OpenGL seems to operate using physical pixels, so we need to factor in the scale factor when setting the GL viewport. Closes #17391. Closes https://github.com/wxWidgets/wxWidgets/pull/1470
		
			
				
	
	
		
			516 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			516 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| ///////////////////////////////////////////////////////////////////////////////
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| // Name:        cube.cpp
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| // Purpose:     wxGLCanvas demo program
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| // Author:      Julian Smart
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| // Modified by: Vadim Zeitlin to use new wxGLCanvas API (2007-04-09)
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| // Created:     04/01/98
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| // Copyright:   (c) Julian Smart
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| // Licence:     wxWindows licence
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| ///////////////////////////////////////////////////////////////////////////////
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| 
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| // ============================================================================
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| // declarations
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| // ============================================================================
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| 
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| // ----------------------------------------------------------------------------
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| // headers
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| // ----------------------------------------------------------------------------
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| 
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| // For compilers that support precompilation, includes "wx.h".
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| #include "wx/wxprec.h"
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| 
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| #ifdef __BORLANDC__
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| #pragma hdrstop
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| #endif
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| 
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| #ifndef WX_PRECOMP
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| #include "wx/wx.h"
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| #endif
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| 
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| #if !wxUSE_GLCANVAS
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|     #error "OpenGL required: set wxUSE_GLCANVAS to 1 and rebuild the library"
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| #endif
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| 
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| #include "cube.h"
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| 
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| #ifndef wxHAS_IMAGES_IN_RESOURCES
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|     #include "../../sample.xpm"
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| #endif
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| 
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| // ----------------------------------------------------------------------------
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| // constants
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| // ----------------------------------------------------------------------------
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| 
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| // control ids
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| enum
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| {
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|     SpinTimer = wxID_HIGHEST + 1
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| };
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| 
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| // ----------------------------------------------------------------------------
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| // helper functions
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| // ----------------------------------------------------------------------------
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| 
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| static void CheckGLError()
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| {
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|     GLenum errLast = GL_NO_ERROR;
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| 
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|     for ( ;; )
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|     {
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|         GLenum err = glGetError();
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|         if ( err == GL_NO_ERROR )
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|             return;
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| 
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|         // normally the error is reset by the call to glGetError() but if
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|         // glGetError() itself returns an error, we risk looping forever here
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|         // so check that we get a different error than the last time
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|         if ( err == errLast )
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|         {
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|             wxLogError("OpenGL error state couldn't be reset.");
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|             return;
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|         }
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| 
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|         errLast = err;
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| 
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|         wxLogError("OpenGL error %d", err);
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|     }
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| }
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| 
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| // function to draw the texture for cube faces
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| static wxImage DrawDice(int size, unsigned num)
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| {
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|     wxASSERT_MSG( num >= 1 && num <= 6, "invalid dice index" );
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| 
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|     const int dot = size/16;        // radius of a single dot
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|     const int gap = 5*size/32;      // gap between dots
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| 
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|     wxBitmap bmp(size, size);
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|     wxMemoryDC dc;
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|     dc.SelectObject(bmp);
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|     dc.SetBackground(*wxWHITE_BRUSH);
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|     dc.Clear();
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|     dc.SetBrush(*wxBLACK_BRUSH);
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| 
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|     // the upper left and lower right points
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|     if ( num != 1 )
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|     {
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|         dc.DrawCircle(gap + dot, gap + dot, dot);
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|         dc.DrawCircle(size - gap - dot, size - gap - dot, dot);
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|     }
