kicad/3d-viewer/3d_canvas.cpp

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 1992-2016 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * 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, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

/**
 * @file 3d_canvas.cpp
*/
#include <fctsys.h>
#include <trigo.h>
#include <project.h>
#include <gestfich.h>

#include <wx/image.h>

#if !wxUSE_GLCANVAS
#error Please set wxUSE_GLCANVAS to 1 in setup.h.
#endif

#include <wx/dataobj.h>
#include <wx/clipbrd.h>
#include <wx/wupdlock.h>

#ifdef __WINDOWS__
#include <GL/glew.h>        // must be included before gl.h
#endif

#include <3d_viewer.h>
#include <3d_canvas.h>
#include <info3d_visu.h>
#include <trackball.h>
#include <3d_viewer_id.h>
#include <gl_context_mgr.h>

#include <textures/text_silk.h>
#include <textures/text_pcb.h>


static const double DELTA_MOVE_STEP = 0.7;


/*
 * EDA_3D_CANVAS implementation
 */

BEGIN_EVENT_TABLE( EDA_3D_CANVAS, wxGLCanvas )
    EVT_PAINT( EDA_3D_CANVAS::OnPaint )

    // key event:
    EVT_CHAR( EDA_3D_CANVAS::OnChar )

    // mouse events
    EVT_RIGHT_DOWN( EDA_3D_CANVAS::OnRightClick )
    EVT_MOUSEWHEEL( EDA_3D_CANVAS::OnMouseWheel )
#if wxCHECK_VERSION( 3, 1, 0 ) || defined( USE_OSX_MAGNIFY_EVENT )
    EVT_MAGNIFY( EDA_3D_CANVAS::OnMagnify )
#endif
    EVT_MOTION( EDA_3D_CANVAS::OnMouseMove )

    // other events
    EVT_ERASE_BACKGROUND( EDA_3D_CANVAS::OnEraseBackground )
    EVT_MENU_RANGE( ID_POPUP_3D_VIEW_START, ID_POPUP_3D_VIEW_END, EDA_3D_CANVAS::OnPopUpMenu )
END_EVENT_TABLE()

// Define an invalid value for some unsigned int indexes
#define INVALID_INDEX GL_INVALID_VALUE

EDA_3D_CANVAS::EDA_3D_CANVAS( EDA_3D_FRAME* parent, int* attribList ) :
    wxGLCanvas( parent, wxID_ANY, attribList, wxDefaultPosition, wxDefaultSize,
                wxFULL_REPAINT_ON_RESIZE )
{
    m_init   = false;
    m_reportWarnings = true;
    m_shadow_init = false;
    // set an invalid value to not yet initialized indexes managing
    // textures created to enhance 3D rendering
    m_text_pcb = m_text_silk = INVALID_INDEX;
    m_text_fake_shadow_front = INVALID_INDEX;
    m_text_fake_shadow_back = INVALID_INDEX;
    m_text_fake_shadow_board = INVALID_INDEX;

    // position of the front and back layers
    // (will be initialized to a better value later)
    m_ZBottom = 0.0;
    m_ZTop = 0.0;

    m_lightPos = S3D_VERTEX(0.0f, 0.0f, 30.0f);

    // Clear all gl list identifiers:
    for( int ii = GL_ID_BEGIN; ii < GL_ID_END; ii++ )
        m_glLists[ii] = 0;

    // Explicitly create a new rendering context instance for this canvas.
    m_glRC = GL_CONTEXT_MANAGER::Get().CreateCtx( this );

    DisplayStatus();
}


EDA_3D_CANVAS::~EDA_3D_CANVAS()
{
    GL_CONTEXT_MANAGER::Get().LockCtx( m_glRC, this );

    ClearLists();
    m_init = false;

    // Free the list of parsers list
    for( unsigned int i = 0; i < m_model_parsers_list.size(); i++ )
        delete m_model_parsers_list[i];

    GL_CONTEXT_MANAGER::Get().UnlockCtx( m_glRC );
    GL_CONTEXT_MANAGER::Get().DestroyCtx( m_glRC );
}


void EDA_3D_CANVAS::ClearLists( int aGlList )
{
    if( aGlList )
    {
        if( m_glLists[aGlList] > 0 )
            glDeleteLists( m_glLists[aGlList], 1 );

        m_glLists[aGlList] = 0;

        return;
    }

    for( int ii = GL_ID_BEGIN; ii < GL_ID_END; ii++ )
    {
        if( m_glLists[ii] > 0 )
            glDeleteLists( m_glLists[ii], 1 );

