                 GimpCoords      *coords,
                                 GdkModifierType  state,
                                 GimpDisplay     *gdisp)
{
  GimpTransformTool *tr_tool;
  GimpDrawTool      *draw_tool;

  tr_tool   = GIMP_TRANSFORM_TOOL (tool);
  draw_tool = GIMP_DRAW_TOOL (tool);

  if (! tr_tool->use_grid)
    return;

  if (gdisp == tool->gdisp)
    {
      gdouble closest_dist;
      gdouble dist;

      closest_dist = gimp_draw_tool_calc_distance (draw_tool, gdisp,
                                                   coords->x, coords->y,
                                                   tr_tool->tx1, tr_tool->ty1);
      tr_tool->function = TRANSFORM_HANDLE_1;

      dist = gimp_draw_tool_calc_distance (draw_tool, gdisp,
                                           coords->x, coords->y,
                                           tr_tool->tx2, tr_tool->ty2);
      if (dist < closest_dist)
	{
	  closest_dist = dist;
	  tr_tool->function = TRANSFORM_HANDLE_2;
	}

      dist = gimp_draw_tool_calc_distance (draw_tool, gdisp,
                                           coords->x, coords->y,
                                           tr_tool->tx3, tr_tool->ty3);
      if (dist < closest_dist)
	{
	  closest_dist = dist;
	  tr_tool->function = TRANSFORM_HANDLE_3;
	}

      dist = gimp_draw_tool_calc_distance (draw_tool, gdisp,
                                           coords->x, coords->y,
                                           tr_tool->tx4, tr_tool->ty4);
      if (dist < closest_dist)
	{
	  closest_dist = dist;
	  tr_tool->function = TRANSFORM_HANDLE_4;
	}

      if (gimp_draw_tool_on_handle (draw_tool, gdisp,
                                    coords->x, coords->y,
                                    GIMP_HANDLE_CIRCLE,
                                    tr_tool->tcx, tr_tool->tcy,
                                    HANDLE_SIZE, HANDLE_SIZE,
                                    GTK_ANCHOR_CENTER,
                                    FALSE))
	{
	  tr_tool->function = TRANSFORM_HANDLE_CENTER;
	}
    }
}

static void
gimp_transform_tool_cursor_update (GimpTool        *tool,
                                   GimpCoords      *coords,
			           GdkModifierType  state,
			           GimpDisplay     *gdisp)
{
  GimpTransformTool    *tr_tool;
  GimpTransformOptions *options;

  tr_tool = GIMP_TRANSFORM_TOOL (tool);
  options = GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options);

  if (tr_tool->use_grid)
    {
      GdkCursorType      ctype     = GDK_TOP_LEFT_ARROW;
      GimpCursorModifier cmodifier = GIMP_CURSOR_MODIFIER_NONE;

      switch (options->type)
        {
        case GIMP_TRANSFORM_TYPE_LAYER:
          {
            GimpDrawable *drawable;

            drawable = gimp_image_active_drawable (gdisp->gimage);

            if (drawable)
              {
                if (GIMP_IS_LAYER (drawable) &&
                    gimp_layer_get_mask (GIMP_LAYER (drawable)))
                  {
                    ctype = GIMP_BAD_CURSOR;
                  }
                else if (gimp_display_coords_in_active_drawable (gdisp, coords))
                  {
                    if (gimp_image_mask_is_empty (gdisp->gimage) ||
                        gimp_image_mask_value (gdisp->gimage,
                                               coords->x, coords->y))
                      {
                        ctype = GIMP_MOUSE_CURSOR;
                      }
                  }
              }
          }
          break;

        case GIMP_TRANSFORM_TYPE_SELECTION:
          if (gimp_image_mask_is_empty (gdisp->gimage) ||
              gimp_image_mask_value (gdisp->gimage, coords->x, coords->y))
            {
              ctype = GIMP_MOUSE_CURSOR;
            }
          break;

        case GIMP_TRANSFORM_TYPE_PATH:
          if (gimp_image_get_active_vectors (gdisp->gimage))
            ctype = GIMP_MOUSE_CURSOR;
          else
            ctype = GIMP_BAD_CURSOR;
          break;
        }

      if (tr_tool->use_center && tr_tool->function == TRANSFORM_HANDLE_CENTER)
        {
          cmodifier = GIMP_CURSOR_MODIFIER_MOVE;
        }

      gimp_tool_control_set_cursor          (tool->control, ctype);
      gimp_tool_control_set_cursor_modifier (tool->control, cmodifier);
    }

