ICT

Create graphics using basic graphic elements and edit predefined graphics.

sketch something on paper (a man or a house) and what you have is a piece of analog information. Changing what you draw can be easy or hard: you can erase pencil or charcoal marks easily enough, and you can scrape off oil paints and redo them with no trouble; but altering water colors or permanent markers, swapping colors or resizing your picture is more complicated.

that’s why it is more efficient to draw a picture on a computer screen and what you have is a piece of digital information (your picture is stored as a series of numbers). Change the numbers and you can change the picture, in the blink of an eye or even quicker. It’s easy to shift your picture around the screen, scale it up or down, rotate it, swap the colors, and transform it in all kinds of other ways. once it’s finished, you can save it, incorporate it into a text document, print it out, upload it to a web page, or email it to a client or work colleague, all because it’s digital information.

this is the use of a computer and specialized programs to produce and manipulate pictorial images.

the purpose of creating computer graphics is mainly for: Animation, business presentation and scientific research.

there are two very different ways of drawing digital images on a computer screen, known as raster and vector graphics.

A bitmap (or raster graphic) is a digital image composed of a matrix of dots. A bitmap graphic is composed of many tiny parts, called pixels, which are often many different colors. It is possible to edit each individual pixel.

When you take a photograph using a digital camera or scan an image from a magazine, you are creating a bitmap graphic.

since the computer has to store information about every single pixel in the image, the file size of a bitmap graphic is often quite large. When you resize a bitmap graphic, it tends to lose quality.

Vector graphics are graphics stored and drawn with instructions rather than grids of pixels. Vector images are mathematical calculations from one point to another that form lines and shapes. If you zoom into a vector graphic it will always look the same.

Resolution is the total number of pixels that make an image. In general, the more pixels used when capturing an image, the sharper the stored image is. this is called resolution, it is measured in dots per inch (dpi).

2-Dimensional computer graphics are mainly used in applications that were originally developed upon traditional printing and drawing technologies. In those applications, the two-dimensional image is not just a representation of a real-world object, but an independent artifact with added semantic value. two-dimensional (2D) models are therefore preferred because they give more direct control of the image than 3D computer graphics, whose approach is more akin (similar) to photography than to typography.

3D graphics, compared to 2D graphics, are graphics that use a three-dimensional representation of geometric data. For the purpose of performance, this is stored in the computer. this includes images that may be for later display or for real-time viewing.

·Modelling is the process of developing a mathematical representation of any three-dimensional surface (3D) of an object (either living or non-living) via specialized software. the product is called a 3D model.

·Rendering is the process of converting automatically 3Dwire frame models into 2D images with 3D photo realistic effects or non-photo realistic rendering on a computer.

·Animation is a process that uses computer generated images to create animated scenes. An animated scene starts with one picture, which is referred to a frame.

·Interaction is a technique of using a physical input/output device to perform a broad task in a human-computer dialogue.

Graphic images are stored digitally using a small number of standardized graphic file formats such as:

7.4 Areas of graphics use

Graphics are visual elements often used to point readers and viewers to particular information. they are also used to supplement text in an effort to aid readers in their understanding of a particular concept or make the concept more clear or interesting.

Graphics software are better at creating and manipulating bitmaps or vector graphics.

this software includes Microsoft Paint and Adobe Photoshop.

A paint program is a software graphics program that allows the user to draw or paint bit mapped images on a computer.

this is a professional software used in photography, design and video editing. It is a program that can edit images of any type. It was developed by Adobe systems. Photoshop is mainly a raster graphics editor. Photoshop is used in a similar way as Paint but in a more professional style. More information about Adobe is provided at the end of the unit.Vector graphics software

commonly used include: Adobe Illustrator, Adobe Free Hand, Corel Draw, Paint shop Pro.

Windows operating system comes with a basic, easy-to-use image creation program called Microsoft Paint which is a basic raster graphics program capable of creating, opening, and basic editing of image files, including BMP, JPG, GIF, and PNG. the default bitmap file type for Paint is BMP.

Follow these steps to open Ms Paint:

·Click the start button, all programs.

·From windows accessories, choose Paint.the following window appears.

