Rotating Sprites [Solved]

Hey Everyone,

I am using pure Java, no 3rd party libraries and I want to be able to rotate one of my sprites. My sprite is 16x16 pixels. Right now i know how to rotate with AffineTransformation but for some reason when it rotates the sprite looks very weird. This might be due to it being very small. but maybe someone could help me. Thanks

~GlennBrann

How exactly is it looking weird? Rotation will come with a (more or less ) notable loss of quality, depeing on the exact setting (anti-aliasing, transparency etc.)

I seem to remember that old games had all rotations as separate sprites, mostly likely all views were separetly made or retouched. I don’t know if rotation was just too slow that times, or if it was a quality problem.

Do you want to just flip / mirror or do a 90 Degree turn,
or do you want to make a fine rotation (under 90 Degrees)

In the case of a fine rotation, I suggest to use a propper graphics program for this, and render every frame
onto a bitmap, this will have much better quality and is faster to render (unless you prerender your graphics).

I can help you with this! ;D

Ive had a simmiliar issue and the reason for it is because when you use affinetransform even if you are not using any antiailiasing when you rotate an image multiple times it begins to be “weird”.

So the answer to this is to instead of actually rotating the image, you should store a double with the desired rotation and right before rendering rotate it that amount and render the rotated image. The rendered image will be perfect.

Code example from TheEntropyGameEngine :

                AffineTransform at = new AffineTransform();
                
                at.translate(image.getImageLocationX(), image.getImageLocationY());
                at.rotate(image.getImageRotation(), image.imageSrc.getWidth()/2, image.imageSrc.getHeight()/2);
                
                Graphics2D g2d = (Graphics2D) g;
                g2d.drawImage(image.imageSrc, at, null);

Within the,

paintComponent(Graphics g)

Remember that all the image.whatever(); code is irrelevant to you, that is specific data for rendering objects in my engine.