book_text17.htm

深入编程内幕vc++ 非常适合处学者学习

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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">位图显示的必要条件：</SPAN><SPAN 
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            API</SPAN><SPAN 
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            SetDIBitsToDevice(hdc，uXDest</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'; mso-shading: white; mso-pattern: gray-15 auto">，</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'; mso-shading: white; mso-pattern: gray-15 auto">，</SPAN><SPAN 
            lang=EN-US 
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            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'; mso-shading: white; mso-pattern: gray-15 auto">，<SPAN 
            lang=EN-US><O:P> </O:P></SPAN></SPAN></P>
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            lang=EN-US 
            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'; mso-shading: white; mso-pattern: gray-15 auto">uStartScan</SPAN><SPAN 
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            lang=EN-US 
            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'; mso-shading: white; mso-pattern: gray-15 auto">cScanLines</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'; mso-shading: white; mso-pattern: gray-15 auto">，</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'; mso-shading: white; mso-pattern: gray-15 auto">lpvBits</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'; mso-shading: white; mso-pattern: gray-15 auto">lpbmi</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'; mso-shading: white; mso-pattern: gray-15 auto">，</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; BACKGROUND: #d9d9d9; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'; mso-shading: white; mso-pattern: gray-15 auto">fuColorUse)<O:P> 
            </O:P></SPAN></P>
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">请查看这个函数的第十、十一个参数</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">lpvBits,lpbmi</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">。其中</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">lpvBits</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">指明了指向内存中</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">BMP</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">数据的地址，</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">lpbmi</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">指向一个</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">BITMAPINFO</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">的数据结构，只要有了这两个参数，一个</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">BMP</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">位图就被确定了。大家可以看到绝大多数的</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">Windows</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">图形图像浏览软件所能分析的文件格式，例如</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">jpg</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">gif</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">pcx</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">tif</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">等等，都是先在内存中建一个数据缓冲区，再根据图形图像格式建立一个<SPAN 
            lang=EN-US>BITMAPINFO的数据结构，再利用</SPAN></SPAN><SPAN lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">SetDIBitsToDevice</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">函数写到屏幕上。我们下面几个实例，也基本上采用这个方式。<SPAN 
            lang=EN-US><O:P> </O:P></SPAN></SPAN></P>
            <P class=MsoNormal 
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            style="FONT-SIZE: 12pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">&nbsp;<O:P> 
            </O:P></SPAN></P>
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            style="mso-bidi-font-weight: normal"><SPAN lang=EN-US 
            style="FONT-SIZE: 12pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">Windows</SPAN><SPAN 
            style="FONT-SIZE: 12pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">的调色板</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 12pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'"><O:P> 
            </O:P></SPAN></B></P>
            <P class=MsoNormal 
            style="WORD-BREAK: break-all; TEXT-INDENT: 20pt; mso-line-height-alt: 1.3pt; mso-pagination: none; mso-layout-grid-align: none; punctuation-wrap: simple"><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">Windows</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">的显示设备可以显示出成千上万种颜色，但是，在同一个屏幕上能同时显示的颜色数并不是成千上万种，我们把显示设备分为单色、十六色、二百五十六色、增强色、真彩色，或者是按照显示位区分成</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">1bit</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">，</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">4bit</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">，</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'">8bit</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; LAYOUT-GRID-MODE: line; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">，</SPAN><SPAN