Peter, To your original question about is OpenGL on Android internally float or fixed: See this document http://glprogramming.com/red/chapter02.html. It says
"OpenGL works in the homogeneous coordinates of three-dimensional projective geometry, so for internal calculations, all vertices are represented with four floating-point coordinates (x, y, z, w)...." Google engineers ported the OpenGL ES system to Android and layered the GLSurfaceView api over it. So my assumption is that the internal vertices are all in float. That says to me do do modeling and calculations in float and shut them to OpenGL. Then if there is a GPU things will render quicker than if there was not a GPU. Thanks, On Jan 6, 12:16 pm, Peter Eastman <peter.east...@gmail.com> wrote: > OpenGLES allows values to be specified in either fixed point or > floating point format, but I haven't been able to find any information > about how this is actually implemented on Android devices. Are there > actually two different pipelines, one for fixed point and one for > floating point? If so, what happens if you mix and match them, such > as specifying your matrix in floating point but your vertices in fixed > point? Alternatively, does it implement everything with just one > format internally, and convert the other format to it as necessary? > If so, then you presumably get the best performance if you always > specify values in the internal format so as to avoid conversions. How > then can I determine which format is used internally? > > I notice that the Matrix and Visibility classes only accept floating > point values for matrices. Should I interpret that as a > recommendation to use floating point for matrices? > > Peter
-- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
