src/custom_ctl.cpp

   1 /* Calf DSP Library
   2  * Custom controls (line graph, knob).
   3  * Copyright (C) 2007 Krzysztof Foltman
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this program; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  */
  20 #include "config.h"
  21 #include <calf/custom_ctl.h>
  22 #include <gdk/gdkkeysyms.h>
  23 #include <cairo/cairo.h>
  24 #include <math.h>
  25 #include <gdk/gdk.h>
  26
  27 /*
  28 I don't really know how to do it, or if it can be done this way.
  29 struct calf_ui_type_module
  30 {
  31     GTypeModule *module;
  32
  33     calf_ui_type_module()
  34     {
  35         module = g_type_module_new();
  36         g_type_module_set_name(module, "calf_custom_ctl");
  37         g_type_module_use(module);
  38     }
  39     ~calf_ui_type_module()
  40     {
  41         g_type_module_unuse(module);
  42     }
  43 };
  44
  45 static calf_ui_type_module type_module;
  46 */
  47
  48 static void
  49 calf_line_graph_copy_cache_to_window( CalfLineGraph *lg, cairo_t *c )
  50 {
  51     cairo_save( c );
  52     cairo_set_source_surface( c, lg->cache_surface, 0,0 );
  53     cairo_paint( c );
  54     cairo_restore( c );
  55 }
  56
  57 static void
  58 calf_line_graph_copy_window_to_cache( CalfLineGraph *lg, cairo_t *c )
  59 {
  60     cairo_t *cache_cr = cairo_create( lg->cache_surface );
  61     cairo_surface_t *window_surface = cairo_get_target( c );
  62     cairo_set_source_surface( cache_cr, window_surface, 0,0 );
  63     cairo_paint( cache_cr );
  64     cairo_destroy( cache_cr );
  65 }
  66
  67 static void
  68 calf_line_graph_draw_grid( cairo_t *c, std::string &legend, bool vertical, float pos, int phase, int sx, int sy )
  69 {
  70     int ox=1, oy=1;
  71     cairo_text_extents_t tx;
  72     if (!legend.empty())
  73         cairo_text_extents(c, legend.c_str(), &tx);
  74     if (vertical)
  75     {
  76         float x = floor(ox + pos * sx) + 0.5;
  77         if (phase == 1)
  78         {
  79             cairo_move_to(c, x, oy);
  80             cairo_line_to(c, x, oy + sy);
  81             cairo_stroke(c);
  82         }
  83         if (phase == 2 && !legend.empty()) {
  84
  85             cairo_set_source_rgba(c, 1.0, 1.0, 1.0, 0.75);
  86             cairo_move_to(c, x - (tx.x_bearing + tx.width / 2.0), oy + sy - 2);
  87             cairo_show_text(c, legend.c_str());
  88         }
  89     }
  90     else
  91     {
  92         float y = floor(oy + sy / 2 - (sy / 2 - 1) * pos) + 0.5;
  93         if (phase == 1)
  94         {
  95             cairo_move_to(c, ox, y);
  96             cairo_line_to(c, ox + sx, y);
  97             cairo_stroke(c);
  98         }
  99         if (phase == 2 && !legend.empty()) {
 100             cairo_set_source_rgba(c, 1.0, 1.0, 1.0, 0.75);
 101             cairo_move_to(c, ox + sx - 2 - tx.width, y + tx.height/2 - 1);
 102             cairo_show_text(c, legend.c_str());
 103         }
 104     }
 105 }
 106
 107 static void
 108 calf_line_graph_draw_graph( cairo_t *c, float *data, int sx, int sy )
 109 {
 110     int ox=1, oy=1;
 111
 112     for (int i = 0; i < 2 * sx; i++)
 113     {
 114         int y = (int)(oy + sy / 2 - (sy / 2 - 1) * data[i]);
 115         //if (y < oy) y = oy;
 116         //if (y >= oy + sy) y = oy + sy - 1;
 117         if (i)
 118             cairo_line_to(c, ox + i * 0.5, y);
 119         else
 120             cairo_move_to(c, ox, y);
 121     }
 122     cairo_stroke(c);
 123 }
 124
 125 static gboolean
 126 calf_line_graph_expose (GtkWidget *widget, GdkEventExpose *event)
 127 {
 128     g_assert(CALF_IS_LINE_GRAPH(widget));
 129
 130     CalfLineGraph *lg = CALF_LINE_GRAPH(widget);
 131     //int ox = widget->allocation.x + 1, oy = widget->allocation.y + 1;
 132     int ox = 1, oy = 1;
 133     int sx = widget->allocation.width - 2, sy = widget->allocation.height - 2;
 134
 135     cairo_t *c = gdk_cairo_create(GDK_DRAWABLE(widget->window));
 136
 137     GdkColor sc = { 0, 0, 0, 0 };
 138
 139     bool cache_dirty = 0;
 140
 141
 142
 143     if( lg->cache_surface == NULL ) {
 144         // looks like its either first call or the widget has been resized.
