gimpcurvestool.c 47.3 KB
Newer Older
Elliot Lee's avatar
Elliot Lee committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * 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
16
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Elliot Lee's avatar
Elliot Lee committed
17
 */
Sven Neumann's avatar
Sven Neumann committed
18

19 20 21
#include "config.h"

#include <stdio.h>
22 23
#include <stdlib.h>
#include <string.h>
24

Sven Neumann's avatar
Sven Neumann committed
25 26
#include <gtk/gtk.h>

27
#include "libgimpmath/gimpmath.h"
28
#include "libgimpbase/gimpbase.h"
29
#include "libgimpwidgets/gimpwidgets.h"
30

Michael Natterer's avatar
Michael Natterer committed
31 32 33 34 35 36 37 38 39 40
#include "tools-types.h"

#include "base/gimphistogram.h"
#include "base/gimplut.h"

#include "core/gimpdrawable.h"
#include "core/gimpimage.h"

#include "widgets/gimpcursor.h"

41
#include "display/gimpdisplay.h"
42
#include "display/gimpdisplay-foreach.h"
43

Michael Natterer's avatar
Michael Natterer committed
44 45
#include "gimpcurvestool.h"
#include "tool_manager.h"
Sven Neumann's avatar
Sven Neumann committed
46

47
#include "app_procs.h"
48
#include "image_map.h"
49

50 51
#include "libgimp/gimpintl.h"

52

53 54 55 56 57 58
#define GRAPH          0x1
#define XRANGE_TOP     0x2
#define XRANGE_BOTTOM  0x4
#define YRANGE         0x8
#define DRAW          0x10
#define ALL           0xFF
Elliot Lee's avatar
Elliot Lee committed
59

60
/*  NB: take care when changing these values: make sure the curve[] array in
61
 *  gimpcurvestool.h is large enough.
62
 */
63 64 65 66 67 68
#define GRAPH_WIDTH    256
#define GRAPH_HEIGHT   256
#define XRANGE_WIDTH   256
#define XRANGE_HEIGHT   16
#define YRANGE_WIDTH    16
#define YRANGE_HEIGHT  256
Elliot Lee's avatar
Elliot Lee committed
69 70 71 72 73 74 75 76 77 78 79 80 81 82 83
#define RADIUS           3
#define MIN_DISTANCE     8

#define RANGE_MASK  GDK_EXPOSURE_MASK | \
                    GDK_ENTER_NOTIFY_MASK

#define GRAPH_MASK  GDK_EXPOSURE_MASK | \
		    GDK_POINTER_MOTION_MASK | \
		    GDK_POINTER_MOTION_HINT_MASK | \
                    GDK_ENTER_NOTIFY_MASK | \
		    GDK_BUTTON_PRESS_MASK | \
		    GDK_BUTTON_RELEASE_MASK | \
		    GDK_BUTTON1_MOTION_MASK


84
typedef gdouble CRMatrix[4][4];
85

Michael Natterer's avatar
Michael Natterer committed
86

Michael Natterer's avatar
Michael Natterer committed
87 88 89 90 91
/*  local function prototypes  */

static void   gimp_curves_tool_class_init     (GimpCurvesToolClass *klass);
static void   gimp_curves_tool_init           (GimpCurvesTool      *bc_tool);

92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121
static void   gimp_curves_tool_initialize     (GimpTool        *tool,
					       GimpDisplay     *gdisp);
static void   gimp_curves_tool_control        (GimpTool        *tool,
					       ToolAction       action,
					       GimpDisplay     *gdisp);
static void   gimp_curves_tool_button_press   (GimpTool        *tool,
                                               GimpCoords      *coords,
                                               guint32          time,
					       GdkModifierType  state,
					       GimpDisplay     *gdisp);
static void   gimp_curves_tool_button_release (GimpTool        *tool,
                                               GimpCoords      *coords,
                                               guint32          time,
					       GdkModifierType  state,
					       GimpDisplay     *gdisp);
static void   gimp_curves_tool_motion         (GimpTool        *tool,
                                               GimpCoords      *coords,
                                               guint32          time,
					       GdkModifierType  state,
					       GimpDisplay     *gdisp);

static void   curves_color_update             (GimpTool        *tool,
					       GimpDisplay     *gdisp,
					       GimpDrawable    *drawable,
					       gint             x,
					       gint             y);
static void   curves_add_point                (GimpDrawable    *drawable,
					       gint             x,
					       gint             y,
					       gint             cchan);
122 123 124

static CurvesDialog * curves_dialog_new   (void);

125
static void   curves_dialog_hide          (void);
126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176
static void   curves_update               (CurvesDialog   *cd,
					   gint            );
static void   curves_plot_curve           (CurvesDialog   *cd,
					   gint            ,
					   gint            ,
					   gint            ,
					   gint            );
static void   curves_preview              (CurvesDialog   *cd);

static void   curves_channel_callback     (GtkWidget      *widget,
					   gpointer        data);

static void   curves_smooth_callback      (GtkWidget      *widget,
					   gpointer        data);
static void   curves_free_callback        (GtkWidget      *widget,
					   gpointer        data);

static void   curves_channel_reset        (gint            );
static void   curves_reset_callback       (GtkWidget      *widget,
					   gpointer        data);
static void   curves_ok_callback          (GtkWidget      *widget,
					   gpointer        data);
static void   curves_cancel_callback      (GtkWidget      *widget,
					   gpointer        data);
static void   curves_load_callback        (GtkWidget      *widget,
					   gpointer        data);
static void   curves_save_callback        (GtkWidget      *widget,
					   gpointer        data);
static void   curves_preview_update       (GtkWidget      *widget,
					   gpointer        data);
static gint   curves_xrange_events        (GtkWidget      *widget,
					   GdkEvent       *event,
					   CurvesDialog   *cd);
static gint   curves_yrange_events        (GtkWidget      *widget,
					   GdkEvent       *event,
					   CurvesDialog   *cd);
static gint   curves_graph_events         (GtkWidget      *widget,
					   GdkEvent       *event,
					   CurvesDialog   *cd);
static void   curves_CR_compose           (CRMatrix        ,
					   CRMatrix        ,
					   CRMatrix        );

static void   file_dialog_create          (GtkWidget      *widget);
static void   file_dialog_ok_callback     (GtkWidget      *widget,
					   gpointer        data);
static void   file_dialog_cancel_callback (GtkWidget      *widget,
					   gpointer        data);

static gboolean  curves_read_from_file    (FILE           *f);
static void      curves_write_to_file     (FILE           *f);
177 178


