src/ctl_keyboard.cpp

   1 /* Calf DSP Library
   2  * Barely started keyboard widget. Planned to be usable as
   3  * a ruler for curves, and possibly as input widget in future
   4  * as well (that's what event sink interface is for, at least).
   5  *
   6  * Copyright (C) 2008 Krzysztof Foltman
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General
  19  * Public License along with this program; if not, write to the
  20  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21  * Boston, MA  02110-1301  USA
  22  */
  23 #include <calf/ctl_keyboard.h>
  24 #include <stdint.h>
  25 #include <malloc.h>
  26
  27 static const int semitones_b[] = { 1, 3, -1, 6, 8, 10, -1 };
  28 static const int semitones_w[] = { 0, 2, 4, 5, 7, 9, 11 };
  29
  30
  31 GtkWidget *
  32 calf_keyboard_new()
  33 {
  34     GtkWidget *widget = GTK_WIDGET( g_object_new (CALF_TYPE_KEYBOARD, NULL ));
  35     return widget;
  36 }
  37
  38 static gboolean
  39 calf_keyboard_expose (GtkWidget *widget, GdkEventExpose *event)
  40 {
  41     g_assert(CALF_IS_KEYBOARD(widget));
  42
  43     cairo_pattern_t *pat;
  44     CalfKeyboard *self = CALF_KEYBOARD(widget);
  45     GdkWindow *window = widget->window;
  46     cairo_t *c = gdk_cairo_create(GDK_DRAWABLE(window));
  47     int sy = widget->allocation.height - 1;
  48     cairo_set_line_join(c, CAIRO_LINE_JOIN_MITER);
  49     cairo_set_line_width(c, 1);
  50
  51     for (int i = 0; i < self->nkeys; i++)
  52     {
  53         CalfKeyboard::KeyInfo ki = { 0.5 + 12 * i, 0.5, 12, sy, 12 * (i / 7) + semitones_w[i % 7], false };
  54         cairo_new_path(c);
  55         if (!self->sink->pre_draw(c, ki))
  56         {
  57             cairo_rectangle(c, ki.x, ki.y, ki.width, ki.y + ki.height);
  58
  59             pat = cairo_pattern_create_linear (ki.x, ki.y, ki.x, ki.y + ki.height);
  60             cairo_pattern_add_color_stop_rgb (pat, 0.0, 0.25, 0.25, 0.2);
  61             cairo_pattern_add_color_stop_rgb (pat, 0.1, 0.957, 0.914, 0.925);
  62             cairo_pattern_add_color_stop_rgb (pat, 1.0, 0.796, 0.787, 0.662);
  63             cairo_set_source(c, pat);
  64             cairo_fill(c);
  65
  66             cairo_set_source_rgba(c, 0, 0, 0, 0.5);
  67
  68             if (!self->sink->pre_draw_outline(c, ki))
  69                 cairo_stroke(c);
  70             else
  71                 cairo_new_path(c);
  72             self->sink->post_draw(c, ki);
  73         }
  74     }
  75
  76     for (int i = 0; i < self->nkeys - 1; i++)
  77     {
  78         if ((1 << (i % 7)) & 59)
  79         {
  80             CalfKeyboard::KeyInfo ki = { 8.5 + 12 * i, 0.5, 8, sy * 3 / 5, 12 * (i / 7) + semitones_b[i % 7], true };
  81             cairo_new_path(c);
  82             cairo_rectangle(c, ki.x, ki.y, ki.width, ki.height);
  83 //            gdk_cairo_set_source_color(c, &scBlackKey);
  84             if (!self->sink->pre_draw(c, ki))
  85             {
  86                 pat = cairo_pattern_create_linear (ki.x, ki.y, ki.x, ki.height + ki.y);
  87                 cairo_pattern_add_color_stop_rgb (pat, 0.0, 0, 0, 0);
  88                 cairo_pattern_add_color_stop_rgb (pat, 0.1, 0.27, 0.27, 0.27);
  89                 cairo_pattern_add_color_stop_rgb (pat, 1.0, 0, 0, 0);
  90                 cairo_set_source(c, pat);
  91                 cairo_fill(c);
  92
  93                 pat = cairo_pattern_create_linear (ki.x + 1, ki.y, ki.x + 1, (int)(ki.height * 0.8 + ki.y));
  94                 cairo_pattern_add_color_stop_rgb (pat, 0.0, 0, 0, 0);
  95                 cairo_pattern_add_color_stop_rgb (pat, 0.1, 0.55, 0.55, 0.55);
  96                 cairo_pattern_add_color_stop_rgb (pat, 0.5, 0.45, 0.45, 0.45);
