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-1;
 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 void calf_line_graph_update_if(CalfLineGraph *graph)
 262 {
 263     g_assert(CALF_IS_LINE_GRAPH(graph));
 264     int generation = 0;
 265     if (graph->source)
 266     {
 267         int subgraph, dot, gridline;
 268         generation = graph->source->get_changed_offsets(graph->last_generation, subgraph, dot, gridline);
 269         if (subgraph == INT_MAX && dot == INT_MAX && gridline == INT_MAX)
 270             return;
 271         gtk_widget_queue_draw(GTK_WIDGET(graph));
 272     }
 273 }
 274
 275 static void
 276 calf_line_graph_size_request (GtkWidget *widget,
 277                            GtkRequisition *requisition)
 278 {
 279     g_assert(CALF_IS_LINE_GRAPH(widget));
 280
 281     // CalfLineGraph *lg = CALF_LINE_GRAPH(widget);
 282 }
 283
 284 static void
 285 calf_line_graph_size_allocate (GtkWidget *widget,
 286                            GtkAllocation *allocation)
 287 {
 288     g_assert(CALF_IS_LINE_GRAPH(widget));
 289     CalfLineGraph *lg = CALF_LINE_GRAPH(widget);
 290
 291     GtkWidgetClass *parent_class = (GtkWidgetClass *) g_type_class_peek_parent( CALF_LINE_GRAPH_GET_CLASS( lg ) );
 292
 293     if( lg->cache_surface )
 294         cairo_surface_destroy( lg->cache_surface );
 295     lg->cache_surface = NULL;
 296
 297     widget->allocation = *allocation;
 298     GtkAllocation &a = widget->allocation;
 299     if (lg->is_square)
 300     {
 301         if (a.width > a.height)
 302         {
 303             a.x += (a.width - a.height) / 2;
 304             a.width = a.height;
 305         }
 306         if (a.width < a.height)
 307         {
 308             a.y += (a.height - a.width) / 2;
 309             a.height = a.width;
 310         }
 311     }
 312     parent_class->size_allocate( widget, &a );
 313 }
 314
 315 static void
 316 calf_line_graph_class_init (CalfLineGraphClass *klass)
 317 {
 318     // GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 319     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 320     widget_class->expose_event = calf_line_graph_expose;
 321     widget_class->size_request = calf_line_graph_size_request;
 322     widget_class->size_allocate = calf_line_graph_size_allocate;
 323 }
 324
 325 static void
 326 calf_line_graph_init (CalfLineGraph *self)
 327 {
 328     GtkWidget *widget = GTK_WIDGET(self);
 329     widget->requisition.width = 40;
 330     widget->requisition.height = 40;
 331     self->cache_surface = NULL;
 332     self->last_generation = 0;
 333 }
 334
 335 GtkWidget *
 336 calf_line_graph_new()
 337 {
 338     return GTK_WIDGET( g_object_new (CALF_TYPE_LINE_GRAPH, NULL ));
 339 }
 340
 341 GType
 342 calf_line_graph_get_type (void)
 343 {
 344     static GType type = 0;
 345     if (!type) {
 346         static const GTypeInfo type_info = {
 347             sizeof(CalfLineGraphClass),
 348             NULL, /* base_init */
 349             NULL, /* base_finalize */
 350             (GClassInitFunc)calf_line_graph_class_init,
 351             NULL, /* class_finalize */
 352             NULL, /* class_data */
 353             sizeof(CalfLineGraph),
 354             0,    /* n_preallocs */
 355             (GInstanceInitFunc)calf_line_graph_init
 356         };
 357
 358         GTypeInfo *type_info_copy = new GTypeInfo(type_info);
 359
 360         for (int i = 0; ; i++) {
 361             char *name = g_strdup_printf("CalfLineGraph%u%d", ((unsigned int)(intptr_t)calf_line_graph_class_init) >> 16, i);
 362             if (g_type_from_name(name)) {
 363                 free(name);
 364                 continue;
 365             }
 366             type = g_type_register_static( GTK_TYPE_DRAWING_AREA,
 367                                            name,
 368                                            type_info_copy,
 369                                            (GTypeFlags)0);
 370             free(name);
 371             break;
 372         }
 373     }
 374     return type;
 375 }
 376
 377 ///////////////////////////////////////// vu meter ///////////////////////////////////////////////
 378
 379 static gboolean
 380 calf_vumeter_expose (GtkWidget *widget, GdkEventExpose *event)
 381 {
 382     g_assert(CALF_IS_VUMETER(widget));
 383
 384
 385     CalfVUMeter *vu = CALF_VUMETER(widget);
 386     //int ox = widget->allocation.x + 1, oy = widget->allocation.y + 1;
 387     int ox = 1, oy = 1;
 388     int sx = widget->allocation.width - 2, sy = widget->allocation.height - 2;
 389
 390     cairo_t *c = gdk_cairo_create(GDK_DRAWABLE(widget->window));
 391
 392     if( vu->cache_surface == NULL ) {
 393         // looks like its either first call or the widget has been resized.