Michael Natterer's avatar
Michael Natterer committed
179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194
static CurvesDialog * curves_dialog = NULL;

/*  the curves file dialog  */
static GtkWidget *file_dlg = NULL;
static gboolean   load_save;

static GtkWidget *channel_items[5];

static CRMatrix CR_basis =
{
  { -0.5,  1.5, -1.5,  0.5 },
  {  1.0, -2.5,  2.0, -0.5 },
  { -0.5,  0.0,  0.5,  0.0 },
  {  0.0,  1.0,  0.0,  0.0 },
};

195 196
static GimpImageMapToolClass *parent_class = NULL;

Michael Natterer's avatar
Michael Natterer committed
197

198
/*  public functions  */
Michael Natterer's avatar
Michael Natterer committed
199 200

void
201 202
gimp_curves_tool_register (Gimp                     *gimp,
                           GimpToolRegisterCallback  callback)
Michael Natterer's avatar
Michael Natterer committed
203
{
204 205 206 207 208 209 210 211 212 213
  (* callback) (gimp,
                GIMP_TYPE_CURVES_TOOL,
                NULL,
                FALSE,
                "gimp:curves_tool",
                _("Curves"),
                _("Adjust color curves"),
                N_("/Image/Colors/Curves..."), NULL,
                NULL, "tools/curves.html",
                GIMP_STOCK_TOOL_CURVES);
Michael Natterer's avatar
Michael Natterer committed
214 215
}

216
GType
Michael Natterer's avatar
Michael Natterer committed
217 218
gimp_curves_tool_get_type (void)
{
219
  static GType tool_type = 0;
Michael Natterer's avatar
Michael Natterer committed
220 221 222

  if (! tool_type)
    {
223
      static const GTypeInfo tool_info =
Michael Natterer's avatar
Michael Natterer committed
224 225
      {
        sizeof (GimpCurvesToolClass),
226 227 228 229 230 231 232 233
	(GBaseInitFunc) NULL,
	(GBaseFinalizeFunc) NULL,
	(GClassInitFunc) gimp_curves_tool_class_init,
	NULL,           /* class_finalize */
	NULL,           /* class_data     */
	sizeof (GimpCurvesTool),
	0,              /* n_preallocs    */
	(GInstanceInitFunc) gimp_curves_tool_init,
Michael Natterer's avatar
Michael Natterer committed
234 235
      };

236 237 238
      tool_type = g_type_register_static (GIMP_TYPE_IMAGE_MAP_TOOL,
					  "GimpCurvesTool", 
                                          &tool_info, 0);
Michael Natterer's avatar
Michael Natterer committed
239 240 241 242 243 244 245 246
    }

  return tool_type;
}

static void
gimp_curves_tool_class_init (GimpCurvesToolClass *klass)
{
247
  GimpToolClass *tool_class;
Michael Natterer's avatar
Michael Natterer committed
248

249
  tool_class = GIMP_TOOL_CLASS (klass);
Michael Natterer's avatar
Michael Natterer committed
250

251
  parent_class = g_type_class_peek_parent (klass);
Michael Natterer's avatar
Michael Natterer committed
252 253 254 255 256 257 258 259 260 261 262 263 264 265

  tool_class->initialize     = gimp_curves_tool_initialize;
  tool_class->control        = gimp_curves_tool_control;
  tool_class->button_press   = gimp_curves_tool_button_press;
  tool_class->button_release = gimp_curves_tool_button_release;
  tool_class->motion         = gimp_curves_tool_motion;
}

static void
gimp_curves_tool_init (GimpCurvesTool *bc_tool)
{
}

static void
Michael Natterer's avatar
Michael Natterer committed
266 267
gimp_curves_tool_initialize (GimpTool    *tool,
			     GimpDisplay *gdisp)
Michael Natterer's avatar
Michael Natterer committed
268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333
{
  gint i, j;

  if (! gdisp)
    {
      curves_dialog_hide ();
      return;
    }

  if (gimp_drawable_is_indexed (gimp_image_active_drawable (gdisp->gimage)))
    {
      g_message (_("Curves for indexed drawables cannot be adjusted."));
      return;
    }

  /*  The curves dialog  */
  if (!curves_dialog)
    {
      curves_dialog = curves_dialog_new ();
    }
     
  /*  Initialize the values  */
  curves_dialog->channel = GIMP_HISTOGRAM_VALUE;
  for (i = 0; i < 5; i++)
    for (j = 0; j < 256; j++)
      curves_dialog->curve[i][j] = j;
  
  for (i = 0; i < 5; i++)
    {
      curves_channel_reset (i);
    }

  curves_dialog->drawable  = gimp_image_active_drawable (gdisp->gimage);
  curves_dialog->color     = gimp_drawable_is_rgb (curves_dialog->drawable);
  curves_dialog->image_map = image_map_create (gdisp, curves_dialog->drawable);

  /* check for alpha channel */
  if (gimp_drawable_has_alpha (curves_dialog->drawable))
    gtk_widget_set_sensitive (channel_items[4], TRUE);
  else 
    gtk_widget_set_sensitive (channel_items[4], FALSE);
  
  /*  hide or show the channel menu based on image type  */
  if (curves_dialog->color)
    for (i = 0; i < 4; i++) 
       gtk_widget_set_sensitive (channel_items[i], TRUE);
  else 
    for (i = 1; i < 4; i++) 
      gtk_widget_set_sensitive (channel_items[i], FALSE);

