src/widgets/sp-color-slider.cpp

   1 #define __SP_COLOR_SLIDER_C__
   2
   3 /*
   4  * A slider with colored background
   5  *
   6  * Author:
   7  *   Lauris Kaplinski <lauris@kaplinski.com>
   8  *   bulia byak <buliabyak@users.sf.net>
   9  *
  10  * Copyright (C) 2001-2002 Lauris Kaplinski
  11  *
  12  * This code is in public domain
  13  */
  14
  15 #include <gtk/gtkversion.h>
  16 #include <gtk/gtksignal.h>
  17 #include "sp-color-scales.h"
  18
  19 #define SLIDER_WIDTH 96
  20 #define SLIDER_HEIGHT 8
  21 #define ARROW_SIZE 7
  22
  23 enum {
  24         GRABBED,
  25         DRAGGED,
  26         RELEASED,
  27         CHANGED,
  28         LAST_SIGNAL
  29 };
  30
  31 static void sp_color_slider_class_init (SPColorSliderClass *klass);
  32 static void sp_color_slider_init (SPColorSlider *slider);
  33 static void sp_color_slider_destroy (GtkObject *object);
  34
  35 static void sp_color_slider_realize (GtkWidget *widget);
  36 static void sp_color_slider_size_request (GtkWidget *widget, GtkRequisition *requisition);
  37 static void sp_color_slider_size_allocate (GtkWidget *widget, GtkAllocation *allocation);
  38 /*  static void sp_color_slider_draw (GtkWidget *widget, GdkRectangle *area); */
  39 /*  static void sp_color_slider_draw_focus (GtkWidget *widget); */
  40 /*  static void sp_color_slider_draw_default (GtkWidget *widget); */
  41
  42 static gint sp_color_slider_expose (GtkWidget *widget, GdkEventExpose *event);
  43 static gint sp_color_slider_button_press (GtkWidget *widget, GdkEventButton *event);
  44 static gint sp_color_slider_button_release (GtkWidget *widget, GdkEventButton *event);
  45 static gint sp_color_slider_motion_notify (GtkWidget *widget, GdkEventMotion *event);
  46
  47 static void sp_color_slider_adjustment_changed (GtkAdjustment *adjustment, SPColorSlider *slider);
  48 static void sp_color_slider_adjustment_value_changed (GtkAdjustment *adjustment, SPColorSlider *slider);
  49
  50 static void sp_color_slider_paint (SPColorSlider *slider, GdkRectangle *area);
  51 static const guchar *sp_color_slider_render_gradient (gint x0, gint y0, gint width, gint height,
  52                                                       gint c[], gint dc[], guint b0, guint b1, guint mask);
  53 static const guchar *sp_color_slider_render_map (gint x0, gint y0, gint width, gint height,
  54                                                  guchar *map, gint start, gint step, guint b0, guint b1, guint mask);
  55
  56 static GtkWidgetClass *parent_class;
  57 static guint slider_signals[LAST_SIGNAL] = {0};
  58
  59 GtkType
  60 sp_color_slider_get_type (void)
  61 {
  62         static GtkType type = 0;
  63         if (!type) {
  64                 GtkTypeInfo info = {
  65                         "SPColorSlider",
  66                         sizeof (SPColorSlider),
  67                         sizeof (SPColorSliderClass),
  68                         (GtkClassInitFunc) sp_color_slider_class_init,
  69                         (GtkObjectInitFunc) sp_color_slider_init,
  70                         NULL, NULL, NULL
  71                 };
  72                 type = gtk_type_unique (GTK_TYPE_WIDGET, &info);
  73         }
  74         return type;
  75 }
  76
  77 static void
  78 sp_color_slider_class_init (SPColorSliderClass *klass)
  79 {
  80         GtkObjectClass *object_class;
  81         GtkWidgetClass *widget_class;
  82
  83         object_class = (GtkObjectClass *) klass;
  84         widget_class = (GtkWidgetClass *) klass;
  85
  86         parent_class = (GtkWidgetClass*)gtk_type_class (GTK_TYPE_WIDGET);
  87
  88         slider_signals[GRABBED] = gtk_signal_new ("grabbed",
  89                                                   (GtkSignalRunType)(GTK_RUN_FIRST | GTK_RUN_NO_RECURSE),
  90                                                   GTK_CLASS_TYPE(object_class),
