Exercise 8

Vector Graphics is very popular on the internet. The reason is simple, small file sizes means faster downloads. In the commercial world time is money. What does Vector Graphics offer the PC user? That answer is flexibility. By combining vector and raster images some very unique effects are possible. The major usage for Vectors is in the creation of all types of art work including posters, greeting cards, and flyers. This exercise is intended to introduce the concepts and ideas associated with the Vector approach. Class time does not permit going into detail on the many uses of Vectors. The most obvious use lies in using Vector Text to label photographs.

Please bear with my artistic abilities as I attempt to demonstrate the Vector Graphics Concepts. You will not be able to recognize my example so let me call it a cat.

1. Start a PSP Application and open a new image with the following attributes:
    Size: 700 x 500 pixels
    Resolution: 72 pixels/inch
    Background Color: White
    Image Type: 16.7 Million Colors (24 Bit)

2. We will use this background as a sounding board to play and explore with Vector Objects. Select the "Draw a preset shape" tool from the tool bar (blue rectangle with a red ellipse). Now open the tool options menu and look at the choices. From the first tab select...
    Shape Type: ellipse
    Style: Stroked and Filled
    Line Width: 3
    Note: Be sure both antialias and create as a vector are checked.

3. Before we start to draw our cat we need to explore and draw various preset shapes with various attributes in order to become familiar with them. Shown below are some examples.

4. As you draw the shapes notice the ten "handles" or small "boxes" associated with each object. These are the object control points. Experiment with them, click and drag each one and notice the effects. What are the functions of the two controls in the center of the ellispe?

5. Now we will combine two objects by using the "vector object selection tool" (it is a tool button located next to the "Draw a preset shape" tool. Notice the information given on the The Status bar, located along the bottom of the Paint Shop Pro window when you position your mouse over this button (<shift> adds to the vector selection and <ctrl> removes from the vector selection). Hold down the shift key as you select different objects. This feature allows you to move and resize several objects at the same time.

1. Select and group some of your objects together. Right click inside of the group and notice the choices, click on properties. Can you change the line and fill colors of the selected group? Try it.

2. Select one of your objects then right click inside of it. Notice all of the choices, choose the "Properties" command. Change the name of this object. Change the line and fill styles, try various colors and line widths. Notice the effect caused when you uncheck the antialias box. You really have a wide control over all your vector objects. EXPERIMENT !

3. Notice the "Arrange" command on the properties menu. Select and move some of your objects such that they partially over lap each other. Can you then select one of them and move it in the vector object stack. Remember vector objects are each on a separate layer.

1. You need one more basic concept to allow you to create a simple object with Vectors. This is the ability to add nodes to an object. You may have already noticed the command for this, it is below the "properties" command when you get the menu by right clicking inside of a selected object. Choose this one, it is "Node Edit". Notice the change in the cursor and the disappearance of the selection box.

2. Use this new cursor to click and drag on a control point (The Control Points are now individual Nodes). To add nodes hold down the "Ctrl" key and move the pointer to a point on the object's curve where you want to add the new node. When you see the word "ADD" appear click the mouse. You may add points all along any object's line segments. Notice the new control points for the added node, they look like an arrow. Click on one of them and drag it. What happens to the line segment?

2. Now our understanding of the BASIC vector concept is established. We will put these ideas to work in an attempt to construct a vector cat. Start a new drawing with the same attributes as in b-1 above. Select the ellipse tool as in b-2. Below is shown one way to start a cat. Create a similar set of elliptical objects.

3. Add nodes and drag them to create ears, whiskers, and a tail. Fill your objects with color. Add objects for the eyes, nose, and mouth. You will never get your cat to be as ugly as mine. My idea of what a cat looks like is shown below. You now know why I am an instructor rather than a "Graphics Illustrator".

1. If you should ever want to change the appearance of your "Vector Cat" you need to save the image in a format that you can use in the future. One way is to save it as a psp or Paint Shop Pro image. When you open this in the PSP application you then have control over the various layers and objects.

2. When you save your image in other formats you lose the editing features. Your file size will however be smaller because you are not saving all of the overhead information associated with the various layers and individual vectors.

3. Meta and vector image formats can both contain vector information. Vector data is a set of instructions for recreation of shapes that form an image. These instructions are mathematical formulas that contain information about the location and characteristics of these shapes. Vector data cannot reproduce photo-realistic images, but for other types of images it has two advantages over raster data:

4. In the strictest definition, a vector format can only contain vector information. In common practice, many formats that are considered to be vector allow the user to include non-vector data, such as raster images or text. Meta formats explicitly allow more than just vector data. For example, a typical Windows metafile might contain a bitmap, vector information, and text, with the bitmap constituting the majority of the image, and the vector and text data providing annotation.

The following table lists the meta and vector formats that Paint Shop Pro Version 6.01 can open and save.

Format	Source/Standard	Open (Read )	Save (Write)
CDR	CorelDRAW!	Yes
CGM	Computer Graphics Metafile	Yes
CMX	Corel Clipart	Yes
DRW	Micrografx Draw	Yes
DXF	Autodesk	Yes
EMF	Windows Enhanced Metafile	Yes	Yes*
EPS	Encapsulated PostScript	Yes	Yes*
GEM	Ventura/GEM	Yes
HGL	Hewlett-Packard Graphics Language	Yes
PCT	Apple	Yes	Yes*
PIC	Lotus Development Corp.	Yes
WMF	Microsoft Windows Metafile	Yes	Yes*
WPG	WordPerfect	Yes	Yes*

A lot of material has been introduced in a relatively short time period. I sincerely hope that each of you will spend time with this CD outside of the computer classroom. Be patient with yourself, it takes considerable time to master these learning adventures. These Graphics Skills do snowball, the more time you spend with them the easier it becomes. If it did not require a lot of practice we would all be great Musicians. The same holds true for Graphic Illustrators. Whether you are a beginner or have considerable experience there is always something to be learned. Try not to rely on your memory, there is too much. Concentrate on the underlying principles, use experimentation as a learning device. Always remember any question you have may be answered by trying to do it. Do not allow yourself the luxury of frustration.

In the final lesson and exercise we will look briefly at animation and the creation of animated gifs. Belleive it or not, this ugly cat will wag it's tail.