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| 
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|     // draw the central point for odd dices
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|     if ( num % 2 )
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|     {
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|         dc.DrawCircle(size/2, size/2, dot);
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|     }
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| 
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|     // the upper right and lower left points
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|     if ( num > 3 )
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|     {
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|         dc.DrawCircle(size - gap - dot, gap + dot, dot);
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|         dc.DrawCircle(gap + dot, size - gap - dot, dot);
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|     }
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| 
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|     // finally those 2 are only for the last dice
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|     if ( num == 6 )
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|     {
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|         dc.DrawCircle(gap + dot, size/2, dot);
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|         dc.DrawCircle(size - gap - dot, size/2, dot);
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|     }
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| 
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|     dc.SelectObject(wxNullBitmap);
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| 
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|     return bmp.ConvertToImage();
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| }
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| 
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| // ============================================================================
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| // implementation
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| // ============================================================================
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| 
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| // ----------------------------------------------------------------------------
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| // TestGLContext
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| // ----------------------------------------------------------------------------
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| 
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| TestGLContext::TestGLContext(wxGLCanvas *canvas)
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|              : wxGLContext(canvas)
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| {
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|     SetCurrent(*canvas);
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| 
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|     // set up the parameters we want to use
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|     glEnable(GL_CULL_FACE);
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|     glEnable(GL_DEPTH_TEST);
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|     glEnable(GL_LIGHTING);
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|     glEnable(GL_LIGHT0);
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|     glEnable(GL_TEXTURE_2D);
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| 
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|     // add slightly more light, the default lighting is rather dark
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|     GLfloat ambient[] = { 0.5, 0.5, 0.5, 0.5 };
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|     glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
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| 
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|     // set viewing projection
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|     glMatrixMode(GL_PROJECTION);
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|     glLoadIdentity();
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|     glFrustum(-0.5f, 0.5f, -0.5f, 0.5f, 1.0f, 3.0f);
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| 
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|     // create the textures to use for cube sides: they will be reused by all
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|     // canvases (which is probably not critical in the case of simple textures
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|     // we use here but could be really important for a real application where
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|     // each texture could take many megabytes)
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|     glGenTextures(WXSIZEOF(m_textures), m_textures);
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| 
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|     for ( unsigned i = 0; i < WXSIZEOF(m_textures); i++ )
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|     {
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|         glBindTexture(GL_TEXTURE_2D, m_textures[i]);
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| 
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|         glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
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|         glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
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|         glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
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|         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
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|         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
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| 
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|         const wxImage img(DrawDice(256, i + 1));
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| 
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|         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
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|         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img.GetWidth(), img.GetHeight(),
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|                      0, GL_RGB, GL_UNSIGNED_BYTE, img.GetData());
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|     }
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| 
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|     CheckGLError();
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| }
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| 
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| void TestGLContext::DrawRotatedCube(float xangle, float yangle)
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| {
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|     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
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| 
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|     glMatrixMode(GL_MODELVIEW);
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|     glLoadIdentity();
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|     glTranslatef(0.0f, 0.0f, -2.0f);
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|     glRotatef(xangle, 1.0f, 0.0f, 0.0f);
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|     glRotatef(yangle, 0.0f, 1.0f, 0.0f);
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| 
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|     // draw six faces of a cube of size 1 centered at (0, 0, 0)
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|     glBindTexture(GL_TEXTURE_2D, m_textures[0]);
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|     glBegin(GL_QUADS);
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|         glNormal3f( 0.0f, 0.0f, 1.0f);
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|         glTexCoord2f(0, 0); glVertex3f( 0.5f, 0.5f, 0.5f);
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|         glTexCoord2f(1, 0); glVertex3f(-0.5f, 0.5f, 0.5f);
