src/common/glcmn.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/glcmn.cpp
   3 // Purpose:     wxGLCanvasBase implementation
   4 // Author:      Vadim Zeitlin
   5 // Created:     2007-04-09
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2007 Vadim Zeitlin <vadim@wxwindows.org>
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 // ============================================================================
  12 // declarations
  13 // ============================================================================
  14
  15 // ----------------------------------------------------------------------------
  16 // headers
  17 // ----------------------------------------------------------------------------
  18
  19 // for compilers that support precompilation, includes "wx.h".
  20 #include "wx/wxprec.h"
  21
  22 #ifdef __BORLANDC__
  23     #pragma hdrstop
  24 #endif
  25
  26 #if wxUSE_GLCANVAS
  27
  28 #ifndef WX_PRECOMP
  29     #include "wx/log.h"
  30 #endif // WX_PRECOMP
  31
  32 #include "wx/glcanvas.h"
  33
  34 // DLL options compatibility check:
  35 #include "wx/build.h"
  36 WX_CHECK_BUILD_OPTIONS("wxGL")
  37
  38 IMPLEMENT_CLASS(wxGLApp, wxApp)
  39
  40 // ============================================================================
  41 // implementation
  42 // ============================================================================
  43
  44 wxGLCanvasBase::wxGLCanvasBase()
  45 {
  46 #if WXWIN_COMPATIBILITY_2_8
  47     m_glContext = NULL;
  48 #endif
  49
  50     // we always paint background entirely ourselves so prevent wx from erasing
  51     // it to avoid flicker
  52     SetBackgroundStyle(wxBG_STYLE_CUSTOM);
  53 }
  54
  55 bool wxGLCanvasBase::SetCurrent(const wxGLContext& context) const
  56 {
  57     // although on MSW it works even if the window is still hidden, it doesn't
  58     // work in other ports (notably X11-based ones) and documentation mentions
  59     // that SetCurrent() can only be called for a shown window, so check for it
  60     wxASSERT_MSG( IsShownOnScreen(), wxT("can't make hidden GL canvas current") );
  61
  62
  63     return context.SetCurrent(*static_cast<const wxGLCanvas *>(this));
  64 }
  65
  66 bool wxGLCanvasBase::SetColour(const wxString& colour)
  67 {
  68     wxColour col = wxTheColourDatabase->Find(colour);
  69     if ( !col.IsOk() )
  70         return false;
  71
  72 #ifdef wxHAS_OPENGL_ES
  73     wxGLAPI::glColor3f((GLfloat) (col.Red() / 256.), (GLfloat) (col.Green() / 256.),
  74                 (GLfloat) (col.Blue() / 256.));
  75 #else
  76     GLboolean isRGBA;
  77     glGetBooleanv(GL_RGBA_MODE, &isRGBA);
  78     if ( isRGBA )
  79     {
  80         glColor3f((GLfloat) (col.Red() / 256.), (GLfloat) (col.Green() / 256.),
  81                 (GLfloat) (col.Blue() / 256.));
  82     }
  83     else // indexed colour
  84     {
  85         GLint pix = GetColourIndex(col);
  86         if ( pix == -1 )
  87         {
  88             wxLogError(_("Failed to allocate colour for OpenGL"));
  89             return false;
  90         }
  91
  92         glIndexi(pix);
  93     }
  94 #endif
  95     return true;
  96 }
  97
  98 wxGLCanvasBase::~wxGLCanvasBase()
  99 {
 100 #if WXWIN_COMPATIBILITY_2_8
 101     delete m_glContext;
 102 #endif // WXWIN_COMPATIBILITY_2_8
 103 }
 104
 105 #if WXWIN_COMPATIBILITY_2_8
 106
 107 wxGLContext *wxGLCanvasBase::GetContext() const
 108 {
 109     return m_glContext;
 110 }
 111
 112 void wxGLCanvasBase::SetCurrent()
 113 {
 114     if ( m_glContext )
 115         SetCurrent(*m_glContext);
 116 }
 117
