Ok....time to drop some knowledge.
So i've built a few jumps, and been with some of the best jump builders in the world at cutter's camp. There are a few basic guidelines with jumps ( they are ONLY suggestions, and every mountain is different). So take offs have to be the same angle as the jump ( the angle of the jump before any sort of transition is put into the take off).
The landing schould also be about 2/1.5 times the lenght of the deck.
The best large take offs i've seen ( take off of 15 feet...50 foot deck) would be a 34 degree landing/take off. Works wonders. Smalls about 20 degrees. Medium jumps can be sort of in the middle. 45 degrees is something you see guys ride in MSP in alaska. So that doesn't work so well as a jump takeoff/landing.
Now there is also transitions, but this is done mostly by feel. After driving a while a cat driver will just know by feel and sight what type of transition works best for what kind of jump.
Hope that helps.