  /* set the current selection */
  gtk_option_menu_set_history (GTK_OPTION_MENU (curves_dialog->channel_menu),
			       curves_dialog->channel);

  gimp_lut_setup (curves_dialog->lut, 
		  (GimpLutFunc) curves_lut_func,
                  (gpointer) curves_dialog, 
		  gimp_drawable_bytes (curves_dialog->drawable));

  if (!GTK_WIDGET_VISIBLE (curves_dialog->shell))
    gtk_widget_show (curves_dialog->shell);

  curves_update (curves_dialog, GRAPH | DRAW);
}

static void
Michael Natterer's avatar
Michael Natterer committed
334 335 336
gimp_curves_tool_control (GimpTool    *tool,
			  ToolAction   action,
			  GimpDisplay *gdisp)
Michael Natterer's avatar
Michael Natterer committed
337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358
{
  switch (action)
    {
    case PAUSE:
      break;

    case RESUME:
      break;

    case HALT:
      curves_dialog_hide ();
      break;

    default:
      break;
    }

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

static void
359 360 361 362 363
gimp_curves_tool_button_press (GimpTool        *tool,
                               GimpCoords      *coords,
                               guint32          time,
			       GdkModifierType  state,
			       GimpDisplay     *gdisp)
Michael Natterer's avatar
Michael Natterer committed
364 365 366 367 368 369 370 371 372
{
  GimpDrawable *drawable;

  drawable = gimp_image_active_drawable (gdisp->gimage);

  tool->gdisp = gdisp;

  if (drawable != tool->drawable)
    {
373
      tool->preserve = TRUE;
Michael Natterer's avatar
Michael Natterer committed
374
      image_map_abort (curves_dialog->image_map);
375
      tool->preserve = FALSE;
Michael Natterer's avatar
Michael Natterer committed
376 377 378 379 380 381 382 383 384 385

      tool->drawable = drawable;

      curves_dialog->drawable = drawable;
      curves_dialog->color = gimp_drawable_is_rgb (drawable);
      curves_dialog->image_map = image_map_create (gdisp, drawable);
    }

  tool->state = ACTIVE;

386
  curves_color_update (tool, gdisp, drawable, coords->x, coords->y);
Michael Natterer's avatar
Michael Natterer committed
387 388 389 390
  curves_update (curves_dialog, GRAPH | DRAW);
}

static void
391 392 393 394 395
gimp_curves_tool_button_release (GimpTool        *tool,
                                 GimpCoords      *coords,
                                 guint32          time,
				 GdkModifierType  state,
				 GimpDisplay     *gdisp)
Michael Natterer's avatar
Michael Natterer committed
396 397 398 399 400 401 402
{
  GimpDrawable *drawable;

  if (! curves_dialog || 
      ! (drawable = gimp_image_active_drawable (gdisp->gimage)))
     return;

403
  curves_color_update (tool, gdisp, drawable, coords->x, coords->y);
Michael Natterer's avatar
Michael Natterer committed
404

405
  if (state & GDK_SHIFT_MASK)
Michael Natterer's avatar
Michael Natterer committed
406
    {
407
      curves_add_point (drawable, coords->x, coords->y, curves_dialog->channel);
Michael Natterer's avatar
Michael Natterer committed
408 409
      curves_calculate_curve (curves_dialog);
    }
410
  else if (state & GDK_CONTROL_MASK)
Michael Natterer's avatar
Michael Natterer committed
411
    {
412 413 414 415 416
      curves_add_point (drawable, coords->x, coords->y, GIMP_HISTOGRAM_VALUE);
      curves_add_point (drawable, coords->x, coords->y, GIMP_HISTOGRAM_RED);
      curves_add_point (drawable, coords->x, coords->y, GIMP_HISTOGRAM_GREEN);
      curves_add_point (drawable, coords->x, coords->y, GIMP_HISTOGRAM_BLUE);
      curves_add_point (drawable, coords->x, coords->y, GIMP_HISTOGRAM_ALPHA);
Michael Natterer's avatar
Michael Natterer committed
417 418 419 420 421 422 423
      curves_calculate_curve (curves_dialog);
    }

  curves_update (curves_dialog, GRAPH | DRAW);
}

static void
424 425 426 427 428
gimp_curves_tool_motion (GimpTool        *tool,
                         GimpCoords      *coords,
                         guint32          time,
			 GdkModifierType  state,
			 GimpDisplay     *gdisp)
Michael Natterer's avatar
Michael Natterer committed
429 430 431 432 433 434 435
{
  GimpDrawable *drawable;

  if (! curves_dialog ||
      ! (drawable = gimp_image_active_drawable (gdisp->gimage)))
     return;

436
  curves_color_update (tool, gdisp, drawable, coords->x, coords->y);
Michael Natterer's avatar
Michael Natterer committed
437 438 439 440
  curves_update (curves_dialog, GRAPH | DRAW);
}


Elliot Lee's avatar
Elliot Lee committed
441 442
/*  curves machinery  */

443
gfloat
Manish Singh's avatar
Manish Singh committed
444
curves_lut_func (CurvesDialog *cd,
445 446 447
		 gint          nchannels,
		 gint          channel,
		 gfloat        value)
Elliot Lee's avatar
Elliot Lee committed
448
{
449 450
  gfloat  f;
  gint    index;
451
  gdouble inten;
452
  gint    j;
Elliot Lee's avatar
Elliot Lee committed
453

454 455 456 457
  if (nchannels == 1)
    j = 0;
  else
    j = channel + 1;
458

459
  inten = value;
460

Manish Singh's avatar
Manish Singh committed
461
  /* For color images this runs through the loop with j = channel +1
462 463 464 465 466 467 468 469 470 471 472 473 474 475 476
     the first time and j = 0 the second time */
  /* For bw images this runs through the loop with j = 0 the first and
     only time  */
  for (; j >= 0; j -= (channel + 1))
  {
    /* don't apply the overall curve to the alpha channel */
    if (j == 0 && (nchannels == 2 || nchannels == 4)
	&& channel == nchannels -1)
      return inten;

    if (inten < 0.0)
      inten = cd->curve[j][0]/255.0;
    else if (inten >= 1.0)
      inten = cd->curve[j][255]/255.0;
    else /* interpolate the curve */
Elliot Lee's avatar
Elliot Lee committed
477
    {
478 479 480 481
      index = floor(inten * 255.0);
      f = inten*255.0 - index;
      inten = ((1.0 - f) * cd->curve[j][index    ] + 
	       (      f) * cd->curve[j][index + 1] ) / 255.0;
Elliot Lee's avatar
Elliot Lee committed
482
    }
483 484
  }
  return inten;
Elliot Lee's avatar
Elliot Lee committed
485 486
}

BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
487
static void
488 489 490 491 492
curves_color_update (GimpTool       *tool,
                     GimpDisplay    *gdisp,
                     GimpDrawable   *drawable,
                     gint            x,
                     gint            y)
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
493
{
494 495 496 497
  guchar        *color;
  gint           offx;
  gint           offy;
  gint           maxval;
498 499 500
  gboolean       has_alpha;
  gboolean       is_indexed;
  GimpImageType  sample_type;
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
501

502
  if (!tool || tool->state != ACTIVE)
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
503 504
    return;

505
  gimp_drawable_offsets (drawable, &offx, &offy);
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
506 507 508 509

  x -= offx;
  y -= offy;

510
  if (!(color = image_map_get_color_at (curves_dialog->image_map, x, y)))
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
511 512
    return;

513
  sample_type = gimp_drawable_type (drawable);
514 515
  is_indexed  = gimp_drawable_is_indexed (drawable);
  has_alpha   = GIMP_IMAGE_TYPE_HAS_ALPHA (sample_type);
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
516

Michael Natterer's avatar
Michael Natterer committed
517 518 519
  curves_dialog->col_value[GIMP_HISTOGRAM_RED] = color[RED_PIX];
  curves_dialog->col_value[GIMP_HISTOGRAM_GREEN] = color[GREEN_PIX];
  curves_dialog->col_value[GIMP_HISTOGRAM_BLUE] = color[BLUE_PIX];
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
520 521 522

  if (has_alpha)
    {
Michael Natterer's avatar
Michael Natterer committed
523
      curves_dialog->col_value [GIMP_HISTOGRAM_ALPHA] = color[3];
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
524 525 526
    }

  if (is_indexed)
Michael Natterer's avatar
Michael Natterer committed
527
    curves_dialog->col_value [GIMP_HISTOGRAM_ALPHA] = color[4];
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
528

529
  maxval = MAX (color[RED_PIX], color[GREEN_PIX]);
Michael Natterer's avatar
Michael Natterer committed
530
  curves_dialog->col_value[GIMP_HISTOGRAM_VALUE] = MAX (maxval, color[BLUE_PIX]);
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
531

532
  g_free (color);
533
}
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
534

535
static void
536 537 538 539
curves_add_point (GimpDrawable *drawable,
		  gint          x,
		  gint          y,
		  gint          cchan)
540 541
{
  /* Add point onto the curve */
542 543 544 545
  gint closest_point = 0;
  gint distance;
  gint curvex;
  gint i;
546

547
  switch (curves_dialog->curve_type[cchan])
548
    {
549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571
    case SMOOTH:
      curvex = curves_dialog->col_value[cchan];
      distance = G_MAXINT;
      for (i = 0; i < 17; i++)
	{
	  if (curves_dialog->points[cchan][i][0] != -1)
	    if (abs (curvex - curves_dialog->points[cchan][i][0]) < distance)
	      {
		distance = abs (curvex - curves_dialog->points[cchan][i][0]);
		closest_point = i;
	      }
	}
      
      if (distance > MIN_DISTANCE)
	closest_point = (curvex + 8) / 16;
      
      curves_dialog->points[cchan][closest_point][0] = curvex;
      curves_dialog->points[cchan][closest_point][1] = curves_dialog->curve[cchan][curvex];
      break;
      
    case GFREE:
      curves_dialog->curve[cchan][x] = 255 - y;
      break;
572
    }
Elliot Lee's avatar
Elliot Lee committed
573 574 575
}

void
576
curves_free (void)
Elliot Lee's avatar
Elliot Lee committed
577
{
578 579
  GimpTool *active_tool;

Elliot Lee's avatar
Elliot Lee committed
580 581 582 583
  if (curves_dialog)
    {
      if (curves_dialog->image_map)
	{
584 585
	  active_tool = tool_manager_get_active (the_gimp);

586
	  active_tool->preserve = TRUE;
Elliot Lee's avatar
Elliot Lee committed
587
	  image_map_abort (curves_dialog->image_map);
588
	  active_tool->preserve = FALSE;
589

Elliot Lee's avatar
Elliot Lee committed
590 591
	  curves_dialog->image_map = NULL;
	}
592

593 594
      gtk_widget_destroy (curves_dialog->shell);

Elliot Lee's avatar
Elliot Lee committed
595
      if (curves_dialog->pixmap)
Sven Neumann's avatar
Sven Neumann committed
596
	gdk_drawable_unref (curves_dialog->pixmap);
597

598 599 600 601 602 603 604 605 606 607
      if (curves_dialog->cursor_layout)
        g_object_unref (curves_dialog->cursor_layout);
      if (curves_dialog->xpos_layout)
        g_object_unref (curves_dialog->xpos_layout);

      if (curves_dialog->lut)
        gimp_lut_free (curves_dialog->lut);

      g_free (curves_dialog);
      curves_dialog = NULL;
Elliot Lee's avatar
Elliot Lee committed
608 609 610
    }
}

611 612 613
/*******************/
/*  Curves dialog  */
/*******************/
Elliot Lee's avatar
Elliot Lee committed
614

615
static CurvesDialog *
616
curves_dialog_new (void)
Elliot Lee's avatar
Elliot Lee committed
617 618 619 620
{
  CurvesDialog *cd;
  GtkWidget *vbox;
  GtkWidget *hbox;
621
  GtkWidget *hbbox;
Elliot Lee's avatar
Elliot Lee committed
622 623 624 625 626
  GtkWidget *label;
  GtkWidget *frame;
  GtkWidget *toggle;
  GtkWidget *channel_hbox;
  GtkWidget *table;
627
  GtkWidget *button;
628
  gint i, j;
629

630
  cd = g_new (CurvesDialog, 1);
631 632 633 634 635
  cd->preview       = TRUE;
  cd->pixmap        = NULL;
  cd->xpos_layout   = NULL;
  cd->cursor_layout = NULL;
  cd->channel       = GIMP_HISTOGRAM_VALUE;
636 637 638 639

  for (i = 0; i < 5; i++)
    cd->curve_type[i] = SMOOTH;

640 641 642
  for (i = 0; i < 5; i++)
    for (j = 0; j < 256; j++)
      cd->curve[i][j] = j;
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
643