  91                                                   GTK_SIGNAL_OFFSET (SPColorSliderClass, grabbed),
  92                                                   gtk_marshal_NONE__NONE,
  93                                                   GTK_TYPE_NONE, 0);
  94         slider_signals[DRAGGED] = gtk_signal_new ("dragged",
  95                                                   (GtkSignalRunType)(GTK_RUN_FIRST | GTK_RUN_NO_RECURSE),
  96                                                   GTK_CLASS_TYPE(object_class),
  97                                                   GTK_SIGNAL_OFFSET (SPColorSliderClass, dragged),
  98                                                   gtk_marshal_NONE__NONE,
  99                                                   GTK_TYPE_NONE, 0);
 100         slider_signals[RELEASED] = gtk_signal_new ("released",
 101                                                   (GtkSignalRunType)(GTK_RUN_FIRST | GTK_RUN_NO_RECURSE),
 102                                                   GTK_CLASS_TYPE(object_class),
 103                                                   GTK_SIGNAL_OFFSET (SPColorSliderClass, released),
 104                                                   gtk_marshal_NONE__NONE,
 105                                                   GTK_TYPE_NONE, 0);
 106         slider_signals[CHANGED] = gtk_signal_new ("changed",
 107                                                   (GtkSignalRunType)(GTK_RUN_FIRST | GTK_RUN_NO_RECURSE),
 108                                                   GTK_CLASS_TYPE(object_class),
 109                                                   GTK_SIGNAL_OFFSET (SPColorSliderClass, changed),
 110                                                   gtk_marshal_NONE__NONE,
 111                                                   GTK_TYPE_NONE, 0);
 112
 113         object_class->destroy = sp_color_slider_destroy;
 114
 115         widget_class->realize = sp_color_slider_realize;
 116         widget_class->size_request = sp_color_slider_size_request;
 117         widget_class->size_allocate = sp_color_slider_size_allocate;
 118 /*      widget_class->draw = sp_color_slider_draw; */
 119 /*      widget_class->draw_focus = sp_color_slider_draw_focus; */
 120 /*      widget_class->draw_default = sp_color_slider_draw_default; */
 121
 122         widget_class->expose_event = sp_color_slider_expose;
 123         widget_class->button_press_event = sp_color_slider_button_press;
 124         widget_class->button_release_event = sp_color_slider_button_release;
 125         widget_class->motion_notify_event = sp_color_slider_motion_notify;
 126 }
 127
 128 static void
 129 sp_color_slider_init (SPColorSlider *slider)
 130 {
 131         /* We are widget with window */
 132         GTK_WIDGET_UNSET_FLAGS (slider, GTK_NO_WINDOW);
 133
 134         slider->dragging = FALSE;
 135
 136         slider->adjustment = NULL;
 137         slider->value = 0.0;
 138
 139         slider->c0[0] = 0x00;
 140         slider->c0[1] = 0x00;
 141         slider->c0[2] = 0x00;
 142         slider->c0[3] = 0xff;
 143
 144         slider->cm[0] = 0xff;
 145         slider->cm[1] = 0x00;
 146         slider->cm[2] = 0x00;
 147         slider->cm[3] = 0xff;
 148
 149         slider->c1[0] = 0xff;
 150         slider->c1[1] = 0xff;
 151         slider->c1[2] = 0xff;
 152         slider->c1[3] = 0xff;
 153
 154         slider->b0 = 0x5f;
 155         slider->b1 = 0xa0;
 156         slider->bmask = 0x08;
 157
 158         slider->map = NULL;
 159 }
 160
 161 static void
 162 sp_color_slider_destroy (GtkObject *object)
 163 {
 164         SPColorSlider *slider;
 165
 166         slider = SP_COLOR_SLIDER (object);
 167
 168         if (slider->adjustment) {
 169                 gtk_signal_disconnect_by_data (GTK_OBJECT (slider->adjustment), slider);
 170                 gtk_object_unref (GTK_OBJECT (slider->adjustment));
