]> git.saurik.com Git - wxWidgets.git/blobdiff - samples/opengl/cube/cube.cpp
Removed dummy wxFont == operator implementation (IIRC was needed to compile with...
[wxWidgets.git] / samples / opengl / cube / cube.cpp
index b3bcb9f699603308faee12ab29b5021d1e6486dd..74cd1bf7ebf194a3877541138eaa2ad75130fc01 100644 (file)
     #include "../../sample.xpm"
 #endif
 
-// ============================================================================
-// implementation
-// ============================================================================
-
 // ----------------------------------------------------------------------------
-// MyApp: the application object
+// helper functions
 // ----------------------------------------------------------------------------
 
-IMPLEMENT_APP(MyApp)
-
-bool MyApp::OnInit()
+static void CheckGLError()
 {
-    if ( !wxApp::OnInit() )
-        return false;
+    GLenum errLast = GL_NO_ERROR;
 
-    // Create the main window
-    new MyFrame();
+    for ( ;; )
+    {
+        GLenum err = glGetError();
+        if ( err == GL_NO_ERROR )
+            return;
 
-    return true;
-}
+        // normally the error is reset by the call to glGetError() but if
+        // glGetError() itself returns an error, we risk looping forever here
+        // so check that we get a different error than the last time
+        if ( err == errLast )
+        {
+            wxLogError(_T("OpenGL error state couldn't be reset."));
+            return;
+        }
 
-int MyApp::OnExit()
-{
-    delete m_glContext;
+        errLast = err;
 
-    return wxApp::OnExit();
+        wxLogError(_T("OpenGL error %d"), err);
+    }
 }
 
-TestGLContext& MyApp::GetContext(wxGLCanvas *canvas)
+// function to draw the texture for cube faces
+static wxImage DrawDice(int size, unsigned num)
 {
-    if ( !m_glContext )
-        m_glContext = new TestGLContext(canvas);
+    wxASSERT_MSG( num >= 1 && num <= 6, _T("invalid dice index") );
 
-    m_glContext->SetCurrent(*canvas);
+    const int dot = size/16;        // radius of a single dot
+    const int gap = 5*size/32;      // gap between dots
 
-    return *m_glContext;
+    wxBitmap bmp(size, size);
+    wxMemoryDC dc;
+    dc.SelectObject(bmp);
+    dc.SetBackground(*wxWHITE_BRUSH);
+    dc.Clear();
+    dc.SetBrush(*wxBLACK_BRUSH);
+
+    // the upper left and lower right points
+    if ( num != 1 )
+    {
+        dc.DrawCircle(gap + dot, gap + dot, dot);
+        dc.DrawCircle(size - gap - dot, size - gap - dot, dot);
+    }
+
+    // draw the central point for odd dices
+    if ( num % 2 )
+    {
+        dc.DrawCircle(size/2, size/2, dot);
+    }
+
+    // the upper right and lower left points
+    if ( num > 3 )
+    {
+        dc.DrawCircle(size - gap - dot, gap + dot, dot);
+        dc.DrawCircle(gap + dot, size - gap - dot, dot);
+    }
+
+    // finally those 2 are only for the last dice
+    if ( num == 6 )
+    {
+        dc.DrawCircle(gap + dot, size/2, dot);
+        dc.DrawCircle(size - gap - dot, size/2, dot);
+    }
+
+    dc.SelectObject(wxNullBitmap);
+
+    return bmp.ConvertToImage();
 }
 
+// ============================================================================
+// implementation
+// ============================================================================
+
 // ----------------------------------------------------------------------------
 // TestGLContext
 // ----------------------------------------------------------------------------
@@ -83,62 +125,51 @@ TestGLContext& MyApp::GetContext(wxGLCanvas *canvas)
 TestGLContext::TestGLContext(wxGLCanvas *canvas)
              : wxGLContext(canvas)
 {
-    m_gllist = 0;
-}
-
-void TestGLContext::Init()
-{
-    if ( m_gllist )
-        return;
-
-    /* set viewing projection */
-    glMatrixMode(GL_PROJECTION);
-    glLoadIdentity();
-    glFrustum(-0.5f, 0.5f, -0.5f, 0.5f, 1.0f, 3.0f);
+    SetCurrent(*canvas);
 