644
  for (i = 0; i < (sizeof (cd->col_value) / sizeof (cd->col_value[0])); i++)
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
645 646
    cd->col_value[i] = 0;

647
  cd->lut = gimp_lut_new ();
Elliot Lee's avatar
Elliot Lee committed
648 649

  /*  The shell and main vbox  */
650
  cd->shell = gimp_dialog_new (_("Curves"), "curves",
Michael Natterer's avatar
Michael Natterer committed
651
			       tool_manager_help_func, NULL,
652 653 654
			       GTK_WIN_POS_NONE,
			       FALSE, TRUE, FALSE,

655
			       GTK_STOCK_OK, curves_ok_callback,
656
			       cd, NULL, NULL, TRUE, FALSE,
657
			       GIMP_STOCK_RESET, curves_reset_callback,
658
			       cd, NULL, NULL, FALSE, FALSE,
659
			       GTK_STOCK_CANCEL, curves_cancel_callback,
660
			       cd, NULL, NULL, FALSE, TRUE,
661 662

			       NULL);
Elliot Lee's avatar
Elliot Lee committed
663

664 665
  vbox = gtk_vbox_new (FALSE, 4);
  gtk_container_set_border_width (GTK_CONTAINER (vbox), 4);
666
  gtk_container_add (GTK_CONTAINER (GTK_DIALOG (cd->shell)->vbox), vbox);
Elliot Lee's avatar
Elliot Lee committed
667 668

  /*  The option menu for selecting channels  */
669
  channel_hbox = gtk_hbox_new (FALSE, 4);
Elliot Lee's avatar
Elliot Lee committed
670 671
  gtk_box_pack_start (GTK_BOX (vbox), channel_hbox, FALSE, FALSE, 0);

672
  label = gtk_label_new (_("Modify Curves for Channel:"));
Elliot Lee's avatar
Elliot Lee committed
673 674
  gtk_box_pack_start (GTK_BOX (channel_hbox), label, FALSE, FALSE, 0);

675
  cd->channel_menu = gimp_option_menu_new2
676 677 678 679
    (FALSE,
     G_CALLBACK (curves_channel_callback),
     cd,
     GINT_TO_POINTER (cd->channel),
680

681 682 683 684 685
     _("Value"), GINT_TO_POINTER (GIMP_HISTOGRAM_VALUE), &channel_items[0],
     _("Red"),   GINT_TO_POINTER (GIMP_HISTOGRAM_RED),   &channel_items[1],
     _("Green"), GINT_TO_POINTER (GIMP_HISTOGRAM_GREEN), &channel_items[2],
     _("Blue"),  GINT_TO_POINTER (GIMP_HISTOGRAM_BLUE),  &channel_items[3],
     _("Alpha"), GINT_TO_POINTER (GIMP_HISTOGRAM_ALPHA), &channel_items[4],
686 687 688

     NULL);

Elliot Lee's avatar
Elliot Lee committed
689 690 691 692 693 694 695 696
  gtk_box_pack_start (GTK_BOX (channel_hbox), cd->channel_menu, FALSE, FALSE, 2);

  gtk_widget_show (label);
  gtk_widget_show (cd->channel_menu);
  gtk_widget_show (channel_hbox);

  /*  The table for the yrange and the graph  */
  table = gtk_table_new (2, 2, FALSE);
697 698
  gtk_table_set_col_spacings (GTK_TABLE (table), 2);
  gtk_table_set_row_spacings (GTK_TABLE (table), 2);
Elliot Lee's avatar
Elliot Lee committed
699 700 701 702 703 704 705 706
  gtk_box_pack_start (GTK_BOX (vbox), table, FALSE, FALSE, 0);

  /*  The range drawing area  */
  frame = gtk_frame_new (NULL);
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
  gtk_table_attach (GTK_TABLE (table), frame, 0, 1, 0, 1,
		    GTK_EXPAND, GTK_EXPAND, 0, 0);

707
  cd->yrange = gtk_preview_new (GTK_PREVIEW_COLOR);
Elliot Lee's avatar
Elliot Lee committed
708 709
  gtk_preview_size (GTK_PREVIEW (cd->yrange), YRANGE_WIDTH, YRANGE_HEIGHT);
  gtk_widget_set_events (cd->yrange, RANGE_MASK);
710 711
  gtk_container_add (GTK_CONTAINER (frame), cd->yrange);

712 713 714
  g_signal_connect (G_OBJECT (cd->yrange), "event",
		    G_CALLBACK (curves_yrange_events),
		    cd);
715

Elliot Lee's avatar
Elliot Lee committed
716 717 718 719 720 721 722
  gtk_widget_show (cd->yrange);
  gtk_widget_show (frame);

  /*  The curves graph  */
  frame = gtk_frame_new (NULL);
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
  gtk_table_attach (GTK_TABLE (table), frame, 1, 2, 0, 1,
723 724
		    GTK_SHRINK | GTK_FILL,
		    GTK_SHRINK | GTK_FILL, 0, 0);
Elliot Lee's avatar
Elliot Lee committed
725 726 727 728 729 730

  cd->graph = gtk_drawing_area_new ();
  gtk_drawing_area_size (GTK_DRAWING_AREA (cd->graph),
			 GRAPH_WIDTH + RADIUS * 2,
			 GRAPH_HEIGHT + RADIUS * 2);
  gtk_widget_set_events (cd->graph, GRAPH_MASK);
731 732
  gtk_container_add (GTK_CONTAINER (frame), cd->graph);

733 734 735
  g_signal_connect (G_OBJECT (cd->graph), "event",
		    G_CALLBACK (curves_graph_events),
		    cd);
736

Elliot Lee's avatar
Elliot Lee committed
737 738 739 740 741 742 743 744 745
  gtk_widget_show (cd->graph);
  gtk_widget_show (frame);

  /*  The range drawing area  */
  frame = gtk_frame_new (NULL);
  gtk_frame_set_shadow_type (GTK_FRAME (frame), GTK_SHADOW_ETCHED_IN);
  gtk_table_attach (GTK_TABLE (table), frame, 1, 2, 1, 2,
		    GTK_EXPAND, GTK_EXPAND, 0, 0);