  GIMP_TOOL_CLASS (parent_class)->cursor_update (tool, coords, state, gdisp);
}

static void
gimp_transform_tool_draw (GimpDrawTool *draw_tool)
{
  GimpTool             *tool;
  GimpTransformTool    *tr_tool;
  GimpTransformOptions *options;

  tr_tool = GIMP_TRANSFORM_TOOL (draw_tool);

  if (! tr_tool->use_grid)
    return;

  tool    = GIMP_TOOL (draw_tool);
  options = GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options);

  /*  draw the bounding box  */
  gimp_draw_tool_draw_line (draw_tool,
                            tr_tool->tx1, tr_tool->ty1,
                            tr_tool->tx2, tr_tool->ty2,
                            FALSE);
  gimp_draw_tool_draw_line (draw_tool,
                            tr_tool->tx2, tr_tool->ty2,
                            tr_tool->tx4, tr_tool->ty4,
                            FALSE);
  gimp_draw_tool_draw_line (draw_tool,
                            tr_tool->tx3, tr_tool->ty3,
                            tr_tool->tx4, tr_tool->ty4,
                            FALSE);
  gimp_draw_tool_draw_line (draw_tool,
                            tr_tool->tx3, tr_tool->ty3,
                            tr_tool->tx1, tr_tool->ty1,
                            FALSE);

  /*  Draw the grid (not for path transform since it looks ugly)  */

  if (tr_tool->type != GIMP_TRANSFORM_TYPE_PATH &&
      tr_tool->grid_coords                      &&
      tr_tool->tgrid_coords                     &&
      tr_tool->transform.coeff[0][0] >=  0.0    &&
      tr_tool->transform.coeff[1][1] >=  0.0    &&
      tr_tool->transform.coeff[1][0] >= -1.0    &&
      tr_tool->transform.coeff[0][1] >= -1.0)
    {
      gint gci, i, k;

      k = tr_tool->ngx + tr_tool->ngy;

      for (i = 0, gci = 0; i < k; i++, gci += 4)
	{
          gimp_draw_tool_draw_line (draw_tool,
                                    tr_tool->tgrid_coords[gci],
                                    tr_tool->tgrid_coords[gci + 1],
                                    tr_tool->tgrid_coords[gci + 2],
                                    tr_tool->tgrid_coords[gci + 3],
                                    FALSE);
	}
    }

  /*  draw the tool handles  */
  gimp_draw_tool_draw_handle (draw_tool,
                              GIMP_HANDLE_SQUARE,
                              tr_tool->tx1, tr_tool->ty1,
                              HANDLE_SIZE, HANDLE_SIZE,
                              GTK_ANCHOR_CENTER,
                              FALSE);
  gimp_draw_tool_draw_handle (draw_tool,
                              GIMP_HANDLE_SQUARE,
                              tr_tool->tx2, tr_tool->ty2,
                              HANDLE_SIZE, HANDLE_SIZE,
                              GTK_ANCHOR_CENTER,
                              FALSE);
  gimp_draw_tool_draw_handle (draw_tool,
                              GIMP_HANDLE_SQUARE,
                              tr_tool->tx3, tr_tool->ty3,
                              HANDLE_SIZE, HANDLE_SIZE,
                              GTK_ANCHOR_CENTER,
                              FALSE);
  gimp_draw_tool_draw_handle (draw_tool,
                              GIMP_HANDLE_SQUARE,
                              tr_tool->tx4, tr_tool->ty4,
                              HANDLE_SIZE, HANDLE_SIZE,
                              GTK_ANCHOR_CENTER,
                              FALSE);

