OpenGL是一个工业标准的三维计算机图形软件接口,用户可方便地利用它来创建出高质量的三维彩色图像,并可对其作各种特殊处理。本文从计算机图学角度出发,重点分析投影交换中的透视投影变换原理和方法,并通过关例,对OpenGL中不同投影变换进行了说明。
1 概述 随着计算机的普及,越来越多的人开始学习并运用计算机。很多人学习计算机就是从学习输入汉字开始的,用五笔字型输入法或者用拼音输入法。由于汉字的复杂性,使得其输入远比字母输入困难。可以说,汉字的输入是一项十分繁琐的工作,对于文秘人员更是如此。 现在不用键盘也能输入汉字,而且,在一定条件下,比用键盘输入要快数十、甚至数百倍,这就是文字识别技术(OCR)。 我们已经知道,扫描仪可以把照片上的图形输
南疆棉区高产栽培技术模式下的陆地棉的干物质积累呈”S”型曲线增长 ;高产棉花总积累的干物质为 1 1 8.7克 /株 ;干物质增长最快的时期在 2 /8~ 1 2 /8(出苗后 85~ 95天 )。地上部干物质分配中心随生育进程发生着如下动态转移 :真叶→茎枝→蕾花→幼铃→铃壳→籽棉。棉铃内部的干物质分配、运输转移随时间及节位的变化呈现出有规律的变化
现代教育更加注重个体化教学和终身教育 ,随着网络的日益普及 ,网上教学的作用已越来越显著 .远程教学需要更多的个体化教学软件 ,作者从《微机原理及应用》课程特点及教改实践的分析入手 ,探讨了该课程教学软件的设计思想、结构特点及相关制作方法 .
Ten rainfall and irrigation water-collecting posts were set up in different ecotype districts of JiangxiProvince, China, to quarterly measure S content in rainfall and irrigation water. A rainwater ch
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