如何对图片进行放大或缩小

2009-06-15 02:28:23 219 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

flex实现图片根据鼠标的滚动放大或缩小（以鼠标的的位置为中心放大缩小）第一步： var imageCanvas:ImageView = new ImageView();//创建ImageView对象 imageCanvas.img.source="tuzhi/1.jpg";//指定要显示的图片路径第二步：ImageView.mxml文件--->此类是主要方法 <mx:Canvas xmlns:mx="http://www.ado 阅读详情

我有一个函数,功能是显示程序里用到的画图,现在需要加一个放大或是缩小功能,没做过这方面的,没思路了,有谁做个吗,大家讨论下吧,



_VOID Canvas_Flip(_HANDLE hCanvas, _INT nX, _INT nY, _INT nWidth, _INT nHeight)

{

	HDC	hDC = (HDC)::SendMessage(SimulatorData.m_hMainFrame, UM_GetDrawDevices, NULL, NULL);

	_CANVASOBJECT*	pCanvas = (_CANVASOBJECT*)hCanvas;

	if (hDC && pCanvas)

	{

		_RECT	rect;

		GetScreenRect(&rect);

		

		if ((MediaPlayerRect.nWidth <= 0) || (MediaPlayerRect.nHeight <= 0))

			BitBlt(hDC, rect.nLeft + nX, rect.nTop + nY, nWidth, nHeight, pCanvas->hMemDC, nX, nY, SRCCOPY);

		else

		{



			_INT	x1 = nX, x2 = MediaPlayerRect.nLeft, x3 = MediaPlayerRect.nLeft + MediaPlayerRect.nWidth, x4 = nX + nWidth;

			_INT	y1 = nY, y2 = MediaPlayerRect.nTop, y3 = MediaPlayerRect.nTop + MediaPlayerRect.nHeight, y4 = nY + nHeight;

			if (x4 > x1 > 0 && y2 > y1)

				BitBlt(hDC, rect.nLeft + x1, rect.nTop + y1, x4 - x1, y2 - y1, pCanvas->hMemDC, x1, y1, SRCCOPY);

			if (x2 > x1 > 0 && y3 > y2)

				BitBlt(hDC, rect.nLeft + x1, rect.nTop + y2, x2 - x1, y3 - y2, pCanvas->hMemDC, x1, y2, SRCCOPY);

			if (x4 > x3 > 0 && y3 > y2)

				BitBlt(hDC, rect.nLeft + x3, rect.nTop + y2, x4 - x3, y3 - y2, pCanvas->hMemDC, x3, y2, SRCCOPY);

			if (x4 > x1 > 0 && y4 > y3)

				BitBlt(hDC, rect.nLeft + x1, rect.nTop + y3, x4 - x1, y4 - y3, pCanvas->hMemDC, x1, y3, SRCCOPY);

					}



	}

	::SendMessage(SimulatorData.m_hMainFrame, UM_ReleaseDrawDevices, (WPARAM)hDC, NULL);

}