  /*  draw the center  */
  if (tr_tool->use_center)
    {
      gimp_draw_tool_draw_handle (draw_tool,
                                  GIMP_HANDLE_FILLED_CIRCLE,
                                  tr_tool->tcx, tr_tool->tcy,
                                  HANDLE_SIZE, HANDLE_SIZE,
                                  GTK_ANCHOR_CENTER,
                                  FALSE);
    }

  if (tr_tool->type == GIMP_TRANSFORM_TYPE_PATH)
    {
      GimpVectors *vectors;
      GimpStroke  *stroke = NULL;
      GimpMatrix3  matrix = tr_tool->transform;

      vectors = gimp_image_get_active_vectors (tool->gdisp->gimage);

      if (vectors)
        {
          if (tr_tool->direction == GIMP_TRANSFORM_BACKWARD)
            gimp_matrix3_invert (&matrix);

          while ((stroke = gimp_vectors_stroke_get_next (vectors, stroke)))
            {
              GArray   *coords;
              gboolean  closed;
              gint      i;

              coords = gimp_stroke_interpolate (stroke, 1.0, &closed);

              if (coords)
                {
                  for (i = 0; i < coords->len; i++)
                    {
                      GimpCoords *curr = &g_array_index (coords, GimpCoords, i);

                      gimp_matrix3_transform_point (&matrix,
                                                    curr->x, curr->y,
                                                    &curr->x, &curr->y);
                    }

                  if (coords->len)
                    gimp_draw_tool_draw_strokes (draw_tool,
                                                 &g_array_index (coords,
                                                                 GimpCoords, 0),
                                                 coords->len, FALSE, FALSE);

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

static TileManager *
gimp_transform_tool_real_transform (GimpTransformTool *tr_tool,
                                    GimpItem          *active_item,
                                    GimpDisplay       *gdisp)
{
  GimpTool             *tool;
  GimpTransformOptions *options;
  GimpProgress         *progress;
  TileManager          *ret = NULL;

  tool    = GIMP_TOOL (tr_tool);
  options = GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options);

  if (tr_tool->info_dialog)
    gtk_widget_set_sensitive (GTK_WIDGET (tr_tool->info_dialog->shell), FALSE);

  progress = gimp_progress_start (gdisp, tr_tool->progress_text, FALSE,
                                  NULL, NULL);

  if (gimp_item_get_linked (active_item))
    gimp_item_linked_transform (active_item, &tr_tool->transform,
                                options->direction,
                                options->interpolation, options->clip,
                                progress ?
                                gimp_progress_update_and_flush : NULL,
                                progress);

  switch (options->type)
    {
    case GIMP_TRANSFORM_TYPE_LAYER:
    case GIMP_TRANSFORM_TYPE_SELECTION:
      {
        gboolean clip_result = options->clip;

        /*  always clip the selction and unfloated channels
         *  so they keep their size
         */
        if (GIMP_IS_CHANNEL (active_item) &&
            tile_manager_bpp (tr_tool->original) == 1)
          clip_result = TRUE;

        ret =
          gimp_drawable_transform_tiles_affine (GIMP_DRAWABLE (active_item),
                                                tr_tool->original,
                                                &tr_tool->transform,
                                                options->direction,
                                                options->interpolation,
                                                clip_result,
                                                progress ?
                                                gimp_progress_update_and_flush :
                                                NULL,
                                                progress);
      }
      break;

    case GIMP_TRANSFORM_TYPE_PATH:
      gimp_item_transform (active_item,
                           &tr_tool->transform,
                           options->direction,
                           options->interpolation,
                           options->clip,
                           progress ?
                           gimp_progress_update_and_flush :
                           NULL,
                           progress);
      break;
    }

  if (progress)
    gimp_progress_end (progress);