        m_glLists[ii] = 0;
    }

    // When m_text_fake_shadow_??? is set to INVALID_INDEX, textures are not yet created.
    if( m_text_fake_shadow_front != INVALID_INDEX )
        glDeleteTextures( 1, &m_text_fake_shadow_front );

    if( m_text_fake_shadow_back != INVALID_INDEX )
        glDeleteTextures( 1, &m_text_fake_shadow_back );

    if( m_text_fake_shadow_board != INVALID_INDEX )
        glDeleteTextures( 1, &m_text_fake_shadow_board );

    m_shadow_init = false;
}


void EDA_3D_CANVAS::OnChar( wxKeyEvent& event )
{
    SetView3D( event.GetKeyCode() );
    event.Skip();
}


void EDA_3D_CANVAS::SetView3D( int keycode )
{
    int    ii;
    double delta_move = DELTA_MOVE_STEP * GetPrm3DVisu().m_Zoom;

    switch( keycode )
    {
    case WXK_LEFT:
        m_draw3dOffset.x -= delta_move;
        break;

    case WXK_RIGHT:
        m_draw3dOffset.x += delta_move;
        break;

    case WXK_UP:
        m_draw3dOffset.y += delta_move;
        break;

    case WXK_DOWN:
        m_draw3dOffset.y -= delta_move;
        break;

    case WXK_HOME:
        GetPrm3DVisu().m_Zoom = 1.0;
        m_draw3dOffset.x = m_draw3dOffset.y = 0;
        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        break;

    case WXK_END:
        break;

    case WXK_F1:
        GetPrm3DVisu().m_Zoom /= 1.4;
        if( GetPrm3DVisu().m_Zoom <= 0.01 )
            GetPrm3DVisu().m_Zoom = 0.01;
        break;

    case WXK_F2:
        GetPrm3DVisu().m_Zoom *= 1.4;
        break;

    case '+':
        break;

    case '-':
        break;

    case 'r':
    case 'R':
        m_draw3dOffset.x = m_draw3dOffset.y = 0;
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        break;

    case 'x':
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        GetPrm3DVisu().m_ROTZ = -90;
        GetPrm3DVisu().m_ROTX = -90;
        break;

    case 'X':
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        GetPrm3DVisu().m_ROTZ = 90;
        GetPrm3DVisu().m_ROTX = -90;
        break;

    case 'y':
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        GetPrm3DVisu().m_ROTX = -90;
        break;

    case 'Y':
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        GetPrm3DVisu().m_ROTX = -90;
        GetPrm3DVisu().m_ROTZ = -180;
        break;

    case 'z':
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        break;

    case 'Z':
        for( ii = 0; ii < 4; ii++ )
            GetPrm3DVisu().m_Rot[ii] = 0.0;

        trackball( GetPrm3DVisu().m_Quat, 0.0, 0.0, 0.0, 0.0 );
        GetPrm3DVisu().m_ROTX = -180;
        break;

    default:
        return;
    }

    DisplayStatus();
    Refresh( false );
}


void EDA_3D_CANVAS::OnMouseWheel( wxMouseEvent& event )
{
    double delta = DELTA_MOVE_STEP * GetPrm3DVisu().m_Zoom;
    if ( GetPrm3DVisu().GetFlag( FL_MOUSEWHEEL_PANNING ) )
        delta *= 0.05 * event.GetWheelRotation();
    else
        if ( event.GetWheelRotation() < 0 )
            delta = -delta;

    if( GetPrm3DVisu().GetFlag( FL_MOUSEWHEEL_PANNING ) )
    {
        if( event.GetWheelAxis() == wxMOUSE_WHEEL_HORIZONTAL )
            m_draw3dOffset.x -= delta;
        else
            m_draw3dOffset.y -= delta;
    }
    else if( event.ShiftDown() )
    {
        m_draw3dOffset.y -= delta;
    }
    else if( event.ControlDown() )
    {
        m_draw3dOffset.x += delta;
    }
    else
    {
        if( event.GetWheelRotation() > 0 )
        {
            GetPrm3DVisu().m_Zoom /= 1.4;

            if( GetPrm3DVisu().m_Zoom <= 0.01 )
                GetPrm3DVisu().m_Zoom = 0.01;
        }
        else
            GetPrm3DVisu().m_Zoom *= 1.4;

    }

    DisplayStatus();
    Refresh( false );
    GetPrm3DVisu().m_Beginx = event.GetX();
    GetPrm3DVisu().m_Beginy = event.GetY();
}


