scale() and shape() in Processing

UPDATE: I think I figured it out. The scaleMultiplier also applied to the translate that I was trying to do. I had a suspicion this was the case but couldn't figure out exactly how it got affected.

Anyone familiar with a spinoff of Java called Processing? I'm trying to do something simple, scale a shape and place it in the center of the sketch. This is my code in a nutshell:

pushMatrix();

float scaleX, scaleY, scaleMultiplier, resetX, resetY, transX, transY;

scaleX = 500 / (float)clickState.bounds.getWidth();
scaleY = 500 / (float)clickState.bounds.getHeight();
scaleMultiplier = min(scaleX,scaleY);
resetX = -(float)clickState.bounds.getX();
resetY = -(float)clickState.bounds.getY();

transX = resetX + ((800 - ((float)clickState.bounds.getWidth() * scaleMultiplier))/2);
transY = resetY + ((550 - ((float)clickState.bounds.getHeight() * scaleMultiplier))/2);

scale(scaleMultiplier);
shape(clickState.pshape, transX, transY);

popMatrix();

What I'm trying to do is scale a state on a US Map. clickState is the state that the user clicked on. clickState.bounds is a Rectangle that surrounds the shape of the state. getX() and getY() return the x and y coor开发者_Python百科ds of the upper left hand corner of said box. I want to scale the state so that it's no bigger than 500x500 pixels. After that, I want to translate it so that it's in the middle of the sketch, which is 800x550.

Here's where I run into trouble: When I do

shape(clickState.pshape, resetX, resetY);

It draws the state in the upper left hand corner of the sketch. That's exactly what it should do. Then from there I want to add the number of pixels that it would take to center the shape, which is what transX and transY are for. However, when I use transX and transY, the shape gets drawn almost completely off the canvas, depending on where the state is located (even if its only being moved 50 pixels to the right from 0,0). It doesn't make any sense to me whatsoever. I've tried all sorts of combinations of translate(), and even skipping scale() altogether and using a width and height in shape(). It's like Processing is trying to frustrate me on purpose. Any help is appreciated.

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I'm not familiar with Processing, but matrix operations are not commutative—the order matters. Typically, operations are applied in an apparent last-specified-first-applied order, as shown in this example.

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Vince, I think I was trying to do something very similar last week. Sounds like you figured it out, but check out the answers on this board:

http://forum.processing.org/topic/how-do-i-move-svg-child-shapes#25080000000689051