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|         glTexCoord2f(1, 1); glVertex3f(-0.5f,-0.5f, 0.5f);
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|         glTexCoord2f(0, 1); glVertex3f( 0.5f,-0.5f, 0.5f);
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|     glEnd();
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| 
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|     glBindTexture(GL_TEXTURE_2D, m_textures[1]);
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|     glBegin(GL_QUADS);
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|         glNormal3f( 0.0f, 0.0f,-1.0f);
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|         glTexCoord2f(0, 0); glVertex3f(-0.5f,-0.5f,-0.5f);
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|         glTexCoord2f(1, 0); glVertex3f(-0.5f, 0.5f,-0.5f);
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|         glTexCoord2f(1, 1); glVertex3f( 0.5f, 0.5f,-0.5f);
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|         glTexCoord2f(0, 1); glVertex3f( 0.5f,-0.5f,-0.5f);
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|     glEnd();
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| 
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|     glBindTexture(GL_TEXTURE_2D, m_textures[2]);
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|     glBegin(GL_QUADS);
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|         glNormal3f( 0.0f, 1.0f, 0.0f);
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|         glTexCoord2f(0, 0); glVertex3f( 0.5f, 0.5f, 0.5f);
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|         glTexCoord2f(1, 0); glVertex3f( 0.5f, 0.5f,-0.5f);
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|         glTexCoord2f(1, 1); glVertex3f(-0.5f, 0.5f,-0.5f);
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|         glTexCoord2f(0, 1); glVertex3f(-0.5f, 0.5f, 0.5f);
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|     glEnd();
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| 
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|     glBindTexture(GL_TEXTURE_2D, m_textures[3]);
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|     glBegin(GL_QUADS);
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|         glNormal3f( 0.0f,-1.0f, 0.0f);
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|         glTexCoord2f(0, 0); glVertex3f(-0.5f,-0.5f,-0.5f);
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|         glTexCoord2f(1, 0); glVertex3f( 0.5f,-0.5f,-0.5f);
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|         glTexCoord2f(1, 1); glVertex3f( 0.5f,-0.5f, 0.5f);
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|         glTexCoord2f(0, 1); glVertex3f(-0.5f,-0.5f, 0.5f);
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|     glEnd();
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| 
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|     glBindTexture(GL_TEXTURE_2D, m_textures[4]);
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|     glBegin(GL_QUADS);
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|         glNormal3f( 1.0f, 0.0f, 0.0f);
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|         glTexCoord2f(0, 0); glVertex3f( 0.5f, 0.5f, 0.5f);
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|         glTexCoord2f(1, 0); glVertex3f( 0.5f,-0.5f, 0.5f);
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|         glTexCoord2f(1, 1); glVertex3f( 0.5f,-0.5f,-0.5f);
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|         glTexCoord2f(0, 1); glVertex3f( 0.5f, 0.5f,-0.5f);
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|     glEnd();
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| 
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|     glBindTexture(GL_TEXTURE_2D, m_textures[5]);
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|     glBegin(GL_QUADS);
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|         glNormal3f(-1.0f, 0.0f, 0.0f);
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|         glTexCoord2f(0, 0); glVertex3f(-0.5f,-0.5f,-0.5f);
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|         glTexCoord2f(1, 0); glVertex3f(-0.5f,-0.5f, 0.5f);
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|         glTexCoord2f(1, 1); glVertex3f(-0.5f, 0.5f, 0.5f);
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|         glTexCoord2f(0, 1); glVertex3f(-0.5f, 0.5f,-0.5f);
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|     glEnd();
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| 
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|     glFlush();
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| 
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|     CheckGLError();
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| }
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| 
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| 
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| // ----------------------------------------------------------------------------
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| // MyApp: the application object
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| // ----------------------------------------------------------------------------
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| 
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| wxIMPLEMENT_APP(MyApp);
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| 
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| bool MyApp::OnInit()
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| {
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|     if ( !wxApp::OnInit() )
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|         return false;
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| 
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|     new MyFrame();
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| 
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|     return true;
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| }
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| 
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| int MyApp::OnExit()
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| {
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|     delete m_glContext;
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|     delete m_glStereoContext;
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| 
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|     return wxApp::OnExit();
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| }
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| 
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| TestGLContext& MyApp::GetContext(wxGLCanvas *canvas, bool useStereo)
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| {
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|     TestGLContext *glContext;
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|     if ( useStereo )
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|     {
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|         if ( !m_glStereoContext )
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|         {
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|             // Create the OpenGL context for the first stereo window which needs it:
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|             // subsequently created windows will all share the same context.
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|             m_glStereoContext = new TestGLContext(canvas);
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|         }
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|         glContext = m_glStereoContext;
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|     }
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|     else
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|     {
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|         if ( !m_glContext )
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|         {
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|             // Create the OpenGL context for the first mono window which needs it:
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|             // subsequently created windows will all share the same context.