#if wxCHECK_VERSION( 3, 1, 0 ) || defined( USE_OSX_MAGNIFY_EVENT )
void EDA_3D_CANVAS::OnMagnify( wxMouseEvent& event )
{
    double magnification = ( event.GetMagnification() + 1.0f );

    GetPrm3DVisu().m_Zoom /= magnification;

    if( GetPrm3DVisu().m_Zoom <= 0.01 )
    {
        GetPrm3DVisu().m_Zoom = 0.01;
    }

    DisplayStatus();
    Refresh( false );
}
#endif


void EDA_3D_CANVAS::OnMouseMove( wxMouseEvent& event )
{
    wxSize size( GetClientSize() );
    double spin_quat[4];

    if( event.Dragging() )
    {
        if( event.LeftIsDown() )
        {
            /* drag in progress, simulate trackball */
            trackball( spin_quat,
                       (2.0 * GetPrm3DVisu().m_Beginx - size.x) / size.x,
                       (size.y - 2.0 * GetPrm3DVisu().m_Beginy) / size.y,
                       (     2.0 * event.GetX() - size.x) / size.x,
                       ( size.y - 2.0 * event.GetY() ) / size.y );

            add_quats( spin_quat, GetPrm3DVisu().m_Quat, GetPrm3DVisu().m_Quat );
        }
        else if( event.MiddleIsDown() )
        {
            /* middle button drag -> pan */

            /* Current zoom and an additional factor are taken into account
             * for the amount of panning. */
            const double PAN_FACTOR = 8.0 * GetPrm3DVisu().m_Zoom;
            m_draw3dOffset.x -= PAN_FACTOR *
                           ( GetPrm3DVisu().m_Beginx - event.GetX() ) / size.x;
            m_draw3dOffset.y -= PAN_FACTOR *
                           (event.GetY() - GetPrm3DVisu().m_Beginy) / size.y;
        }

        /* orientation has changed, redraw mesh */
        DisplayStatus();
        Refresh( false );
    }

    GetPrm3DVisu().m_Beginx = event.GetX();
    GetPrm3DVisu().m_Beginy = event.GetY();
}


void EDA_3D_CANVAS::OnRightClick( wxMouseEvent& event )
{
    wxPoint     pos;
    wxMenu      PopUpMenu;

    pos.x = event.GetX();
    pos.y = event.GetY();

    wxMenuItem* item = new wxMenuItem( &PopUpMenu, ID_POPUP_ZOOMIN, _( "Zoom +" ) );
    item->SetBitmap( KiBitmap( zoom_in_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_ZOOMOUT, _( "Zoom -" ) );
    item->SetBitmap( KiBitmap( zoom_out_xpm ));
    PopUpMenu.Append( item );

    PopUpMenu.AppendSeparator();
    item = new wxMenuItem( &PopUpMenu, ID_POPUP_VIEW_ZPOS, _( "Top View" ) );
    item->SetBitmap( KiBitmap( axis3d_top_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_VIEW_ZNEG, _( "Bottom View" ) );
    item->SetBitmap( KiBitmap( axis3d_bottom_xpm ));
    PopUpMenu.Append( item );

    PopUpMenu.AppendSeparator();
    item = new wxMenuItem( &PopUpMenu, ID_POPUP_VIEW_XPOS, _( "Right View" ) );
    item->SetBitmap( KiBitmap( axis3d_right_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_VIEW_XNEG, _( "Left View" ) );
    item->SetBitmap( KiBitmap( axis3d_left_xpm ));
    PopUpMenu.Append( item );

    PopUpMenu.AppendSeparator();
    item = new wxMenuItem( &PopUpMenu, ID_POPUP_VIEW_YPOS, _( "Front View" ) );
    item->SetBitmap( KiBitmap( axis3d_front_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_VIEW_YNEG, _( "Back View" ) );
    item->SetBitmap( KiBitmap( axis3d_back_xpm ));
    PopUpMenu.Append( item );

    PopUpMenu.AppendSeparator();
    item = new wxMenuItem( &PopUpMenu, ID_POPUP_MOVE3D_LEFT, _( "Move left <-" ) );
    item->SetBitmap( KiBitmap( left_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_MOVE3D_RIGHT, _( "Move right ->" ) );
    item->SetBitmap( KiBitmap( right_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_MOVE3D_UP, _( "Move Up ^" ) );
    item->SetBitmap( KiBitmap( up_xpm ));
    PopUpMenu.Append( item );

    item = new wxMenuItem( &PopUpMenu, ID_POPUP_MOVE3D_DOWN, _( "Move Down" ) );
    item->SetBitmap( KiBitmap( down_xpm ));
    PopUpMenu.Append( item );