746
  cd->xrange = gtk_preview_new (GTK_PREVIEW_COLOR);
Elliot Lee's avatar
Elliot Lee committed
747 748
  gtk_preview_size (GTK_PREVIEW (cd->xrange), XRANGE_WIDTH, XRANGE_HEIGHT);
  gtk_widget_set_events (cd->xrange, RANGE_MASK);
749 750
  gtk_container_add (GTK_CONTAINER (frame), cd->xrange);

751 752 753
  g_signal_connect (G_OBJECT (cd->xrange), "event",
		    G_CALLBACK (curves_xrange_events),
		    cd);
754

Elliot Lee's avatar
Elliot Lee committed
755 756 757 758 759
  gtk_widget_show (cd->xrange);
  gtk_widget_show (frame);
  gtk_widget_show (table);

  /*  Horizontal box for preview  */
760
  hbox = gtk_hbox_new (FALSE, 4);
761
  gtk_box_pack_end (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
Elliot Lee's avatar
Elliot Lee committed
762 763

  /*  The option menu for selecting the drawing method  */
764
  label = gtk_label_new (_("Curve Type:"));
Elliot Lee's avatar
Elliot Lee committed
765
  gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
766
  gtk_widget_show (label);
Elliot Lee's avatar
Elliot Lee committed
767

768 769
  cd->curve_type_menu = gimp_option_menu_new
    (FALSE,
Elliot Lee's avatar
Elliot Lee committed
770

771 772 773 774 775
     _("Smooth"), curves_smooth_callback, cd, NULL, NULL, TRUE,
     _("Free"),   curves_free_callback,   cd, NULL, NULL, FALSE,

     NULL);
  gtk_box_pack_start (GTK_BOX (hbox), cd->curve_type_menu, FALSE, FALSE, 2);
776
  gtk_widget_show (cd->curve_type_menu);
777

Elliot Lee's avatar
Elliot Lee committed
778 779 780
  gtk_widget_show (hbox);

  /*  The preview toggle  */
781
  toggle = gtk_check_button_new_with_label (_("Preview"));
782
  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (toggle), cd->preview);
783 784
  gtk_box_pack_end (GTK_BOX (hbox), toggle, FALSE, FALSE, 0);

785 786 787
  g_signal_connect (G_OBJECT (toggle), "toggled",
		    G_CALLBACK (curves_preview_update),
		    cd);
Elliot Lee's avatar
Elliot Lee committed
788 789 790 791

  gtk_widget_show (toggle);
  gtk_widget_show (hbox);

792 793 794 795 796 797 798 799 800 801 802
  /*  Horizontal button box for load / save  */
  hbbox = gtk_hbutton_box_new ();
  gtk_button_box_set_spacing (GTK_BUTTON_BOX (hbbox), 4);
  gtk_button_box_set_layout (GTK_BUTTON_BOX (hbbox), GTK_BUTTONBOX_SPREAD);
  gtk_box_pack_end (GTK_BOX (vbox), hbbox, FALSE, FALSE, 0);

  button = gtk_button_new_with_label (_("Load"));
  GTK_WIDGET_SET_FLAGS (button, GTK_CAN_DEFAULT);
  gtk_box_pack_start (GTK_BOX (hbbox), button, FALSE, FALSE, 0);
  gtk_widget_show (button);

803 804 805 806
  g_signal_connect (G_OBJECT (button), "clicked",
		    G_CALLBACK (curves_load_callback),
		    cd->shell);

807 808 809 810 811
  button = gtk_button_new_with_label (_("Save"));
  GTK_WIDGET_SET_FLAGS (button, GTK_CAN_DEFAULT);
  gtk_box_pack_start (GTK_BOX (hbbox), button, FALSE, FALSE, 0);
  gtk_widget_show (button);

812 813 814 815
  g_signal_connect (G_OBJECT (button), "clicked",
		    G_CALLBACK (curves_save_callback),
		    cd->shell);

816
  gtk_widget_show (hbbox);
Elliot Lee's avatar
Elliot Lee committed
817 818 819 820 821
  gtk_widget_show (vbox);

  return cd;
}

822 823 824 825 826 827 828
static void
curves_dialog_hide (void)
{
  if (curves_dialog)
    curves_cancel_callback (NULL, (gpointer) curves_dialog);
}

829
static void
830 831 832
curve_print_loc (CurvesDialog *cd,
		 gint          xpos,
		 gint          ypos)
833
{
834
  gchar buf[32];
835

836
  if (!cd->cursor_layout)
837
    {
838 839 840 841
      cd->cursor_layout = gtk_widget_create_pango_layout (cd->graph,
                                                          "x:888 y:888");
      pango_layout_get_pixel_extents (cd->cursor_layout, 
                                      NULL, &cd->cursor_rect);
842 843
    }
  
844
  if (xpos >= 0 && xpos <= 255 && ypos >=0 && ypos <= 255)
845 846 847
    {
      gdk_draw_rectangle (cd->graph->window, 
			  cd->graph->style->bg_gc[GTK_STATE_ACTIVE],
848 849 850 851 852
			  TRUE, 
                          RADIUS*2 + 2, 
                          RADIUS*2 + 2, 
			  cd->cursor_rect.width  + 4,
			  cd->cursor_rect.height + 5);
853 854 855

      gdk_draw_rectangle (cd->graph->window, 
			  cd->graph->style->black_gc,
856 857 858 859 860 861 862 863 864 865 866 867 868
			  FALSE, 
                          RADIUS*2 + 2, 
                          RADIUS*2 + 2, 
			  cd->cursor_rect.width  + 3, 
			  cd->cursor_rect.height + 4);
      
      g_snprintf (buf, sizeof (buf), "x:%3d y:%3d",xpos, ypos);
      pango_layout_set_text (cd->cursor_layout, buf, 11);
      gdk_draw_layout (cd->graph->window, 
                       cd->graph->style->black_gc,
		       RADIUS*2 + 4 + cd->cursor_rect.x,
		       RADIUS*2 + 5 + cd->cursor_rect.y,
		       cd->cursor_layout);
869 870 871
    }
}

