wxWidgets/samples/opengl/cube/cube.cpp

401 lines
11 KiB
C++

///////////////////////////////////////////////////////////////////////////////
// Name: cube.cpp
// Purpose: wxGLCanvas demo program
// Author: Julian Smart
// Modified by: Vadim Zeitlin to use new wxGLCanvas API (2007-04-09)
// Created: 04/01/98
// RCS-ID: $Id$
// Copyright: (c) Julian Smart
// Licence: wxWindows licence
///////////////////////////////////////////////////////////////////////////////
// ============================================================================
// declarations
// ============================================================================
// ----------------------------------------------------------------------------
// headers
// ----------------------------------------------------------------------------
// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"
#ifdef __BORLANDC__
#pragma hdrstop
#endif
#ifndef WX_PRECOMP
#include "wx/wx.h"
#endif
#if !wxUSE_GLCANVAS
#error "OpenGL required: set wxUSE_GLCANVAS to 1 and rebuild the library"
#endif
#include "cube.h"
#if !defined(__WXMSW__) && !defined(__WXPM__)
#include "../../sample.xpm"
#endif
// ----------------------------------------------------------------------------
// helper functions
// ----------------------------------------------------------------------------
static void CheckGLError()
{
GLenum errLast = GL_NO_ERROR;
for ( ;; )
{
GLenum err = glGetError();
if ( err == GL_NO_ERROR )
return;
// 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;
}
errLast = err;
wxLogError(_T("OpenGL error %d"), err);
}
}
// function to draw the texture for cube faces
static wxImage DrawDice(int size, unsigned num)
{
wxASSERT_MSG( num >= 1 && num <= 6, _T("invalid dice index") );
const int dot = size/16; // radius of a single dot
const int gap = 5*size/32; // gap between dots
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
// ============================================================================
// ----------------------------------------------------------------------------
// MyApp: the application object
// ----------------------------------------------------------------------------
IMPLEMENT_APP(MyApp)
bool MyApp::OnInit()
{
if ( !wxApp::OnInit() )
return false;
// Create the main window
new MyFrame();
return true;
}
int MyApp::OnExit()
{
delete m_glContext;
return wxApp::OnExit();
}
TestGLContext& MyApp::GetContext(wxGLCanvas *canvas)
{
if ( !m_glContext )
m_glContext = new TestGLContext(canvas);
else
m_glContext->SetCurrent(*canvas);
return *m_glContext;
}
// ----------------------------------------------------------------------------
// TestGLContext
// ----------------------------------------------------------------------------
TestGLContext::TestGLContext(wxGLCanvas *canvas)
: wxGLContext(canvas)
{
SetCurrent(*canvas);
// set up the parameters we want to use
glEnable(GL_DEPTH_TEST);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_TEXTURE_2D);
// add slightly more light, the default lightning is rather dark
GLfloat ambient[] = { 0.5, 0.5, 0.5, 0.5 };
glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
// set viewing projection
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glFrustum(-0.5f, 0.5f, -0.5f, 0.5f, 1.0f, 3.0f);
// 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);
for ( unsigned i = 0; i < WXSIZEOF(m_textures); i++ )
{
glBindTexture(GL_TEXTURE_2D, m_textures[i]);
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);
const wxImage img(DrawDice(256, i + 1));
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img.GetWidth(), img.GetHeight(),
0, GL_RGB, GL_UNSIGNED_BYTE, img.GetData());
}
CheckGLError();
}
void TestGLContext::DrawRotatedCube(float xangle, float yangle)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0.0f, 0.0f, -2.0f);
glRotatef(xangle, 1.0f, 0.0f, 0.0f);
glRotatef(yangle, 0.0f, 1.0f, 0.0f);
// 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();
}
// ----------------------------------------------------------------------------
// TestGLCanvas
// ----------------------------------------------------------------------------
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 */)
{
m_xangle =
m_yangle = 30;
}
void TestGLCanvas::OnPaint(wxPaintEvent& WXUNUSED(event))
{
wxPaintDC dc(this);
wxGetApp().GetContext(this).DrawRotatedCube(m_xangle, m_yangle);
SwapBuffers();
}
void TestGLCanvas::OnSize(wxSizeEvent& event)
{
// don't prevent default processing from taking place
event.Skip();
if ( !IsShownOnScreen() )
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);
}
void TestGLCanvas::OnKeyDown( wxKeyEvent& event )
{
float *p = NULL;
bool inverse = false;
switch ( event.GetKeyCode() )
{
case WXK_RIGHT:
inverse = true;
// fall through
case WXK_LEFT:
// rotate around Y axis
p = &m_yangle;
break;
case WXK_DOWN:
inverse = true;
// fall through
case WXK_UP:
// rotate around X axis
p = &m_xangle;
break;
default:
event.Skip();
return;
}
float angle = 5;
if ( inverse )
angle = -angle;
*p += angle;
Refresh(false);
}
// ----------------------------------------------------------------------------
// MyFrame: main application window
// ----------------------------------------------------------------------------
BEGIN_EVENT_TABLE(MyFrame, wxFrame)
EVT_MENU(wxID_NEW, MyFrame::OnNewWindow)
EVT_MENU(wxID_CLOSE, MyFrame::OnClose)
END_EVENT_TABLE()
MyFrame::MyFrame()
: wxFrame(NULL, wxID_ANY, _T("wxWidgets OpenGL Cube Sample"))
{
new TestGLCanvas(this);
SetIcon(wxICON(sample));
// Make a menubar
wxMenu *menu = new wxMenu;
menu->Append(wxID_NEW);
menu->AppendSeparator();
menu->Append(wxID_CLOSE);
wxMenuBar *menuBar = new wxMenuBar;
menuBar->Append(menu, _T("&Cube"));
SetMenuBar(menuBar);
CreateStatusBar();
SetClientSize(400, 400);
Show();
}
void MyFrame::OnClose(wxCommandEvent& WXUNUSED(event))
{
// true is to force the frame to close
Close(true);
}
void MyFrame::OnNewWindow( wxCommandEvent& WXUNUSED(event) )
{
(void) new MyFrame();
}