Right, format is rgba, but alpha channel not enabled in shader.ijs it needs to add 2 lines, glEnable GL_BLEND glBlendFunc GL_SRC_ALPHA; GL_ONE_MINUS_SRC_ALPHA
otherwise alpha is ignored. Fri, 28 Feb 2020, Raul Miller написал(а): > On Fri, Feb 28, 2020 at 2:09 PM Brian Schott <[email protected]> wrote: > > Of course I am still struggling with painting the faces of the tetrahedrons > > as solid colors. They are my tentative turtles. I am now wondering if my > > problem is related to the use of four-element color vectors instead of > > three element. I have not found any description of how to set those things > > in the kernel as you seem to have done. And does this setting conflict with > > the attribute setting that I changed from 3 to 4? > > Just as a reminder: four element "color" in opengl is typically rgba: > red, green, blue, alpha. > > The alpha color channel ranges from 0 (transparent) to 1 (opaque) in > typical application (but shaders are free to re-interpret color > information arbitrarily -- the definitive color is what's emitted by > the pixel shader). > > https://www.khronos.org/opengl/wiki/Image_Format > > Thanks, > > -- > Raul > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm -- regards, ==================================================== GPG key 1024D/4434BAB3 2008-08-24 gpg --keyserver subkeys.pgp.net --armor --export 4434BAB3 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