 145         // create the cache_surface.
 146         cairo_surface_t *window_surface = cairo_get_target( c );
 147         lg->cache_surface = cairo_surface_create_similar( window_surface,
 148                                                           CAIRO_CONTENT_COLOR,
 149                                                           widget->allocation.width,
 150                                                           widget->allocation.height );
 151         //cairo_set_source_surface( cache_cr, window_surface, 0,0 );
 152         //cairo_paint( cache_cr );
 153
 154         cache_dirty = 1;
 155     }
 156
 157     gdk_cairo_set_source_color(c, &sc);
 158     cairo_rectangle(c, ox, oy, sx, sy);
 159     cairo_clip_preserve(c);
 160     cairo_fill(c);
 161     cairo_impl cimpl;
 162     cimpl.context = c;
 163     cairo_select_font_face(c, "Bitstream Vera Sans", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_NORMAL);
 164     cairo_set_font_size(c, 9);
 165
 166     if (lg->source) {
 167
 168         float pos = 0;
 169         bool vertical = false;
 170         std::string legend;
 171         float *data = new float[2 * sx];
 172         GdkColor sc2 = { 0, 0, 65535, 0 };
 173         float x, y;
 174         int size = 0;
 175         GdkColor sc3 = { 0, 32767, 65535, 0 };
 176
 177         int graph_n, grid_n, dot_n, grid_n_save;
 178
 179         int cache_graph_index, cache_dot_index, cache_grid_index;
 180         int gen_index = lg->source->get_changed_offsets( lg->last_generation, cache_graph_index, cache_dot_index, cache_grid_index );
 181
 182         if( cache_dirty || (gen_index != lg->last_generation) ) {
 183             lg->source->get_changed_offsets( gen_index, cache_graph_index, cache_dot_index, cache_grid_index );
 184             lg->last_generation = gen_index;
 185
 186             cairo_set_line_width(c, 1);
 187             for(int phase = 1; phase <= 2; phase++)
 188             {
 189                 for(grid_n = 0; legend = std::string(), cairo_set_source_rgba(c, 1, 1, 1, 0.5), (grid_n<cache_grid_index) &&  lg->source->get_gridline(lg->source_id, grid_n, pos, vertical, legend, &cimpl); grid_n++)
 190                 {
 191                     calf_line_graph_draw_grid( c, legend, vertical, pos, phase, sx, sy );
 192                 }
 193             }
 194             grid_n_save = grid_n;
 195
 196             gdk_cairo_set_source_color(c, &sc2);
 197             cairo_set_line_join(c, CAIRO_LINE_JOIN_MITER);
 198             cairo_set_line_width(c, 1);
 199             for(graph_n = 0; (graph_n<cache_graph_index) && lg->source->get_graph(lg->source_id, graph_n, data, 2 * sx, &cimpl); graph_n++)
 200             {
 201                 calf_line_graph_draw_graph( c, data, sx, sy );
 202             }
 203             gdk_cairo_set_source_color(c, &sc3);
 204             for(dot_n = 0; (dot_n<cache_dot_index) && lg->source->get_dot(lg->source_id, dot_n, x, y, size = 3, &cimpl); dot_n++)
 205             {
 206                 int yv = (int)(oy + sy / 2 - (sy / 2 - 1) * y);
 207                 cairo_arc(c, ox + x * sx, yv, size, 0, 2 * M_PI);
 208                 cairo_fill(c);
 209             }
 210
 211             // copy window to cache.