+    // set up the parameters we want to use
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_LIGHTING);
     glEnable(GL_LIGHT0);
+    glEnable(GL_TEXTURE_2D);
 
-    // create the list of commands to draw the cube: then we can just (quickly)
-    // execute it in DrawRotatedCube() later
-    m_gllist = glGenLists(1);
-    glNewList(m_gllist, GL_COMPILE);
+    // add slightly more light, the default lighting is rather dark
+    GLfloat ambient[] = { 0.5, 0.5, 0.5, 0.5 };
+    glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
 
-    /* draw six faces of a cube */
-    glBegin(GL_QUADS);
-    glNormal3f( 0.0f, 0.0f, 1.0f);
-    glVertex3f( 0.5f, 0.5f, 0.5f); glVertex3f(-0.5f, 0.5f, 0.5f);
-    glVertex3f(-0.5f,-0.5f, 0.5f); glVertex3f( 0.5f,-0.5f, 0.5f);
+    // set viewing projection
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    glFrustum(-0.5f, 0.5f, -0.5f, 0.5f, 1.0f, 3.0f);
 
-    glNormal3f( 0.0f, 0.0f,-1.0f);
-    glVertex3f(-0.5f,-0.5f,-0.5f); glVertex3f(-0.5f, 0.5f,-0.5f);
-    glVertex3f( 0.5f, 0.5f,-0.5f); glVertex3f( 0.5f,-0.5f,-0.5f);
+    // create the textures to use for cube sides: they will be reused by all
+    // canvases (which is probably not critical in the case of simple textures
+    // we use here but could be really important for a real application where
+    // each texture could take many megabytes)
+    glGenTextures(WXSIZEOF(m_textures), m_textures);
 
-    glNormal3f( 0.0f, 1.0f, 0.0f);
-    glVertex3f( 0.5f, 0.5f, 0.5f); glVertex3f( 0.5f, 0.5f,-0.5f);
-    glVertex3f(-0.5f, 0.5f,-0.5f); glVertex3f(-0.5f, 0.5f, 0.5f);
+    for ( unsigned i = 0; i < WXSIZEOF(m_textures); i++ )
+    {
+        glBindTexture(GL_TEXTURE_2D, m_textures[i]);
 
-    glNormal3f( 0.0f,-1.0f, 0.0f);
-    glVertex3f(-0.5f,-0.5f,-0.5f); glVertex3f( 0.5f,-0.5f,-0.5f);
-    glVertex3f( 0.5f,-0.5f, 0.5f); glVertex3f(-0.5f,-0.5f, 0.5f);
+        glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 
-    glNormal3f( 1.0f, 0.0f, 0.0f);
-    glVertex3f( 0.5f, 0.5f, 0.5f); glVertex3f( 0.5f,-0.5f, 0.5f);
-    glVertex3f( 0.5f,-0.5f,-0.5f); glVertex3f( 0.5f, 0.5f,-0.5f);
+        const wxImage img(DrawDice(256, i + 1));
 
-    glNormal3f(-1.0f, 0.0f, 0.0f);
-    glVertex3f(-0.5f,-0.5f,-0.5f); glVertex3f(-0.5f,-0.5f, 0.5f);
-    glVertex3f(-0.5f, 0.5f, 0.5f); glVertex3f(-0.5f, 0.5f,-0.5f);
-    glEnd();
+        glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img.GetWidth(), img.GetHeight(), 
+                     0, GL_RGB, GL_UNSIGNED_BYTE, img.GetData());
+    }
 
-    glEndList();
+    CheckGLError();
 }
 
 void TestGLContext::DrawRotatedCube(float xangle, float yangle)
 {
-    Init();
-
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
     glMatrixMode(GL_MODELVIEW);
@@ -147,9 +178,102 @@ void TestGLContext::DrawRotatedCube(float xangle, float yangle)
     glRotatef(xangle, 1.0f, 0.0f, 0.0f);
     glRotatef(yangle, 0.0f, 1.0f, 0.0f);
 