 394         // create the cache_surface.
 395         cairo_surface_t *window_surface = cairo_get_target( c );
 396         vu->cache_surface = cairo_surface_create_similar( window_surface,
 397                                                           CAIRO_CONTENT_COLOR,
 398                                                           widget->allocation.width,
 399                                                           widget->allocation.height );
 400
 401         // And render the meterstuff again.
 402
 403         cairo_t *cache_cr = cairo_create( vu->cache_surface );
 404         GdkColor sc = { 0, 0, 0, 0 };
 405         gdk_cairo_set_source_color(cache_cr, &sc);
 406         cairo_rectangle(cache_cr, ox, oy, sx, sy);
 407         cairo_fill(cache_cr);
 408         cairo_set_line_width(cache_cr, 1);
 409
 410         for (int x = ox; x <= ox + sx; x += 3)
 411         {
 412             float ts = (x - ox) * 1.0 / sx;
 413             float r = 0.f, g = 0.f, b = 0.f;
 414             switch(vu->mode)
 415             {
 416                 case VU_STANDARD:
 417                 default:
 418                     if (ts < 0.75)
 419                         r = ts / 0.75, g = 1, b = 0;
 420                     else
 421                         r = 1, g = 1 - (ts - 0.75) / 0.25, b = 0;
 422                     //                if (vu->value < ts || vu->value <= 0)
 423                     //                    r *= 0.5, g *= 0.5, b *= 0.5;
 424                     break;
 425                 case VU_MONOCHROME_REVERSE:
 426                     r = 1, g = 1, b = 0;
 427                     //                if (!(vu->value < ts) || vu->value >= 1.0)
 428                     //                    r *= 0.5, g *= 0.5, b *= 0.5;
 429                     break;
 430                 case VU_MONOCHROME:
 431                     r = 1, g = 1, b = 0;
 432                     //                if (vu->value < ts || vu->value <= 0)
 433                     //                    r *= 0.5, g *= 0.5, b *= 0.5;
 434                     break;
 435             }
 436             GdkColor sc2 = { 0, (guint16)(65535 * r), (guint16)(65535 * g), (guint16)(65535 * b) };
 437             gdk_cairo_set_source_color(cache_cr, &sc2);
 438             cairo_move_to(cache_cr, x, oy);
 439             cairo_line_to(cache_cr, x, oy + sy + 1);
 440             cairo_move_to(cache_cr, x, oy + sy);
 441             cairo_line_to(cache_cr, x, oy );
 442             cairo_stroke(cache_cr);
 443         }
 444         cairo_destroy( cache_cr );
 445     }
 446
 447     cairo_set_source_surface( c, vu->cache_surface, 0,0 );
 448     cairo_paint( c );
 449     cairo_set_source_rgba( c, 0,0,0, 0.5 );
 450
 451     if( vu->mode == VU_MONOCHROME_REVERSE )
 452         cairo_rectangle( c, ox,oy, vu->value * (sx-ox) + 1, sy-oy+1 );
 453     else
 454         cairo_rectangle( c, ox + vu->value * (sx-ox), oy, sx-ox+1, sy-oy+1 );
 455
 456     cairo_fill( c );
 457
 458
 459
 460     cairo_destroy(c);
 461
 462     gtk_paint_shadow(widget->style, widget->window, GTK_STATE_NORMAL, GTK_SHADOW_IN, NULL, widget, NULL, ox - 1, oy - 1, sx + 2, sy + 2);
 463     //printf("exposed %p %d+%d\n", widget->window, widget->allocation.x, widget->allocation.y);
 464
 465     return TRUE;
 466 }
 467
 468 static void
 469 calf_vumeter_size_request (GtkWidget *widget,
 470                            GtkRequisition *requisition)
 471 {
 472     g_assert(CALF_IS_VUMETER(widget));
 473
 474     requisition->width = 50;
