Surface.H

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/* Copyright 2000-2018 Matt Flax <flatmax@flatmax.org>
   This file is part of GTK+ IOStream class set

   GTK+ IOStream is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   GTK+ IOStream 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 General Public License for more details.

   You have received a copy of the GNU General Public License
   along with GTK+ IOStream
 */
#ifndef SURFACE_H_
#define SURFACE_H_

#include <gtk/gtk.h>

#if GTK_MAJOR_VERSION>2 // if using GTK3 or more recent, then don't use GdkPixmaps, use cairo surfaces
#undef PIXMAP_ORIG_VER
#endif

#ifndef PIXMAP_ORIG_VER
#include <cairo/cairo.h>
#endif

#include "Widget.H"

class Surface : public Widget {
protected:
#ifdef PIXMAP_ORIG_VER
    GdkPixmap *pixmap; 
#else
    cairo_surface_t *surface; 
#endif

    static gboolean configureEventStatic(GtkWidget *widget, GdkEventConfigure *event, gpointer data) {
        //cout<<"Surface::configureEventStatic "<<endl;
        Surface *da=static_cast<Surface*>(data);
#if GTK_MAJOR_VERSION==2
        int width=widget->allocation.width, height=widget->allocation.height;
#else
        GtkAllocation widgetAlloc; // get the width and height
        gtk_widget_get_allocation(widget, &widgetAlloc);
        int width=widgetAlloc.width, height=widgetAlloc.height;
#endif
        //cout<<"Surface::configureSurface width, height "<<width<<','<<height<<endl;

#ifdef PIXMAP_ORIG_VER
        // if using a GdkPixmap, then simply paint it.
        da->setPixmap(gdk_pixmap_new(widget->window, widget->allocation.width, widget->allocation.height, -1));
        gdk_draw_rectangle(da->getPixmap(), widget->style->black_gc, TRUE, 0, 0, width, height);
#else
        // set the backing surface
        da->setSurface(cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height));
        da->clear();
        // paint the widget
        cairo_t *cr = gdk_cairo_create(gtk_widget_get_window(widget)); // create the cairo context and create the backing surface
        cairo_set_source_surface(cr, da->getSurface(), 0., 0.);
        cairo_paint(cr);
        cairo_destroy(cr);
#endif
        return da->configureEvent(event);
    }

    virtual gboolean configureEvent(GdkEventConfigure *event) {
        return false;
    }

    static gboolean exposeEventStatic(GtkWidget *widget, GdkEventExpose *event, gpointer data) {
        //cout<<"Surface::exposeSurfaceStatic"<<endl;
        Surface *da=static_cast<Surface*>(data);
#ifdef PIXMAP_ORIG_VER
        gdk_draw_drawable(gtk_widget_get_window(widget), widget->style->fg_gc[gtk_widget_get_state (widget)], da->getPixmap(), event->area.x, event->area.y, event->area.x, event->area.y,
                          event->area.width, event->area.height);
#else
        cairo_t *cr = gdk_cairo_create(gtk_widget_get_window(widget)); // create the cairo context and paint the backing surface
        cairo_set_source_surface (cr, da->getSurface(), 0, 0);
        cairo_paint(cr);
        cairo_destroy(cr);
#endif
        return da->exposeEvent();
    }

    virtual bool exposeEvent(){
        return FALSE;
    }

#ifdef PIXMAP_ORIG_VER

    void destroyPixmap(void){
        if (pixmap){
            g_object_unref(pixmap);
            pixmap=NULL;
        }
    }
#else

    void destroySurface(void){
        //cout<<"Surface::destroySurface"<<endl;
        if (surface){
            cairo_surface_destroy(surface);
            surface=NULL;
        }
    }
#endif

    void init(int width, int height){
#ifdef PIXMAP_ORIG_VER
        pixmap=NULL;
#else
        surface=NULL;
#endif
        widget=gtk_drawing_area_new ();
        show();

        g_signal_connect(G_OBJECT(widget), "expose_event", (GCallback) exposeEventStatic, this);
        g_signal_connect(G_OBJECT(widget), "configure_event", (GCallback) configureEventStatic, this);

                setSize(width, height);
    }

    void connectDamagedCallback(GCallback callback, void *data){
        g_signal_connect(G_OBJECT(widget), "damage-event", callback, this);
    }

public:

    Surface() {
        init(200, 200);
    }
    Surface(int width, int height) {
        init(width, height);
    }

    virtual ~Surface(void) {
#ifdef PIXMAP_ORIG_VER
        destroyPixmap();
#else
        destroySurface();
#endif
    }

    GtkWidget *getWidget(void){return widget;}

#ifdef PIXMAP_ORIG_VER

    GdkPixmap *getPixmap(void){return pixmap;}

    void setPixmap(GdkPixmap *pixmap_){
        destroyPixmap();
        pixmap=pixmap_;
    }
#else

    cairo_surface_t *getSurface(void){return surface;}

    void setSurface(cairo_surface_t *surface_){
        //cout<<"Surface::setSurface"<<endl;
        destroySurface();
        surface=surface_;
    }

    void clear(){
        cairo_t *cr = cairo_create(getSurface());
        cairo_set_source_rgb(cr, 0., 0., 0.); // set the background to black
        cairo_paint(cr);
        cairo_destroy(cr);
    }

#endif
};
#endif  //SURFACE_H_