144 lines
5.1 KiB
C
144 lines
5.1 KiB
C
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// gcc test_transparence.c -o out `pkg-config --cflags --libs gtk+-3.0` -DUSE_GTK_VERSION_3_0
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// gcc test_transparence.c -o out `pkg-config --cflags --libs gtk+-2.0` -DUSE_GTK_VERSION_2_0
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// includes system, malloc, EXIT_SUCCESS
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#include <stdlib.h>
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// includes fopen, fwrite, fseek, ftell
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#include <stdio.h>
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#include <stdarg.h>
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#include <string.h>
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#include <assert.h>
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#include <gdk/gdkkeysyms.h>
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#include <gtk/gtk.h>
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#include <cairo.h>
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static void screen_changed(GtkWidget *widget, GdkScreen *old_screen, gpointer user_data);
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static gboolean expose(GtkWidget *widget, GdkEventExpose *event, gpointer user_data);
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static void clicked(GtkWindow *win, GdkEventButton *event, gpointer user_data);
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# if USE_GTK_VERSION_3_0
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const GdkRGBA color = { 1.0, 1.0, 0.0, 0.0};
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#endif
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int main(int argc, char **argv)
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{
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gtk_init(&argc, &argv);
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GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
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gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER);
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gtk_window_set_default_size(GTK_WINDOW(window), 400, 400);
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gtk_window_set_title(GTK_WINDOW(window), "Alpha Demo");
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g_signal_connect(G_OBJECT(window), "delete-event", gtk_main_quit, NULL);
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gtk_widget_set_app_paintable(window, TRUE);
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# if USE_GTK_VERSION_3_0
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g_signal_connect(G_OBJECT(window), "draw", G_CALLBACK(expose), NULL);
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# elif USE_GTK_VERSION_2_0
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g_signal_connect(G_OBJECT(window), "expose-event", G_CALLBACK(expose), NULL);
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# endif
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g_signal_connect(G_OBJECT(window), "screen-changed", G_CALLBACK(screen_changed), NULL);
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# if USE_GTK_VERSION_3_0
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GtkStyleContext *context;
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GdkRGBA rgba;
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context = gtk_widget_get_style_context(window);
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gtk_style_context_get_background_color(context, GTK_STATE_FLAG_NORMAL,
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&rgba);
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gtk_widget_override_background_color(window,
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GTK_STATE_FLAG_NORMAL, &rgba);
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/*
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gtk_widget_override_background_color(window,
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GTK_STATE_FLAG_NORMAL,// | GTK_STATE_FLAG_ACTIVE | GTK_STATE_FLAG_PRELIGHT | GTK_STATE_FLAG_SELECTED | GTK_STATE_FLAG_INSENSITIVE | GTK_STATE_FLAG_INCONSISTENT | GTK_STATE_FLAG_FOCUSED,
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&color);
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gtk_widget_override_color(window,
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GTK_STATE_FLAG_NORMAL,// | GTK_STATE_FLAG_ACTIVE | GTK_STATE_FLAG_PRELIGHT | GTK_STATE_FLAG_SELECTED | GTK_STATE_FLAG_INSENSITIVE | GTK_STATE_FLAG_INCONSISTENT | GTK_STATE_FLAG_FOCUSED,
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&color);
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*/
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#endif
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gtk_window_set_decorated(GTK_WINDOW(window), FALSE);
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gtk_widget_add_events(window, GDK_BUTTON_PRESS_MASK);
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g_signal_connect(G_OBJECT(window), "button-press-event", G_CALLBACK(clicked), NULL);
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GtkWidget* fixed_container = gtk_fixed_new();
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gtk_container_add(GTK_CONTAINER(window), fixed_container);
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GtkWidget* button = gtk_button_new_with_label("button1");
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gtk_widget_set_size_request(button, 100, 100);
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gtk_container_add(GTK_CONTAINER(fixed_container), button);
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screen_changed(window, NULL, NULL);
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gtk_widget_show_all(window);
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gtk_main();
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return 0;
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}
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gboolean supports_alpha = FALSE;
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static void screen_changed(GtkWidget *widget, GdkScreen *old_screen, gpointer userdata)
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{
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/* To check if the display supports alpha channels, get the colormap */
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# ifdef USE_GTK_VERSION_2_0
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GdkScreen *screen = gtk_widget_get_screen(widget);
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GdkColormap *colormap = gdk_screen_get_rgba_colormap(screen);
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if (!colormap)
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{
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printf("Your screen does not support alpha channels!\n");
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colormap = gdk_screen_get_rgb_colormap(screen);
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supports_alpha = FALSE;
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}
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else
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{
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printf("Your screen supports alpha channels!\n");
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supports_alpha = TRUE;
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}
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gtk_widget_set_colormap(widget, colormap);
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#endif
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/*
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gtk_widget_override_background_color(widget,
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GTK_STATE_FLAG_NORMAL,// | GTK_STATE_FLAG_ACTIVE | GTK_STATE_FLAG_PRELIGHT | GTK_STATE_FLAG_SELECTED | GTK_STATE_FLAG_INSENSITIVE | GTK_STATE_FLAG_INCONSISTENT | GTK_STATE_FLAG_FOCUSED,
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&color);
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gtk_widget_override_color(widget,
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GTK_STATE_FLAG_NORMAL,// | GTK_STATE_FLAG_ACTIVE | GTK_STATE_FLAG_PRELIGHT | GTK_STATE_FLAG_SELECTED | GTK_STATE_FLAG_INSENSITIVE | GTK_STATE_FLAG_INCONSISTENT | GTK_STATE_FLAG_FOCUSED,
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&color);
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*/
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}
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static gboolean expose(GtkWidget *widget, GdkEventExpose *event, gpointer userdata)
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{
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return FALSE;
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# if USE_GTK_VERSION_3_0
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cairo_t *cr = gdk_cairo_create(gtk_widget_get_window(widget));
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# elif USE_GTK_VERSION_2_0
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cairo_t *cr = gdk_cairo_create(widget->window);
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# endif
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if (TRUE == supports_alpha)
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cairo_set_source_rgba (cr, 0.0, 0.0, 1.0, 0.3); /* transparent */
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else
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cairo_set_source_rgb (cr, 1.0, 0.0, 0.0); /* opaque white */
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/* draw the background */
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cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
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cairo_paint (cr);
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cairo_destroy(cr);
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return FALSE;
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}
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static void clicked(GtkWindow *win, GdkEventButton *event, gpointer user_data)
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{
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/* toggle window manager frames */
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gtk_window_set_decorated(win, !gtk_window_get_decorated(win));
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}
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