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/*
* Copyright (C) 1998 Janne Löf <jlof@mail.student.oulu.fi>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <math.h>
#include <gtk/gtk.h>
#include <gtkgl/gtkglarea.h>
#include <GL/gl.h>
#include <string.h>
GLuint fontbase; /* display list base for fonts */
int fontheight;
char *fontname;
gint init(GtkWidget *widget)
{
if (gtk_gl_area_make_current(GTK_GL_AREA(widget))) {
GdkFont *font;
/* set viewport */
glViewport(0,0, widget->allocation.width, widget->allocation.height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0,widget->allocation.width, 0,widget->allocation.height, -1.0, 1.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
/* generate font display lists */
fontbase = glGenLists( 128 );
font = gdk_font_load(fontname);
if (!font) {
g_print("Can't load font '%s'\n", fontname);
gtk_exit(1);
}
gdk_gl_use_gdk_font(font, 0, 128, fontbase);
fontheight = font->ascent+font->descent;
gdk_font_unref(font);
}
return TRUE;
}
/* When widget is exposed it's contents are redrawn. */
gint draw(GtkWidget *widget, GdkEventExpose *event)
{
/* Draw only last expose. */
if (event->count > 0) {
return TRUE;
}
if (gtk_gl_area_make_current(GTK_GL_AREA(widget))) {
int i,j;
/* clear screen */
glClearColor(0,0,1,1);
glClear(GL_COLOR_BUFFER_BIT);
/* Draw some text */
glColor3f(1,1,1);
for (i=1; i<5; i++) {
glRasterPos2f(10, widget->allocation.height-i*fontheight);
for (j=' '; j<='Z'; j++) {
glCallList(fontbase+j);
}
}
/* show font name */
glColor3f(1,1,0);
glRasterPos2f(10,5);
glListBase(fontbase);
glCallLists(strlen(fontname), GL_UNSIGNED_BYTE, fontname);
gdk_gl_wait_gl();
}
return TRUE;
}
/* When glarea widget size changes, viewport size is set to match the new size */
gint reshape(GtkWidget *widget, GdkEventConfigure *event)
{
if (gtk_gl_area_make_current(GTK_GL_AREA(widget))) {
glViewport(0,0, widget->allocation.width, widget->allocation.height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0,widget->allocation.width, 0,widget->allocation.height, -1.0, 1.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
return TRUE;
}
int main(int argc, char **argv)
{
GtkWidget *window,*glarea;
gtk_init(&argc, &argv);
if (argc == 1) {
fontname = "-adobe-helvetica-medium-r-normal--*-120-*-*-*-*-*-*";
} else if (argc == 2) {
fontname = argv[1];
} else if (argc > 2) {
g_print("Usage: gdkfont [font]\n");
return 0;
}
/* Check if OpenGL (GLX extension) is supported. */
if (gdk_gl_query() == FALSE) {
g_print("OpenGL not supported\n");
return 0;
}
/* Create new top level window. */
window = gtk_window_new( GTK_WINDOW_TOPLEVEL);
gtk_window_set_title(GTK_WINDOW(window), "gdkfont");
gtk_container_set_border_width(GTK_CONTAINER(window), 10);
/* Quit form main if got delete event */
gtk_signal_connect(GTK_OBJECT(window), "delete_event",
GTK_SIGNAL_FUNC(gtk_main_quit), NULL);
/* Delete widget before exit */
gtk_quit_add_destroy(1, GTK_OBJECT(window));
/* Create new OpenGL widget. */
glarea = GTK_WIDGET(gtk_gl_area_new_vargs(NULL,
GDK_GL_RGBA,
GDK_GL_RED_SIZE,1,
GDK_GL_GREEN_SIZE,1,
GDK_GL_BLUE_SIZE,1,
GDK_GL_DEPTH_SIZE,1,
GDK_GL_NONE));
gtk_widget_set_events(GTK_WIDGET(glarea),
GDK_EXPOSURE_MASK|
GDK_BUTTON_PRESS_MASK);
/* Connect signal handlers */
gtk_signal_connect(GTK_OBJECT(glarea), "expose_event",
GTK_SIGNAL_FUNC(draw), NULL);
gtk_signal_connect(GTK_OBJECT(glarea), "configure_event",
GTK_SIGNAL_FUNC(reshape), NULL);
gtk_signal_connect(GTK_OBJECT(glarea), "realize",
GTK_SIGNAL_FUNC(init), NULL);
gtk_widget_set_usize(GTK_WIDGET(glarea), 450,100);
/* put glarea into window and show it all */
gtk_container_add(GTK_CONTAINER(window),GTK_WIDGET(glarea));
gtk_widget_show(GTK_WIDGET(glarea));
gtk_widget_show(GTK_WIDGET(window));
gtk_main();
return 0;
}
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