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2006-08-04 05:39:16 111 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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调用D3D11硬解码和渲染VideoProcessor版本在https://blog.csdn.net/robothn/article/details/78781321一文中使用shader来显示FFMPEG硬解码后的YUV420P，本文调用D3D11的videoprocessor来进行图像空间变换和尺寸变换，取得了较好的效果。 1.初始化D3D11设备、videodevice等数据结构 FFMPEG调用D3D11硬解码，获取其对应的device，videodevice。。。 FFMPEG使用av_hwdevice_find_type_by_name调用D3d11 阅读详情

要把滚动条和鼠标上的滑轮联系起来怎么办啊?用代码怎么实现阿？VC

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从SPI协议到文件系统：手把手教你用HAL库给W25Q16移植FATFS（附扇区管理优化方案）本文详细介绍了如何在STM32平台上，通过HAL库的SPI接口为W25Q16 Flash芯片移植FATFS文件系统。文章从SPI通信基础讲起，深入解析了FATFS底层驱动（diskio.c）的移植要点，并重点探讨了针对W25Q16的4KB物理扇区特性进行扇区管理优化的两种方案，旨在帮助开发者构建稳定高效的文件存储方案。阅读详情

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y_shen 2006-08-04

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http://community.csdn.net/Expert/topic/4853/4853672.xml?temp=.6471063

truewill 2006-08-04

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The WM_MOUSEWHEEL message is sent to the focus window when the mouse wheel is rotated. The DefWindowProc function propagates the message to the window's parent. There should be no internal forwarding of the message, since DefWindowProc propagates it up the parent chain until it finds a window that processes it.

WM_MOUSEWHEEL
fwKeys = LOWORD(wParam); // key flags
zDelta = (short) HIWORD(wParam); // wheel rotation
xPos = (short) LOWORD(lParam); // horizontal position of pointer
yPos = (short) HIWORD(lParam); // vertical position of pointer

Parameters
fwKeys
Value of the low-order word of wParam. Indicates whether various virtual keys are down. This parameter can be any combination of the following values: Value Description
MK_CONTROL Set if the ctrl key is down.
MK_LBUTTON Set if the left mouse button is down.
MK_MBUTTON Set if the middle mouse button is down.
MK_RBUTTON Set if the right mouse button is down.
MK_SHIFT Set if the shift key is down.

zDelta
The value of the high-order word of wParam. Indicates the distance that the wheel is rotated, expressed in multiples or divisions of WHEEL_DELTA, which is 120. A positive value indicates that the wheel was rotated forward, away from the user; a negative value indicates that the wheel was rotated backward, toward the user.
xPos
Value of the low-order word of lParam. Specifies the x-coordinate of the pointer, relative to the upper-left corner of the screen.
yPos
Value of the high-order word of lParam. Specifies the y-coordinate of the pointer, relative to the upper-left corner of the screen.
Remarks
The zDelta parameter will be a multiple of WHEEL_DELTA, which is set at 120. This is the threshold for action to be taken, and one such action (for example, scrolling one increment) should occur for each delta.

The delta was set to 120 to allow Microsoft or other vendors to build finer-resolution wheels in the future, including perhaps a freely-rotating wheel with no notches. The expectation is that such a device would send more messages per rotation, but with a smaller value in each message. To support this possibility, you should either add the incoming delta values until WHEEL_DELTA is reached (so for a given delta-rotation you get the same response), or scroll partial lines in response to the more frequent messages. You could also choose your scroll granularity and accumulate deltas until it is reached.

truewill 2006-08-04

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WM_MOUSEWHEEL

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