Wednesday, September 23, 2009

Sugar - Turtle art activity

Our class spent about three weeks looking at the activity, Turtle art on the sugar operating system.

Turtle art is an activity that allows a user to create pictures/shapes using various commands and values using a little turtle icon as the pen (e.g. forward 100 would move the turtle 100 steps forward from where it was). To get a command to work you had to double click on the command. Every command has bumps on them so that many other commands could join up with each other like Lego pieces. Once commands were joint together when we double clicked it all the commands would act at once.

This is the panel containing all the functions and commands:

There are also two modes, turtle mode (slow) and rabbit mode (fast). The rabbit mode made it so that with a click the shape co ordinates are drawn in immediately. The turtle mode made it so that we could view the movements of the turtle and that gave us a better understanding of what was going on.

Our 1st task was to create shapes that were shown on a page we were given and we would receive marks depending on the difficulty of shapes that we did. All shapes had to be drawn using one click instead of us clicking one command at a time and drawing it. To make it so we wouldn't have a long line of different direction commands, a function called repeat made this easier. This function had a value box next to it and whatever number was inside it, the repeat command would repeat whatever was under it, the number of times specified by us. Using one click prevented the lost of step because there was no way to undo something, we had to simply clear the whole shape and do it again. There were also other commands that did their own unique thing.

After we had gotten used to drawing more difficult shapes we were ask to add variables to draw shapes. A function called 'store in box' made a number variable of our choice. Next to every direction command there was always a value telling the turtle how far to travel, if that value were to be replaced with a 'box ' command then the value changes to whatever was in the 'store in box' command. This was helpful for changing a shape's size because we could just change the number in the 'store in box' and it would change the size of the shape depending on the number placed in the command without have to go to each value and changing their numbers.

The shape i drew on Turtle art using variables:

The command script i used to create the shape:

All the shapes we did had to be extremely perfect and precise to what the pictures on the sheet looked like, therefore when adding variables we must made sure we used divide and multiply commands in order to keep a shapes dimensions. Some shapes may only have looked the same but they weren't exactly perfect. There were two ways to work out what values were needed in order to create a shape which could change in size and still keep it's correct dimensions. First was to use trial and error and we had to simply guess each value until we got it correct. The other way was to use mathmetics and actually calculate the values. I mostly used trial and error because i was too lazy to do the maths but in the end i found that using maths i got a much more accurate shape.

Tutle art:

My thoughts on Turtle art is that at first it was hard to understand but I gradually began to understand how things worked ad i became easier for me. It was enjoyable working with this activity although the sugar occasionally froze when we tried to save a finished shape.

Tuesday, September 1, 2009

Creating own sugar icon

Learning about SVG (scalable vector graphic), we were told to create our own sugar icon using the same concept as an SVG. An SVG is a picture format which is small in size and uses maths to create its unique property. It's unique property is that when re sized, an SVG does not lose it's picture quality and pixelates.

Using Html kit we learnt about basic x and y co-ordinates of simple shapes, lines and curves and a 55 by 55 grid. We had done a few practices using coordinates to draw in shapes and lines. using what we had learnt it was then time to create our own icon to that we could later use that picture and put it onto the sugar operating system as our icon.

This is my icon i made using a few straight line co-ordinates and many curve/arc co-ordinates ;viewed on opera an internet browser:

After finishing our icon, all we had to do was using terminal activity on sugar to insert the picture as the icon. We could then make it change colour to what ever we wanted and demonstrating that we have done this to our teacher. Below is a screenshot of what my changed icon looks like, a bat looking creature.