872
/* TODO: preview alpha channel stuff correctly.  -- austin, 20/May/99 */
Elliot Lee's avatar
Elliot Lee committed
873 874
static void
curves_update (CurvesDialog *cd,
875
	       gint          update)
Elliot Lee's avatar
Elliot Lee committed
876 877
{
  GdkRectangle area;
878 879 880
  gint   i, j;
  gchar  buf[32];
  gint   offset;
881
  gint   height;
882 883 884 885 886 887
  gint   sel_channel;
  
  if(cd->color) {
    sel_channel = cd->channel;
  } else {
    if(cd->channel == 2)
Michael Natterer's avatar
Michael Natterer committed
888
      sel_channel = GIMP_HISTOGRAM_ALPHA;
889
    else
Michael Natterer's avatar
Michael Natterer committed
890
      sel_channel = GIMP_HISTOGRAM_VALUE;
891 892
  }

Elliot Lee's avatar
Elliot Lee committed
893 894
  if (update & XRANGE_TOP)
    {
895
      guchar buf[XRANGE_WIDTH * 3];
896

897
      switch (sel_channel)
898
	{
Michael Natterer's avatar
Michael Natterer committed
899 900
	case GIMP_HISTOGRAM_VALUE:
	case GIMP_HISTOGRAM_ALPHA:
901
	  for (i = 0; i < XRANGE_HEIGHT / 2; i++)
902
	    {
903
	      for (j = 0; j < XRANGE_WIDTH ; j++)
904
		{
905 906 907
		  buf[j*3+0] = cd->curve[sel_channel][j];
		  buf[j*3+1] = cd->curve[sel_channel][j];
		  buf[j*3+2] = cd->curve[sel_channel][j];
908
		}
909 910
	      gtk_preview_draw_row (GTK_PREVIEW (cd->xrange),
				    buf, 0, i, XRANGE_WIDTH);
911
	    }
912 913
	  break;

Michael Natterer's avatar
Michael Natterer committed
914 915 916
	case GIMP_HISTOGRAM_RED:
	case GIMP_HISTOGRAM_GREEN:
	case GIMP_HISTOGRAM_BLUE:
917
	  {
918
	    for (i = 0; i < XRANGE_HEIGHT / 2; i++)
919
	      {
920 921
		for (j = 0; j < XRANGE_WIDTH; j++)
		  {
Michael Natterer's avatar
Michael Natterer committed
922 923 924
		    buf[j*3+0] = cd->curve[GIMP_HISTOGRAM_RED][j];
		    buf[j*3+1] = cd->curve[GIMP_HISTOGRAM_GREEN][j];
		    buf[j*3+2] = cd->curve[GIMP_HISTOGRAM_BLUE][j];
925 926 927
		  }
		gtk_preview_draw_row (GTK_PREVIEW (cd->xrange),
				      buf, 0, i, XRANGE_WIDTH);
928
	      }
929
	    break;
930 931
	  }

932
	default:
933 934 935
	  g_warning ("unknown channel type %d, can't happen!?!?",
		     cd->channel);
	  break;
936
	}
Elliot Lee's avatar
Elliot Lee committed
937 938 939 940 941 942 943 944 945 946 947 948

      if (update & DRAW)
	{
	  area.x = 0;
	  area.y = 0;
	  area.width = XRANGE_WIDTH;
	  area.height = XRANGE_HEIGHT / 2;
	  gtk_widget_draw (cd->xrange, &area);
	}
    }
  if (update & XRANGE_BOTTOM)
    {
949
      guchar buf[XRANGE_WIDTH * 3];
Elliot Lee's avatar
Elliot Lee committed
950 951

      for (i = 0; i < XRANGE_WIDTH; i++)
952 953 954 955 956
      {
	buf[i*3+0] = i;
	buf[i*3+1] = i;
	buf[i*3+2] = i;
      }
Elliot Lee's avatar
Elliot Lee committed
957 958 959 960 961 962 963 964 965 966 967 968 969 970 971

      for (i = XRANGE_HEIGHT / 2; i < XRANGE_HEIGHT; i++)
	gtk_preview_draw_row (GTK_PREVIEW (cd->xrange), buf, 0, i, XRANGE_WIDTH);

      if (update & DRAW)
	{
	  area.x = 0;
	  area.y = XRANGE_HEIGHT / 2;
	  area.width = XRANGE_WIDTH;
	  area.height = XRANGE_HEIGHT / 2;
	  gtk_widget_draw (cd->xrange, &area);
	}
    }
  if (update & YRANGE)
    {
972 973
      guchar buf[YRANGE_WIDTH * 3];
      guchar pix[3];
Elliot Lee's avatar
Elliot Lee committed
974 975 976

      for (i = 0; i < YRANGE_HEIGHT; i++)
	{
977
	  switch (sel_channel)
978
	    {
Michael Natterer's avatar
Michael Natterer committed
979 980
	    case GIMP_HISTOGRAM_VALUE:
	    case GIMP_HISTOGRAM_ALPHA:
981 982 983
	      pix[0] = pix[1] = pix[2] = (255 - i);
	      break;

Michael Natterer's avatar
Michael Natterer committed
984 985 986
	    case GIMP_HISTOGRAM_RED:
	    case GIMP_HISTOGRAM_GREEN:
	    case GIMP_HISTOGRAM_BLUE:
987
	      pix[0] = pix[1] = pix[2] = 0;
988
	      pix[sel_channel - 1] = (255 - i);
989 990
	      break;

991
	    default:
992 993 994
	      g_warning ("unknown channel type %d, can't happen!?!?",
			 cd->channel);
	      break;
995
	    }
996 997

	  for (j = 0; j < YRANGE_WIDTH * 3; j++)
998
	    buf[j] = pix[j%3];
Elliot Lee's avatar
Elliot Lee committed
999

1000 1001
	  gtk_preview_draw_row (GTK_PREVIEW (cd->yrange),
				buf, 0, i, YRANGE_WIDTH);
Elliot Lee's avatar
Elliot Lee committed
1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012
	}

      if (update & DRAW)
	gtk_widget_draw (cd->yrange, NULL);
    }
  if ((update & GRAPH) && (update & DRAW) && cd->pixmap != NULL)
    {
      GdkPoint points[256];

      /*  Clear the pixmap  */
      gdk_draw_rectangle (cd->pixmap, cd->graph->style->bg_gc[GTK_STATE_NORMAL],
1013 1014
			  TRUE, 0, 0,
			  GRAPH_WIDTH + RADIUS * 2, GRAPH_HEIGHT + RADIUS * 2);
Elliot Lee's avatar
Elliot Lee committed
1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035