  97                 cairo_pattern_add_color_stop_rgb (pat, 0.5001, 0.35, 0.35, 0.35);
  98                 cairo_pattern_add_color_stop_rgb (pat, 1.0, 0.25, 0.25, 0.25);
  99                 cairo_set_source(c, pat);
 100                 cairo_rectangle(c, ki.x + 1, ki.y, ki.width - 2, (int)(ki.height * 0.8 + ki.y));
 101                 cairo_fill(c);
 102
 103                 self->sink->post_draw(c, ki);
 104             }
 105         }
 106     }
 107
 108     pat = cairo_pattern_create_linear (widget->allocation.x, widget->allocation.y, widget->allocation.x, (int)(widget->allocation.height * 0.2 + widget->allocation.y));
 109     cairo_pattern_add_color_stop_rgba (pat, 0.0, 0, 0, 0, 0.4);
 110     cairo_pattern_add_color_stop_rgba (pat, 1.0, 0, 0, 0, 0);
 111     cairo_rectangle(c, widget->allocation.x, widget->allocation.y, widget->allocation.width, (int)(widget->allocation.height * 0.2));
 112     cairo_set_source(c, pat);
 113     cairo_fill(c);
 114
 115     self->sink->post_all(c);
 116
 117     cairo_destroy(c);
 118
 119     return TRUE;
 120 }
 121
 122 static void
 123 calf_keyboard_realize(GtkWidget *widget)
 124 {
 125     GTK_WIDGET_SET_FLAGS(widget, GTK_REALIZED);
 126
 127     GdkWindowAttr attributes;
 128     attributes.event_mask = GDK_EXPOSURE_MASK | GDK_BUTTON1_MOTION_MASK |
 129         GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK |
 130         GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK;
 131     attributes.x = widget->allocation.x;
 132     attributes.y = widget->allocation.y;
 133     attributes.width = widget->allocation.width;
 134     attributes.height = widget->allocation.height;
 135     attributes.wclass = GDK_INPUT_OUTPUT;
 136     attributes.window_type = GDK_WINDOW_CHILD;
 137
 138     widget->window = gdk_window_new(gtk_widget_get_parent_window (widget), &attributes, GDK_WA_X | GDK_WA_Y);
 139
 140     gdk_window_set_user_data(widget->window, widget);
 141     widget->style = gtk_style_attach(widget->style, widget->window);
 142 }
 143
 144 static void
 145 calf_keyboard_size_request (GtkWidget *widget,
 146                            GtkRequisition *requisition)
 147 {
 148     CalfKeyboard *self = CALF_KEYBOARD(widget);
 149     g_assert(CALF_IS_KEYBOARD(widget));
 150
 151     requisition->width = 12 * self->nkeys + 1;
 152     requisition->height = 40;
 153 }
 154
 155 static void
 156 calf_keyboard_size_allocate (GtkWidget *widget,
 157                            GtkAllocation *allocation)
 158 {
 159     // CalfKeyboard *self = CALF_KEYBOARD(widget);
 160     g_assert(CALF_IS_KEYBOARD(widget));
 161     widget->allocation = *allocation;
 162     widget->allocation.width = widget->requisition.width;
 163
 164     if (GTK_WIDGET_REALIZED(widget))
 165         gdk_window_move_resize(widget->window,
 166             allocation->x + (allocation->width - widget->allocation.width) / 2, allocation->y,
 167             widget->allocation.width, allocation->height );
 168 }
 169
 170 static gboolean
 171 calf_keyboard_key_press (GtkWidget *widget, GdkEventKey *event)
 172 {
 173     g_assert(CALF_IS_KEYBOARD(widget));
 174     CalfKeyboard *self = CALF_KEYBOARD(widget);
 175     if (!self->sink)
 176         return FALSE;
 177     return FALSE;
 178 }
 179
 180 int
 181 calf_keyboard_pos_to_note (CalfKeyboard *kb, int x, int y, int *vel = NULL)
 182 {
 183     // first try black keys
 184     if (y <= kb->parent.allocation.height * 3 / 5 && x >= 0 && (x - 8) % 12 < 8)
 185     {
 186         int blackkey = (x - 8) / 12;
 187         if (blackkey < kb->nkeys && (59 & (1 << (blackkey % 7))))
 188         {
 189             return semitones_b[blackkey % 7] + 12 * (blackkey / 7);
 190         }
 191     }
 192     // if not a black key, then which white one?
