// Wild Magic Source Code
// David Eberly
// http://www.geometrictools.com
// Copyright (c) 1998-2008
//
// This library is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation; either version 2.1 of the License, or (at
// your option) any later version.  The license is available for reading at
// either of the locations:
//     http://www.gnu.org/copyleft/lgpl.html
//     http://www.geometrictools.com/License/WildMagicLicense.pdf
//
// Version: 4.0.1 (2006/07/25)

#include "Wm4OpenGLRendererPCH.h"
#include "Wm4WglRenderer.h"
using namespace Wm4;

//----------------------------------------------------------------------------
WglRenderer::WglRenderer (HWND hWnd, FrameBuffer::FormatType eFormat,
    FrameBuffer::DepthType eDepth, FrameBuffer::StencilType eStencil,
    FrameBuffer::BufferingType eBuffering,
    FrameBuffer::MultisamplingType eMultisampling, int iWidth, int iHeight,
    int iPixelFormat)
    :
    OpenGLRenderer(eFormat,eDepth,eStencil,eBuffering,eMultisampling,iWidth,
        iHeight)
{
    assert(m_iWidth > 0 && m_iHeight > 0);
    m_iSaveWidth = m_iWidth;
    m_iSaveHeight = m_iHeight;

    m_hWnd = hWnd;
    m_hWindowDC = ::GetDC(m_hWnd);

    // select format for drawing surface
    PIXELFORMATDESCRIPTOR kPFD;
    memset(&kPFD,0,sizeof(PIXELFORMATDESCRIPTOR));
    kPFD.nSize = sizeof(PIXELFORMATDESCRIPTOR);
    kPFD.nVersion = 1;
    kPFD.dwFlags =
        PFD_DRAW_TO_WINDOW |
        PFD_SUPPORT_OPENGL |
        PFD_GENERIC_ACCELERATED;
    if (m_eBuffering == FrameBuffer::BT_BUFFERED_DOUBLE)
    {
        kPFD.dwFlags |= PFD_DOUBLEBUFFER;
    }

    // m_kBufferParams.Format is ignored, always create 32-bit RGBA buffer
    kPFD.iPixelType = PFD_TYPE_RGBA;
    kPFD.cColorBits = 32;

    switch (m_eDepth)
    {
    case FrameBuffer::DT_DEPTH_NONE:  kPFD.cDepthBits =  0;  break;
    case FrameBuffer::DT_DEPTH_16:    kPFD.cDepthBits = 16;  break;
    case FrameBuffer::DT_DEPTH_24:    kPFD.cDepthBits = 24;  break;
    case FrameBuffer::DT_DEPTH_32:    kPFD.cDepthBits = 32;  break;
    default:                          kPFD.cDepthBits = 16;  break;
    }

    if (m_eStencil == FrameBuffer::ST_STENCIL_8)
    {
        kPFD.cStencilBits = 8;
    }
    else
    {
        kPFD.cStencilBits = 0;
    }

    // set the pixel format for the rendering context
    bool bFirstTime = (iPixelFormat == 0 ? true : false);
    if (bFirstTime)
    {
        // First time creation.  If multisampling is requested, a second
        // creation will occur and the input pixel format will be supplied
        // directly to SetPixelFormat.
        iPixelFormat = ChoosePixelFormat(m_hWindowDC,&kPFD);
        if (iPixelFormat == 0)
        {
            return;
        }
    }

    BOOL bSuccess = SetPixelFormat(m_hWindowDC,iPixelFormat,&kPFD);
    if (!bSuccess)
    {
        assert(false);
        return;
    }

    // create an OpenGL context
    m_hWindowRC = wglCreateContext(m_hWindowDC);
    if (!m_hWindowRC)
    {
        assert(false);
        return;
    }

    bSuccess = wglMakeCurrent(m_hWindowDC,m_hWindowRC);
    if (!bSuccess)
    {
        assert(false);
        return;
    }

    if (bFirstTime)
    {
        // Load the function pointers for the OpenGL extensions.  This only
        // needs to occur once.  If you want a file to be created that stores
        // the OpenGL driver information, change the input filename to a
        // valid string; for example, "OpenGLDriverInfo.txt".
        const char* acInfoFile = "OpenGLDriverInfo.txt";
        GTInitWGL(acInfoFile);
    }

    // disable the wait for vertical sync
    wglSwapIntervalEXT(0);

    // use the system font as default
    DisplayListInfo kInfo;
    int iFirstChar = int(' ');
    kInfo.Quantity = 127 - iFirstChar;
    kInfo.Start = glGenLists(kInfo.Quantity) ;
    kInfo.Base = kInfo.Start - iFirstChar;
    m_kDLInfo.push_back(kInfo);
    m_hOldFont = SelectObject(m_hWindowDC,GetStockObject(SYSTEM_FONT)); 
    wglUseFontBitmaps(m_hWindowDC,iFirstChar,kInfo.Quantity,kInfo.Start);