 171                 slider->adjustment = NULL;
 172         }
 173
 174         if (((GtkObjectClass *) (parent_class))->destroy)
 175                 (* ((GtkObjectClass *) (parent_class))->destroy) (object);
 176 }
 177
 178 static void
 179 sp_color_slider_realize (GtkWidget *widget)
 180 {
 181         SPColorSlider *slider;
 182         GdkWindowAttr attributes;
 183         gint attributes_mask;
 184
 185         slider = SP_COLOR_SLIDER (widget);
 186
 187         GTK_WIDGET_SET_FLAGS (widget, GTK_REALIZED);
 188
 189         attributes.window_type = GDK_WINDOW_CHILD;
 190         attributes.x = widget->allocation.x;
 191         attributes.y = widget->allocation.y;
 192         attributes.width = widget->allocation.width;
 193         attributes.height = widget->allocation.height;
 194         attributes.wclass = GDK_INPUT_OUTPUT;
 195         attributes.visual = gdk_rgb_get_visual ();
 196         attributes.colormap = gdk_rgb_get_cmap ();
 197         attributes.event_mask = gtk_widget_get_events (widget);
 198         attributes.event_mask |= (GDK_EXPOSURE_MASK |
 199                                   GDK_BUTTON_PRESS_MASK |
 200                                   GDK_BUTTON_RELEASE_MASK |
 201                                   GDK_POINTER_MOTION_MASK |
 202                                   GDK_ENTER_NOTIFY_MASK |
 203                                   GDK_LEAVE_NOTIFY_MASK);
 204         attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;
 205
 206         widget->window = gdk_window_new (gtk_widget_get_parent_window (widget), &attributes, attributes_mask);
 207         gdk_window_set_user_data (widget->window, widget);
 208
 209         widget->style = gtk_style_attach (widget->style, widget->window);
 210 }
 211
 212 static void
 213 sp_color_slider_size_request (GtkWidget *widget, GtkRequisition *requisition)
 214 {
 215         SPColorSlider *slider;
 216
 217         slider = SP_COLOR_SLIDER (widget);
 218
 219         requisition->width = SLIDER_WIDTH + widget->style->xthickness * 2;
 220         requisition->height = SLIDER_HEIGHT + widget->style->ythickness * 2;
 221 }
 222
 223 static void
 224 sp_color_slider_size_allocate (GtkWidget *widget, GtkAllocation *allocation)
 225 {
 226         SPColorSlider *slider;
 227
 228         slider = SP_COLOR_SLIDER (widget);
 229
 230         widget->allocation = *allocation;
 231
 232         if (GTK_WIDGET_REALIZED (widget)) {
 233                 /* Resize GdkWindow */
 234                 gdk_window_move_resize (widget->window, allocation->x, allocation->y, allocation->width, allocation->height);
 235         }
 236 }
 237
 238 static gint
 239 sp_color_slider_expose (GtkWidget *widget, GdkEventExpose *event)
 240 {
 241         SPColorSlider *slider;
 242
 243         slider = SP_COLOR_SLIDER (widget);
 244
 245         if (GTK_WIDGET_DRAWABLE (widget)) {
 246                 gint width, height;
 247                 width = widget->allocation.width;
 248                 height = widget->allocation.height;
 249                 sp_color_slider_paint (slider, &event->area);
 250         }
 251
 252         return FALSE;
 253 }
 254
 255 static gint
 256 sp_color_slider_button_press (GtkWidget *widget, GdkEventButton *event)
 257 {
 258         SPColorSlider *slider;
 259
 260         slider = SP_COLOR_SLIDER (widget);
 261
 262         if (event->button == 1) {
 263                 gint cx, cw;
 264                 cx = widget->style->xthickness;
 265                 cw = widget->allocation.width - 2 * cx;
 266                 gtk_signal_emit (GTK_OBJECT (slider), slider_signals[GRABBED]);
 267                 slider->dragging = TRUE;
 268                 slider->oldvalue = slider->value;
 269                 ColorScales::setScaled( slider->adjustment, CLAMP ((gfloat) (event->x - cx) / cw, 0.0, 1.0) );
 270                 gtk_signal_emit (GTK_OBJECT (slider), slider_signals[DRAGGED]);