 475     requisition->height = 14;
 476 }
 477
 478 static void
 479 calf_vumeter_size_allocate (GtkWidget *widget,
 480                            GtkAllocation *allocation)
 481 {
 482     g_assert(CALF_IS_VUMETER(widget));
 483     CalfVUMeter *vu = CALF_VUMETER(widget);
 484
 485     GtkWidgetClass *parent_class = (GtkWidgetClass *) g_type_class_peek_parent( CALF_VUMETER_GET_CLASS( vu ) );
 486
 487     parent_class->size_allocate( widget, allocation );
 488
 489     if( vu->cache_surface )
 490         cairo_surface_destroy( vu->cache_surface );
 491     vu->cache_surface = NULL;
 492 }
 493
 494 static void
 495 calf_vumeter_class_init (CalfVUMeterClass *klass)
 496 {
 497     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 498     widget_class->expose_event = calf_vumeter_expose;
 499     widget_class->size_request = calf_vumeter_size_request;
 500     widget_class->size_allocate = calf_vumeter_size_allocate;
 501 }
 502
 503 static void
 504 calf_vumeter_init (CalfVUMeter *self)
 505 {
 506     GtkWidget *widget = GTK_WIDGET(self);
 507     //GTK_WIDGET_SET_FLAGS (widget, GTK_NO_WINDOW);
 508     widget->requisition.width = 50;
 509     widget->requisition.height = 15;
 510     self->value = 0.5;
 511     self->cache_surface = NULL;
 512 }
 513
 514 GtkWidget *
 515 calf_vumeter_new()
 516 {
 517     return GTK_WIDGET( g_object_new (CALF_TYPE_VUMETER, NULL ));
 518 }
 519
 520 GType
 521 calf_vumeter_get_type (void)
 522 {
 523     static GType type = 0;
 524     if (!type) {
 525         static const GTypeInfo type_info = {
 526             sizeof(CalfVUMeterClass),
 527             NULL, /* base_init */
 528             NULL, /* base_finalize */
 529             (GClassInitFunc)calf_vumeter_class_init,
 530             NULL, /* class_finalize */
 531             NULL, /* class_data */
 532             sizeof(CalfVUMeter),
 533             0,    /* n_preallocs */
 534             (GInstanceInitFunc)calf_vumeter_init
 535         };
 536
 537         GTypeInfo *type_info_copy = new GTypeInfo(type_info);
 538
 539         for (int i = 0; ; i++) {
 540             char *name = g_strdup_printf("CalfVUMeter%u%d", ((unsigned int)(intptr_t)calf_vumeter_class_init) >> 16, i);
 541             if (g_type_from_name(name)) {
 542                 free(name);
 543                 continue;
 544             }
 545             type = g_type_register_static( GTK_TYPE_DRAWING_AREA,
 546                                            name,
 547                                            type_info_copy,
 548                                            (GTypeFlags)0);
 549             free(name);
 550             break;
 551         }
 552     }
 553     return type;
 554 }
 555
 556 extern void calf_vumeter_set_value(CalfVUMeter *meter, float value)
 557 {
 558     if (value != meter->value)
 559     {
 560         meter->value = value;
 561         gtk_widget_queue_draw(GTK_WIDGET(meter));
 562     }
 563 }
 564
 565 extern float calf_vumeter_get_value(CalfVUMeter *meter)
 566 {
 567     return meter->value;
 568 }
 569
 570 extern void calf_vumeter_set_mode(CalfVUMeter *meter, CalfVUMeterMode mode)
 571 {
 572     if (mode != meter->mode)
 573     {
 574         meter->mode = mode;
 575         gtk_widget_queue_draw(GTK_WIDGET(meter));
 576     }
 577 }
 578
 579 extern CalfVUMeterMode calf_vumeter_get_mode(CalfVUMeter *meter)
 580 {
 581     return meter->mode;
 582 }
 583
 584 ///////////////////////////////////////// knob ///////////////////////////////////////////////
