/////////////////////////////////////////////////////////////////////////////
// Name:        glcanvas.cpp
// Purpose:     wxGLCanvas, for using OpenGL with wxWindows under MS Windows
// Author:      Julian Smart
// Modified by:
// Created:     04/01/98
// RCS-ID:      $Id$
// Copyright:   (c) Julian Smart
// Licence:   	wxWindows licence
/////////////////////////////////////////////////////////////////////////////

#ifdef __GNUG__
#pragma implementation "glcanvas.h"
#endif

#include "wx/wxprec.h"

#if defined(__BORLANDC__)
#pragma hdrstop
#endif

#ifndef WX_PRECOMP
#include <wx/frame.h>
#endif

#include "GL/gl.h"

#include "glcanvas.h"

/*
 * GLContext implementation
 */

wxGLContext::wxGLContext(bool isRGB, wxWindow *win, const wxPalette& palette)
{
  m_window = win;

  m_hDC = (WXHDC) ::GetDC((HWND) win->GetHWND());

  SetupPixelFormat();
  SetupPalette(palette);

  m_glContext = wglCreateContext((HDC) m_hDC);
  wglMakeCurrent((HDC) m_hDC, m_glContext);
}

wxGLContext::~wxGLContext()
{
  if (m_glContext)
  {
    wglMakeCurrent(NULL, NULL);
	wglDeleteContext(m_glContext);
  }

  ::ReleaseDC((HWND) m_window->GetHWND(), (HDC) m_hDC);
}

void wxGLContext::SwapBuffers()
{
  if (m_glContext)
  {
    wglMakeCurrent((HDC) m_hDC, m_glContext);
    ::SwapBuffers((HDC) m_hDC);    //blits the backbuffer into DC
  }
}

void wxGLContext::SetCurrent()
{
  if (m_glContext)
  {
    wglMakeCurrent((HDC) m_hDC, m_glContext);
  }

/*
	setupPixelFormat(hDC);
	setupPalette(hDC);
*/
}

void wxGLContext::SetColour(const char *colour)
{
  float r = 0.0;
  float g = 0.0;
  float b = 0.0;
  wxColour *col = wxTheColourDatabase->FindColour(colour);
  if (col)
  {
    r = (float)(col->Red()/256.0);
    g = (float)(col->Green()/256.0);
    b = (float)(col->Blue()/256.0);
    glColor3f( r, g, b);
  }
}

void wxGLContext::SetupPixelFormat() // (HDC hDC)
{
    PIXELFORMATDESCRIPTOR pfd = {
	sizeof(PIXELFORMATDESCRIPTOR),	/* size */
	1,				/* version */
	PFD_SUPPORT_OPENGL |
	PFD_DRAW_TO_WINDOW |
	PFD_DOUBLEBUFFER,		/* support double-buffering */
	PFD_TYPE_RGBA,			/* color type */
	16,				/* prefered color depth */
	0, 0, 0, 0, 0, 0,		/* color bits (ignored) */
	0,				/* no alpha buffer */
	0,				/* alpha bits (ignored) */
	0,				/* no accumulation buffer */
	0, 0, 0, 0,			/* accum bits (ignored) */
	16,				/* depth buffer */
	0,				/* no stencil buffer */
	0,				/* no auxiliary buffers */
	PFD_MAIN_PLANE,			/* main layer */
	0,				/* reserved */
	0, 0, 0,			/* no layer, visible, damage masks */
    };
    int pixelFormat;

    pixelFormat = ChoosePixelFormat((HDC) m_hDC, &pfd);
    if (pixelFormat == 0) {
	MessageBox(WindowFromDC((HDC) m_hDC), "ChoosePixelFormat failed.", "Error",
		MB_ICONERROR | MB_OK);
	exit(1);
    }

    if (SetPixelFormat((HDC) m_hDC, pixelFormat, &pfd) != TRUE) {
	MessageBox(WindowFromDC((HDC) m_hDC), "SetPixelFormat failed.", "Error",
		MB_ICONERROR | MB_OK);
	exit(1);
    }
}

void wxGLContext::SetupPalette(const wxPalette& palette)
{
    int pixelFormat = GetPixelFormat((HDC) m_hDC);
    PIXELFORMATDESCRIPTOR pfd;