 271                 gdk_pointer_grab (widget->window, FALSE,
 272                                   (GdkEventMask)(GDK_POINTER_MOTION_MASK |
 273                                   GDK_BUTTON_RELEASE_MASK),
 274                                   NULL, NULL, event->time);
 275         }
 276
 277         return FALSE;
 278 }
 279
 280 static gint
 281 sp_color_slider_button_release (GtkWidget *widget, GdkEventButton *event)
 282 {
 283         SPColorSlider *slider;
 284
 285         slider = SP_COLOR_SLIDER (widget);
 286
 287         if (event->button == 1) {
 288                 gdk_pointer_ungrab (event->time);
 289                 slider->dragging = FALSE;
 290                 gtk_signal_emit (GTK_OBJECT (slider), slider_signals[RELEASED]);
 291                 if (slider->value != slider->oldvalue) gtk_signal_emit (GTK_OBJECT (slider), slider_signals[CHANGED]);
 292         }
 293
 294         return FALSE;
 295 }
 296
 297 static gint
 298 sp_color_slider_motion_notify (GtkWidget *widget, GdkEventMotion *event)
 299 {
 300         SPColorSlider *slider;
 301
 302         slider = SP_COLOR_SLIDER (widget);
 303
 304         if (slider->dragging) {
 305                 gint cx, cw;
 306                 cx = widget->style->xthickness;
 307                 cw = widget->allocation.width - 2 * cx;
 308                 ColorScales::setScaled( slider->adjustment, CLAMP ((gfloat) (event->x - cx) / cw, 0.0, 1.0) );
 309                 gtk_signal_emit (GTK_OBJECT (slider), slider_signals[DRAGGED]);
 310         }
 311
 312         return FALSE;
 313 }
 314
 315 GtkWidget *
 316 sp_color_slider_new (GtkAdjustment *adjustment)
 317 {
 318         SPColorSlider *slider;
 319
 320         slider = (SPColorSlider*)gtk_type_new (SP_TYPE_COLOR_SLIDER);
 321
 322         sp_color_slider_set_adjustment (slider, adjustment);
 323
 324         return GTK_WIDGET (slider);
 325 }
 326
 327 void
 328 sp_color_slider_set_adjustment (SPColorSlider *slider, GtkAdjustment *adjustment)
 329 {
 330         g_return_if_fail (slider != NULL);
 331         g_return_if_fail (SP_IS_COLOR_SLIDER (slider));
 332
 333         if (!adjustment) {
 334                 adjustment = (GtkAdjustment *) gtk_adjustment_new (0.0, 0.0, 1.0, 0.01, 0.0, 0.0);
 335         }
 336 #if GTK_CHECK_VERSION (2,14,0)
 337     else {
 338         gtk_adjustment_set_page_increment(adjustment, 0.0);
 339         gtk_adjustment_set_page_size(adjustment, 0.0);
 340     }
 341 #endif
 342
 343         if (slider->adjustment != adjustment) {
 344                 if (slider->adjustment) {
 345                         gtk_signal_disconnect_by_data (GTK_OBJECT (slider->adjustment), slider);
 346                         gtk_object_unref (GTK_OBJECT (slider->adjustment));
 347                 }
 348
 349                 slider->adjustment = adjustment;
 350                 gtk_object_ref (GTK_OBJECT (adjustment));
 351                 gtk_object_sink (GTK_OBJECT (adjustment));
 352
 353                 gtk_signal_connect (GTK_OBJECT (adjustment), "changed",
 354                                     GTK_SIGNAL_FUNC (sp_color_slider_adjustment_changed), slider);
 355                 gtk_signal_connect (GTK_OBJECT (adjustment), "value_changed",
 356                                     GTK_SIGNAL_FUNC (sp_color_slider_adjustment_value_changed), slider);
 357
 358                 slider->value = ColorScales::getScaled( adjustment );
 359
 360                 sp_color_slider_adjustment_changed (adjustment, slider);
 361         }
 362 }
 363
 364 void
 365 sp_color_slider_set_colors (SPColorSlider *slider, guint32 start, guint32 mid, guint32 end)
 366 {
 367         g_return_if_fail (slider != NULL);
 368         g_return_if_fail (SP_IS_COLOR_SLIDER (slider));
 369
 370         // Remove any map, if set
 371         slider->map = 0;
 372
 373         slider->c0[0] = start >> 24;
