Now one quick question comes to mind with respect to my other
application. If translucency isn't currently hardware accelerated - is
Java actually doing pixel tests for overlapping translucent objects?
If so, that would explain my performance woes. I would only want to
draw translucent stuff if I knew it was hardware accelerated.

I'm not sure what you mean by "pixel tests for overlapping translucent objects".

Whenever you draw translucently, if we software render it then it is a
read, modify, write operation.  We should have tests in most places
that test "if alpha is opaque then just write the pixel", though.  Have
you done tests that show that translucent rendering is too slow?  I'm
wondering why you prejudge that it won't be possible without hardware
acceleration.  There are a couple of things to be aware of for best
translucent rendering, though.

For example, software rendered translucency to a BufferedImage will be
much faster than translucency to most accelerated framebuffers until we
get acceleration for the translucency.  The reason is that most of the
latest framebuffers are much slower to read a pixel than to write a
pixel and the operation will bypass the processor cache, whereas a
BufferedImage will be stored in system memory and reading and writing
will be just simple memory operations to the processor's cache.

If you have an operation that is doing Area calculations on RR2Ds and
also rendering them translucently, I would think you are being hurt
more by the Area operations than by the blending operations, even if
they are software.  But, if you are rendering translucency directly to
the fb, then that may make the difference due to the added overhead of
poor readback performance from the framebuffer, but Area is not very
efficient with large numbers of objects...

                               ...jim

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