//
// "$Id: gl_draw.cxx,v 1.7.2.5.2.12 2004/04/11 04:39:00 easysw Exp $"
//
// OpenGL drawing support routines for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2004 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems to "fltk-bugs@fltk.org".
//

// Functions from <FL/gl.h>
// See also Fl_Gl_Window and gl_start.cxx

#include "flstring.h"
#if HAVE_GL

#include <FL/Fl.H>
#include <FL/gl.h>
#include <FL/x.H>
#include <FL/fl_draw.H>
#include "Fl_Gl_Choice.H"
#include "Fl_Font.H"

#if USE_XFT
extern XFontStruct* fl_xxfont();
#endif // USE_XFT

int   gl_height() {return fl_height();}
int   gl_descent() {return fl_descent();}
double gl_width(const char* s) {return fl_width(s);}
double gl_width(const char* s, int n) {return fl_width(s,n);}
double gl_width(uchar c) {return fl_width(c);}

void  gl_font(int fontid, int size) {
  fl_font(fontid, size);
  if (!fl_fontsize->listbase) {
#ifdef WIN32
    int base = fl_fontsize->metr.tmFirstChar;
    int count = fl_fontsize->metr.tmLastChar-base+1;
    HFONT oldFid = (HFONT)SelectObject(fl_gc, fl_fontsize->fid);
    fl_fontsize->listbase = glGenLists(256);
    wglUseFontBitmaps(fl_gc, base, count, fl_fontsize->listbase+base); 
    SelectObject(fl_gc, oldFid);
#elif defined(__APPLE__)
    // undefined characters automatically receive an empty GL list in aglUseFont
    fl_fontsize->listbase = glGenLists(256);
    aglUseFont(aglGetCurrentContext(), fl_fontsize->font, fl_fontsize->face,
               fl_fontsize->size, 0, 256, fl_fontsize->listbase);
#else
#  if USE_XFT
    fl_xfont = fl_xxfont();
#  endif // USE_XFT
    int base = fl_xfont->min_char_or_byte2;
    int count = fl_xfont->max_char_or_byte2-base+1;
    fl_fontsize->listbase = glGenLists(256);
    glXUseXFont(fl_xfont->fid, base, count, fl_fontsize->listbase+base);
#endif
  }
  glListBase(fl_fontsize->listbase);
}

void gl_draw(const char* str, int n) {
  glCallLists(n, GL_UNSIGNED_BYTE, str);
}

void gl_draw(const char* str, int n, int x, int y) {
  glRasterPos2i(x, y);
  gl_draw(str, n);
}

void gl_draw(const char* str, int n, float x, float y) {
  glRasterPos2f(x, y);
  gl_draw(str, n);
}

void gl_draw(const char* str) {
  gl_draw(str, strlen(str));
}

void gl_draw(const char* str, int x, int y) {
  gl_draw(str, strlen(str), x, y);
}

void gl_draw(const char* str, float x, float y) {
  gl_draw(str, strlen(str), x, y);
}

static void gl_draw_invert(const char* str, int n, int x, int y) {
  glRasterPos2i(x, -y);
  gl_draw(str, n);
}

void gl_draw(
  const char* str, 	// the (multi-line) string
  int x, int y, int w, int h, 	// bounding box
  Fl_Align align) {
  fl_draw(str, x, -y-h, w, h, align, gl_draw_invert);
}

void gl_measure(const char* str, int& x, int& y) {fl_measure(str,x,y);}

void gl_rect(int x, int y, int w, int h) {
  if (w < 0) {w = -w; x = x-w;}
  if (h < 0) {h = -h; y = y-h;}
  glBegin(GL_LINE_STRIP);
  glVertex2i(x+w-1, y+h-1);
  glVertex2i(x+w-1, y);
  glVertex2i(x, y);
  glVertex2i(x, y+h-1);
  glVertex2i(x+w, y+h-1);
  glEnd();
}

#if HAVE_GL_OVERLAY
extern uchar fl_overlay;
extern int fl_overlay_depth;
#endif

void gl_color(Fl_Color i) {
#if HAVE_GL_OVERLAY
#ifdef WIN32
  if (fl_overlay && fl_overlay_depth) {
    if (fl_overlay_depth < 8) {
      // only black & white produce the expected colors.  This could
      // be improved by fixing the colormap set in Fl_Gl_Overlay.cxx
      int size = 1<<fl_overlay_depth;
      if (!i) glIndexi(size-2);
      else if (i >= size-2) glIndexi(size-1);
      else glIndexi(i);
    } else {
      glIndexi(i ? i : FL_GRAY_RAMP);
    }    
    return;
  }
#else
  if (fl_overlay) {glIndexi(int(fl_xpixel(i))); return;}
#endif
#endif
  uchar red, green, blue;
  Fl::get_color(i, red, green, blue);
  glColor3ub(red, green, blue);
}
  
void gl_draw_image(const uchar* b, int x, int y, int w, int h, int d, int ld) {
  if (!ld) ld = w*d;
  glPixelStorei(GL_UNPACK_ROW_LENGTH, ld/d);
  glRasterPos2i(x,y);
  glDrawPixels(w,h,d<4?GL_RGB:GL_RGBA,GL_UNSIGNED_BYTE,(const ulong*)b);
}

#endif

//
// End of "$Id: gl_draw.cxx,v 1.7.2.5.2.12 2004/04/11 04:39:00 easysw Exp $".
//