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|             m_glContext = new TestGLContext(canvas);
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|         }
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|         glContext = m_glContext;
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|     }
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| 
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|     glContext->SetCurrent(*canvas);
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| 
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|     return *glContext;
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| }
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| 
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| // ----------------------------------------------------------------------------
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| // TestGLCanvas
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| // ----------------------------------------------------------------------------
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| 
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| wxBEGIN_EVENT_TABLE(TestGLCanvas, wxGLCanvas)
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|     EVT_PAINT(TestGLCanvas::OnPaint)
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|     EVT_KEY_DOWN(TestGLCanvas::OnKeyDown)
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|     EVT_TIMER(SpinTimer, TestGLCanvas::OnSpinTimer)
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| wxEND_EVENT_TABLE()
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| 
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| TestGLCanvas::TestGLCanvas(wxWindow *parent, int *attribList)
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|     // With perspective OpenGL graphics, the wxFULL_REPAINT_ON_RESIZE style
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|     // flag should always be set, because even making the canvas smaller should
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|     // be followed by a paint event that updates the entire canvas with new
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|     // viewport settings.
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|     : wxGLCanvas(parent, wxID_ANY, attribList,
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|                  wxDefaultPosition, wxDefaultSize,
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|                  wxFULL_REPAINT_ON_RESIZE),
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|       m_xangle(30.0),
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|       m_yangle(30.0),
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|       m_spinTimer(this,SpinTimer),
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|       m_useStereo(false),
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|       m_stereoWarningAlreadyDisplayed(false)
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| {
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|     if ( attribList )
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|     {
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|         int i = 0;
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|         while ( attribList[i] != 0 )
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|         {
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|             if ( attribList[i] == WX_GL_STEREO )
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|                 m_useStereo = true;
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|             ++i;
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|         }
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|     }
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| }
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| 
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| void TestGLCanvas::OnPaint(wxPaintEvent& WXUNUSED(event))
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| {
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|     // This is required even though dc is not used otherwise.
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|     wxPaintDC dc(this);
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| 
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|     // Set the OpenGL viewport according to the client size of this canvas.
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|     // This is done here rather than in a wxSizeEvent handler because our
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|     // OpenGL rendering context (and thus viewport setting) is used with
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|     // multiple canvases: If we updated the viewport in the wxSizeEvent
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|     // handler, changing the size of one canvas causes a viewport setting that
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|     // is wrong when next another canvas is repainted.
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|     const wxSize ClientSize = GetClientSize() * GetContentScaleFactor();
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| 
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|     TestGLContext& canvas = wxGetApp().GetContext(this, m_useStereo);
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|     glViewport(0, 0, ClientSize.x, ClientSize.y);
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| 
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|     // Render the graphics and swap the buffers.
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|     GLboolean quadStereoSupported;
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|     glGetBooleanv( GL_STEREO, &quadStereoSupported);
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|     if ( quadStereoSupported )
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|     {
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|         glDrawBuffer( GL_BACK_LEFT );
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|         glMatrixMode(GL_PROJECTION);
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|         glLoadIdentity();
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|         glFrustum(-0.47f, 0.53f, -0.5f, 0.5f, 1.0f, 3.0f);
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|         canvas.DrawRotatedCube(m_xangle, m_yangle);
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|         CheckGLError();
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|         glDrawBuffer( GL_BACK_RIGHT );
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|         glMatrixMode(GL_PROJECTION);
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|         glLoadIdentity();
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|         glFrustum(-0.53f, 0.47f, -0.5f, 0.5f, 1.0f, 3.0f);
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|         canvas.DrawRotatedCube(m_xangle, m_yangle);
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|         CheckGLError();
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|     }
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|     else
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|     {
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|         canvas.DrawRotatedCube(m_xangle, m_yangle);
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|         if ( m_useStereo && !m_stereoWarningAlreadyDisplayed )
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|         {
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|             m_stereoWarningAlreadyDisplayed = true;
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|             wxLogError("Stereo not supported by the graphics card.");
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|         }
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|     }
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|     SwapBuffers();
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| }
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| 
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| void TestGLCanvas::Spin(float xSpin, float ySpin)
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| {
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|     m_xangle += xSpin;
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|     m_yangle += ySpin;
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| 
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|     Refresh(false);
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| }
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| 
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| void TestGLCanvas::OnKeyDown(wxKeyEvent& event)
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| {
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|     float angle = 5.0;
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| 
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|     switch ( event.GetKeyCode() )
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|     {
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|         case WXK_RIGHT:
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|             Spin( 0.0, -angle );
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|             break;
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| 
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|         case WXK_LEFT:
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|             Spin( 0.0, angle );
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|             break;
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| 
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|         case WXK_DOWN:
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|             Spin( -angle, 0.0 );
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|             break;
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| 
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|         case WXK_UP:
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|             Spin( angle, 0.0 );
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|             break;
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| 
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|         case WXK_SPACE:
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|             if ( m_spinTimer.IsRunning() )
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|                 m_spinTimer.Stop();
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|             else
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|                 m_spinTimer.Start( 25 );
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|             break;
 | |
| 
 | |
|         default:
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|             event.Skip();
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|             return;
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|     }
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| }
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| 
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| void TestGLCanvas::OnSpinTimer(wxTimerEvent& WXUNUSED(event))
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| {
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|     Spin(0.0, 4.0);
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| }
 | |
| 
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| wxString glGetwxString(GLenum name)
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| {
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|     const GLubyte *v = glGetString(name);
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|     if ( v == 0 )
 | |
|     {
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|         // The error is not important. It is GL_INVALID_ENUM.