  return ret;
}

static void
gimp_transform_tool_doit (GimpTransformTool  *tr_tool,
		          GimpDisplay        *gdisp)
{
  GimpTool             *tool;
  GimpTransformOptions *options;
  GimpItem             *active_item = NULL;
  TileManager          *new_tiles;
  gboolean              new_layer;

  tool    = GIMP_TOOL (tr_tool);
  options = GIMP_TRANSFORM_OPTIONS (tool->tool_info->tool_options);

  switch (options->type)
    {
    case GIMP_TRANSFORM_TYPE_LAYER:
      active_item = (GimpItem *) gimp_image_active_drawable (gdisp->gimage);
      break;

    case GIMP_TRANSFORM_TYPE_SELECTION:
      active_item = (GimpItem *) gimp_image_get_mask (gdisp->gimage);
      break;

    case GIMP_TRANSFORM_TYPE_PATH:
      active_item = (GimpItem *) gimp_image_get_active_vectors (gdisp->gimage);
      break;
    }

  if (! active_item)
    return;

  gimp_set_busy (gdisp->gimage->gimp);

  /* undraw the tool before we muck around with the transform matrix */
  gimp_draw_tool_stop (GIMP_DRAW_TOOL (tr_tool));

  /*  We're going to dirty this image, but we want to keep the tool around  */
  gimp_tool_control_set_preserve (tool->control, TRUE);

  /*  Start a transform undo group  */
  gimp_image_undo_group_start (gdisp->gimage, GIMP_UNDO_GROUP_TRANSFORM,
                               tool->tool_info->blurb);

  /* With the old UI, if original is NULL, then this is the
   * first transformation. In the new UI, it is always so, right?
   */
  g_assert (tr_tool->original == NULL);

  /*  Copy the current selection to the transform tool's private
   *  selection pointer, so that the original source can be repeatedly
   *  modified.
   */
  tool->drawable = gimp_image_active_drawable (gdisp->gimage);

  switch (options->type)
    {
    case GIMP_TRANSFORM_TYPE_LAYER:
      tr_tool->original = gimp_drawable_transform_cut (tool->drawable,
                                                       &new_layer);
      break;

    case GIMP_TRANSFORM_TYPE_SELECTION:
      tr_tool->original = tile_manager_ref (GIMP_DRAWABLE (active_item)->tiles);
      tile_manager_set_offsets (tr_tool->original, 0, 0);
      break;

    case GIMP_TRANSFORM_TYPE_PATH:
      tr_tool->original = NULL;
      break;
    }

  /*  Send the request for the transformation to the tool...
   */
  new_tiles = GIMP_TRANSFORM_TOOL_GET_CLASS (tr_tool)->transform (tr_tool,
                                                                  active_item,
                                                                  gdisp);

  gimp_transform_tool_prepare (tr_tool, gdisp);
  gimp_transform_tool_recalc (tr_tool, gdisp);

  switch (options->type)
    {
    case GIMP_TRANSFORM_TYPE_LAYER:
      if (new_tiles)
        {
          /*  paste the new transformed image to the gimage...also implement
           *  undo...
           */
          /*  FIXME: we should check if the drawable is still valid  */
          gimp_drawable_transform_paste (tool->drawable,
                                         new_tiles,
                                         new_layer);
          tile_manager_unref (new_tiles);
        }
      break;

     case GIMP_TRANSFORM_TYPE_SELECTION:
      if (new_tiles)
        {
          gimp_image_mask_push_undo (gdisp->gimage, NULL);

          tile_manager_unref (GIMP_DRAWABLE (active_item)->tiles);
          GIMP_DRAWABLE (active_item)->tiles = new_tiles;

          GIMP_CHANNEL (active_item)->bounds_known = FALSE;

          gimp_image_mask_changed (gdisp->gimage);
        }

      tile_manager_unref (tr_tool->original);
      tr_tool->original = NULL;
      break;

    case GIMP_TRANSFORM_TYPE_PATH:
      /*  Nothing to be done  */
      break;
    }