-    glCallList(m_gllist);
+    // draw six faces of a cube of size 1 centered at (0, 0, 0)
+    glBindTexture(GL_TEXTURE_2D, m_textures[0]);
+    glBegin(GL_QUADS);
+        glNormal3f( 0.0f, 0.0f, 1.0f);
+        glTexCoord2f(0, 0); glVertex3f( 0.5f, 0.5f, 0.5f);
+        glTexCoord2f(1, 0); glVertex3f(-0.5f, 0.5f, 0.5f);
+        glTexCoord2f(1, 1); glVertex3f(-0.5f,-0.5f, 0.5f);
+        glTexCoord2f(0, 1); glVertex3f( 0.5f,-0.5f, 0.5f);
+    glEnd();
+
+    glBindTexture(GL_TEXTURE_2D, m_textures[1]);
+    glBegin(GL_QUADS);
+        glNormal3f( 0.0f, 0.0f,-1.0f);
+        glTexCoord2f(0, 0); glVertex3f(-0.5f,-0.5f,-0.5f);
+        glTexCoord2f(1, 0); glVertex3f(-0.5f, 0.5f,-0.5f);
+        glTexCoord2f(1, 1); glVertex3f( 0.5f, 0.5f,-0.5f);
+        glTexCoord2f(0, 1); glVertex3f( 0.5f,-0.5f,-0.5f);
+    glEnd();
+
+    glBindTexture(GL_TEXTURE_2D, m_textures[2]);
+    glBegin(GL_QUADS);
+        glNormal3f( 0.0f, 1.0f, 0.0f);
+        glTexCoord2f(0, 0); glVertex3f( 0.5f, 0.5f, 0.5f);
+        glTexCoord2f(1, 0); glVertex3f( 0.5f, 0.5f,-0.5f);
+        glTexCoord2f(1, 1); glVertex3f(-0.5f, 0.5f,-0.5f);
+        glTexCoord2f(0, 1); glVertex3f(-0.5f, 0.5f, 0.5f);
+    glEnd();
+
+    glBindTexture(GL_TEXTURE_2D, m_textures[3]);
+    glBegin(GL_QUADS);
+        glNormal3f( 0.0f,-1.0f, 0.0f);
+        glTexCoord2f(0, 0); glVertex3f(-0.5f,-0.5f,-0.5f);
+        glTexCoord2f(1, 0); glVertex3f( 0.5f,-0.5f,-0.5f);
+        glTexCoord2f(1, 1); glVertex3f( 0.5f,-0.5f, 0.5f);
+        glTexCoord2f(0, 1); glVertex3f(-0.5f,-0.5f, 0.5f);
+    glEnd();
+
+    glBindTexture(GL_TEXTURE_2D, m_textures[4]);
+    glBegin(GL_QUADS);
+        glNormal3f( 1.0f, 0.0f, 0.0f);
+        glTexCoord2f(0, 0); glVertex3f( 0.5f, 0.5f, 0.5f);
+        glTexCoord2f(1, 0); glVertex3f( 0.5f,-0.5f, 0.5f);
+        glTexCoord2f(1, 1); glVertex3f( 0.5f,-0.5f,-0.5f);
+        glTexCoord2f(0, 1); glVertex3f( 0.5f, 0.5f,-0.5f);
+    glEnd();
+
+    glBindTexture(GL_TEXTURE_2D, m_textures[5]);
+    glBegin(GL_QUADS);
+        glNormal3f(-1.0f, 0.0f, 0.0f);
+        glTexCoord2f(0, 0); glVertex3f(-0.5f,-0.5f,-0.5f);
+        glTexCoord2f(1, 0); glVertex3f(-0.5f,-0.5f, 0.5f);
+        glTexCoord2f(1, 1); glVertex3f(-0.5f, 0.5f, 0.5f);
+        glTexCoord2f(0, 1); glVertex3f(-0.5f, 0.5f,-0.5f);
+    glEnd();
 
     glFlush();
+
+    CheckGLError();
+}
+
+
+// ----------------------------------------------------------------------------
+// MyApp: the application object
+// ----------------------------------------------------------------------------
+
+IMPLEMENT_APP(MyApp)
+
+bool MyApp::OnInit()
+{
+    if ( !wxApp::OnInit() )
+        return false;
+
+    new MyFrame();
+
+    return true;
+}
+
+int MyApp::OnExit()
+{
+    delete m_glContext;
+
+    return wxApp::OnExit();
+}
+
+TestGLContext& MyApp::GetContext(wxGLCanvas *canvas)
+{
+    if ( !m_glContext )
+    {
+        // Create the OpenGL context for the first window which needs it:
+        // subsequently created windows will all share the same context.
+        m_glContext = new TestGLContext(canvas);
+    }
+
+    m_glContext->SetCurrent(*canvas);
+
+    return *m_glContext;
 }
 
