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diff --git a/Docs/USING-Framebuffer b/Docs/USING-Framebuffer new file mode 100644 index 000000000..e63d47ae2 --- /dev/null +++ b/Docs/USING-Framebuffer @@ -0,0 +1,181 @@ +-------------------------------------------------------------------------------- + Usage Instructions for Framebuffer NetSurf 2nd October 2010 +-------------------------------------------------------------------------------- + + This document provides usage instructions for the Framebuffer version of + NetSurf. + + Framebuffer NetSurf has been tested on Ubuntu and Debian. + +Overview +======== + + What it is + ---------- + + The NetSurf framebuffer front end is primarily intended for kiosk + and embedded applications where there is insufficient Operating + System support for a full graphical windowing environment. + + The framebuffer frontend features: + + * A trivial occluded rectangle window management toolkit + + * Font handling system using either: + - A trivial internal monochrome bitmap glyph set. + - An interface to fully anti-aliased glyphs using libfreetype 2 + + * Uses libnsfb to provide transparent support for: + - Numerous surface providers allowing usage on Linux, X, SDL, VNC + and any mapped linear memory region. + - Surface depths of 8, 16, 24 and 32bpp + - Optimised software plotters for lines, rectangles, polygons, + arbitrary ellipses (including circles), cubic and quadratic + splines, font glyphs and 32bpp RGBA bitmaps. + - Abstracted input handling. + + What it is not + -------------- + + The framebuffer frontend is not a replacement for full native + ports. It lacks functionality and flexibility compared to such + implementations. + + Limitations include: + - Single window interface. + - No tabbed interface. + - Expects to control the entire plotting surface. + - No ability to re-size a surface after initialisation. + - Inflexible input character mapping. + - Limited history view. + + In addition it should be noted support for some libnsfb surfaces has + been implemented purely for debugging functionality (SDL + especially) and is not intended to replace native surface + handlers. + + If a high level windowing system is available then a native NetSurf + frontend is almost certainly a better choice than attempting to use + the framebuffer frontend. + + If there is a graphical environment which supports GTK then using + the GTK frontend is a vastly superior choice. The framebuffer + frontend will appear exceptionally limited on such capable systems. + + +Configuring +=========== + + Several resources are set at *compile* time and are not changeable at + run time such as the icon bitmaps, the font system to use and what + default surface to use. Refer to the BUILDING-Framebuffer document + for details. + + Toolkit Options + --------------- + + The trivial toolkit has some configuration parameters allowing the + user to alter specific aspects of the UI. All the sizes are in + surface pixels however that is mapped. + + fb_furniture_size + This is the size allowed for the scroll bar elements. + + fb_toolbar_size + The height of the toolbar. + + fb_toolbar_layout + The layout of the toolbar, layout uses a string to define buttons + type and position each character adds an element to the toolbar: + + b - back + l - local history + f - forward + s - stop + r - refresh + u - url bar expands to fit remaining space + t - throbber/activity indicator + c - close the current window + + The default layout is "blfsrut" there should be no more than a + single url bar entry. If the option is set to the empty string (no + spaces permitted) the toolbar is disabled altogether. + + fb_osk + Whether the on screen keyboard should be enabled for input. + + + Framebuffer Surface + ------------------- + + There are four command line switches which override compiled in + defaults these are: + + -f <handler> + Selects a surface handler to pass to libnsfb instead of the + default. (e.g. x, sdl, mem, linux) + + -b <depth> + Selects the pixel depth to pass to libnsfb instead of the + compiled in default. (one of 8, 16, 24, 32) + + -w <width> + Selects the surface width to pass to libnsfb instead of the + compiled in default. + + -h <height> + Selects the surface height to pass to libnsfb instead of the + compiled in default. + + As with any NetSurf frontend run-time configuration is read from a + "Choices-fb" file. This file is a simple key:value list. In addition + to the standard values supported by the NetSurf core there are a + number of values to control specific aspects of the framebuffer + version. + + The libnsfb surface parameters are controlled with: + + fb_refresh - The refresh rate (for physical displays) + fb_depth - The depth (in bits per pixel) of the surface + fb_device - The path to the device (for physical displays) + fb_input_devpath - The path to the input devices (for linux input layer) + fb_input_glob - The input device selection glob (for linux input layer) + window_width - The width of the framebuffer + window_height - The height of the framebuffer + + The defaults are for 800 by 600 pixels at 16bpp and 70Hz refresh rate. + + The documentation of libnsfb should be consulted for further + information about supported surfaces and their configuration. + + Fonts + ----- + + If the compile time option is set to use the freetype font system + then several configuration options are available. If the simple + bitmap glyphs are used none of these options apply. + + The font glyphs are, by default, rendered as 256 level transparency + which gives excellent visual results even on small font sizes. + + The default font is the Vera truetype font set. The default path they + are sourced from is /usr/share/fonts/truetype/ttf-bitstream-vera/ . + + The font selection may be changed by placing truetype font files + in the resources path. The resource files will be the generic names + sans_serif.ttf, sans_serif_bold.ttf etc. The selection may also be + overridden by setting options. + + The font system is configured at run-time by several options. The + fb_font_monochrome option causes the renderer to use monochrome + glyph rendering which is faster to plot but slower to render and + much less visually appealing. The remaining seven options control + the files to be used for font faces. + + fb_face_sans_serif - The sans serif face + fb_face_sans_serif_bold - The bold sans serif face + fb_face_sans_serif_italic - The italic sans serif face + fb_face_sans_serif_italic_bold - The bold italic sans serif face. + fb_face_monospace - The monospaced font + fb_face_serif - The serif font + fb_serif_bold - The bold serif font |