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|         // We just want to clear the error stack.
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|         glGetError();
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| 
 | |
|         return wxString();
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|     }
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| 
 | |
|     return wxString((const char*)v);
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| }
 | |
| 
 | |
| 
 | |
| // ----------------------------------------------------------------------------
 | |
| // MyFrame: main application window
 | |
| // ----------------------------------------------------------------------------
 | |
| 
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| wxBEGIN_EVENT_TABLE(MyFrame, wxFrame)
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|     EVT_MENU(wxID_NEW, MyFrame::OnNewWindow)
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|     EVT_MENU(NEW_STEREO_WINDOW, MyFrame::OnNewStereoWindow)
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|     EVT_MENU(wxID_CLOSE, MyFrame::OnClose)
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| wxEND_EVENT_TABLE()
 | |
| 
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| MyFrame::MyFrame( bool stereoWindow )
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|        : wxFrame(NULL, wxID_ANY, "wxWidgets OpenGL Cube Sample")
 | |
| {
 | |
|     int stereoAttribList[] = { WX_GL_RGBA, WX_GL_DOUBLEBUFFER, WX_GL_STEREO, 0 };
 | |
| 
 | |
|     new TestGLCanvas(this, stereoWindow ? stereoAttribList : NULL);
 | |
| 
 | |
|     SetIcon(wxICON(sample));
 | |
| 
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|     // Make a menubar
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|     wxMenu *menu = new wxMenu;
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|     menu->Append(wxID_NEW);
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|     menu->Append(NEW_STEREO_WINDOW, "New Stereo Window");
 | |
|     menu->AppendSeparator();
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|     menu->Append(wxID_CLOSE);
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|     wxMenuBar *menuBar = new wxMenuBar;
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|     menuBar->Append(menu, "&Cube");
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| 
 | |
|     SetMenuBar(menuBar);
 | |
| 
 | |
|     CreateStatusBar();
 | |
| 
 | |
|     SetClientSize(400, 400);
 | |
|     Show();
 | |
| 
 | |
|     // test IsDisplaySupported() function:
 | |
|     static const int attribs[] = { WX_GL_RGBA, WX_GL_DOUBLEBUFFER, 0 };
 | |
|     wxLogStatus("Double-buffered display %s supported",
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|                 wxGLCanvas::IsDisplaySupported(attribs) ? "is" : "not");
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| 
 | |
|     if ( stereoWindow )
 | |
|     {
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|         const wxString vendor = glGetwxString(GL_VENDOR).Lower();
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|         const wxString renderer = glGetwxString(GL_RENDERER).Lower();
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|         if ( vendor.find("nvidia") != wxString::npos &&
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|                 renderer.find("quadro") == wxString::npos )
 | |
|             ShowFullScreen(true);
 | |
|     }
 | |
| }
 | |
| 
 | |
| void MyFrame::OnClose(wxCommandEvent& WXUNUSED(event))
 | |
| {
 | |
|     // true is to force the frame to close
 | |
|     Close(true);
 | |
| }
 | |
| 
 | |
| void MyFrame::OnNewWindow( wxCommandEvent& WXUNUSED(event) )
 | |
| {
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|     new MyFrame();
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| }
 | |
| 
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| void MyFrame::OnNewStereoWindow( wxCommandEvent& WXUNUSED(event) )
 | |
| {
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|     new MyFrame(true);
 | |
| }
 |