    PopupMenu( &PopUpMenu, pos );
}


void EDA_3D_CANVAS::OnPopUpMenu( wxCommandEvent& event )
{
    int key = 0;

    switch( event.GetId() )
    {
    case ID_POPUP_ZOOMIN:
        key = WXK_F1;
        break;

    case ID_POPUP_ZOOMOUT:
        key = WXK_F2;
        break;

    case ID_POPUP_VIEW_XPOS:
        key = 'x';
        break;

    case ID_POPUP_VIEW_XNEG:
        key = 'X';
        break;

    case ID_POPUP_VIEW_YPOS:
        key = 'y';
        break;

    case ID_POPUP_VIEW_YNEG:
        key = 'Y';
        break;

    case ID_POPUP_VIEW_ZPOS:
        key = 'z';
        break;

    case ID_POPUP_VIEW_ZNEG:
        key = 'Z';
        break;

    case ID_POPUP_MOVE3D_LEFT:
        key = WXK_LEFT;
        break;

    case ID_POPUP_MOVE3D_RIGHT:
        key = WXK_RIGHT;
        break;

    case ID_POPUP_MOVE3D_UP:
        key = WXK_UP;
        break;

    case ID_POPUP_MOVE3D_DOWN:
        key = WXK_DOWN;
        break;

    default:
        return;
    }

    SetView3D( key );
}


void EDA_3D_CANVAS::DisplayStatus()
{
    wxString msg;

    msg.Printf( wxT( "dx %3.2f" ), m_draw3dOffset.x );
    Parent()->SetStatusText( msg, 1 );

    msg.Printf( wxT( "dy %3.2f" ), m_draw3dOffset.y );
    Parent()->SetStatusText( msg, 2 );

    msg.Printf( _( "Zoom: %3.1f" ), 45 * GetPrm3DVisu().m_Zoom );
    Parent()->SetStatusText( msg, 3 );
}


void EDA_3D_CANVAS::OnPaint( wxPaintEvent& event )
{
    wxPaintDC dc( this );

    Redraw();
    event.Skip();
}


void EDA_3D_CANVAS::OnEraseBackground( wxEraseEvent& event )
{
    // Do nothing, to avoid flashing.
}

typedef struct s_sImage
{
  unsigned int   width;
  unsigned int   height;
  unsigned int   bytes_per_pixel; /* 2:RGB16, 3:RGB, 4:RGBA */
  unsigned char  pixel_data[64 * 64 * 4 + 1];
}tsImage;


GLuint load_and_generate_texture( tsImage *image )
{

    GLuint texture;
    glPixelStorei (GL_UNPACK_ALIGNMENT, 1);
    glPixelStorei (GL_PACK_ALIGNMENT, 1);

    glGenTextures( 1, &texture );
    glBindTexture( GL_TEXTURE_2D, texture );
    gluBuild2DMipmaps( GL_TEXTURE_2D, GL_RGBA, image->width, image->height,
                       GL_RGBA, GL_UNSIGNED_BYTE, image->pixel_data );

    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR );
    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

    glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
    return texture;
}


void EDA_3D_CANVAS::InitGL()
{
    if( !m_init )
    {
        m_init = true;


        m_text_pcb = load_and_generate_texture( (tsImage *)&text_pcb  );
        m_text_silk = load_and_generate_texture( (tsImage *)&text_silk );

        GetPrm3DVisu().m_Zoom = 1.0;
        m_ZBottom = 1.0;
        m_ZTop = 10.0;

        glDisable( GL_CULL_FACE );      // show back faces
        glEnable( GL_DEPTH_TEST );      // Enable z-buffering
        glEnable( GL_ALPHA_TEST );
        glEnable( GL_LINE_SMOOTH );
//        glEnable(GL_POLYGON_SMOOTH);  // creates issues with some graphic cards
        glEnable( GL_NORMALIZE );
        glEnable( GL_COLOR_MATERIAL );
        glColorMaterial( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE );

        // speedups
        //glEnable( GL_DITHER );
        glHint( GL_PERSPECTIVE_CORRECTION_HINT, GL_DONT_CARE );
        glHint( GL_LINE_SMOOTH_HINT, GL_NICEST );
        glHint( GL_POLYGON_SMOOTH_HINT, GL_NICEST );

        // Initialize alpha blending function.
        glEnable( GL_BLEND );
        glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
    }
}


void EDA_3D_CANVAS::SetLights()
{
    // activate light. the source is above the xy plane, at source_pos
    GLfloat source_pos[4]    = { m_lightPos.x, m_lightPos.y, m_lightPos.z, 0.0f };
    GLfloat light_color[4];     // color of lights (RGBA values)
    light_color[3] = 1.0;