 212             calf_line_graph_copy_window_to_cache( lg, c );
 213         } else {
 214             grid_n_save = cache_grid_index;
 215             graph_n = cache_graph_index;
 216             dot_n = cache_dot_index;
 217             calf_line_graph_copy_cache_to_window( lg, c );
 218         }
 219
 220
 221         cairo_set_line_width(c, 1);
 222         for(int phase = 1; phase <= 2; phase++)
 223         {
 224             for(int gn=grid_n_save; legend = std::string(), cairo_set_source_rgba(c, 1, 1, 1, 0.5), lg->source->get_gridline(lg->source_id, gn, pos, vertical, legend, &cimpl); gn++)
 225             {
 226                 calf_line_graph_draw_grid( c, legend, vertical, pos, phase, sx, sy );
 227             }
 228         }
 229
 230         gdk_cairo_set_source_color(c, &sc2);
 231         cairo_set_line_join(c, CAIRO_LINE_JOIN_MITER);
 232         cairo_set_line_width(c, 1);
 233         for(int gn = graph_n; lg->source->get_graph(lg->source_id, gn, data, 2 * sx, &cimpl); gn++)
 234         {
 235             calf_line_graph_draw_graph( c, data, sx, sy );
 236         }
 237         gdk_cairo_set_source_color(c, &sc3);
 238         for(int gn = dot_n; lg->source->get_dot(lg->source_id, gn, x, y, size = 3, &cimpl); gn++)
 239         {
 240             int yv = (int)(oy + sy / 2 - (sy / 2 - 1) * y);
 241             cairo_arc(c, ox + x * sx, yv, size, 0, 2 * M_PI);
 242             cairo_fill(c);
 243         }
 244         delete []data;
 245     }
 246
 247     cairo_destroy(c);
 248
 249     gtk_paint_shadow(widget->style, widget->window, GTK_STATE_NORMAL, GTK_SHADOW_IN, NULL, widget, NULL, ox - 1, oy - 1, sx + 2, sy + 2);
 250     // printf("exposed %p %d+%d\n", widget->window, widget->allocation.x, widget->allocation.y);
 251
 252     return TRUE;
 253 }
 254
 255 void calf_line_graph_set_square(CalfLineGraph *graph, bool is_square)
 256 {
 257     g_assert(CALF_IS_LINE_GRAPH(graph));
 258     graph->is_square = is_square;
 259 }
 260
 261 static void
 262 calf_line_graph_size_request (GtkWidget *widget,
 263                            GtkRequisition *requisition)
 264 {
 265     g_assert(CALF_IS_LINE_GRAPH(widget));
 266
 267     // CalfLineGraph *lg = CALF_LINE_GRAPH(widget);
 268 }
 269
 270 static void
 271 calf_line_graph_size_allocate (GtkWidget *widget,
 272                            GtkAllocation *allocation)
 273 {
 274     g_assert(CALF_IS_LINE_GRAPH(widget));
 275     CalfLineGraph *lg = CALF_LINE_GRAPH(widget);
 276
 277     GtkWidgetClass *parent_class = (GtkWidgetClass *) g_type_class_peek_parent( CALF_LINE_GRAPH_GET_CLASS( lg ) );
 278
 279     if( lg->cache_surface )
 280         cairo_surface_destroy( lg->cache_surface );
 281     lg->cache_surface = NULL;
 282
 283     widget->allocation = *allocation;
 284     GtkAllocation &a = widget->allocation;
 285     if (lg->is_square)
 286     {
 287         if (a.width > a.height)
 288         {
 289             a.x += (a.width - a.height) / 2;
 290             a.width = a.height;
 291         }
 292         if (a.width < a.height)
 293         {
 294             a.y += (a.height - a.width) / 2;
 295             a.height = a.width;
 296         }
 297     }
 298     parent_class->size_allocate( widget, &a );
 299 }
 300
 301 static void
 302 calf_line_graph_class_init (CalfLineGraphClass *klass)
 303 {
 304     // GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 305     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 306     widget_class->expose_event = calf_line_graph_expose;
 307     widget_class->size_request = calf_line_graph_size_request;
 308     widget_class->size_allocate = calf_line_graph_size_allocate;
 309 }
 310
 311 static void
 312 calf_line_graph_init (CalfLineGraph *self)
 313 {
 314     GtkWidget *widget = GTK_WIDGET(self);
 315     widget->requisition.width = 40;
 316     widget->requisition.height = 40;
 317     self->cache_surface = NULL;
 318     self->last_generation = 0;
 319 }
 320
 321 GtkWidget *