 118 void wxGLCanvasBase::OnSize(wxSizeEvent& WXUNUSED(event))
 119 {
 120 }
 121
 122 #endif // WXWIN_COMPATIBILITY_2_8
 123
 124 /* static */
 125 bool wxGLCanvasBase::IsExtensionInList(const char *list, const char *extension)
 126 {
 127     if ( !list )
 128         return false;
 129
 130     for ( const char *p = list; *p; p++ )
 131     {
 132         // advance up to the next possible match
 133         p = wxStrstr(p, extension);
 134         if ( !p )
 135             break;
 136
 137         // check that the extension appears at the beginning/ending of the list
 138         // or is preceded/followed by a space to avoid mistakenly finding
 139         // "glExtension" in a list containing some "glFunkyglExtension"
 140         if ( (p == list || p[-1] == ' ') )
 141         {
 142             char c = p[strlen(extension)];
 143             if ( c == '\0' || c == ' ' )
 144                 return true;
 145         }
 146     }
 147
 148     return false;
 149 }
 150
 151 // ============================================================================
 152 // compatibility layer for OpenGL 3 and OpenGL ES
 153 // ============================================================================
 154
 155 static wxGLAPI s_glAPI;
 156
 157 #if wxUSE_OPENGL_EMULATION
 158
 159 #include "wx/vector.h"
 160
 161 static GLenum s_mode;
 162
 163 static GLfloat s_currentTexCoord[2];
 164 static GLfloat s_currentColor[4];
 165 static GLfloat s_currentNormal[3];
 166
 167 // TODO move this into a different construct with locality for all attributes
 168 // of a vertex
 169
 170 static wxVector<GLfloat> s_texCoords;
 171 static wxVector<GLfloat> s_vertices;
 172 static wxVector<GLfloat> s_normals;
 173 static wxVector<GLfloat> s_colors;
 174
 175 static bool s_texCoordsUsed;
 176 static bool s_colorsUsed;
 177 static bool s_normalsUsed;
 178
 179 bool SetState( int flag, bool desired )
 180 {
 181     bool former = glIsEnabled( flag );
 182     if ( former != desired )
 183     {
 184         if ( desired )
 185             glEnableClientState(flag);
 186         else
 187             glDisableClientState(flag);
 188     }
 189     return former;
 190 }
 191
 192 void RestoreState( int flag, bool desired )
 193 {
 194     if ( desired )
 195         glEnableClientState(flag);
 196     else
 197         glDisableClientState(flag);
 198 }
 199 #endif
 200
 201 wxGLAPI::wxGLAPI()
 202 {
 203 #if wxUSE_OPENGL_EMULATION
 204     s_mode = 0xFF;
 205 #endif
 206 }
 207
 208 wxGLAPI::~wxGLAPI()
 209 {
 210 }
 211
 212 void wxGLAPI::glFrustum(GLfloat left, GLfloat right, GLfloat bottom,
 213                             GLfloat top, GLfloat zNear, GLfloat zFar)
 214 {
 215 #if wxUSE_OPENGL_EMULATION
 216     ::glFrustumf(left, right, bottom, top, zNear, zFar);
 217 #else
 218     ::glFrustum(left, right, bottom, top, zNear, zFar);
 219 #endif
 220 }
 221
 222 void wxGLAPI::glBegin(GLenum mode)
 223 {
 224 #if wxUSE_OPENGL_EMULATION
 225     if ( s_mode != 0xFF )
 226     {
 227         wxFAIL_MSG("nested glBegin");
 228     }
 229
 230     s_mode = mode;
 231     s_texCoordsUsed = false;
 232     s_colorsUsed = false;
 233     s_normalsUsed = false;
 234
 235     s_texCoords.clear();
 236     s_normals.clear();
 237     s_colors.clear();
 238     s_vertices.clear();
 239 #else
 240     ::glBegin(mode);
 241 #endif
 242 }
 243
 244 void wxGLAPI::glTexCoord2f(GLfloat s, GLfloat t)
 245 {
 246 #if wxUSE_OPENGL_EMULATION
 247     if ( s_mode == 0xFF )
 248     {
 249         wxFAIL_MSG("glTexCoord2f called outside glBegin/glEnd");
 250     }
 251
 252     else
 253     {