    InitializeState();
}
//----------------------------------------------------------------------------
WglRenderer::~WglRenderer ()
{
    for (int i = 0; i < (int)m_kDLInfo.size(); i++)
    {
        DisplayListInfo kInfo = m_kDLInfo[i];
        glDeleteLists(kInfo.Start,kInfo.Quantity);
    }

    if (m_hWindowRC)
    {
        wglDeleteContext(m_hWindowRC);
    }

    if (m_hWindowDC)
    {
        SelectObject(m_hWindowDC,m_hOldFont);
        ReleaseDC(m_hWnd,m_hWindowDC);
    }
}
//----------------------------------------------------------------------------
void WglRenderer::Activate ()
{
    if (wglGetCurrentContext() != m_hWindowRC)
    {
        wglMakeCurrent(m_hWindowDC,m_hWindowRC);
        OpenGLRenderer::Activate();
    }
}
//----------------------------------------------------------------------------
bool WglRenderer::IsActive () const
{
    return wglGetCurrentContext() == m_hWindowRC;
}
//----------------------------------------------------------------------------
void WglRenderer::ToggleFullscreen ()
{
    OpenGLRenderer::ToggleFullscreen();
    glFinish();

    DWORD dwStyle = WS_OVERLAPPEDWINDOW | WS_CLIPSIBLINGS | WS_CLIPCHILDREN;

    UINT uiFlags = SWP_NOACTIVATE | SWP_NOOWNERZORDER |
        SWP_NOSENDCHANGING | SWP_NOZORDER;

    RECT kRect;

    if (m_bFullscreen)
    {
        m_iSaveWidth = m_iWidth;
        m_iSaveHeight = m_iHeight;
        GetWindowRect(GetDesktopWindow(),&kRect);
        AdjustWindowRect(&kRect,dwStyle,FALSE);
    }
    else
    {
        m_iWidth = m_iSaveWidth;
        m_iHeight = m_iSaveHeight;

        kRect.left = 0;
        kRect.top = 0;
        kRect.right = m_iWidth-1;
        kRect.bottom = m_iHeight-1;
        AdjustWindowRect(&kRect,dwStyle,FALSE);

        kRect.right -= kRect.left;
        kRect.left = 0;
        kRect.bottom -= kRect.top;
        kRect.top = 0;
    }

    SetWindowPos(m_hWnd,HWND_TOP,kRect.left,kRect.top,
        kRect.right-kRect.left,kRect.bottom-kRect.top,uiFlags);
}
//----------------------------------------------------------------------------
bool WglRenderer::BeginScene ()
{
    return wglGetCurrentContext() == m_hWindowRC;
}
//----------------------------------------------------------------------------
void WglRenderer::DisplayBackBuffer ()
{
    SwapBuffers(m_hWindowDC);
}
//----------------------------------------------------------------------------
int WglRenderer::LoadFont (const char* acFace, int iSize, bool bBold,
    bool bItalic)
{
    int iWeight = (bBold ? FW_BOLD : FW_REGULAR);
        
    HFONT hFont = CreateFont(iSize,0,0,0,iWeight,(DWORD)bItalic,FALSE,
        FALSE,DEFAULT_CHARSET,OUT_DEFAULT_PRECIS,CLIP_DEFAULT_PRECIS,
        ANTIALIASED_QUALITY,VARIABLE_PITCH,acFace);
    
    if (!hFont)
    {
        assert(false);
        return -1;
    }

    DisplayListInfo kInfo;
    int iFirstChar = int(' ');
    kInfo.Quantity = 127 - iFirstChar;
    kInfo.Start = glGenLists(kInfo.Quantity) ;
    kInfo.Base = kInfo.Start - iFirstChar;
    m_kDLInfo.push_back(kInfo);
    SelectObject(m_hWindowDC,hFont); 
    wglUseFontBitmaps(m_hWindowDC,iFirstChar,kInfo.Quantity,kInfo.Start);
    DeleteObject(hFont);

    return (int)m_kDLInfo.size() - 1;
}
//----------------------------------------------------------------------------
void WglRenderer::SaveContext ()
{
    m_hSaveDC = wglGetCurrentDC();
    m_hSaveRC = wglGetCurrentContext();
}
//----------------------------------------------------------------------------
void WglRenderer::RestoreContext ()
{
    wglMakeCurrent(m_hSaveDC,m_hSaveRC);
}
//----------------------------------------------------------------------------
