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Links is an open source text and graphic web browser with a pull-down menu system.〔(Links home page )〕 It renders complex pages, has partial HTML 4.0 support (including tables and frames and support for multiple character sets such as UTF-8), supports color and monochrome terminals and allows horizontal scrolling. It is intended for users who want to retain many typical elements of graphical user interfaces (pop up windows, menus etc.) in a text-only environment. The original version of Links was developed by Mikuláš Patočka in the Czech Republic. His group, Twibright Labs, later developed version 2 of the Links browser, that displays graphics, renders fonts in different sizes (with spatial anti-aliasing) and supports JavaScript (up to version 2.1pre28). The resulting browser is very fast, but it does not display many pages as they were intended. The graphical mode works even on Unix systems without the X Window System or any other window environment, using either SVGALib or the framebuffer of the system's graphics card. ==Graphics stack== The graphics stack has several peculiarities unusual for a web browser. The fonts displayed by Links are not derived from the system, but compiled into the binary as grayscale bitmaps in Portable Network Graphics (PNG) format. This allows the browser to be one executable file independent of the system libraries. However this increases the size of the executable to about 5 MB. The fonts are anti-aliased without hinting and for small line pitch an artificial sharpening is employed to increase legibility. Subpixel sampling further increases legibility on LCD displays. This allowed Links to have anti-aliased fonts at a time when anti-aliased font libraries were uncommon. All graphic elements (images and text) are first converted from given gamma space (according to known or assumed gamma information in PNG, JPEG etc.) through known user gamma setting into a 48 bits per pixel photometrically linear space where they are resampled with bilinear resampling to the target size, possibly taking aspect ratio correction into account. Then the data are passed through high-performance restartable dithering engine which is used regardless of monitor bit depth, i.e., also for 24 bits per pixel colour. This Floyd-Steinberg dithering engine takes into account the gamma characteristics of the monitor and uses 768 KiB of dithering tables to avoid time expensive calculations. A technique similar to self-modifying code, function templates, is used to maximize the speed of the dithering engine without using assembly language optimization, which is non-portable. Images which are scaled down also use subpixel sampling on LCD to increase level of detail. The reason for this high quality processing is: provide proper realistic up and down sampling of images, and photorealistic display regardless of the monitor gamma, without colour fringing caused by 8-bit gamma correction built into the X server. It also increases the perceived colour depth over 24 bits per pixel. Despite the amount of digital image processing that has to be internally done, Links is one of the fastest graphical web browsers. Links has graphics drivers for the X Server, Linux framebuffer, svgalib, OS/2 PMShell and AtheOS GUI. This allows it to run in graphics mode even on platforms which don't have X Server. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Links (web browser)」の詳細全文を読む スポンサード リンク
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