Vector Graphics vs Raster Graphics

This is a lead-in to an up-coming series having to do with OpenOffice Draw which is capable of vector graphics. What most people are used to seeing are bit-mapped graphics such as a photo. Vector images typically present a higher contrast in color transitions.

Advantages to this style of drawing over raster graphics:

• Vector-oriented images are more flexible than bit maps because they can be resized and stretched.

• Images stored as vectors look better on devices (monitors and printers) with higher resolutions.
• Bit-mapped images always appear the same regardless of a device’s resolution.
• Another advantage of vector graphics is that representations of images often require less memory than bit-mapped images do.
• Zooming in on vector images, the image remains smooth and does not anti-alias
• The parameters of objects can be later modified.
• Moving, scaling, rotating, filling etc. doesn’t degrade the quality of a drawing. Moreover, it is usual to specify the dimensions in device-independent units, which results in the best possible rasterization on raster devices.
• From a 3-D perspective, rendering shadows is also much more realistic with vector graphics, as shadows can be abstracted into the rays of light which form them. This allows for photo realistic images and renderings

Almost all sophisticated graphics systems, including CADD systems and animation software, use vector graphics.

In addition, many printers (PostScript printers, for example) use vector graphics. Fonts represented as vectors are called vector fonts, scalable fonts, object-oriented fonts, and outline fonts.

Note most output devices, including dot-matrix printers, laser printers, and display monitors, are raster devices (plotters are the notable exception). This means that all objects, even vector objects, must be translated into bit maps before being output. The difference between vector graphics and raster graphics, therefore, is that vector graphics are not translated into bit maps until the last possible moment, after all sizes and resolutions have been specified.

PostScript printers, for example, have a raster image processor (RIP) that performs the translation within the printer. In their vector form, therefore, graphics representations can potentially be output on any device, with any resolution, and at any size.

Computer displays are made up from small dots called pixels. The picture is built up from these dots. The smaller and closer the dots are together, the better the quality of the image but the bigger the file needed to store the data.

If the image is magnified it becomes grainy as the resolution of the eye enables it to pick out individual pixels.

Vector graphics files store the lines, shapes and colours that make up an image as mathematical formulae. Since these formulae can produce an image scalable to any size and detail the quality of the image is only determined by the resolution of the display. The file size of vector data generating the image stays the same.

Printing the image to paper will usually give a sharper, higher resolution output than printing it to the screen but can use exactly the same vector data file.

The size of the file generated will depend on the resolution required but the size of the vector file generating the bitmap/raster file will always remain the same.

Thus it is easy to convert from a vector file to a range of bitmap/raster file formats but it is very much more difficult to go in the opposite direction.  However, once the file is converted from the vector format it is likely to be bigger and it loses the advantages of scalability without losing resolution.

Editing will also lose the convenience of being able to work on individual parts of the picture as discrete objects.

Vector formats are not always appropriate in graphics work. For example, digital devices such as cameras and scanners produce raster graphics that are impractical to convert into vectors.

Some vector editors support animation, while others (e.g. Adobe Flash) are specifically geared towards producing animated graphics. Generally, vector graphics are more suitable for animation, though there are raster-based animation tools as well.

Vector editors are closely related to desktop publishing software such as Adobe InDesign or Scribus, which also usually include some vector drawing tools (usually less powerful than those in standalone vector editors). Modern vector editors are capable of, and often preferable for, designing unique documents (like flyers or brochures) of up to a few pages; it’s only for longer or more standardized documents that the page layout programs are more suitable.

3D computer graphics software such as Maya or Blender can also be thought of as an extension of the traditional 2D vector editors, and they share some common concepts and tools.

Open Office

What is OpenOffice?

OpenOffice.org is a collection of applications that work together closely to provide the features expected from a modern office suite.  The components available include:
Writer A word processor similar in look and feel to Microsoft Word and offering a comparable range of functions and tools. It also includes the ability to export Portable Document Format (PDF) files with no additional software, and can also function as a WYSIWYG editor for creating and editing web pages.
Calc A spreadsheet similar to Microsoft Excel with a roughly equivalent range of features. Calc provides a number of features not present in Excel, including a system which automatically defines series for graphing, based on the layout of the user’s data. Calc is also capable of writing spreadsheets directly as a PDF file.
Impress A presentation program similar to Microsoft PowerPoint. It can export presentations to Adobe Flash (SWF) files allowing them to be played on any computer with the Flash player installed. It also includes the ability to create PDF files, and the ability to read Microsoft PowerPoint’s .ppt format. Impress suffers from a lack of ready-made presentation designs. However, templates are readily available on the Internet.
Base A database program similar to Microsoft Access. Base allows the creation and manipulation of databases, and the building of forms and reports to provide easy access to data for end-users. As with Access, Base may be used as a front-end to a number of different database systems, including Access databases (JET), ODBC data sources and MySQL/PostgreSQL. Base became part of the suite starting with version 2.0. Native to the OpenOffice.org suite is an adaptation of HSQL. While ooBase can be a front-end for any of the databases listed, there is no need for any of them to be installed.
Draw A vector graphics editor comparable in features to early versions of CorelDRAW. It features versatile “connectors” between shapes, which are available in a range of line styles and facilitate building drawings such as flowcharts. It has similar features to Desktop publishing software such as Scribus and Microsoft Publisher.
Math A tool for creating and editing mathematical formulae, similar to Microsoft Equation Editor. Formulae can be embedded inside other OpenOffice.org documents, such as those created by Writer. It supports multiple fonts and can export to PDF.