When Paint launches, you’ll see a white “canvas” appear on the screen. Imagine this canvas as a piece of paper for you to draw or write on. You can adjust the size of the canvas before you start creating your masterpiece.

Using the already open paint program, you are going to locate and use the following tools;

Use an ellipse tool to create a basketball with a suitable background.

to get a round shape that has a black outline and an orange interior, use the following steps:

Step 1:Choose the ellipse tool.

Step 2:In the Fill options area, choose ▼ then select solid color. this will set foreground color for the outside, and set background color for the inside.

Step 3:Click the foreground Color box, and then click black to set the foreground color.

Step 4:Click the background Color box, and then click orange to set the background color.

Step 5:Click and hold the left mouse button and drag the mouse to form the oval.

Tip:to make it perfectly round, hold down the shift key as you drag the mouse.

Step 6:Use line tool.

    ·now choose the Line tool,

    ·then set size, and draw the vertical /horizontal lines, by dragging the mouse.

Tip:to make the lines perfectly straight, hold down the shift key as you drag.

Step 7:Curve tool.

 

       ·now, choose the Curve tool.

      ·Draw a straight line to the left of your vertical line.

      ·Click in the middle of the new line and drag it toward the vertical line to curve it.

IMPORTANT:to lock in the new shape, click on some other tool, like the selection tool.

       ·now, choose the Curve tool again.

       ·Draw a straight line to the right of your vertical line.

Step 8:Fill tool.

      ·now, go ahead and fill the white canvas with a different color.

     ·the Fill with color tool will flood a connected area with the color you choose.

     ·the final product should look something like this:

Step 9: save your work.

       ·From File menu, choose save as.

      ·From a dialog box, choose BMP picture.

·Choose the location where you want to save.

·type the name you wish to use (ball) make sure it will be saved as a 24 bit Bitmap – this will add .bmp to the filename for example: ball.bmp. We shall use this file later on

In order to use graphics features well, you should learn to select images or parts of the image to be affected/changed by the graphic feature. to select is to choose an option from two or more available options. Practice selecting image parts you may need to cut, copy or fill with color.

there are two different tools you can use to select parts of your image:

Free-form selection allows you to draw your own freehand selection line around an image, while the rectangular selection tool lets you draw a rectangle around an image.

Step 1:Click the arrow beneath the “Select” button.

Step 2:Choose “Rectangular” or “Free form.” see picture 7.9(a).

Step 3: to use either tool selected, start by clicking at the top left corner of your image, then hold down the mouse button as you trace your way around the image. then release the mouse.

Follow the steps given below to copy your image:

Step 1: select Image and make sure the image is highlighted with dotted rectangle.

Step 2:Copy the selected area by pressing Ctrl+C or click Copy command from the Home tab.

Step 3:Paste the image using Ctrl+V or Paste command on the Home tab.

Note: You can paste the copied selection in the same file in Paint or in other compatible programs, like Microsoft Word or Microsoft PowerPoint.If the image you want to copy has a background color that you don’t want to be a part of your selection, then:

Let us draw an image of a basketball net as shown below. By so doing we are to learn the following tools; copy and paste, move, resize, flip, skew, rotate, cutout, trim. these actions are repeated in this unit for purposes of learning more about paint in respective sections.

Follow steps 1 to 3 in section 7.7.2 to copy and paste the image. the results may appear as shown in picture 7.9(c).

Step 1: select the image to be moved.

Step 2:Click on the selection and drag to a new position. see picture 7.9(d), the pasted copy has been moved to lower left corner.

We are going to use original image and we resize it manually.Use the following steps to resize an image:

Step 1: select the image

Step 2:Click in any of the selection boxes and drag inwards (to reduce size) or drag outwards (to enlarge its size). see picture 7.9(e).

Note: You can also resize the image using the resize tool in the image group. This is covered later on in this unit.

Use the following steps to flip an image:

Step 1: select the image to be flipped.

Step 2:In the Image group click Rotate tool and then select Flip vertical or Flip horizontal. see picture 7.9(f), how the resized image is flipped horizontally.

Steps:Repeat steps 1 and 2 of part (d) above but instead of selecting a flipping option, select a rotate option e.g. Rotate right 90⁰. this task is repeated in other activities later in this book.

Step 1: select an image.

