DoAspectAdapt.cpp

DoAspectAdapt.cpp

enum ASPECT_MODE
{
    ASPECT_MODE_IGNORE,
    ASPECT_MODE_FIT,
    ASPECT_MODE_TRIM
};

BOOL DoAspectAdapt(ASPECT_MODE mode, const SIZE *psizSrc,
                   const RECT *prcScreen, RECT *prcFrame)
{
    BOOL ret = TRUE;
    INT cx, cy, cxScreen, cyScreen, cxFrame, cyFrame;

    switch (mode)
    {
    case ASPECT_MODE_IGNORE:
        *prcFrame = *prcScreen;
        return ret;

    case ASPECT_MODE_FIT:
        cx = psizSrc->cx;
        if (cx <= 0)
        {
            cx = 1;
            ret = FALSE;
        }
        cy = psizSrc->cy;
        if (cy <= 0)
        {
            cy = 1;
            ret = FALSE;
        }

        cxScreen = prcScreen->right - prcScreen->left;
        cyScreen = prcScreen->bottom - prcScreen->top;
        if (cxScreen * cy < cx * cyScreen)
        {
            cxFrame = cxScreen;
            cyFrame = cxScreen * cy / cx;
        }
        else
        {
            cyFrame = cyScreen;
            cxFrame = cyScreen * cx / cy;
        }

        prcFrame->left = (prcScreen->left + prcScreen->right - cxFrame) / 2;
        prcFrame->top = (prcScreen->top + prcScreen->bottom - cyFrame) / 2;
        prcFrame->right = prcFrame->left + cxFrame;
        prcFrame->bottom = prcFrame->top + cyFrame;

        return ret;

    case ASPECT_MODE_TRIM
        cx = psizSrc->cx;
        if (cx <= 0)
        {
            cx = 1;
            ret = FALSE;
        }
        cy = psizSrc->cy;
        if (cy <= 0)
        {
            cy = 1;
            ret = FALSE;
        }

        cxScreen = prcScreen->right - prcScreen->left;
        cyScreen = prcScreen->bottom - prcScreen->top;
        if (cxScreen * cy < cx * cyScreen)
        {
            cyFrame = cyScreen;
            cxFrame = cyScreen * cx / cy;
        }
        else
        {
            cxFrame = cxScreen;
            cyFrame = cxScreen * cy / cx;
        }

        prcFrame->left = (prcScreen->left + prcScreen->right - cxFrame) / 2;
        prcFrame->top = (prcScreen->top + prcScreen->bottom - cyFrame) / 2;
        prcFrame->right = prcFrame->left + cxFrame;
        prcFrame->bottom = prcFrame->top + cyFrame;
        return ret;

    default:
        return FALSE;
    }
}