vImage is a pretty fast way to do it. Requires ios5 though. The call says ARGB but it works for the BGRA you get from the buffer. This also has the advantage that you can cut out a part of the buffer and rotate that. See my answer here – (unsigned char*) rotateBuffer: (CMSampleBufferRef) sampleBuffer … Read more
The AffineTransform associated with the graphics context passed to paintComponent() is not always the identity transform. For reasons that aren’t clear, the m12 entry has the value 38.0 initially and after resizing the enclosing frame. Trivially, one can modify the copy supplied by g.create(). Graphics2D g2d = (Graphics2D) g.create(); AffineTransform at = g2d.getTransform(); at.translate(originX, originY); … Read more
Note that AffineTransform transformations are concatenated “in the most commonly useful way”, which may be regarded as last in, first-out order. The effect can be seen in this example. Given the sequence below, the resulting Shape is first rotated, then scaled and finally translated. at.translate(SIZE/2, SIZE/2); at.scale(60, 60); at.rotate(Math.PI/4); return at.createTransformedShape(…);
Okay, this is a little slight of hand. The example code will only work for 90 degree increments (it was only designed this way), to do smaller increments you to use some trig to calculate the image width and height (there’s a answer somewhere for that to ;)) public class ImagePane extends JPanel { private … Read more
You need to be using trigonometry to determine the correct width/height, using transparency to prevent the black area, and I think the Transform is wrong, which is making it off center. Try this: public static BufferedImage rotate(BufferedImage image, double angle) { double sin = Math.abs(Math.sin(angle)), cos = Math.abs(Math.cos(angle)); int w = image.getWidth(), h = image.getHeight(); … Read more
The major problem (that I can see) is the translation of the Graphics context which is offset the position that the rotation will take place. I “think” rotation by default occurs at the top/left corner of the Graphics context (where it’s 0x0 position is, which you’ve translated to something else), this could be causing the … Read more
“I want the object to randomly pop up from the bottom of the screen reach a certain ascent and then fall back down” See the runnable example below. What I do is pass a radomDelayedStart to the Shape. Every tick of the timer, the randomDelayedStart decreases til it reaches 0, that’s when the flag to … Read more
One approach is shown in SineTest. In outline, Save the graphics context’s transform. Graphics2D g2d = (Graphics2D) g; AffineTransform at = g2d.getTransform(); Translate the origin to the center. g2d.translate(w / 2, h / 2); Invert the y-axis. g2d.scale(1, -1); Render using cartesian coordinates. Restore the transform for conventional rendering. g2d.setTransform(at);