 322 calf_line_graph_new()
 323 {
 324     return GTK_WIDGET( g_object_new (CALF_TYPE_LINE_GRAPH, NULL ));
 325 }
 326
 327 GType
 328 calf_line_graph_get_type (void)
 329 {
 330     static GType type = 0;
 331     if (!type) {
 332         static const GTypeInfo type_info = {
 333             sizeof(CalfLineGraphClass),
 334             NULL, /* base_init */
 335             NULL, /* base_finalize */
 336             (GClassInitFunc)calf_line_graph_class_init,
 337             NULL, /* class_finalize */
 338             NULL, /* class_data */
 339             sizeof(CalfLineGraph),
 340             0,    /* n_preallocs */
 341             (GInstanceInitFunc)calf_line_graph_init
 342         };
 343
 344         GTypeInfo *type_info_copy = new GTypeInfo(type_info);
 345
 346         for (int i = 0; ; i++) {
 347             char *name = g_strdup_printf("CalfLineGraph%u%d", ((unsigned int)(intptr_t)calf_line_graph_class_init) >> 16, i);
 348             if (g_type_from_name(name)) {
 349                 free(name);
 350                 continue;
 351             }
 352             type = g_type_register_static( GTK_TYPE_DRAWING_AREA,
 353                                            name,
 354                                            type_info_copy,
 355                                            (GTypeFlags)0);
 356             free(name);
 357             break;
 358         }
 359     }
 360     return type;
 361 }
 362
 363 ///////////////////////////////////////// vu meter ///////////////////////////////////////////////
 364
 365 static gboolean
 366 calf_vumeter_expose (GtkWidget *widget, GdkEventExpose *event)
 367 {
 368     g_assert(CALF_IS_VUMETER(widget));
 369
 370
 371     CalfVUMeter *vu = CALF_VUMETER(widget);
 372     //int ox = widget->allocation.x + 1, oy = widget->allocation.y + 1;
 373     int ox = 1, oy = 1;
 374     int sx = widget->allocation.width - 2, sy = widget->allocation.height - 2;
 375
 376     cairo_t *c = gdk_cairo_create(GDK_DRAWABLE(widget->window));
 377
 378     if( vu->cache_surface == NULL ) {
 379         // looks like its either first call or the widget has been resized.
 380         // create the cache_surface.
 381         cairo_surface_t *window_surface = cairo_get_target( c );
 382         vu->cache_surface = cairo_surface_create_similar( window_surface,
 383                                                           CAIRO_CONTENT_COLOR,
 384                                                           widget->allocation.width,
 385                                                           widget->allocation.height );
 386
 387         // And render the meterstuff again.
 388
 389         cairo_t *cache_cr = cairo_create( vu->cache_surface );
 390         GdkColor sc = { 0, 0, 0, 0 };
 391         gdk_cairo_set_source_color(cache_cr, &sc);
 392         cairo_rectangle(cache_cr, ox, oy, sx, sy);
 393         cairo_fill(cache_cr);
 394         cairo_set_line_width(cache_cr, 1);
 395
 396         for (int x = ox; x <= ox + sx; x += 3)
 397         {
 398             float ts = (x - ox) * 1.0 / sx;
 399             float r = 0.f, g = 0.f, b = 0.f;
 400             switch(vu->mode)
 401             {
 402                 case VU_STANDARD:
 403                 default:
 404                     if (ts < 0.75)
 405                         r = ts / 0.75, g = 1, b = 0;
 406                     else
 407                         r = 1, g = 1 - (ts - 0.75) / 0.25, b = 0;
 408                     //                if (vu->value < ts || vu->value <= 0)
 409                     //                    r *= 0.5, g *= 0.5, b *= 0.5;
 410                     break;
 411                 case VU_MONOCHROME_REVERSE:
 412                     r = 1, g = 1, b = 0;
 413                     //                if (!(vu->value < ts) || vu->value >= 1.0)
 414                     //                    r *= 0.5, g *= 0.5, b *= 0.5;
 415                     break;
 416                 case VU_MONOCHROME:
 417                     r = 1, g = 1, b = 0;
 418                     //                if (vu->value < ts || vu->value <= 0)
 419                     //                    r *= 0.5, g *= 0.5, b *= 0.5;
 420                     break;
 421             }
 422             GdkColor sc2 = { 0, (guint16)(65535 * r), (guint16)(65535 * g), (guint16)(65535 * b) };
 423             gdk_cairo_set_source_color(cache_cr, &sc2);
 424             cairo_move_to(cache_cr, x, oy);
 425             cairo_line_to(cache_cr, x, oy + sy + 1);
 426             cairo_move_to(cache_cr, x, oy + sy);
 427             cairo_line_to(cache_cr, x, oy );
 428             cairo_stroke(cache_cr);
 429         }
 430         cairo_destroy( cache_cr );
 431     }
 432
 433     cairo_set_source_surface( c, vu->cache_surface, 0,0 );
 434     cairo_paint( c );
 435     cairo_set_source_rgba( c, 0,0,0, 0.5 );
 436
 437     if( vu->mode == VU_MONOCHROME_REVERSE )
 438         cairo_rectangle( c, ox,oy, vu->value * (sx-ox) + 1, sy-oy+1 );
 439     else
 440         cairo_rectangle( c, ox + vu->value * (sx-ox), oy, sx-ox+1, sy-oy+1 );
 441
 442     cairo_fill( c );
 443
 444
 445
 446     cairo_destroy(c);
 447
 448     gtk_paint_shadow(widget->style, widget->window, GTK_STATE_NORMAL, GTK_SHADOW_IN, NULL, widget, NULL, ox - 1, oy - 1, sx + 2, sy + 2);
 449     //printf("exposed %p %d+%d\n", widget->window, widget->allocation.x, widget->allocation.y);
 450
 451     return TRUE;
 452 }
 453
 454 static void
 455 calf_vumeter_size_request (GtkWidget *widget,
 456                            GtkRequisition *requisition)
 457 {
 458     g_assert(CALF_IS_VUMETER(widget));
 459
 460     requisition->width = 50;
 461     requisition->height = 14;
 462 }
 463
 464 static void
 465 calf_vumeter_size_allocate (GtkWidget *widget,
 466                            GtkAllocation *allocation)
 467 {
 468     g_assert(CALF_IS_VUMETER(widget));
 469     CalfVUMeter *vu = CALF_VUMETER(widget);
 470
 471     GtkWidgetClass *parent_class = (GtkWidgetClass *) g_type_class_peek_parent( CALF_VUMETER_GET_CLASS( vu ) );
 472
 473     parent_class->size_allocate( widget, allocation );
 474
 475     if( vu->cache_surface )
 476         cairo_surface_destroy( vu->cache_surface );
 477     vu->cache_surface = NULL;
 478 }
 479
 480 static void
 481 calf_vumeter_class_init (CalfVUMeterClass *klass)
 482 {
 483     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 484     widget_class->expose_event = calf_vumeter_expose;
 485     widget_class->size_request = calf_vumeter_size_request;
 486     widget_class->size_allocate = calf_vumeter_size_allocate;
 487 }
 488
 489 static void
 490 calf_vumeter_init (CalfVUMeter *self)
 491 {
 492     GtkWidget *widget = GTK_WIDGET(self);
 493     //GTK_WIDGET_SET_FLAGS (widget, GTK_NO_WINDOW);
 494     widget->requisition.width = 50;
 495     widget->requisition.height = 15;
 496     self->value = 0.5;
 497     self->cache_surface = NULL;
 498 }
 499
 500 GtkWidget *
 501 calf_vumeter_new()
 502 {
 503     return GTK_WIDGET( g_object_new (CALF_TYPE_VUMETER, NULL ));
 504 }
 505
 506 GType
 507 calf_vumeter_get_type (void)
 508 {
 509     static GType type = 0;
 510     if (!type) {
 511         static const GTypeInfo type_info = {
 512             sizeof(CalfVUMeterClass),
 513             NULL, /* base_init */
 514             NULL, /* base_finalize */
 515             (GClassInitFunc)calf_vumeter_class_init,
 516             NULL, /* class_finalize */
 517             NULL, /* class_data */
 518             sizeof(CalfVUMeter),
 519             0,    /* n_preallocs */
 520             (GInstanceInitFunc)calf_vumeter_init
 521         };
 522
 523         GTypeInfo *type_info_copy = new GTypeInfo(type_info);
 524
 525         for (int i = 0; ; i++) {
 526             char *name = g_strdup_printf("CalfVUMeter%u%d", ((unsigned int)(intptr_t)calf_vumeter_class_init) >> 16, i);
 527             if (g_type_from_name(name)) {
 528                 free(name);