 // ----------------------------------------------------------------------------
@@ -157,14 +281,18 @@ void TestGLContext::DrawRotatedCube(float xangle, float yangle)
 // ----------------------------------------------------------------------------
 
 BEGIN_EVENT_TABLE(TestGLCanvas, wxGLCanvas)
-    EVT_SIZE(TestGLCanvas::OnSize)
     EVT_PAINT(TestGLCanvas::OnPaint)
-
     EVT_KEY_DOWN(TestGLCanvas::OnKeyDown)
 END_EVENT_TABLE()
 
 TestGLCanvas::TestGLCanvas(wxWindow *parent)
-            : wxGLCanvas(parent, wxID_ANY, NULL /* attribs */)
+    // With perspective OpenGL graphics, the wxFULL_REPAINT_ON_RESIZE style
+    // flag should always be set, because even making the canvas smaller should
+    // be followed by a paint event that updates the entire canvas with new
+    // viewport settings.
+    : wxGLCanvas(parent, wxID_ANY, NULL /* attribs */,
+                 wxDefaultPosition, wxDefaultSize,
+                 wxFULL_REPAINT_ON_RESIZE)
 {
     m_xangle =
     m_yangle = 30;
@@ -172,27 +300,22 @@ TestGLCanvas::TestGLCanvas(wxWindow *parent)
 
 void TestGLCanvas::OnPaint(wxPaintEvent& WXUNUSED(event))
 {
+    // This is required even though dc is not used otherwise.
     wxPaintDC dc(this);
 
-    wxGetApp().GetContext(this).DrawRotatedCube(m_xangle, m_yangle);
-
-    SwapBuffers();
-}
+    // Set the OpenGL viewport according to the client size of this canvas.
+    // This is done here rather than in a wxSizeEvent handler because our
+    // OpenGL rendering context (and thus viewport setting) is used with
+    // multiple canvases: If we updated the viewport in the wxSizeEvent
+    // handler, changing the size of one canvas causes a viewport setting that
+    // is wrong when next another canvas is repainted.
+    const wxSize ClientSize = GetClientSize();
 
-void TestGLCanvas::OnSize(wxSizeEvent& event)
-{
-    // don't prevent default processing from taking place
-    event.Skip();
+    glViewport(0, 0, ClientSize.x, ClientSize.y);
 
-    if ( !IsShown() )
-        return;
-
-    // set GL viewport (not called by wxGLCanvas::OnSize on all platforms...)
-    int w, h;
-    GetClientSize(&w, &h);
-
-    wxGetApp().GetContext(this);
-    glViewport(0, 0, w, h);
+    // Render the graphics and swap the buffers.
+    wxGetApp().GetContext(this).DrawRotatedCube(m_xangle, m_yangle);
+    SwapBuffers();
 }
 
 void TestGLCanvas::OnKeyDown( wxKeyEvent& event )
@@ -235,6 +358,7 @@ void TestGLCanvas::OnKeyDown( wxKeyEvent& event )
     Refresh(false);
 }
 
+
 // ----------------------------------------------------------------------------
 // MyFrame: main application window
 // ----------------------------------------------------------------------------
@@ -265,6 +389,11 @@ MyFrame::MyFrame()
 
     SetClientSize(400, 400);
     Show();
+
+    // test IsDisplaySupported() function:
+    static const int attribs[] = { WX_GL_RGBA, WX_GL_DOUBLEBUFFER, 0 };
+    wxLogStatus("Double-buffered display %s supported",
+                wxGLCanvas::IsDisplaySupported(attribs) ? "is" : "not");
 }
 
 void MyFrame::OnClose(wxCommandEvent& WXUNUSED(event))
@@ -275,6 +404,6 @@ void MyFrame::OnClose(wxCommandEvent& WXUNUSED(event))
 
 void MyFrame::OnNewWindow( wxCommandEvent& WXUNUSED(event) )
 {
-    (void) new MyFrame();
+    new MyFrame();
 }