 585
 586 static gboolean
 587 calf_knob_expose (GtkWidget *widget, GdkEventExpose *event)
 588 {
 589     g_assert(CALF_IS_KNOB(widget));
 590
 591     CalfKnob *self = CALF_KNOB(widget);
 592     GdkWindow *window = widget->window;
 593     GtkAdjustment *adj = gtk_range_get_adjustment(GTK_RANGE(widget));
 594
 595     // printf("adjustment = %p value = %f\n", adj, adj->value);
 596     int ox = widget->allocation.x, oy = widget->allocation.y;
 597
 598     ox += (widget->allocation.width - 40) / 2;
 599     oy += (widget->allocation.height - 40) / 2;
 600
 601     int phase = (int)((adj->value - adj->lower) * 64 / (adj->upper - adj->lower));
 602     // skip middle phase except for true middle value
 603     if (self->knob_type == 1 && phase == 32) {
 604         double pt = (adj->value - adj->lower) * 2.0 / (adj->upper - adj->lower) - 1.0;
 605         if (pt < 0)
 606             phase = 31;
 607         if (pt > 0)
 608             phase = 33;
 609     }
 610     // endless knob: skip 90deg highlights unless the value is really a multiple of 90deg
 611     if (self->knob_type == 3 && !(phase % 16)) {
 612         if (phase == 64)
 613             phase = 0;
 614         double nom = adj->lower + phase * (adj->upper - adj->lower) / 64.0;
 615         double diff = (adj->value - nom) / (adj->upper - adj->lower);
 616         if (diff > 0.0001)
 617             phase = (phase + 1) % 64;
 618         if (diff < -0.0001)
 619             phase = (phase + 63) % 64;
 620     }
 621     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);
 622     // printf("exposed %p %d+%d\n", widget->window, widget->allocation.x, widget->allocation.y);
 623     if (gtk_widget_is_focus(widget))
 624     {
 625         gtk_paint_focus(widget->style, window, GTK_STATE_NORMAL, NULL, widget, NULL, ox, oy, 40, 40);
 626     }
 627
 628     return TRUE;
 629 }
 630
 631 static void
 632 calf_knob_size_request (GtkWidget *widget,
 633                            GtkRequisition *requisition)
 634 {
 635     g_assert(CALF_IS_KNOB(widget));
 636
 637     // width/height is hardwired at 40px now
 638     requisition->width = 40;
 639     requisition->height = 40;
 640 }
 641
 642 static void
 643 calf_knob_incr (GtkWidget *widget, int dir_down)
 644 {
 645     g_assert(CALF_IS_KNOB(widget));
 646     CalfKnob *self = CALF_KNOB(widget);
 647     GtkAdjustment *adj = gtk_range_get_adjustment(GTK_RANGE(widget));
 648
 649     int oldstep = (int)(0.5f + (adj->value - adj->lower) / adj->step_increment);
 650     int step;
 651     int nsteps = (int)(0.5f + (adj->upper - adj->lower) / adj->step_increment); // less 1 actually
 652     if (dir_down)
 653         step = oldstep - 1;
 654     else
 655         step = oldstep + 1;
 656     if (self->knob_type == 3 && step >= nsteps)
 657         step %= nsteps;
 658     if (self->knob_type == 3 && step < 0)
 659         step = nsteps - (nsteps - step) % nsteps;
 660
 661     // trying to reduce error cumulation here, by counting from lowest or from highest
 662     float value = adj->lower + step * double(adj->upper - adj->lower) / nsteps;
 663     gtk_range_set_value(GTK_RANGE(widget), value);
 664     // printf("step %d:%d nsteps %d value %f:%f\n", oldstep, step, nsteps, oldvalue, value);
 665 }
 666
 667 static gboolean
 668 calf_knob_key_press (GtkWidget *widget, GdkEventKey *event)
 669 {
 670     g_assert(CALF_IS_KNOB(widget));
 671     CalfKnob *self = CALF_KNOB(widget);
 672     GtkAdjustment *adj = gtk_range_get_adjustment(GTK_RANGE(widget));
