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now I get it, I finally understand where your disappointment feelings toward polyphony and wrong bad management idea came from, apparently you have no idea how polyphony digital implement cars in GT5...I really invite you to read more about this...
why just 200 premium cars ?!! in 6 years ?!! you polyphony bad resource managers...hire more people, model more cars and get the game out already damn it !
I understand now that you think modeling cars in GT5 is just about throwing some 500 000 polygons onto a car, so polyphony could just externalize this process or hire more people...(actually anyone could create a multi million polygon car, thats doesent mean the car is well modeled, polygons could be used efficiently or inefficiently, thats why GT4 cars on PS2 has 5000 polygons and they are better modeled than Forza 1 cars on xbox1 which use 20 000 + polygons per car)
so let me elighten you and tell you this :
1- for a lot of cars in GT5, polyphony staff travel to get pictures of those cars and any material that could be useful for the modelling process.
2- they also travel to TRY and DRIVE a lot of the cars they are modeling in the game (thats take a lot of time and money), do you know why ?
because the physics engine could only get you too far, because there is a difference between theoretical numbers and reality (0-60 seconds speed - brake, horse power, RPM, torque, gear transmission ratios, drivetrain type, wheight of the car, suspension type and chracteristics..) etc etc etc.
so after entering the characteristics of the car onto their pohysics engine simulation, they ADJUST the behavior of the car according to their driving experience with it.
It is true there is a physics engine, but thats sometimes more or less what polyphony do for some cars, for example just based on numbers, the physics engine cannot simulate accurately the incredible turning handling capabilities of the mitsubishi EVO (or the nissan GTR), thats why kazunori yamauchi drove those cars and adjusted their behavior in the game, making the car turn better and oversteer or understeer less than what the physics engine simulated based on theoritical numbers. the feeling of the car is also important (the car feels heavy ? light ? stable , unstable ? easy to drive ? difficult ? responsive or not ? how turning the wheel feels ?..etc those kind of parameters are difficult to simulate and set automatically in the physics engine and you need to adjust them manually for a realistic simulated driving experience of each car in the game)
thats actually what sets GT games apart from the majority of other racing games in the market :
attention to detail
thats why the experience of driving a car in NFS shft or PGR4 is less realistic than thats of GT5 prologue...
3/ the same thing goes to circuits, (they also try extensively a lot of circuits because the physics engine cant simulate accurately the felling of the circuit), thats why driving nurburgring in forza3 is different than GT4, and now GT5, in GT it is more realistic, more accurate, more authentic,
thats why it takes polyphony digital all those years to release the game (not the naive bad management
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but attention to detail)