    DescribePixelFormat((HDC) m_hDC, pixelFormat, sizeof(PIXELFORMATDESCRIPTOR), &pfd);

    if (pfd.dwFlags & PFD_NEED_PALETTE)
    {
    }
    else
    {
	  return;
    }

    m_palette = palette;

    if ( !m_palette.Ok() )
    {
        m_palette = CreateDefaultPalette();
    }

    if (m_palette.Ok())
    {
        SelectPalette((HDC) m_hDC, (HPALETTE) m_palette.GetHPALETTE(), FALSE);
        RealizePalette((HDC) m_hDC);
    }
}

wxPalette wxGLContext::CreateDefaultPalette()
{
    PIXELFORMATDESCRIPTOR pfd;
    int paletteSize;
    int pixelFormat = GetPixelFormat((HDC) m_hDC);

    DescribePixelFormat((HDC) m_hDC, pixelFormat, sizeof(PIXELFORMATDESCRIPTOR), &pfd);

	paletteSize = 1 << pfd.cColorBits;

    LOGPALETTE* pPal =
     (LOGPALETTE*) malloc(sizeof(LOGPALETTE) + paletteSize * sizeof(PALETTEENTRY));
    pPal->palVersion = 0x300;
    pPal->palNumEntries = paletteSize;

    /* build a simple RGB color palette */
    {
	int redMask = (1 << pfd.cRedBits) - 1;
	int greenMask = (1 << pfd.cGreenBits) - 1;
	int blueMask = (1 << pfd.cBlueBits) - 1;
	int i;

	for (i=0; i<paletteSize; ++i) {
	    pPal->palPalEntry[i].peRed =
		    (((i >> pfd.cRedShift) & redMask) * 255) / redMask;
	    pPal->palPalEntry[i].peGreen =
		    (((i >> pfd.cGreenShift) & greenMask) * 255) / greenMask;
	    pPal->palPalEntry[i].peBlue =
		    (((i >> pfd.cBlueShift) & blueMask) * 255) / blueMask;
	    pPal->palPalEntry[i].peFlags = 0;
	}
    }

    HPALETTE hPalette = CreatePalette(pPal);
    free(pPal);

    wxPalette palette;
    palette.SetHPALETTE((WXHPALETTE) hPalette);

    return palette;
}

/*
 * wxGLCanvas implementation
 */

IMPLEMENT_CLASS(wxGLCanvas, wxScrolledWindow)

BEGIN_EVENT_TABLE(wxGLCanvas, wxScrolledWindow)
    EVT_SIZE(wxGLCanvas::OnSize)
    EVT_PALETTE_CHANGED(wxGLCanvas::OnPaletteChanged)
    EVT_QUERY_NEW_PALETTE(wxGLCanvas::OnQueryNewPalette)
END_EVENT_TABLE()

wxGLCanvas::wxGLCanvas(wxWindow *parent, wxWindowID id,
    const wxPoint& pos, const wxSize& size, long style, const wxString& name,
    int *attribList /* not used yet! */, const wxPalette& palette):
  wxScrolledWindow(parent, id, pos, size, style, name)
{
  m_glContext = new wxGLContext(TRUE, this, palette);
}

wxGLCanvas::~wxGLCanvas()
{
  if (m_glContext)
    delete m_glContext;
}

void wxGLCanvas::SwapBuffers()
{
  if (m_glContext)
    m_glContext->SwapBuffers();
}

void wxGLCanvas::OnSize(wxSizeEvent& event)
{
  int width, height;
  GetClientSize(& width, & height);

  if (m_glContext)
  {
    m_glContext->SetCurrent();

    glViewport(0, 0, (GLint)width, (GLint)height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glFrustum( -1.0, 1.0, -1.0, 1.0, 5.0, 15.0 );
    glMatrixMode(GL_MODELVIEW);
  }
}

void wxGLCanvas::SetCurrent()
{
  if (m_glContext)
  {
    m_glContext->SetCurrent();
  }
}

void wxGLCanvas::SetColour(const char *colour)
{
  if (m_glContext)
    m_glContext->SetColour(colour);
}

// TODO: Have to have this called by parent frame (?)
// So we need wxFrame to call OnQueryNewPalette for all children...
void wxGLCanvas::OnQueryNewPalette(wxQueryNewPaletteEvent& event)
{
	/* realize palette if this is the current window */
	if (m_glContext && m_glContext->GetPalette()->Ok()) {
	    ::UnrealizeObject((HPALETTE) m_glContext->GetPalette()->GetHPALETTE());
	    ::SelectPalette((HDC) m_glContext->GetHDC(), (HPALETTE) m_glContext->GetPalette()->GetHPALETTE(), FALSE);
	    ::RealizePalette((HDC) m_glContext->GetHDC());
	    Refresh();
	    event.SetPaletteRealized(TRUE);
    }
    else
	    event.SetPaletteRealized(FALSE);
}