 529                 continue;
 530             }
 531             type = g_type_register_static( GTK_TYPE_DRAWING_AREA,
 532                                            name,
 533                                            type_info_copy,
 534                                            (GTypeFlags)0);
 535             free(name);
 536             break;
 537         }
 538     }
 539     return type;
 540 }
 541
 542 extern void calf_vumeter_set_value(CalfVUMeter *meter, float value)
 543 {
 544     if (value != meter->value)
 545     {
 546         meter->value = value;
 547         gtk_widget_queue_draw(GTK_WIDGET(meter));
 548     }
 549 }
 550
 551 extern float calf_vumeter_get_value(CalfVUMeter *meter)
 552 {
 553     return meter->value;
 554 }
 555
 556 extern void calf_vumeter_set_mode(CalfVUMeter *meter, CalfVUMeterMode mode)
 557 {
 558     if (mode != meter->mode)
 559     {
 560         meter->mode = mode;
 561         gtk_widget_queue_draw(GTK_WIDGET(meter));
 562     }
 563 }
 564
 565 extern CalfVUMeterMode calf_vumeter_get_mode(CalfVUMeter *meter)
 566 {
 567     return meter->mode;
 568 }
 569
 570 ///////////////////////////////////////// knob ///////////////////////////////////////////////
 571
 572 static gboolean
 573 calf_knob_expose (GtkWidget *widget, GdkEventExpose *event)
 574 {
 575     g_assert(CALF_IS_KNOB(widget));
 576
 577     CalfKnob *self = CALF_KNOB(widget);
 578     GdkWindow *window = widget->window;
 579     GtkAdjustment *adj = gtk_range_get_adjustment(GTK_RANGE(widget));
 580
 581     // printf("adjustment = %p value = %f\n", adj, adj->value);
 582     int ox = widget->allocation.x, oy = widget->allocation.y;
 583
 584     ox += (widget->allocation.width - 40) / 2;
 585     oy += (widget->allocation.height - 40) / 2;
 586
 587     int phase = (int)((adj->value - adj->lower) * 64 / (adj->upper - adj->lower));
 588     // skip middle phase except for true middle value
 589     if (self->knob_type == 1 && phase == 32) {
 590         double pt = (adj->value - adj->lower) * 2.0 / (adj->upper - adj->lower) - 1.0;
 591         if (pt < 0)
 592             phase = 31;
 593         if (pt > 0)
 594             phase = 33;
 595     }
 596     // endless knob: skip 90deg highlights unless the value is really a multiple of 90deg
 597     if (self->knob_type == 3 && !(phase % 16)) {
 598         if (phase == 64)
 599             phase = 0;
 600         double nom = adj->lower + phase * (adj->upper - adj->lower) / 64.0;
 601         double diff = (adj->value - nom) / (adj->upper - adj->lower);
 602         if (diff > 0.0001)
 603             phase = (phase + 1) % 64;
 604         if (diff < -0.0001)
 605             phase = (phase + 63) % 64;
 606     }
 607     gdk_draw_pixbuf(GDK_DRAWABLE(widget->window), widget->style->fg_gc[0], CALF_KNOB_CLASS(GTK_OBJECT_GET_CLASS(widget))->knob_image, phase * 40, self->knob_type * 40, ox, oy, 40, 40, GDK_RGB_DITHER_NORMAL, 0, 0);
 608     // printf("exposed %p %d+%d\n", widget->window, widget->allocation.x, widget->allocation.y);
 609     if (gtk_widget_is_focus(widget))
 610     {
 611         gtk_paint_focus(widget->style, window, GTK_STATE_NORMAL, NULL, widget, NULL, ox, oy, 40, 40);
 612     }
 613
 614     return TRUE;
 615 }
 616
 617 static void
 618 calf_knob_size_request (GtkWidget *widget,
 619                            GtkRequisition *requisition)
 620 {
 621     g_assert(CALF_IS_KNOB(widget));
 622
 623     // width/height is hardwired at 40px now
 624     requisition->width = 40;
 625     requisition->height = 40;
 626 }
 627
 628 static void
 629 calf_knob_incr (GtkWidget *widget, int dir_down)
 630 {
 631     g_assert(CALF_IS_KNOB(widget));
 632     CalfKnob *self = CALF_KNOB(widget);
 633     GtkAdjustment *adj = gtk_range_get_adjustment(GTK_RANGE(widget));
 634
 635     int oldstep = (int)(0.5f + (adj->value - adj->lower) / adj->step_increment);
 636     int step;
 637     int nsteps = (int)(0.5f + (adj->upper - adj->lower) / adj->step_increment); // less 1 actually
