SMemDC.cpp

#include "souistd.h"
#include "helper/SMemDC.h"
SNSBEGIN
 
SMemDC::SMemDC()
    : m_bBmpOwner(FALSE)
    , m_bHasBitmap(FALSE)
    , m_hOldBmp(NULL)
    , m_hDC(NULL)
{
}
 
SMemDC::SMemDC(HDC hdc, const CRect &rc)
    : m_bBmpOwner(FALSE)
    , m_bHasBitmap(FALSE)
    , m_hOldBmp(NULL)
{
    InitDC(hdc, rc);
}
 
SMemDC::SMemDC(HDC hdc, HBITMAP hBmp)
    : m_bBmpOwner(FALSE)
    , m_bHasBitmap(TRUE)
{
    m_hDC = CreateCompatibleDC(hdc);
    SASSERT(m_hDC != NULL);
    if (hBmp)
        m_hOldBmp = (HBITMAP)::SelectObject(m_hDC, hBmp);
    else
        m_hOldBmp = NULL;
    ::SetViewportOrgEx(m_hDC, 0, 0, NULL);
}
 
SMemDC::~SMemDC(void)
{
    DeleteDC();
}
 
HBITMAP SMemDC::SelectBitmap(HBITMAP hBmp)
{
    SASSERT(m_hDC);
    if (hBmp)
    {
        m_hOldBmp = (HBITMAP)::SelectObject(m_hDC, hBmp);
        m_bBmpOwner = FALSE;
        m_bHasBitmap = TRUE;
        ::SetViewportOrgEx(m_hDC, 0, 0, NULL);
        return m_hOldBmp;
    }
    else if (m_bHasBitmap)
    {
        HBITMAP hBmp = (HBITMAP)::SelectObject(m_hDC, m_hOldBmp);
        m_hOldBmp = NULL;
        m_bBmpOwner = FALSE;
        m_bHasBitmap = FALSE;
        return hBmp;
    }
    else
    {
        return NULL;
    }
}
 
void SMemDC::DeleteDC()
{
    if (m_hDC && m_hOldBmp)
    {
        HBITMAP hBmp = (HBITMAP)::SelectObject(m_hDC, m_hOldBmp);
        if (m_bBmpOwner)
            DeleteObject(hBmp);
    }
    if (m_hDC)
        ::DeleteDC(m_hDC);
    m_bHasBitmap = FALSE;
    m_bBmpOwner = FALSE;
}
 
BOOL SMemDC::InitDC(HDC hdc, const CRect &rc)
{
    if (m_hDC)
        return FALSE;
    m_hDC = ::CreateCompatibleDC(hdc);
    if (!m_hDC)
        return FALSE;
    HBITMAP hBmp = CreateCompatibleBitmap(hdc, rc.Width(), rc.Height());
    if (!hBmp)
    {
        ::DeleteDC(m_hDC);
        return FALSE;
    }
    m_hOldBmp = (HBITMAP)SelectObject(m_hDC, hBmp);
    ::SetViewportOrgEx(m_hDC, -rc.left, -rc.top, NULL);
    m_bHasBitmap = TRUE;
    m_bBmpOwner = TRUE;
    return TRUE;
}
 
SNSEND