// I think this doesn't have to be propagated to child windows.
void wxGLCanvas::OnPaletteChanged(wxPaletteChangedEvent& event)
{
	/* realize palette if this is *not* the current window */
	if ( m_glContext &&
         m_glContext->GetPalette() &&
         m_glContext->GetPalette()->Ok() &&
         (this != event.GetChangedWindow()) )
    {
	    ::UnrealizeObject((HPALETTE) m_glContext->GetPalette()->GetHPALETTE());
	    ::SelectPalette((HDC) m_glContext->GetHDC(), (HPALETTE) m_glContext->GetPalette()->GetHPALETTE(), FALSE);
	    ::RealizePalette((HDC) m_glContext->GetHDC());
	    Refresh();
	}
}

/* Give extensions proper function names. */

/* EXT_vertex_array */
void glArrayElementEXT(GLint i)
{
}

void glColorPointerEXT(GLint size, GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer)
{
}

void glDrawArraysEXT(GLenum mode, GLint first, GLsizei count)
{
#ifdef GL_EXT_vertex_array
    static PFNGLDRAWARRAYSEXTPROC proc = 0;

    if ( !proc )
    {
        proc = (PFNGLDRAWARRAYSEXTPROC) wglGetProcAddress("glDrawArraysEXT");
    }

    if ( proc )
        (* proc) (mode, first, count);
#endif
}

void glEdgeFlagPointerEXT(GLsizei stride, GLsizei count, const GLboolean *pointer)
{
}

void glGetPointervEXT(GLenum pname, GLvoid* *params)
{
}

void glIndexPointerEXT(GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer)
{
}

void glNormalPointerEXT(GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer)
{
#ifdef GL_EXT_vertex_array
    static PFNGLNORMALPOINTEREXTPROC proc = 0;

    if ( !proc )
    {
        proc = (PFNGLNORMALPOINTEREXTPROC) wglGetProcAddress("glNormalPointerEXT");
    }

    if ( proc )
        (* proc) (type, stride, count, pointer);
#endif
}

void glTexCoordPointerEXT(GLint size, GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer)
{
}

void glVertexPointerEXT(GLint size, GLenum type, GLsizei stride, GLsizei count, const GLvoid *pointer)
{
#ifdef GL_EXT_vertex_array
    static PFNGLVERTEXPOINTEREXTPROC proc = 0;

    if ( !proc )
    {
        proc = (PFNGLVERTEXPOINTEREXTPROC) wglGetProcAddress("glVertexPointerEXT");
    }

    if ( proc )
        (* proc) (size, type, stride, count, pointer);
#endif
}

/* EXT_color_subtable */
void glColorSubtableEXT(GLenum target, GLsizei start, GLsizei count, GLenum format, GLenum type, const GLvoid *table)
{
}

/* EXT_color_table */
void glColorTableEXT(GLenum target, GLenum internalformat, GLsizei width, GLenum format, GLenum type, const GLvoid *table)
{
}

void glCopyColorTableEXT(GLenum target, GLenum internalformat, GLint x, GLint y, GLsizei width)
{
}

void glGetColorTableEXT(GLenum target, GLenum format, GLenum type, GLvoid *table)
{
}

void glGetColorTableParamaterfvEXT(GLenum target, GLenum pname, GLfloat *params)
{
}

void glGetColorTavleParameterivEXT(GLenum target, GLenum pname, GLint *params)
{
}

/* SGI_compiled_vertex_array */
void glLockArraysSGI(GLint first, GLsizei count)
{
}

void glUnlockArraysSGI()
{
}


/* SGI_cull_vertex */
void glCullParameterdvSGI(GLenum pname, GLdouble* params)
{
}

void glCullParameterfvSGI(GLenum pname, GLfloat* params)
{
}

/* SGI_index_func */
void glIndexFuncSGI(GLenum func, GLclampf ref)
{
}

/* SGI_index_material */
void glIndexMaterialSGI(GLenum face, GLenum mode)
{
}

/* WIN_swap_hint */
void glAddSwapHintRectWin(GLint x, GLint y, GLsizei width, GLsizei height)
{
}