OpenGL 로 간단하게 2D Drawing 하는 기본 소스

OpenGL 로 간단하게 2D 드로잉 하는 걸 공부하고 있는데 진도가 느리다.

아래 소스는 Visual C++ 에서 OpenGL을 이용하여 간단하게 2D 드로잉을 하는 기본 소스이다.

// stdafx.h //////////////////////////////////////////////////////////////////////////////// // for OpenGL #pragma comment (lib, "opengl32.lib") #pragma comment (lib, "glu32.lib") #pragma comment (lib, "glaux.lib") #include <gl/GL.h> #include <gl/GLU.h> #include <gl/GLAux.h> // for OpenGL //////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////// // Header HGLRC m_hRC; //Rendering Context CDC* m_pDC; //Device Context int m_nPixelFormat; BOOL InitializeOpenGL(); void RenderScene(); //////////////////////////////////////////////////////////////////////////////// // Source int CGLTestView::OnCreate(LPCREATESTRUCT lpCreateStruct) { if (CView::OnCreate(lpCreateStruct) == -1) return -1; InitializeOpenGL(); return 0; } BOOL CGLTestView::InitializeOpenGL() { //Get a DC for the Client Area m_pDC = new CClientDC(this); //Failure to Get DC if(m_pDC == NULL) { MessageBox( _T("Error Obtaining DC") ); return FALSE; } //////////////////////////////////////////////////////////////////////////////// // Setup Pixel Format static PIXELFORMATDESCRIPTOR pfd = { sizeof(PIXELFORMATDESCRIPTOR), // size of this pfd 1, // version number PFD_DRAW_TO_WINDOW | // support window PFD_SUPPORT_OPENGL | // support OpenGL PFD_DOUBLEBUFFER, // double buffered PFD_TYPE_RGBA, // RGBA type 32, // color depth 0, 0, 0, 0, 0, 0, // color bits ignored 0, // no alpha buffer 0, // shift bit ignored 0, // no accumulation buffer 0, 0, 0, 0, // accumulation bits ignored 32, // z-buffer 0, // no stencil buffer 0, // no auxiliary buffer PFD_MAIN_PLANE, // main layer 0, // reserved 0, 0, 0 // layer masks ignored }; int m_nPixelFormat = ::ChoosePixelFormat( m_pDC->GetSafeHdc(), &pfd ); if ( m_nPixelFormat == 0 ) { return FALSE; } if ( ::SetPixelFormat( m_pDC->GetSafeHdc(), m_nPixelFormat, &pfd ) == FALSE ) { return FALSE; } //////////////////////////////////////////////////////////////////////////////// //Create Rendering Context m_hRC = ::wglCreateContext( m_pDC->GetSafeHdc() ); //Failure to Create Rendering Context if( m_hRC == 0 ) { MessageBox( _T("Error Creating RC") ); return FALSE; } //Make the RC Current if( ::wglMakeCurrent ( m_pDC->GetSafeHdc (), m_hRC ) == FALSE ) { MessageBox( _T("Error making RC Current") ); return FALSE; } //Specify Black as the clear color ::glClearColor( 0.0f, 0.0f, 0.0f, 0.0f); //Specify the back of the buffer as clear depth //::glClearDepth( 1.0f ); //Enable Depth Testing //::glEnable( GL_DEPTH_TEST ); ::glDisable( GL_DEPTH_TEST ); // For 2D return TRUE; } void CGLTestView::OnDraw(CDC* /*pDC*/) { CGLTestDoc* pDoc = GetDocument(); ASSERT_VALID(pDoc); if (!pDoc) return; // 컬러버퍼와 깊이버퍼를 초기화 glClearColor(0.0f, 0.0f, 0.0f, 0.0f); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); RenderScene(); // Tell OpenGL to flush its pipeline ::glFinish(); // Now Swap the buffers ::SwapBuffers( m_pDC->GetSafeHdc() ); } void CGLTestView::RenderScene() { glBegin(GL_TRIANGLES); { glVertex2f( 0.0f, 0.0f ); glVertex2f( 20.0f, 0.0f ); glVertex2f( 0.0f, 20.0f ); } glEnd(); } void CGLTestView::OnSize(UINT nType, int cx, int cy) { CView::OnSize(nType, cx, cy); GLdouble aspect_ratio; // width/height ratio if ( 0 >= cx || 0 >= cy ) { return; } // select the full client area ::glViewport(0, 0, cx, cy); // compute the aspect ratio // this will keep all dimension scales equal aspect_ratio = (GLdouble)cx/(GLdouble)cy; // select the projection matrix and clear it ::glMatrixMode(GL_PROJECTION); ::glLoadIdentity(); // select the viewing volume //::gluPerspective(45.0f, aspect_ratio, .01f, 200.0f); GLfloat nRange = 50.0f; if (cx <= cy) { glOrtho(-nRange, nRange, -nRange * cy / cx, nRange * cy / cx, -nRange, nRange ); } else { glOrtho(-nRange * cx / cy, nRange * cx / cy, -nRange, nRange, -nRange, nRange); } // switch back to the modelview matrix and clear it ::glMatrixMode(GL_MODELVIEW); ::glLoadIdentity(); }

결과 화면

glut를 사용하지 않고 기본으로 포함되어있는 OpenGL 만을 이용한 소스이다. 분석을 하여 나중에는 glut까지 이용하는 코드를 작성해 보아야겠다.

GLTest.7z