---

BitmapScreen.cpp

Go to the documentation of this file.

// BitmapScreen.cpp: implementation of the BitmapScreen class.


#include "stdafx.h"
#include "BitmapScreen.h"

// Construction

BitmapScreen::BitmapScreen(const int tlX, const int tlY, const int w, const int h)
: VScreen(tlX, tlY, w, h)
{
    currentBuffer = 0;
    buffer[0].createCompatible(w, h, 8);
    buffer[1].createCompatible(w, h, 8);

    writeMutex = CreateMutex(NULL, false, NULL);
}

// Member Functions

void BitmapScreen::paint(HDC hDC)
{
    currentBufferLock.WaitToRead();

    RECT regionR = VScreen::getRgnRect();

    SetDIBitsToDevice(
        hDC,
        regionR.left, regionR.top,
        buffer[currentBuffer].getPBITMAPINFOHEADER()->biWidth,
        abs(buffer[currentBuffer].getPBITMAPINFOHEADER()->biHeight),
        0, 0,
        0,
        abs(buffer[currentBuffer].getPBITMAPINFOHEADER()->biHeight),
        buffer[currentBuffer].getPBytes(),
        buffer[currentBuffer].getPBITMAPINFO(),
        DIB_RGB_COLORS);

    currentBufferLock.Done();
}

const DIBitmap* BitmapScreen::getReadBuffer()
{
    currentBufferLock.WaitToRead();
    return &buffer[currentBuffer];
}

void BitmapScreen::DoneReading()
{
    currentBufferLock.Done();
}

DIBitmap* BitmapScreen::getWriteBuffer()
{
    WaitForSingleObject(writeMutex, INFINITE);
    return &buffer[0 == currentBuffer ? 1 : 0];
}

bool BitmapScreen::DoneWriting()
{
    int otherBuffer = 0 == currentBuffer ? 1 : 0;
    
    if( abs(buffer[otherBuffer].getPBITMAPINFOHEADER()->biHeight) != abs(VScreen::getHeight())
            || buffer[otherBuffer].getPBITMAPINFOHEADER()->biWidth != VScreen::getWidth() ){
        assert( ReleaseMutex(writeMutex) );
        return false;
    }

    currentBufferLock.WaitToWrite();

    currentBuffer = otherBuffer;

    currentBufferLock.Done();

    assert( ReleaseMutex(writeMutex) );
    return true;
}

---