 638     if (dir_down)
 639         step = oldstep - 1;
 640     else
 641         step = oldstep + 1;
 642     if (self->knob_type == 3 && step >= nsteps)
 643         step %= nsteps;
 644     if (self->knob_type == 3 && step < 0)
 645         step = nsteps - (nsteps - step) % nsteps;
 646
 647     // trying to reduce error cumulation here, by counting from lowest or from highest
 648     float value = adj->lower + step * double(adj->upper - adj->lower) / nsteps;
 649     gtk_range_set_value(GTK_RANGE(widget), value);
 650     // printf("step %d:%d nsteps %d value %f:%f\n", oldstep, step, nsteps, oldvalue, value);
 651 }
 652
 653 static gboolean
 654 calf_knob_key_press (GtkWidget *widget, GdkEventKey *event)
 655 {
 656     g_assert(CALF_IS_KNOB(widget));
 657     CalfKnob *self = CALF_KNOB(widget);
 658     GtkAdjustment *adj = gtk_range_get_adjustment(GTK_RANGE(widget));
 659
 660     switch(event->keyval)
 661     {
 662         case GDK_Home:
 663             gtk_range_set_value(GTK_RANGE(widget), adj->lower);
 664             return TRUE;
 665
 666         case GDK_End:
 667             gtk_range_set_value(GTK_RANGE(widget), adj->upper);
 668             return TRUE;
 669
 670         case GDK_Up:
 671             calf_knob_incr(widget, 0);
 672             return TRUE;
 673
 674         case GDK_Down:
 675             calf_knob_incr(widget, 1);
 676             return TRUE;
 677
 678         case GDK_Shift_L:
 679         case GDK_Shift_R:
 680             self->start_value = gtk_range_get_value(GTK_RANGE(widget));
 681             self->start_y = self->last_y;
 682             return TRUE;
 683     }
 684
 685     return FALSE;
 686 }
 687
 688 static gboolean
 689 calf_knob_key_release (GtkWidget *widget, GdkEventKey *event)
 690 {
 691     g_assert(CALF_IS_KNOB(widget));
 692     CalfKnob *self = CALF_KNOB(widget);
 693
 694     if(event->keyval == GDK_Shift_L || event->keyval == GDK_Shift_R)
 695     {
 696         self->start_value = gtk_range_get_value(GTK_RANGE(widget));
 697         self->start_y = self->last_y;
 698         return TRUE;
 699     }
 700
 701     return FALSE;
 702 }
 703
 704 static gboolean
 705 calf_knob_button_press (GtkWidget *widget, GdkEventButton *event)
 706 {
 707     g_assert(CALF_IS_KNOB(widget));
 708     CalfKnob *self = CALF_KNOB(widget);
 709
 710     // CalfKnob *lg = CALF_KNOB(widget);
 711     gtk_widget_grab_focus(widget);
 712     gtk_grab_add(widget);
 713     self->start_x = event->x;
 714     self->start_y = event->y;
 715     self->start_value = gtk_range_get_value(GTK_RANGE(widget));
 716
 717     return TRUE;
 718 }
 719
 720 static gboolean
 721 calf_knob_button_release (GtkWidget *widget, GdkEventButton *event)
 722 {
 723     g_assert(CALF_IS_KNOB(widget));
 724
 725     if (GTK_WIDGET_HAS_GRAB(widget))
 726         gtk_grab_remove(widget);
 727     return FALSE;
 728 }
 729
 730 static inline float endless(float value)
 731 {
 732     if (value >= 0)
 733         return fmod(value, 1.f);
 734     else
 735         return fmod(1.f - fmod(1.f - value, 1.f), 1.f);
 736 }
 737
 738 static inline float deadzone(float value, float incr, float scale)
 739 {
 740     float dzw = 10 / scale;
 741     if (value >= 0.501)
 742         value += dzw;
 743     if (value < 0.499)
 744         value -= dzw;
 745
 746     value += incr;
 747
 748     if (value >= (0.5 - dzw) && value <= (0.5 + dzw))
 749         return 0.5;
 750     if (value < 0.5)
 751         return value + dzw;
 752     return value - dzw;
 753 }
 754
 755 static gboolean
 756 calf_knob_pointer_motion (GtkWidget *widget, GdkEventMotion *event)
 757 {
 758     g_assert(CALF_IS_KNOB(widget));
 759     CalfKnob *self = CALF_KNOB(widget);
 760
 761     float scale = (event->state & GDK_SHIFT_MASK) ? 1000 : 100;
 762     gboolean moved = FALSE;
 763
 764     if (GTK_WIDGET_HAS_GRAB(widget))
 765     {
 766         if (self->knob_type == 3)
 767         {