 374         slider->c0[1] = (start >> 16) & 0xff;
 375         slider->c0[2] = (start >> 8) & 0xff;
 376         slider->c0[3] = start & 0xff;
 377
 378         slider->cm[0] = mid >> 24;
 379         slider->cm[1] = (mid >> 16) & 0xff;
 380         slider->cm[2] = (mid >> 8) & 0xff;
 381         slider->cm[3] = mid & 0xff;
 382
 383         slider->c1[0] = end >> 24;
 384         slider->c1[1] = (end >> 16) & 0xff;
 385         slider->c1[2] = (end >> 8) & 0xff;
 386         slider->c1[3] = end & 0xff;
 387
 388         gtk_widget_queue_draw (GTK_WIDGET (slider));
 389 }
 390
 391 void
 392 sp_color_slider_set_map (SPColorSlider *slider, const guchar *map)
 393 {
 394         g_return_if_fail (slider != NULL);
 395         g_return_if_fail (SP_IS_COLOR_SLIDER (slider));
 396
 397         slider->map = (guchar *) map;
 398
 399         gtk_widget_queue_draw (GTK_WIDGET (slider));
 400 }
 401
 402 void
 403 sp_color_slider_set_background (SPColorSlider *slider, guint dark, guint light, guint size)
 404 {
 405         g_return_if_fail (slider != NULL);
 406         g_return_if_fail (SP_IS_COLOR_SLIDER (slider));
 407
 408         slider->b0 = dark;
 409         slider->b1 = light;
 410         slider->bmask = size;
 411
 412         gtk_widget_queue_draw (GTK_WIDGET (slider));
 413 }
 414
 415 static void
 416 sp_color_slider_adjustment_changed (GtkAdjustment */*adjustment*/, SPColorSlider *slider)
 417 {
 418         gtk_widget_queue_draw (GTK_WIDGET (slider));
 419 }
 420
 421 static void
 422 sp_color_slider_adjustment_value_changed (GtkAdjustment *adjustment, SPColorSlider *slider)
 423 {
 424         GtkWidget *widget;
 425
 426         widget = GTK_WIDGET (slider);
 427
 428         if (slider->value != ColorScales::getScaled( adjustment )) {
 429                 gint cx, cy, cw, ch;
 430                 cx = widget->style->xthickness;
 431                 cy = widget->style->ythickness;
 432                 cw = widget->allocation.width - 2 * cx;
 433                 ch = widget->allocation.height - 2 * cy;
 434                 if ((gint) (ColorScales::getScaled( adjustment ) * cw) != (gint) (slider->value * cw)) {
 435                         gint ax, ay;
 436                         gfloat value;
 437                         value = slider->value;
 438                         slider->value = ColorScales::getScaled( adjustment );
 439                         ax = (int)(cx + value * cw - ARROW_SIZE / 2 - 2);
 440                         ay = cy;
 441                         gtk_widget_queue_draw_area (widget, ax, ay, ARROW_SIZE + 4, ch);
 442                         ax = (int)(cx + slider->value * cw - ARROW_SIZE / 2 - 2);
 443                         ay = cy;
 444                         gtk_widget_queue_draw_area (widget, ax, ay, ARROW_SIZE + 4, ch);
 445                 } else {
 446                         slider->value = ColorScales::getScaled( adjustment );
 447                 }
 448         }
 449 }
 450
 451 static void
 452 sp_color_slider_paint (SPColorSlider *slider, GdkRectangle *area)
 453 {
 454         GtkWidget *widget;
 455         GdkRectangle warea, carea, aarea;
 456         GdkRectangle wpaint, cpaint, apaint;
 457         const guchar *b;
 458         gint w, x, y1, y2;
 459
 460         widget = GTK_WIDGET (slider);
 461
 462         /* Widget area */
 463         warea.x = 0;
 464         warea.y = 0;
 465         warea.width = widget->allocation.width;
 466         warea.height = widget->allocation.height;
 467
 468         /* Color gradient area */
 469         carea.x = widget->style->xthickness;
 470         carea.y = widget->style->ythickness;
 471         carea.width = widget->allocation.width - 2 * carea.x;
 472         carea.height = widget->allocation.height - 2 * carea.y;
 473
 474         /* Arrow area */
 475         aarea.x = (int)(slider->value * (carea.width - 1) - ARROW_SIZE / 2 + carea.x);