 673
 674     switch(event->keyval)
 675     {
 676         case GDK_Home:
 677             gtk_range_set_value(GTK_RANGE(widget), adj->lower);
 678             return TRUE;
 679
 680         case GDK_End:
 681             gtk_range_set_value(GTK_RANGE(widget), adj->upper);
 682             return TRUE;
 683
 684         case GDK_Up:
 685             calf_knob_incr(widget, 0);
 686             return TRUE;
 687
 688         case GDK_Down:
 689             calf_knob_incr(widget, 1);
 690             return TRUE;
 691
 692         case GDK_Shift_L:
 693         case GDK_Shift_R:
 694             self->start_value = gtk_range_get_value(GTK_RANGE(widget));
 695             self->start_y = self->last_y;
 696             return TRUE;
 697     }
 698
 699     return FALSE;
 700 }
 701
 702 static gboolean
 703 calf_knob_key_release (GtkWidget *widget, GdkEventKey *event)
 704 {
 705     g_assert(CALF_IS_KNOB(widget));
 706     CalfKnob *self = CALF_KNOB(widget);
 707
 708     if(event->keyval == GDK_Shift_L || event->keyval == GDK_Shift_R)
 709     {
 710         self->start_value = gtk_range_get_value(GTK_RANGE(widget));
 711         self->start_y = self->last_y;
 712         return TRUE;
 713     }
 714
 715     return FALSE;
 716 }
 717
 718 static gboolean
 719 calf_knob_button_press (GtkWidget *widget, GdkEventButton *event)
 720 {
 721     g_assert(CALF_IS_KNOB(widget));
 722     CalfKnob *self = CALF_KNOB(widget);
 723
 724     // CalfKnob *lg = CALF_KNOB(widget);
 725     gtk_widget_grab_focus(widget);
 726     gtk_grab_add(widget);
 727     self->start_x = event->x;
 728     self->start_y = event->y;
 729     self->start_value = gtk_range_get_value(GTK_RANGE(widget));
 730
 731     return TRUE;
 732 }
 733
 734 static gboolean
 735 calf_knob_button_release (GtkWidget *widget, GdkEventButton *event)
 736 {
 737     g_assert(CALF_IS_KNOB(widget));
 738
 739     if (GTK_WIDGET_HAS_GRAB(widget))
 740         gtk_grab_remove(widget);
 741     return FALSE;
 742 }
 743
 744 static inline float endless(float value)
 745 {
 746     if (value >= 0)
 747         return fmod(value, 1.f);
 748     else
 749         return fmod(1.f - fmod(1.f - value, 1.f), 1.f);
 750 }
 751
 752 static inline float deadzone(float value, float incr, float scale)
 753 {
 754     float dzw = 10 / scale;
 755     if (value >= 0.501)
 756         value += dzw;
 757     if (value < 0.499)
 758         value -= dzw;
 759
 760     value += incr;
 761
 762     if (value >= (0.5 - dzw) && value <= (0.5 + dzw))
 763         return 0.5;
 764     if (value < 0.5)
 765         return value + dzw;
 766     return value - dzw;
 767 }
 768
 769 static gboolean
 770 calf_knob_pointer_motion (GtkWidget *widget, GdkEventMotion *event)
 771 {
 772     g_assert(CALF_IS_KNOB(widget));
 773     CalfKnob *self = CALF_KNOB(widget);
 774
 775     float scale = (event->state & GDK_SHIFT_MASK) ? 1000 : 100;
 776     gboolean moved = FALSE;
 777
 778     if (GTK_WIDGET_HAS_GRAB(widget))
 779     {
 780         if (self->knob_type == 3)
 781         {
 782             gtk_range_set_value(GTK_RANGE(widget), endless(self->start_value - (event->y - self->start_y) / scale));
 783         }
 784         else
 785         if (self->knob_type == 1)
 786         {
 787             gtk_range_set_value(GTK_RANGE(widget), deadzone(self->start_value, -(event->y - self->start_y) / scale, scale));
 788         }
 789         else
 790         {
 791             gtk_range_set_value(GTK_RANGE(widget), self->start_value - (event->y - self->start_y) / scale);
