java - How can I rotate an Area object on its axis while also moving it along the y axis? -

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so have area object have created , made 4 star polygon. want rotate object while simultaneously having translate along y axis. code points use create object , center of star xloc , yloc paint function below that:

double rots = 0.0; int xpoints[] = { 45, 48, 56, 48, 45, 42, 34, 42 }; int ypoints[] = { 56, 47, 45, 43, 34, 43, 45, 47 }; double xloc = 150, yloc = 250;

public void paint(graphics g) {     graphics2d g2d = (graphics2d) g;     renderinghints rh = new renderinghints( renderinghints.key_antialiasing, renderinghints.value_antialias_on);     rh.put(renderinghints.key_rendering, renderinghints.value_render_quality);         g2d.setrenderinghints(rh);     g2d.translate(xloc, yloc);    g2d.rotate(rots);       g2d.fill(star);    //yloc += .01;     rots += .001;      repaint();   }

the problem i'm having in paint function. getrotateinstance spins along axis of xloc , yloc. when numbers incremented, star's rotation widens out origin encompass whole screen. solution can think of change xpoints[] , ypoints[] haven't been successful far. there way make work or way fix problem i'm having?

edit: made progress! took advice given , i'm close. replace code affinetransform trans = affinetransform.getrotateinstance this:

affinetransform trans = new affinetransform(); trans.settotranslation(xloc, yloc); trans.rotate(rots);

now rotates , moves across screen though doesn't rotate around increasingly large field, still rotates around point can't seem make out. i'm guess has xloc , yloc points are. based on tests before, xloc , yloc should centered @ origin should spinning correctly. suggestions?

edit 2: received advice saying should use graphics2d functions translation , rotation. changed affinetransform statements this:

g2d.translate(xloc, yloc); g2d.rotate(rots);

the problem having while star translate , rotate, seems making additional rotation. rotate @ origin , rotates around additional point can't make out while translating along y axis. have better better understanding of looks like, imagine planet rotating night , day, circling star , moving in straight line. have updated code above reflect changes. how can fix this?

by changing double xloc = 150, yloc = 250; int xloc = 150, yloc = 250; fixed problem. however, moving fast added timer slow things down , it.

my guess ints not playing doubles. shapes had in int making variables double , applying tranformation, messing up.


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