 476         aarea.width = ARROW_SIZE;
 477         aarea.y = carea.y;
 478         aarea.height = carea.height;
 479
 480         /* Actual paintable area */
 481         if (!gdk_rectangle_intersect (area, &warea, &wpaint)) return;
 482
 483         b = NULL;
 484
 485         /* Paintable part of color gradient area */
 486         if (gdk_rectangle_intersect (area, &carea, &cpaint)) {
 487                 if (slider->map) {
 488                         gint s, d;
 489                         /* Render map pixelstore */
 490                         d = (1024 << 16) / carea.width;
 491                         s = (cpaint.x - carea.x) * d;
 492                         b = sp_color_slider_render_map (cpaint.x - carea.x, cpaint.y - carea.y, cpaint.width, cpaint.height,
 493                                                                                                                                                         slider->map, s, d,
 494                                                                                                                                                         slider->b0, slider->b1, slider->bmask);
 495                         if (b != NULL) {
 496                                 gdk_draw_rgb_image (widget->window, widget->style->black_gc,
 497                                                                                                                 cpaint.x, cpaint.y,
 498                                                                                                                 cpaint.width, cpaint.height,
 499                                                                                                                 GDK_RGB_DITHER_MAX,
 500                                                                                                                 (guchar *) b, cpaint.width * 3);
 501                         }
 502
 503                 } else {
 504                         gint c[4], dc[4];
 505                         gint i;
 506                         /* Render gradient */
 507
 508                         // part 1: from c0 to cm
 509                         if ((cpaint.x - carea.x) <= carea.width/2) {
 510                                 for (i = 0; i < 4; i++) {
 511                                         c[i] = slider->c0[i] << 16;
 512                                         dc[i] = ((slider->cm[i] << 16) - c[i]) / (carea.width/2);
 513                                         c[i] += (cpaint.x - carea.x) * dc[i];
 514                                 }
 515                                 guint wi = MIN(cpaint.x - carea.x + cpaint.width, carea.width/2) - (cpaint.x - carea.x);
 516                                 b = sp_color_slider_render_gradient (cpaint.x - carea.x, cpaint.y - carea.y, wi, cpaint.height,
 517                                                                                                          c, dc,
 518                                                                                                          slider->b0, slider->b1, slider->bmask);
 519
 520                                 /* Draw pixelstore */
 521                                 if (b != NULL) {
 522                                         gdk_draw_rgb_image (widget->window, widget->style->black_gc,
 523                                                                                                                         cpaint.x, cpaint.y,
 524                                                                                                                         wi, cpaint.height,
 525                                                                                                                         GDK_RGB_DITHER_MAX,
 526                                                                                                                         (guchar *) b, wi * 3);