    // Light above the xy plane
    light_color[0] = light_color[1] = light_color[2] = 0.0;
    glLightfv( GL_LIGHT0, GL_AMBIENT, light_color );

    light_color[0] = light_color[1] = light_color[2] = 1.0;
    glLightfv( GL_LIGHT0, GL_DIFFUSE, light_color );

    light_color[0] = light_color[1] = light_color[2] = 1.0;
    glLightfv( GL_LIGHT0, GL_SPECULAR, light_color );

    glLightfv( GL_LIGHT0, GL_POSITION, source_pos );

    light_color[0] = light_color[1] = light_color[2] = 0.2;
    glLightModelfv( GL_LIGHT_MODEL_AMBIENT, light_color );

    glLightModeli( GL_LIGHT_MODEL_TWO_SIDE, GL_FALSE );

    glEnable( GL_LIGHT0 );      // White spot on Z axis ( top )
    glEnable( GL_LIGHTING );
}


void EDA_3D_CANVAS::TakeScreenshot( wxCommandEvent& event )
{
    static wxFileName fn;                 // Remember path between saves during this session only.
    wxString          FullFileName;
    wxString          file_ext, mask;
    bool              fmt_is_jpeg = false;

    // First time path is set to the project path.
    if( !fn.IsOk() )
        fn = Parent()->Prj().GetProjectFullName();

    if( event.GetId() == ID_MENU_SCREENCOPY_JPEG )
        fmt_is_jpeg = true;

    if( event.GetId() != ID_TOOL_SCREENCOPY_TOCLIBBOARD )
    {
        file_ext     = fmt_is_jpeg ? wxT( "jpg" ) : wxT( "png" );
        mask         = wxT( "*." ) + file_ext;
        fn.SetExt( file_ext );

        FullFileName = EDA_FILE_SELECTOR( _( "3D Image File Name:" ), fn.GetPath(),
                                          fn.GetFullName(), file_ext, mask, this,
                                          wxFD_SAVE | wxFD_OVERWRITE_PROMPT, true );

        if( FullFileName.IsEmpty() )
            return;

        fn = FullFileName;

        // Be sure the screen area destroyed by the file dialog is redrawn before making
        // a screen copy.
        // Without this call, under Linux the screen refresh is made to late.
        wxYield();
    }

    struct viewport_params
    {
        GLint originx;
        GLint originy;
        GLint x;
        GLint y;
    } viewport;

    // Be sure we have the latest 3D view (remember 3D view is buffered)
    Refresh();
    wxYield();

    // Build image from the 3D buffer
    wxWindowUpdateLocker noUpdates( this );
    glGetIntegerv( GL_VIEWPORT, (GLint*) &viewport );

    unsigned char*       pixelbuffer = (unsigned char*) malloc( viewport.x * viewport.y * 3 );
    unsigned char*       alphabuffer = (unsigned char*) malloc( viewport.x * viewport.y );
    wxImage image_3d( viewport.x, viewport.y );

    glPixelStorei( GL_PACK_ALIGNMENT, 1 );
    glReadBuffer( GL_BACK_LEFT );
    glReadPixels( viewport.originx, viewport.originy,
                  viewport.x, viewport.y,
                  GL_RGB, GL_UNSIGNED_BYTE, pixelbuffer );
    glReadPixels( viewport.originx, viewport.originy,
                  viewport.x, viewport.y,
                  GL_ALPHA, GL_UNSIGNED_BYTE, alphabuffer );

    image_3d.SetData( pixelbuffer );
    image_3d.SetAlpha( alphabuffer );
    image_3d = image_3d.Mirror( false );
    wxBitmap bitmap( image_3d );

    if( event.GetId() == ID_TOOL_SCREENCOPY_TOCLIBBOARD )
    {
        if( wxTheClipboard->Open() )
        {
            wxBitmapDataObject* dobjBmp = new wxBitmapDataObject( bitmap );

            if( !wxTheClipboard->SetData( dobjBmp ) )
                wxMessageBox( _( "Failed to copy image to clipboard" ) );

            wxTheClipboard->Flush();    /* the data in clipboard will stay
                                         * available after the application exits */
            wxTheClipboard->Close();
        }
    }
    else
    {
        wxImage image = bitmap.ConvertToImage();

        if( !image.SaveFile( FullFileName,
                             fmt_is_jpeg ? wxBITMAP_TYPE_JPEG : wxBITMAP_TYPE_PNG ) )
            wxMessageBox( _( "Can't save file" ) );

        image.Destroy();
    }
}