thanks I'll get on to it as soon as possible. btw, the setResizeNonPowerOfTwoHint(false) solved the rescaling.
thanks, Guy. ----- Original Message ----- From: "Robert Osfield" <[EMAIL PROTECTED]> To: "osg users" <osg-users@openscenegraph.net> Sent: Thursday, June 28, 2007 9:55 AM Subject: Re: [osg-users] Reading from texture > Hi, > > OSG-2.0 does support a wider range of pixel formats so rather than > chase ghosts it would probably be best just upgrading. Porting to 2.0 > should not be that difficult, if you use osgProducer there is the > library still existing as its own separate project and works fine with > 2.0. The core OSG has seen a number of changes, but most shouldn't > effect backwards compatibility too much. > > Robert. > > On 6/28/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > > > ----- Original Message ----- > > From: "Robert Osfield" <[EMAIL PROTECTED]> > > To: "osg users" <osg-users@openscenegraph.net> > > Sent: Tuesday, June 26, 2007 3:28 PM > > Subject: Re: [osg-users] Reading from texture > > > > > > > On 6/26/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > > > Thanks for the advice, > > > > After implementing it, I encountered 3 problems: > > > > 1. There are minor differences of the data values between the two > > > > implementations (reading from the current texture, and attaching image) > > > > maybe images doesn't support half float precision? > > > > > > There is some half float support in the 2.0 version of osg::Image, but > > > this might not coverage your usage. > > > > > > > I'm still working with OSG1.2. currently I don't have time for the porting > > (even that I played a little with OSG2.0 on my free time :)). anyway, I will > > try to compile the OSG2.0 image code with OSG1.2 and see what happens. > > > > > > 2. The image was rescaled to power of 2. (300x300 ---> 256x256) while > > > > textures sizes don't have to be power of two. (is there a way to define > > > > image that won't be a power of 2 and attach it to the FBO?) > > > > > > What makes you think the images are rescaled to a power of two when > > > reading? There isn't any such code. > > > > I don't remember the exact words but OSG prompts in the console something > > like "rescaling (300x300) image to (256x256)". > > > > > There only code for rescaling to > > > power of two happens when applying on non power of two image to a > > > power of two texture. > > > > I allocated both at the same code section using the same width and height. > > > > > Note the OSG support non power of two texture > > > where supported by OpenGL drivers, but by default this is switched off > > > due to portability problems related to OpenGL driver saying non power > > > of two is supported, but then implementing it in software... > > > > > > See osg::Texture::setResizeNonPowerOfTwoHint(bool); > > > > I'll look for it. > > > > > > > > > 3. It run slower than binding the texture object and reading from > > current > > > > texture. > > > > > > It shouldn't run slower, if it is then there is possible some issue > > > along the way such as pixel formats being inconsistent. > > > > Both are using GL_RGBA mode with GL_FLOAT as the type. The texture has > > internal format of half float, I don't seem to remember setting the image to > > half float but I did what I saw in one of the examples that show how to > > attach image to texture and having the texture automaticlly updated when the > > image is changed. > > Could that be the problem? is it possible to set image "internalFormat"? > > did you mean something else by pixel format? > > > > > > > > Robert. > > > > thanks, > > Guy. > > > _______________________________________________ > > > osg-users mailing list > > > osg-users@openscenegraph.net > > > http://openscenegraph.net/mailman/listinfo/osg-users > > > http://www.openscenegraph.org/ > > > > > > > > > _______________________________________________ > > osg-users mailing list > > osg-users@openscenegraph.net > > http://openscenegraph.net/mailman/listinfo/osg-users > > http://www.openscenegraph.org/ > > > _______________________________________________ > osg-users mailing list > osg-users@openscenegraph.net > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list osg-users@openscenegraph.net http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
