/*
 * $Header: /home/barad-dur/vision/forsyth/schenney/sced-0.94/c/RCS/zoom.c,v 1.0 1997/05/06 20:30:22 schenney Exp $
 *
 * $Log: zoom.c,v $
 * Revision 1.0  1997/05/06 20:30:22  schenney
 * Initial revision
 *
 */
#define PATCHLEVEL 0
/*
**    ScEd: A Constraint Based Scene Editor.
**    Copyright (C) 1994-1998  Stephen Chenney (schenney@cs.berkeley.edu)
**
**    This program 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.
**
**    This program 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 should have received a copy of the GNU General Public License
**    along with this program; if not, write to the Free Software
**    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/*
**  sced: A Constraint Based Object Scene Editor
**
**  zoom.c : Functions to change the screen magnification
**
**  External Functions:
**  void
**  Zoom_Dialog_Func(Widget, XtPointer, XtPointer);
**  Puts up the dialog box for changing the magnification.
*/

#include <sced.h>
#include <View.h>
#include <X11/Shell.h>
#include <X11/Xaw/Dialog.h>
#include <X11/Xaw/Text.h>
#include <X11/Xaw/AsciiText.h>
#include <X11/Xaw/Command.h>

#if HAVE_STRING_H
#include <string.h>
#elif HAVE_STRINGS_H
#include <strings.h>
#endif


/* Define the longest any valid magnification string will be. */
#define MAX_DIM_STRING_LENGTH 10


static void     Create_Zoom_Dialog();

static Widget   zoom_dialog_shell = NULL;
static Widget   zoom_dialog;
static WindowInfoPtr    current_target;
static char     magnification_string[MAX_DIM_STRING_LENGTH];


void
Zoom_Dialog_Func(Widget w, XtPointer client_data, XtPointer call_data)
{
    int     current_mag;

    if ( ! zoom_dialog_shell )
        Create_Zoom_Dialog();

    current_target = (WindowInfoPtr)client_data;

    current_mag = current_target->magnify;

    /* Set the display string. */
    sprintf(magnification_string, "%0d"HPFIX, current_mag);
    XtVaSetValues(zoom_dialog, XtNvalue, magnification_string, NULL);

    /* Set the position of the popup. */
    Position_Shell(zoom_dialog_shell, FALSE);

    XtPopup(zoom_dialog_shell, XtGrabExclusive);
}


static void
Magnification_Change_Value(WindowInfoPtr window, int new_mag)
{
    if ( new_mag < 0 )
        new_mag = -new_mag;

    window->magnify = new_mag;
    window->viewport.magnify = new_mag;
    View_Update(window, window->all_instances, CalcScreen);
    Update_Projection_Extents(window->all_instances);
}


void
Magnify_Step_Action_Func(Widget w, XEvent *e, String *s, Cardinal *c)
{
    WindowInfoPtr   window;
    int             i;

    window = WindowFromWidget(w);

    for ( i = 0 ; i < *c ; i++ )
    {
        if ( ! strcmp(s[0], "plus") )
            window->magnify *= 2.0;
        else if ( ! strcmp(s[0], "minus") )
        {
            window->magnify /= 2.0;
            if ( IsZero(window->magnify) )
                window->magnify = 0.01;
        }
    }

    Magnification_Change_Value(window, window->magnify);
}


static void
Magnification_Func(Widget w, XtPointer cl_data, XtPointer ca_data)
{
    char    *entered_string;
    double  new_mag;

    entered_string = XawDialogGetValueString(zoom_dialog);

    sscanf(entered_string, "%lf", &new_mag);

    Magnification_Change_Value(current_target, new_mag);
}


static void
Zoom_Done_Func(Widget w, XtPointer cl_data, XtPointer ca_data)
{
    XtPopdown(zoom_dialog_shell);
}

static void
Magnify_To_Fit(Widget w, XtPointer cl_data, XtPointer ca_data) 
{
    InstanceList    elmt;
    double      old_mag;
    double      new_mag;
    Dimension   view_width;
    Dimension   view_height;
    Dimension   actual_width;
    Dimension   actual_height;
    int         screen_width;
    int         screen_height;
    int         object_width;
    int         object_height;
    int         center_x, center_y;
    Boolean     changed = FALSE;