      /*  Draw the grid lines  */
      for (i = 0; i < 5; i++)
	{
	  gdk_draw_line (cd->pixmap, cd->graph->style->dark_gc[GTK_STATE_NORMAL],
			 RADIUS, i * (GRAPH_HEIGHT / 4) + RADIUS,
			 GRAPH_WIDTH + RADIUS, i * (GRAPH_HEIGHT / 4) + RADIUS);
	  gdk_draw_line (cd->pixmap, cd->graph->style->dark_gc[GTK_STATE_NORMAL],
			 i * (GRAPH_WIDTH / 4) + RADIUS, RADIUS,
			 i * (GRAPH_WIDTH / 4) + RADIUS, GRAPH_HEIGHT + RADIUS);
	}

      /*  Draw the curve  */
      for (i = 0; i < 256; i++)
	{
	  points[i].x = i + RADIUS;
	  points[i].y = 255 - cd->curve[cd->channel][i] + RADIUS;
	}
      gdk_draw_points (cd->pixmap, cd->graph->style->black_gc, points, 256);

      /*  Draw the points  */
1036
      if (cd->curve_type[cd->channel] == SMOOTH)
Elliot Lee's avatar
Elliot Lee committed
1037 1038 1039 1040 1041 1042 1043 1044 1045
	for (i = 0; i < 17; i++)
	  {
	    if (cd->points[cd->channel][i][0] != -1)
	      gdk_draw_arc (cd->pixmap, cd->graph->style->black_gc, TRUE,
			    cd->points[cd->channel][i][0],
			    255 - cd->points[cd->channel][i][1],
			    RADIUS * 2, RADIUS * 2, 0, 23040);
	  }

1046
      /* draw the color line */
1047
      gdk_draw_line (cd->pixmap, cd->graph->style->black_gc,
1048 1049
		     cd->col_value[sel_channel]+RADIUS,RADIUS,
		     cd->col_value[sel_channel]+RADIUS,GRAPH_HEIGHT + RADIUS);
BST 1999 Andy Thomas's avatar
BST 1999 Andy Thomas committed
1050

1051
      /* and xpos indicator */
1052
      g_snprintf (buf, sizeof (buf), "x:%d",cd->col_value[sel_channel]);
1053 1054 1055 1056 1057 1058

      if (!cd->xpos_layout)
        cd->xpos_layout = gtk_widget_create_pango_layout (cd->graph, buf);
      else
        pango_layout_set_text (cd->xpos_layout, buf, -1);

1059
      if ((cd->col_value[sel_channel]+RADIUS) < 127)
1060 1061 1062 1063 1064
	{
	  offset = RADIUS + 4;
	}
      else
	{
1065 1066
          pango_layout_get_pixel_size (cd->xpos_layout, &offset, &height);
          offset = - (offset + 2);
1067 1068
	}

1069
      gdk_draw_layout (cd->pixmap,
1070
		       cd->graph->style->black_gc,
1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
		       cd->col_value[sel_channel] + offset,
		       GRAPH_HEIGHT - height - 2,
		       cd->xpos_layout);

      gdk_draw_drawable (cd->graph->window, 
                         cd->graph->style->black_gc, 
                         cd->pixmap,
			 0, 0, 
                         0, 0, 
                         GRAPH_WIDTH + RADIUS * 2, GRAPH_HEIGHT + RADIUS * 2);
Elliot Lee's avatar
Elliot Lee committed
1081 1082 1083 1084 1085
    }
}

static void
curves_plot_curve (CurvesDialog *cd,
1086 1087 1088 1089
		   gint          p1,
		   gint          p2,
		   gint          p3,
		   gint          p4)
Elliot Lee's avatar
Elliot Lee committed
1090 1091 1092 1093
{
  CRMatrix geometry;
  CRMatrix tmp1, tmp2;
  CRMatrix deltas;
1094 1095 1096 1097 1098 1099
  gdouble  x, dx, dx2, dx3;
  gdouble  y, dy, dy2, dy3;
  gdouble  d, d2, d3;
  gint     lastx, lasty;
  gint32   newx, newy;
  gint     i;
Elliot Lee's avatar
Elliot Lee committed
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145

  /* construct the geometry matrix from the segment */
  for (i = 0; i < 4; i++)
    {
      geometry[i][2] = 0;
      geometry[i][3] = 0;
    }

  for (i = 0; i < 2; i++)
    {
      geometry[0][i] = cd->points[cd->channel][p1][i];
      geometry[1][i] = cd->points[cd->channel][p2][i];
      geometry[2][i] = cd->points[cd->channel][p3][i];
      geometry[3][i] = cd->points[cd->channel][p4][i];
    }

  /* subdivide the curve 1000 times */
  /* n can be adjusted to give a finer or coarser curve */
  d = 1.0 / 1000;
  d2 = d * d;
  d3 = d * d * d;

  /* construct a temporary matrix for determining the forward differencing deltas */
  tmp2[0][0] = 0;     tmp2[0][1] = 0;     tmp2[0][2] = 0;    tmp2[0][3] = 1;
  tmp2[1][0] = d3;    tmp2[1][1] = d2;    tmp2[1][2] = d;    tmp2[1][3] = 0;
  tmp2[2][0] = 6*d3;  tmp2[2][1] = 2*d2;  tmp2[2][2] = 0;    tmp2[2][3] = 0;
  tmp2[3][0] = 6*d3;  tmp2[3][1] = 0;     tmp2[3][2] = 0;    tmp2[3][3] = 0;

  /* compose the basis and geometry matrices */
  curves_CR_compose (CR_basis, geometry, tmp1);

  /* compose the above results to get the deltas matrix */
  curves_CR_compose (tmp2, tmp1, deltas);

  /* extract the x deltas */
  x = deltas[0][0];
  dx = deltas[1][0];
  dx2 = deltas[2][0];
  dx3 = deltas[3][0];

  /* extract the y deltas */
  y = deltas[0][1];
  dy = deltas[1][1];
  dy2 = deltas[2][1];
  dy3 = deltas[3][1];

1146 1147
  lastx = CLAMP (x, 0, 255);
  lasty = CLAMP (y, 0, 255);
Elliot Lee's avatar