[gl4java-usergroup] clear buffer with alpha values

[Thorsten R. <ro...@iv...>]

Hi *,

I thought the following code fragment would fill the window with well 
defined alpha values, why not ?

=== 8< ===

           gl.glClearColor (0f, 0f, 0f, alpha);
           gl.glColorMask (false, false, false, true);
           gl.glClear (GLFunc.GL_COLOR_BUFFER_BIT);

=== 8< ===

But when I'm also "unlocking" any of the r,g,b-parts in glClearColor,  
than it works! why ?

ciao, Thorsten