🚀 go-pugleaf

Aaron T wrote:
> 
> Okay I have got to build a program that will be able to draw gates to the
> screen (such as AND, OR, NOT etc) and flip flips, sources etc, pretty basic
> stuff. Also pins must be recorded on the canvas as the gates should be able
> to be connected.
> 
> I've been hard pressed to find a tutorial that deals with anything past the
> very basics of 2DGraphics in java, like drawing to screeen and so forth..
> 
> What I need to be able to do is draw to screen, but then later have the user
> able to select any gate and move it around. I kind of know how to do the
> moving with a update() or paint() method that is called by a mouse movement,
> but how do I make each shape (I'm using GeneralPath as the shape for a
> certain gate) a seperate 'object' that is able to be selected at will?

One approach is to make the various objects individual classes that know
how to paint and size themselves.  You could subclass JPanel and
override paintComponent(), getPreferredSize(), and perhaps some of the
other getXXXSize methods.  With this approach you can attach the
listener right to the component itself, and you don't have to bother
with figuring out which area of a single image (with several objects
painted on it) was clicked.

Once you have the components worked out, you will likely want to create
a custom layout manager that lets you drag things around, and perhaps
snaps to a 'grid' to make it easy to align components.  You can use a
'null' LayoutManager fo testing, but a custom layout will give you
better control.


Jim S.

Don't overload update - repaint when you need to. You can use any image
or imageIcon, maintain PositionX and PositionY as a function of Screen
width, and Screen Height. Use Java 2D Drag and Drop if you need to, but
I think you can do it with Java 1.1.

see http://www.tok2.net

Cheers,
            Terry O'K.

You by any chance dont go to Curtin University in Perth do you?
I did a unit where I had to do the exact same program.

I made each type of gate an object. The gates methods included draw,
position and logic state. Draw a staright line to an input pin on a
gate and have seperate applet 'state' which calculates the login. This
way only need an edit state and a calculaate state so you dont need to
calculate at every drawing update.

Joel


On Sat, 5 May 2001 10:54:48 +0800, "Aaron T" <toddam@dingoblue.net.au>
wrote:

>Okay I have got to build a program that will be able to draw gates to the
>screen (such as AND, OR, NOT etc) and flip flips, sources etc, pretty basic
>stuff. Also pins must be recorded on the canvas as the gates should be able
>to be connected.
>
>I've been hard pressed to find a tutorial that deals with anything past the
>very basics of 2DGraphics in java, like drawing to screeen and so forth..
>
>What I need to be able to do is draw to screen, but then later have the user
>able to select any gate and move it around. I kind of know how to do the
>moving with a update() or paint() method that is called by a mouse movement,
>but how do I make each shape (I'm using GeneralPath as the shape for a
>certain gate) a seperate 'object' that is able to be selected at will?
>
>Any help on the forum, email or pointers to websites would be great.. I've
>sifted the sun site, used the books I've bought and nothing seems to go into
>any great detail on this.
>
>Thanks very much
>Aaron Todd
>
>
>
>