vrenderparams -msaa 2 -alphaToCoverage 1
vdump $::imagedir/${::casename}_msaa2_cov.png
-vrenderparams -msaa 8 -alphaToCoverage 1
+vrenderparams -msaa 8 -alphaToCoverage 0
vdump $::imagedir/${::casename}_msaa8.png
vrenderparams -msaa 8 -alphaToCoverage 1