The following code produced the above:
| buildTurtleDemo | ||
| | v | | ||
| v := VisibilityTurtle newForPrinter: self printer . | "Create a new turtle object based on the current Visibility printer" | |
| v init; | "Initialise it" | |
| baseMeasurement: #mm; | "Set the measurement scheme to millimeters" | |
| pageSize: 100 @ 100; | "Set the page size to 100mm x 100mm" | |
| color: 16; | "Set the color to 16 = black in the current palette" | |
| currentBox: v pageSize; | "Set the current default box extent to the current page size (100mm x 100mm)" | |
| penDown; | "Set the pen for drawing" | |
| drawOpenBox; | "Draw a box of size 100mm x 100mm" | |
| toLeftCenter | "Move to the center point of the left hand side (a line is drawn because the pen is down." | |
| toBottomCenter | "Move to the center point of the bottom edge" | |
| toRightCenter | "Move to the center point of the right hand edge" | |
| toTopCenter | "Move to the center point of the top edge - a diamond has been drawn" | |
| toTopLeft; toBottomRight; toBottomLeft; toTopRight; |
"Now move to the four points defined - top left hand corner, and so on" | |
| penUp; | "Raise the pen - stop drawing" | |
| toCenter; | "Move to the center of the page" | |
| penDown; | "Lower the pen again" | |
| currentTextJustification: ##c; | "Set the text justification to center" | |
| text:'How to draw lines'. | "Draw some text using the current font at the current location using center justification" | |
| ^ v | "Answer the turtle." | |
Note that you could have drawn a diamond by using
the drawPolygon: anArray method with an array filled with the same locations.
| Click here for descriptions of the various commands and settings | Click here for a full list of commands and settings |