 254         s_texCoordsUsed = true;
 255         s_currentTexCoord[0] = s;
 256         s_currentTexCoord[1] = t;
 257     }
 258 #else
 259     ::glTexCoord2f(s,t);
 260 #endif
 261 }
 262
 263 void wxGLAPI::glVertex3f(GLfloat x, GLfloat y, GLfloat z)
 264 {
 265 #if wxUSE_OPENGL_EMULATION
 266     if ( s_mode == 0xFF )
 267     {
 268         wxFAIL_MSG("glVertex3f called outside glBegin/glEnd");
 269     }
 270     else
 271     {
 272         s_texCoords.push_back(s_currentTexCoord[0]);
 273         s_texCoords.push_back(s_currentTexCoord[1]);
 274
 275         s_normals.push_back(s_currentNormal[0]);
 276         s_normals.push_back(s_currentNormal[1]);
 277         s_normals.push_back(s_currentNormal[2]);
 278
 279         s_colors.push_back(s_currentColor[0]);
 280         s_colors.push_back(s_currentColor[1]);
 281         s_colors.push_back(s_currentColor[2]);
 282         s_colors.push_back(s_currentColor[3]);
 283
 284         s_vertices.push_back(x);
 285         s_vertices.push_back(y);
 286         s_vertices.push_back(z);
 287     }
 288 #else
 289     ::glVertex3f(x,y,z);
 290 #endif
 291 }
 292
 293 void wxGLAPI::glNormal3f(GLfloat nx, GLfloat ny, GLfloat nz)
 294 {
 295 #if wxUSE_OPENGL_EMULATION
 296     if ( s_mode == 0xFF )
 297         ::glNormal3f(nx,ny,nz);
 298     else
 299     {
 300         s_normalsUsed = true;
 301         s_currentNormal[0] = nx;
 302         s_currentNormal[1] = ny;
 303         s_currentNormal[2] = nz;
 304     }
 305 #else
 306     ::glNormal3f(nx,ny,nz);
 307 #endif
 308 }
 309
 310 void wxGLAPI::glColor4f(GLfloat r, GLfloat g, GLfloat b, GLfloat a)
 311 {
 312 #if wxUSE_OPENGL_EMULATION
 313     if ( s_mode == 0xFF )
 314         ::glColor4f(r,g,b,a);
 315     else
 316     {
 317         s_colorsUsed = true;
 318         s_currentColor[0] = r;
 319         s_currentColor[1] = g;
 320         s_currentColor[2] = b;
 321         s_currentColor[3] = a;
 322     }
 323 #else
 324     ::glColor4f(r,g,b,a);
 325 #endif
 326 }
 327
 328 void wxGLAPI::glColor3f(GLfloat r, GLfloat g, GLfloat b)
 329 {
 330 #if wxUSE_OPENGL_EMULATION
 331     glColor4f(r,g,b,1.0);
 332 #else
 333     ::glColor3f(r,g,b);
 334 #endif
 335 }
 336
 337 void wxGLAPI::glEnd()
 338 {
 339 #if wxUSE_OPENGL_EMULATION
 340     bool formerColors = SetState( GL_COLOR_ARRAY, s_colorsUsed );
 341     bool formerNormals = SetState( GL_NORMAL_ARRAY, s_normalsUsed );
 342     bool formerTexCoords = SetState( GL_TEXTURE_COORD_ARRAY, s_texCoordsUsed );
 343     bool formerVertex = glIsEnabled(GL_VERTEX_ARRAY);
 344
 345     if( !formerVertex )
 346         glEnableClientState(GL_VERTEX_ARRAY);
 347
 348     if ( s_colorsUsed )
 349         glColorPointer( 4, GL_FLOAT, 0, &s_colors[0] );
 350
 351     if ( s_normalsUsed )
 352         glNormalPointer( GL_FLOAT, 0, &s_normals[0] );
 353
 354     if ( s_texCoordsUsed )
 355         glTexCoordPointer( 2, GL_FLOAT, 0, &s_texCoords[0] );
 356
 357     glVertexPointer(3, GL_FLOAT, 0, &s_vertices[0]);
 358     glDrawArrays( s_mode, 0, s_vertices.size() / 3 );
 359
 360     if ( s_colorsUsed != formerColors )
 361         RestoreState( GL_COLOR_ARRAY, formerColors );
 362
 363     if ( s_normalsUsed != formerNormals )
 364         RestoreState( GL_NORMAL_ARRAY, formerColors );
 365
 366     if ( s_texCoordsUsed != formerTexCoords )
 367         RestoreState( GL_TEXTURE_COORD_ARRAY, formerColors );
 368
 369     if( !formerVertex )
 370         glDisableClientState(GL_VERTEX_ARRAY);
 371
 372     s_mode = 0xFF;
 373 #else
 374     ::glEnd();
 375 #endif
 376 }
 377
 378 #endif // wxUSE_GLCANVAS
 379