    /* Get the desired width and height of the viewport. */
    /* Use desired values because they are guaranteed to always
    ** be less than or equal to the actual values.
    ** We still want the actual dimensions to calculate the centre.
    */
    /* Also need the instances. */
    XtVaGetValues(current_target->view_widget,
                XtNdesiredWidth, &view_width,
                XtNdesiredHeight, &view_height,
                XtNwidth, &actual_width,
                XtNheight, &actual_height, NULL);
    old_mag = current_target->magnify;

    if ( current_target == &main_window && (int)view_width && (int)view_height )
    {
        screen_width = (double)view_width / 2.0;
        screen_height = (double)view_height / 2.0;
    }
    else
    {
        screen_width = (double)actual_width / 2.0;
        screen_height = (double)actual_height / 2.0;
    }
    center_x = (int)actual_width / 2;
    center_y = (int)actual_height / 2;

    /* Get the maximum absolute extremity of any object. */
#define int_abs(a) ( (a) < 0 ? -(a) : (a) )
    object_width = object_height = 1;
    for ( elmt = current_target->all_instances ; elmt ; elmt = elmt->next )
    {
        if ( ! ( elmt->the_instance->o_flags & ObjVisible ) )
            continue;

        if ( int_abs(elmt->the_instance->o_proj_extent.min.x - center_x) >
            object_width )
            object_width =
                int_abs(elmt->the_instance->o_proj_extent.min.x - center_x);
        if ( int_abs(elmt->the_instance->o_proj_extent.max.x - center_x) >
            object_width )
            object_width =
                int_abs(elmt->the_instance->o_proj_extent.max.x - center_x);
        if ( int_abs(elmt->the_instance->o_proj_extent.min.y - center_y) >
            object_height )
            object_height =
                int_abs(elmt->the_instance->o_proj_extent.min.y - center_y);
        if ( int_abs(elmt->the_instance->o_proj_extent.max.y - center_y) >
            object_height )
            object_height =
                int_abs(elmt->the_instance->o_proj_extent.max.y - center_y);

        changed = TRUE;
    }
#undef int_abs

    if ( ! changed ) return;

    new_mag = min( screen_width / (double)object_width,
                   screen_height / (double)object_height ) * old_mag;

    if ( IsZero(new_mag) )
        new_mag = 1.0;

    /* Set the display string. */
    sprintf(magnification_string, "%4.2g"HPFIX, new_mag);
    XtVaSetValues(zoom_dialog, XtNvalue, magnification_string, NULL);

    Magnification_Func(NULL, NULL, NULL);
}


/*  void
**  Create_Zoom_Dialog()
**  Creates the popup shell to change the magnification.
*/
static void
Create_Zoom_Dialog()
{
    Arg     args[5];
    int     n;


    zoom_dialog_shell = XtCreatePopupShell("Zoom",
                        transientShellWidgetClass, main_window.shell, NULL, 0);

    /* Create the dialog widget to go inside the shell. */
    n = 0;
    XtSetArg(args[n], XtNlabel, "Zoom:");   n++;
    XtSetArg(args[n], XtNvalue, "");        n++;
    zoom_dialog = XtCreateManagedWidget("zoomDialog", dialogWidgetClass,
                        zoom_dialog_shell, args, n);

    /* Add the button at the bottom of the dialog. */
    XawDialogAddButton(zoom_dialog, "Apply", Magnification_Func, NULL);
    XawDialogAddButton(zoom_dialog, "To Fit", Magnify_To_Fit, NULL);
    XawDialogAddButton(zoom_dialog, "Done", Zoom_Done_Func, NULL);

    XtOverrideTranslations(XtNameToWidget(zoom_dialog, "value"),
        XtParseTranslationTable(":<Key>Return: Zoom_Action()"));

    XtVaSetValues(XtNameToWidget(zoom_dialog, "label"),
                  XtNborderWidth, 0, NULL);

    XtRealizeWidget(zoom_dialog_shell);
}


void
Zoom_Action_Func(Widget w, XEvent *e, String *s, Cardinal *c)
{
    Magnification_Func(NULL, NULL, NULL);
    XtPopdown(zoom_dialog_shell);
}