 527                                 }
 528                         }
 529
 530                         // part 2: from cm to c1
 531                         if ((cpaint.x - carea.x + cpaint.width) > carea.width/2) {
 532                                 for (i = 0; i < 4; i++) {
 533                                         c[i] = slider->cm[i] << 16;
 534                                         dc[i] = ((slider->c1[i] << 16) - c[i]) / (carea.width/2);
 535                                         if ((cpaint.x - carea.x) > carea.width/2)
 536                                                 c[i] += (cpaint.x - carea.x - carea.width/2) * dc[i];
 537                                 }
 538                                 guint wi = cpaint.width - MAX(0, (carea.width/2 - (cpaint.x - carea.x)));
 539                                 b = sp_color_slider_render_gradient (MAX(cpaint.x - carea.x, carea.width/2), cpaint.y - carea.y, wi, cpaint.height,
 540                                                                                                  c, dc,
 541                                                                                                  slider->b0, slider->b1, slider->bmask);
 542
 543                                 /* Draw pixelstore */
 544                                 if (b != NULL) {
 545                                         gdk_draw_rgb_image (widget->window, widget->style->black_gc,
 546                                                                                                                         MAX(cpaint.x, carea.width/2 + carea.x), cpaint.y,
 547                                                                                                                         wi, cpaint.height,
 548                                                                                                                         GDK_RGB_DITHER_MAX,
 549                                                                                                                         (guchar *) b, wi * 3);
 550                                 }
 551                         }
 552                 }
 553         }
 554
 555         /* Draw shadow */
 556         gtk_paint_shadow (widget->style, widget->window,
 557                           (GtkStateType)widget->state, GTK_SHADOW_IN,
 558                           area, widget, "colorslider",
 559                           0, 0,
 560                           warea.width, warea.height);
 561
 562
 563         if (gdk_rectangle_intersect (area, &aarea, &apaint)) {
 564                 /* Draw arrow */
 565                 gdk_rectangle_intersect (&carea, &apaint, &apaint);
 566                 gdk_gc_set_clip_rectangle (widget->style->white_gc, &apaint);
 567                 gdk_gc_set_clip_rectangle (widget->style->black_gc, &apaint);
 568
 569                 x = aarea.x;
 570                 y1 = carea.y;
 571                 y2 = aarea.y + aarea.height - 1;
 572                 w = aarea.width;
 573                 while ( w > 0 )
 574                 {
 575                         gdk_draw_line (widget->window, widget->style->white_gc, x, y1, x + w - 1, y1 );
 576                         gdk_draw_line (widget->window, widget->style->white_gc, x, y2, x + w - 1, y2 );
 577                         w -=2;
 578                         x++;
 579                         if ( w > 0 )
 580                         {
 581                                 gdk_draw_line (widget->window, widget->style->black_gc, x, y1, x + w - 1, y1 );
 582                                 gdk_draw_line (widget->window, widget->style->black_gc, x, y2, x + w - 1, y2 );
 583                         }
 584                         y1++;
 585                         y2--;
 586                 }
 587
 588                 gdk_gc_set_clip_rectangle (widget->style->white_gc, NULL);
