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applyImpulse on surface vs in air.

by Dustin Mellen · in Torque 3D Professional · 09/20/2010 (4:34 am) · 7 replies

Can anyone explain to me why applyImpulse affects the player differently when they are on a surface as opposed to in mid air? I've been wanting to apply a "knock back" effect to the player when colliding with enemy objects but, when applyImpulse is called while the player is in mid air it is thrown much farther than when standing on a surface. Is there any way to make the two effects equal?
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Torque Owner deepscratch
DeepScratchStudios
#1
09/20/2010 (5:58 pm)
well thats pretty much "real world" correct? no? any object, that, when given the same impulse force, when in the air, said object will travel further, than said object, on the ground.

Torque 3D Owner Dustin Mellen
#2
09/21/2010 (1:54 pm)
Well, there seems to be a vast difference between the distance you are pushed when on a surface compared to when you are in the air. I set my impulse value on the x-axis to 5000 and that throws the player the distance I was looking for (a couple meters), but when applied in mid air it throws the player ten times as much (I'm not sure how far because the player hits a wall first).

Torque 3D Owner Dustin Mellen
#3
09/21/2010 (2:02 pm)
Is there another way to apply a "knock back" effect? Should I just use the eye vector and multiply that by the distance I want to move the player back and apply it to .setTransform()?

Torque Owner Guy Allard
Default Studio Name
#4
09/21/2010 (4:20 pm)
Have you tried adding a small vertical component to the knockback impulse so that it lifts the player off the ground slightly?

Torque 3D Owner Dustin Mellen
#5
09/21/2010 (7:50 pm)
I tried that, but as soon as the player makes contact with the floor, the brakes come on and he stops. If he's in the air to start, it still goes too far.

Associate Matt Fairfax
PopCap
#6
09/21/2010 (7:57 pm)
If you look in the Movement fields in the PlayerData datablock there are a number of different settings that kick in based on whether or not the Player is in contact with the surface (particularly look at the various max speeds and the resist speeds). If there are different values for these, then it would make sense that you would get different results from an impulse.

Torque 3D Owner Dustin Mellen
#7
09/21/2010 (9:52 pm)
Regardless of how I set the horizMaxSpeed, horizResistSpeed, or the horizResistFactor, I get the same result. When the player is in the air, applyImpulse throws him like a bullet. As soon as he touches a horizontal surface, he stops on a dime. It's like he as 100% friction on his feet.