src/led.cpp

   1 /* Calf DSP Library
   2  * Light emitting diode-like control.
   3  *
   4  * Copyright (C) 2008 Krzysztof Foltman
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General
  17  * Public License along with this program; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  19  * Boston, MA 02111-1307, USA.
  20  */
  21 #include <calfwidgets/led.h>
  22 #include <math.h>
  23 #include <stdint.h>
  24 #include <malloc.h>
  25
  26 GtkWidget *
  27 calf_led_new()
  28 {
  29     GtkWidget *widget = GTK_WIDGET( g_object_new (CALF_TYPE_LED, NULL ));
  30     return widget;
  31 }
  32
  33 static gboolean
  34 calf_led_expose (GtkWidget *widget, GdkEventExpose *event)
  35 {
  36     g_assert(CALF_IS_LED(widget));
  37
  38     CalfLed *self = CALF_LED(widget);
  39     GdkWindow *window = widget->window;
  40     cairo_t *c = gdk_cairo_create(GDK_DRAWABLE(window));
  41
  42     gdk_cairo_set_source_color(c, &widget->style->bg[0]);
  43     cairo_rectangle(c, 0, 0, widget->allocation.width, widget->allocation.height);
  44     cairo_fill(c);
  45
  46     int xc = widget->allocation.width / 2;
  47     int yc = widget->allocation.height / 2;
  48
  49     int diameter = (widget->allocation.width < widget->allocation.height ? widget->allocation.width : widget->allocation.height) - 1;
  50
  51     cairo_pattern_t *pt = cairo_pattern_create_radial(xc, yc + diameter / 4, 0, xc, yc, diameter / 2);
  52     cairo_pattern_add_color_stop_rgb(pt, 0.0, self->led_state ? 1.0 : 0.25, 0.0, 0.0);
  53     cairo_pattern_add_color_stop_rgb(pt, 0.5, self->led_state ? 0.75 : 0.2, 0.0, 0.0);
  54     cairo_pattern_add_color_stop_rgb(pt, 1.0, self->led_state ? 0.25 : 0.1, 0.0, 0.0);
  55
  56     cairo_arc(c, xc, yc, diameter / 2, 0, 2 * M_PI);
  57     cairo_set_line_join(c, CAIRO_LINE_JOIN_BEVEL);
  58     cairo_set_source (c, pt);
  59     cairo_fill(c);
  60     cairo_pattern_destroy(pt);
  61
  62     cairo_arc(c, xc, yc, diameter / 2, 0, 2 * M_PI);
  63     cairo_set_line_width(c, 0.5);
  64     cairo_set_source_rgba (c, self->led_state ? 1.0 : 0.3, 0, 0, 0.5);
  65     cairo_stroke(c);
  66
  67     cairo_destroy(c);
  68
  69     return TRUE;
  70 }
  71
  72 static void
  73 calf_led_realize(GtkWidget *widget)
  74 {
  75     GTK_WIDGET_SET_FLAGS(widget, GTK_REALIZED);
  76
  77     GdkWindowAttr attributes;
  78     attributes.event_mask = GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK;
  79     attributes.x = widget->allocation.x;
  80     attributes.y = widget->allocation.y;
  81     attributes.width = widget->allocation.width;
  82     attributes.height = widget->allocation.height;
  83     attributes.wclass = GDK_INPUT_OUTPUT;
  84     attributes.window_type = GDK_WINDOW_CHILD;
  85
  86     widget->window = gdk_window_new(gtk_widget_get_parent_window (widget), &attributes, GDK_WA_X | GDK_WA_Y);
  87
  88     gdk_window_set_user_data(widget->window, widget);
  89     widget->style = gtk_style_attach(widget->style, widget->window);
  90 }
  91
  92 static void
  93 calf_led_size_request (GtkWidget *widget,
  94                            GtkRequisition *requisition)
  95 {
  96     g_assert(CALF_IS_LED(widget));
  97
  98     requisition->width = 12;
  99     requisition->height = 12;
 100 }
 101
 102 static void
 103 calf_led_size_allocate (GtkWidget *widget,
 104                            GtkAllocation *allocation)
 105 {
 106     g_assert(CALF_IS_LED(widget));
 107
 108     widget->allocation = *allocation;
 109
 110     if (GTK_WIDGET_REALIZED(widget))
 111         gdk_window_move_resize(widget->window, allocation->x, allocation->y, allocation->width, allocation->height );
 112 }
 113
 114 static gboolean
 115 calf_led_button_press (GtkWidget *widget, GdkEventButton *event)
 116 {
 117     return TRUE;
 118 }
 119
 120 static void
 121 calf_led_class_init (CalfLedClass *klass)
 122 {
 123     GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
 124     widget_class->realize = calf_led_realize;
 125     widget_class->expose_event = calf_led_expose;
 126     widget_class->size_request = calf_led_size_request;
 127     widget_class->size_allocate = calf_led_size_allocate;
 128     widget_class->button_press_event = calf_led_button_press;
 129 }
 130
 131 static void
 132 calf_led_init (CalfLed *self)
 133 {
 134     // GtkWidget *widget = GTK_WIDGET(self);
 135     // GTK_WIDGET_SET_FLAGS (widget, GTK_CAN_FOCUS);
 136     self->led_state = FALSE;
 137 }
 138
 139 void calf_led_set_state(CalfLed *led, gboolean state)
 140 {
 141     if (state != led->led_state)
 142     {
 143         led->led_state = state;
 144         GtkWidget *widget = GTK_WIDGET (led);
 145         if (GTK_WIDGET_REALIZED(widget))
 146             gtk_widget_queue_draw (widget);
 147     }
 148 }
 149
 150 gboolean calf_led_get_state(CalfLed *led)
 151 {
 152     return led->led_state;
 153 }
 154
 155 GType
 156 calf_led_get_type (void)
 157 {
 158     static GType type = 0;
 159     if (!type) {
 160
 161         static const GTypeInfo type_info = {
 162             sizeof(CalfLedClass),
 163             NULL, /* base_init */
 164             NULL, /* base_finalize */
 165             (GClassInitFunc)calf_led_class_init,
 166             NULL, /* class_finalize */
 167             NULL, /* class_data */
 168             sizeof(CalfLed),
 169             0,    /* n_preallocs */
 170             (GInstanceInitFunc)calf_led_init
 171         };
 172
 173         for (int i = 0; ; i++) {
 174             char *name = g_strdup_printf("CalfLed%u%d",
 175                 ((unsigned int)(intptr_t)calf_led_class_init) >> 16, i);
 176             if (g_type_from_name(name)) {
 177                 free(name);
 178                 continue;
 179             }
 180             type = g_type_register_static(GTK_TYPE_WIDGET,
 181                                           name,
 182                                           &type_info,
 183                                           (GTypeFlags)0);
 184             free(name);
 185             break;
 186         }
 187     }
 188     return type;
 189 }
 190