 589                 gdk_gc_set_clip_rectangle (widget->style->black_gc, NULL);
 590         }
 591 }
 592
 593 /* Colors are << 16 */
 594
 595 static const guchar *
 596 sp_color_slider_render_gradient (gint x0, gint y0, gint width, gint height,
 597                                  gint c[], gint dc[], guint b0, guint b1, guint mask)
 598 {
 599         static guchar *buf = NULL;
 600         static gint bs = 0;
 601         guchar *dp;
 602         gint x, y;
 603         guint r, g, b, a;
 604
 605         if (buf && (bs < width * height)) {
 606                 g_free (buf);
 607                 buf = NULL;
 608         }
 609         if (!buf) {
 610                 buf = g_new (guchar, width * height * 3);
 611                 bs = width * height;
 612         }
 613
 614         dp = buf;
 615         r = c[0];
 616         g = c[1];
 617         b = c[2];
 618         a = c[3];
 619         for (x = x0; x < x0 + width; x++) {
 620                 gint cr, cg, cb, ca;
 621                 guchar *d;
 622                 cr = r >> 16;
 623                 cg = g >> 16;
 624                 cb = b >> 16;
 625                 ca = a >> 16;
 626                 d = dp;
 627                 for (y = y0; y < y0 + height; y++) {
 628                         guint bg, fc;
 629                         /* Background value */
 630                         bg = ((x & mask) ^ (y & mask)) ? b0 : b1;
 631                         fc = (cr - bg) * ca;
 632                         d[0] = bg + ((fc + (fc >> 8) + 0x80) >> 8);
 633                         fc = (cg - bg) * ca;
 634                         d[1] = bg + ((fc + (fc >> 8) + 0x80) >> 8);
 635                         fc = (cb - bg) * ca;
 636                         d[2] = bg + ((fc + (fc >> 8) + 0x80) >> 8);
 637                         d += 3 * width;
 638                 }
 639                 r += dc[0];
 640                 g += dc[1];
 641                 b += dc[2];
 642                 a += dc[3];
 643                 dp += 3;
 644         }
 645
 646         return buf;
 647 }
 648
 649 /* Positions are << 16 */
 650
 651 static const guchar *
 652 sp_color_slider_render_map (gint x0, gint y0, gint width, gint height,
 653                             guchar *map, gint start, gint step, guint b0, guint b1, guint mask)
 654 {
 655         static guchar *buf = NULL;
 656         static gint bs = 0;
 657         guchar *dp, *sp;
 658         gint x, y;
 659
 660         if (buf && (bs < width * height)) {
 661                 g_free (buf);
 662                 buf = NULL;
 663         }
 664         if (!buf) {
 665                 buf = g_new (guchar, width * height * 3);
 666                 bs = width * height;
 667         }
 668
 669         dp = buf;
 670         for (x = x0; x < x0 + width; x++) {
 671                 gint cr, cg, cb, ca;
 672                 guchar *d;
 673                 sp = map + 4 * (start >> 16);
 674                 cr = *sp++;
 675                 cg = *sp++;
 676                 cb = *sp++;
 677                 ca = *sp++;
 678                 d = dp;
 679                 for (y = y0; y < y0 + height; y++) {
 680                         guint bg, fc;
 681                         /* Background value */
 682                         bg = ((x & mask) ^ (y & mask)) ? b0 : b1;
 683                         fc = (cr - bg) * ca;
 684                         d[0] = bg + ((fc + (fc >> 8) + 0x80) >> 8);
 685                         fc = (cg - bg) * ca;
 686                         d[1] = bg + ((fc + (fc >> 8) + 0x80) >> 8);
 687                         fc = (cb - bg) * ca;
 688                         d[2] = bg + ((fc + (fc >> 8) + 0x80) >> 8);
 689                         d += 3 * width;
 690                 }
 691                 dp += 3;
 692                 start += step;
 693         }
 694
 695         return buf;
 696 }
 697