 193     int whitekey = x / 12;
 194     // semitones within octave + 12 semitones per octave
 195     return semitones_w[whitekey % 7] + 12 * (whitekey / 7);
 196 }
 197
 198 static gboolean
 199 calf_keyboard_button_press (GtkWidget *widget, GdkEventButton *event)
 200 {
 201     g_assert(CALF_IS_KEYBOARD(widget));
 202     CalfKeyboard *self = CALF_KEYBOARD(widget);
 203     if (!self->interactive)
 204         return FALSE;
 205     gtk_widget_grab_focus(widget);
 206     int vel = 127;
 207     self->last_key = calf_keyboard_pos_to_note(self, (int)event->x, (int)event->y, &vel);
 208     if (self->last_key != -1)
 209         self->sink->note_on(self->last_key, vel);
 210     return FALSE;
 211 }
 212
 213 static gboolean
 214 calf_keyboard_button_release (GtkWidget *widget, GdkEventButton *event)
 215 {
 216     g_assert(CALF_IS_KEYBOARD(widget));
 217     CalfKeyboard *self = CALF_KEYBOARD(widget);
 218     if (!self->interactive)
 219         return FALSE;
 220     if (self->last_key != -1)
 221         self->sink->note_off(self->last_key);
 222     return FALSE;
 223 }
 224
 225 static gboolean
 226 calf_keyboard_pointer_motion (GtkWidget *widget, GdkEventMotion *event)
 227 {
 228     g_assert(CALF_IS_KEYBOARD(widget));
 229     CalfKeyboard *self = CALF_KEYBOARD(widget);
 230     if (!self->interactive)
 231         return FALSE;
 232     int vel = 127;
 233     int key = calf_keyboard_pos_to_note(self, (int)event->x, (int)event->y, &vel);
 234     if (key != self->last_key)
 235     {
 236         if (self->last_key != -1)
 237             self->sink->note_off(self->last_key);
 238         self->last_key = key;
 239         if (self->last_key != -1)
 240             self->sink->note_on(self->last_key, vel);
 241     }
 242     return FALSE;
 243 }
 244
 245 static void
 246 calf_keyboard_class_init (CalfKeyboardClass *klass)
 247 {
 248     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 249     widget_class->realize = calf_keyboard_realize;
 250     widget_class->size_allocate = calf_keyboard_size_allocate;
 251     widget_class->expose_event = calf_keyboard_expose;
 252     widget_class->size_request = calf_keyboard_size_request;
 253     widget_class->button_press_event = calf_keyboard_button_press;
 254     widget_class->button_release_event = calf_keyboard_button_release;
 255     widget_class->motion_notify_event = calf_keyboard_pointer_motion;
 256     widget_class->key_press_event = calf_keyboard_key_press;
 257     // widget_class->scroll_event = calf_keyboard_scroll;
 258 }
 259
 260 static void
 261 calf_keyboard_init (CalfKeyboard *self)
 262 {
 263     static CalfKeyboard::EventAdapter default_sink;
 264     GtkWidget *widget = GTK_WIDGET(self);
 265     g_assert(CALF_IS_KEYBOARD(widget));
 266     GTK_WIDGET_SET_FLAGS (GTK_WIDGET(self), GTK_CAN_FOCUS);
 267     self->nkeys = 7 * 3 + 1;
 268     self->sink = &default_sink;
 269     self->last_key = -1;
 270 }
 271
 272 GType
 273 calf_keyboard_get_type (void)
 274 {
 275     static GType type = 0;
 276     if (!type) {
 277
 278         static const GTypeInfo type_info = {
 279             sizeof(CalfKeyboardClass),
 280             NULL, /* base_init */
 281             NULL, /* base_finalize */
 282             (GClassInitFunc)calf_keyboard_class_init,
 283             NULL, /* class_finalize */
 284             NULL, /* class_data */
 285             sizeof(CalfKeyboard),
 286             0,    /* n_preallocs */
 287             (GInstanceInitFunc)calf_keyboard_init
 288         };
 289
 290         for (int i = 0; ; i++) {
 291             char *name = g_strdup_printf("CalfKeyboard%u%d",
 292                 ((unsigned int)(intptr_t)calf_keyboard_class_init) >> 16, i);
 293             if (g_type_from_name(name)) {
 294                 free(name);
 295                 continue;
 296             }
 297             type = g_type_register_static(GTK_TYPE_WIDGET,
 298                                           name,
 299                                           &type_info,
 300                                           (GTypeFlags)0);
 301             free(name);
 302             break;
 303         }
 304     }
 305     return type;
 306 }
 307