  /*  Make a note of the new current drawable (since we may have
   *  a floating selection, etc now.
   */
  tool->drawable = gimp_image_active_drawable (gdisp->gimage);

  gimp_transform_tool_push_undo (gdisp->gimage, NULL,
                                 tool->ID,
                                 G_TYPE_FROM_INSTANCE (tool),
                                 tr_tool->old_trans_info,
                                 NULL);

  /*  push the undo group end  */
  gimp_image_undo_group_end (gdisp->gimage);

  /*  We're done dirtying the image, and would like to be restarted
   *  if the image gets dirty while the tool exists
   */
  gimp_tool_control_set_preserve (tool->control, FALSE);

  gimp_unset_busy (gdisp->gimage->gimp);

  gimp_image_flush (gdisp->gimage);

  gimp_transform_tool_halt (tr_tool);
}

void
gimp_transform_tool_transform_bounding_box (GimpTransformTool *tr_tool)
{
  g_return_if_fail (GIMP_IS_TRANSFORM_TOOL (tr_tool));

  gimp_matrix3_transform_point (&tr_tool->transform,
				tr_tool->x1, tr_tool->y1,
				&tr_tool->tx1, &tr_tool->ty1);
  gimp_matrix3_transform_point (&tr_tool->transform,
				tr_tool->x2, tr_tool->y1,
				&tr_tool->tx2, &tr_tool->ty2);
  gimp_matrix3_transform_point (&tr_tool->transform,
				tr_tool->x1, tr_tool->y2,
				&tr_tool->tx3, &tr_tool->ty3);
  gimp_matrix3_transform_point (&tr_tool->transform,
				tr_tool->x2, tr_tool->y2,
				&tr_tool->tx4, &tr_tool->ty4);

  gimp_matrix3_transform_point (&tr_tool->transform,
				tr_tool->cx, tr_tool->cy,
				&tr_tool->tcx, &tr_tool->tcy);

  if (tr_tool->grid_coords != NULL && tr_tool->tgrid_coords != NULL)
    {
      gint i, k;
      gint gci;

      gci = 0;
      k   = (tr_tool->ngx + tr_tool->ngy) * 2;

      for (i = 0; i < k; i++)
	{
	  gimp_matrix3_transform_point (&tr_tool->transform,
					tr_tool->grid_coords[gci],
					tr_tool->grid_coords[gci + 1],
					&tr_tool->tgrid_coords[gci],
					&tr_tool->tgrid_coords[gci + 1]);
	  gci += 2;
	}
    }
}

static void
gimp_transform_tool_halt (GimpTransformTool *tr_tool)
{
  GimpTool *tool = GIMP_TOOL (tr_tool);

  if (tr_tool->original)
    {
      tile_manager_unref (tr_tool->original);
      tr_tool->original = NULL;
    }

  /*  inactivate the tool  */
  tr_tool->function = TRANSFORM_CREATING;

  if (gimp_draw_tool_is_active (GIMP_DRAW_TOOL (tr_tool)))
    gimp_draw_tool_stop (GIMP_DRAW_TOOL (tr_tool));

  if (tr_tool->info_dialog)
    info_dialog_popdown (tr_tool->info_dialog);

  tool->gdisp    = NULL;
  tool->drawable = NULL;
}

static void
gimp_transform_tool_bounds (GimpTransformTool *tr_tool,
		            GimpDisplay       *gdisp)
{
  GimpTransformOptions *options;

  options =
    GIMP_TRANSFORM_OPTIONS (GIMP_TOOL (tr_tool)->tool_info->tool_options);

  /*  find the boundaries  */
  if (tr_tool->original)
    {
      tile_manager_get_offsets (tr_tool->original, &tr_tool->x1, &tr_tool->y1);

      tr_tool->x2 = tr_tool->x1 + tile_manager_width (tr_tool->original);
      tr_tool->y2 = tr_tool->y1 + tile_manager_height (tr_tool->