change alpha ramp draws to indexed, hopefully fixes missing balls on some tables again, maybe even a bit faster

git-svn-id: svn://svn.code.sf.net/p/vpinball/code/trunk@496 14438d79-0ffd-4333-8ae7-ea2bdd901387
slightly optimize alpha ramp vertex generation

git-svn-id: svn://svn.code.sf.net/p/vpinball/code/trunk@497 14438d79-0ffd-4333-8ae7-ea2bdd901387
bumper animation fixed

git-svn-id: svn://svn.code.sf.net/p/vpinball/code/trunk@498 14438d79-0ffd-4333-8ae7-ea2bdd901387