 792         }
 793         moved = TRUE;
 794     }
 795     self->last_y = event->y;
 796     return moved;
 797 }
 798
 799 static gboolean
 800 calf_knob_scroll (GtkWidget *widget, GdkEventScroll *event)
 801 {
 802     calf_knob_incr(widget, event->direction);
 803     return TRUE;
 804 }
 805
 806 static void
 807 calf_knob_class_init (CalfKnobClass *klass)
 808 {
 809     // GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 810     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 811     widget_class->expose_event = calf_knob_expose;
 812     widget_class->size_request = calf_knob_size_request;
 813     widget_class->button_press_event = calf_knob_button_press;
 814     widget_class->button_release_event = calf_knob_button_release;
 815     widget_class->motion_notify_event = calf_knob_pointer_motion;
 816     widget_class->key_press_event = calf_knob_key_press;
 817     widget_class->key_release_event = calf_knob_key_release;
 818     widget_class->scroll_event = calf_knob_scroll;
 819     GError *error = NULL;
 820     klass->knob_image = gdk_pixbuf_new_from_file(PKGLIBDIR "/knob.png", &error);
 821     g_assert(klass->knob_image != NULL);
 822 }
 823
 824 static void
 825 calf_knob_init (CalfKnob *self)
 826 {
 827     GtkWidget *widget = GTK_WIDGET(self);
 828     GTK_WIDGET_SET_FLAGS (GTK_WIDGET(self), GTK_CAN_FOCUS);
 829     widget->requisition.width = 40;
 830     widget->requisition.height = 40;
 831 }
 832
 833 GtkWidget *
 834 calf_knob_new()
 835 {
 836     GtkAdjustment *adj = (GtkAdjustment *)gtk_adjustment_new(0, 0, 1, 0.01, 0.5, 0);
 837     return calf_knob_new_with_adjustment(adj);
 838 }
 839
 840 static gboolean calf_knob_value_changed(gpointer obj)
 841 {
 842     GtkWidget *widget = (GtkWidget *)obj;
 843     gtk_widget_queue_draw(widget);
 844     return FALSE;
 845 }
 846
 847 GtkWidget *calf_knob_new_with_adjustment(GtkAdjustment *_adjustment)
 848 {
 849     GtkWidget *widget = GTK_WIDGET( g_object_new (CALF_TYPE_KNOB, NULL ));
 850     if (widget) {
 851         gtk_range_set_adjustment(GTK_RANGE(widget), _adjustment);
 852         gtk_signal_connect(GTK_OBJECT(widget), "value-changed", G_CALLBACK(calf_knob_value_changed), widget);
 853     }
 854     return widget;
 855 }
 856
 857 GType
 858 calf_knob_get_type (void)
 859 {
 860     static GType type = 0;
 861     if (!type) {
 862
 863         static const GTypeInfo type_info = {
 864             sizeof(CalfKnobClass),
 865             NULL, /* base_init */
 866             NULL, /* base_finalize */
 867             (GClassInitFunc)calf_knob_class_init,
 868             NULL, /* class_finalize */
 869             NULL, /* class_data */
 870             sizeof(CalfKnob),
 871             0,    /* n_preallocs */
 872             (GInstanceInitFunc)calf_knob_init
 873         };
 874
 875         for (int i = 0; ; i++) {
 876             char *name = g_strdup_printf("CalfKnob%u%d",
 877                 ((unsigned int)(intptr_t)calf_knob_class_init) >> 16, i);
 878             if (g_type_from_name(name)) {
 879                 free(name);
 880                 continue;
 881             }
 882             type = g_type_register_static(GTK_TYPE_RANGE,
 883                                           name,
 884                                           &type_info,
 885                                           (GTypeFlags)0);
 886             free(name);
 887             break;
 888         }
 889     }
 890     return type;
 891 }
 892