Drawing Freehand


If the user has selected the Draw menu's Draw freehand item, he can use the mouse to draw freehand. As you'll recall, the successive locations of the mouse are stored in an array named dots if the user is drawing freehand, so all that's necessary is to connect those dots.

If the user wants a drop shadow, you should draw that first, then reproduce what the user has drawn with the mouse. Here's what it looks like in code:

     if(draw){         Line2D.Double drawLine;         if(shadow){             paint = gImage.getPaint();             composite = gImage.getComposite();             gImage.setPaint(Color.black);             gImage.setComposite(AlphaComposite.getInstance                 (AlphaComposite.SRC_OVER, 0.3f));             for(int loop_index = 0; loop_index < dots - 1;                 loop_index++){                 if(dragging){                     drawLine = new Line2D.Double(                         dot[loop_index].x + 9,                         dot[loop_index].y + 9,                         dot[loop_index + 1].x + 9,                         dot[loop_index + 1].y + 9);                 }else{                     drawLine = new Line2D.Double(                         dot[loop_index].x - offsetX + 9,                         dot[loop_index].y - offsetY + 9,                         dot[loop_index + 1].x - offsetX + 9,                         dot[loop_index + 1].y - offsetY + 9);                 }                 gImage.draw(drawLine);             }             gImage.setPaint(paint);             gImage.setComposite(composite);         }         for(int loop_index = 0; loop_index < dots - 1;             loop_index++){             if(dragging){                 drawLine = new Line2D.Double(dot[loop_index].x,                     dot[loop_index].y, dot[loop_index + 1].x,                     dot[loop_index + 1].y);             }else{                 drawLine = new Line2D.Double(dot[loop_index].x                     - offsetX, dot[loop_index].y - offsetY,                     dot[loop_index + 1].x - offsetX,                     dot[loop_index + 1].y - offsetY);             }             gImage.draw(drawLine);         }         if(!dragging){             dots = 0;         }     } } 

You can see an example in Figure 4.6, where the user is drawing freehand with the mouse and using a drop shadow.

Figure 4.6. Drawing freehand, with a drop shadow.




    Java After Hours(c) 10 Projects You'll Never Do at Work
    Java After Hours: 10 Projects Youll Never Do at Work
    ISBN: 0672327473
    EAN: 2147483647
    Year: 2006
    Pages: 128

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