Step 2:Click Resize tool in the Image group.

Step 3:In the Resize and Skew dialog box, use section down for skew and type in Degrees for skewing the image.

Step 1: select a part of the image you want to cut-out or trim.

Step 2:Press delete key on keyboard.

a) Draw the shape of a heart and fill it with red color.

b) Move the shape to the left side on the page.

c) Copy and paste any half of the shape and move the pasted copy on the right side of the page.

d) type a Green bold text of font size 26 in the pasted copy as “Divided heart” and “one Heart” text in the original image.

e) erase a small part of the original shape that you want.

f) Apply a suitable background to the shapes and save your file as ‘our Hearts’.

to add text, follow the steps given below:

      

Follow the steps given below;

Note: Like other tools, you can adjust the width of the eraser with the Size menu.

to create and edit or reshape vector graphics suitably requires you to use a vector graphics software such as Adobe Illustrator, Adobe Freehand or Corel Draw. You can also introduce a Raster graphic into a vector graphics software and edit by converting it to vector graphic. For our case we use Adobe Illustrator. With Adobe Illustrator, you can design logos, t-shirt design, posters and flyers as vector graphics.

(b)a) Using Adobe Illustrator, create the following vector graphics or shapes as they appear and save the project as Better shapes.

b) Reshape or edit the graphics drawn in (a) above to appear as shown below

Step 1: open Adobe Illustrator, a vector graphics software. the window for Adobe Illustrator appears below.

Step 2:Click on File menu and select ‘New’ button to get a new document dialog box (shown below). name your file as My Shapes.

Step 3: start creating the shapes using various tools

to create the square:click the Rectangle Tool on the toolbox and then drag in the white background to draw the square.

to draw other shapes, click on white graphic near the rectangle tool to display other shape tools. then click on the ellipse tool to draw the circle/oval shape and afterwards click on the rounded rectangle tool to draw the rounded rectangle.

Step 4:Fill the square with green; the circle with gradient fill and rounded rectangle with brown color and increase on its shape outline.

to fill green color in the square, select the square using the selection tool, click where there is green color on the CMYK spectrum on the right of the window (or from alternative color button on toolbar).

to fill gradient in the circle/oval, select the circle and then click on the gradient button.

to fill the rounded rectangle with brown color, select it first, then click on the alternative color button on the toolbar.

Increase the outline of the rectangle by increasing points in the shape outline size.

Step 1: To reshape or edit the square: select the square, click on Effect menu and on the menu click Distort & Transform and then select the zigzag... effect. In the Zigzag dialog box, adjust the size to be 12 pts and ridges to be 5. then click OK.

To insert text in the square; select Type Tool on the toolbox and draw a box in shape where you can type text. type in the text in the shape. Change font size to 24pt, Book Antiqua; using the Character button on the upper toolbar. see picture 7.12(i).

To change text color, select typed text and click on red color from the CMYK spectrum colors on the right of the window or using alternative option on the upper toolbar. Lastly click the center button on the upper toolbar.

Step 2: To edit circle oval; select it and on the effect menu click Texture and then Traquelure. see picture 7.12 (k). In the Traquelure dialog box that displays, (you can adjust the crack spacing depth and brightness as you like), click OK. select radial gradient on the right.

the traquelure dialog is shown below

Step 3: to reshape the rounded rectangle, select it and click Effects  menu. on the menu, click Warp and select Shell lower in the sub menu.

to add special fill effects, click Pixelate on the effects menu and then select Mezzotint.

to add text to the rounded rectangle, repeat as done in step 1 above.

the suggested answers for the activity are shown in picture below.

Click on File menu and select Save As.the Illustrator options dialog box displays as shown below. Click OK. the save dialog box displays. type in the file name and click on ‘Save’ button.

these are the selection boxes and circles that appear when you select an image for reshaping. Point on one of the node or point until the pointer changes shape of double pointed arrow. then click and drag inwards or outwards to reduce size or enlarge its size respectively.

a) Create a new Paint file and draw a star object (another object of your choice).

b) Fill the object outline to color red and fill color to green (or light green).

c) Insert text as “star” in the star shape. Adjust the font size to a suitable size.

d) save the file as ‘Green star’.