 768             gtk_range_set_value(GTK_RANGE(widget), endless(self->start_value - (event->y - self->start_y) / scale));
 769         }
 770         else
 771         if (self->knob_type == 1)
 772         {
 773             gtk_range_set_value(GTK_RANGE(widget), deadzone(self->start_value, -(event->y - self->start_y) / scale, scale));
 774         }
 775         else
 776         {
 777             gtk_range_set_value(GTK_RANGE(widget), self->start_value - (event->y - self->start_y) / scale);
 778         }
 779         moved = TRUE;
 780     }
 781     self->last_y = event->y;
 782     return moved;
 783 }
 784
 785 static gboolean
 786 calf_knob_scroll (GtkWidget *widget, GdkEventScroll *event)
 787 {
 788     calf_knob_incr(widget, event->direction);
 789     return TRUE;
 790 }
 791
 792 static void
 793 calf_knob_class_init (CalfKnobClass *klass)
 794 {
 795     // GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 796     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 797     widget_class->expose_event = calf_knob_expose;
 798     widget_class->size_request = calf_knob_size_request;
 799     widget_class->button_press_event = calf_knob_button_press;
 800     widget_class->button_release_event = calf_knob_button_release;
 801     widget_class->motion_notify_event = calf_knob_pointer_motion;
 802     widget_class->key_press_event = calf_knob_key_press;
 803     widget_class->key_release_event = calf_knob_key_release;
 804     widget_class->scroll_event = calf_knob_scroll;
 805     GError *error = NULL;
 806     klass->knob_image = gdk_pixbuf_new_from_file(PKGLIBDIR "/knob.png", &error);
 807     g_assert(klass->knob_image != NULL);
 808 }
 809
 810 static void
 811 calf_knob_init (CalfKnob *self)
 812 {
 813     GtkWidget *widget = GTK_WIDGET(self);
 814     GTK_WIDGET_SET_FLAGS (GTK_WIDGET(self), GTK_CAN_FOCUS);
 815     widget->requisition.width = 40;
 816     widget->requisition.height = 40;
 817 }
 818
 819 GtkWidget *
 820 calf_knob_new()
 821 {
 822     GtkAdjustment *adj = (GtkAdjustment *)gtk_adjustment_new(0, 0, 1, 0.01, 0.5, 0);
 823     return calf_knob_new_with_adjustment(adj);
 824 }
 825
 826 static gboolean calf_knob_value_changed(gpointer obj)
 827 {
 828     GtkWidget *widget = (GtkWidget *)obj;
 829     gtk_widget_queue_draw(widget);
 830     return FALSE;
 831 }
 832
 833 GtkWidget *calf_knob_new_with_adjustment(GtkAdjustment *_adjustment)
 834 {
 835     GtkWidget *widget = GTK_WIDGET( g_object_new (CALF_TYPE_KNOB, NULL ));
 836     if (widget) {
 837         gtk_range_set_adjustment(GTK_RANGE(widget), _adjustment);
 838         gtk_signal_connect(GTK_OBJECT(widget), "value-changed", G_CALLBACK(calf_knob_value_changed), widget);
 839     }
 840     return widget;
 841 }
 842
 843 GType
 844 calf_knob_get_type (void)
 845 {
 846     static GType type = 0;
 847     if (!type) {
 848
 849         static const GTypeInfo type_info = {
 850             sizeof(CalfKnobClass),
 851             NULL, /* base_init */
 852             NULL, /* base_finalize */
 853             (GClassInitFunc)calf_knob_class_init,
 854             NULL, /* class_finalize */
 855             NULL, /* class_data */
 856             sizeof(CalfKnob),
 857             0,    /* n_preallocs */
 858             (GInstanceInitFunc)calf_knob_init
 859         };
 860
 861         for (int i = 0; ; i++) {
 862             char *name = g_strdup_printf("CalfKnob%u%d",
 863                 ((unsigned int)(intptr_t)calf_knob_class_init) >> 16, i);
 864             if (g_type_from_name(name)) {
 865                 free(name);
 866                 continue;
 867             }
 868             type = g_type_register_static(GTK_TYPE_RANGE,
 869                                           name,
 870                                           &type_info,
 871                                           (GTypeFlags)0);
 872             free(name);
 873             break;
 874         }
 875     }
 876     return type;
 877 }
 878